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Abele N, Münz F, Zink F, Gröger M, Hoffmann A, Wolfschmitt EM, Hogg M, Calzia E, Waller C, Radermacher P, Merz T. Relation of Plasma Catecholamine Concentrations and Myocardial Mitochondrial Respiratory Activity in Anesthetized and Mechanically Ventilated, Cardiovascular Healthy Swine. Int J Mol Sci 2023; 24:17293. [PMID: 38139121 PMCID: PMC10743631 DOI: 10.3390/ijms242417293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 12/24/2023] Open
Abstract
Chronic heart failure is associated with reduced myocardial β-adrenergic receptor expression and mitochondrial function. Since these data coincide with increased plasma catecholamine levels, we investigated the relation between myocardial β-receptor expression and mitochondrial respiratory activity under conditions of physiological catecholamine concentrations. This post hoc analysis used material of a prospective randomized, controlled study on 12 sexually mature (age 20-24 weeks) Early Life Stress or control pigs (weaning at day 21 and 28-35 after birth, respectively) of either sex. Measurements in anesthetized, mechanically ventilated, and instrumented animals comprised serum catecholamine (liquid-chromatography/tandem-mass-spectrometry) and 8-isoprostane levels, whole blood superoxide anion concentrations (electron spin resonance), oxidative DNA strand breaks (tail moment in the "comet assay"), post mortem cardiac tissue mitochondrial respiration, and immunohistochemistry (β2-adrenoreceptor, mitochondrial respiration complex, and nitrotyrosine expression). Catecholamine concentrations were inversely related to myocardial mitochondrial respiratory activity and β2-adrenoceptor expression, whereas there was no relation to mitochondrial respiratory complex expression. Except for a significant, direct, non-linear relation between DNA damage and noradrenaline levels, catecholamine concentrations were unrelated to markers of oxidative stress. The present study suggests that physiological variations of the plasma catecholamine concentrations, e.g., due to physical and/or psychological stress, may affect cardiac β2-adrenoceptor expression and mitochondrial respiration.
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Affiliation(s)
- Nadja Abele
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
| | - Franziska Münz
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
- Clinic for Anesthesiology and Intensive Care, Ulm University Medical Center, 89069 Ulm, Germany
| | - Fabian Zink
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
| | - Michael Gröger
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
| | - Andrea Hoffmann
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
| | - Eva-Maria Wolfschmitt
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
| | - Melanie Hogg
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
| | - Enrico Calzia
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
| | - Christiane Waller
- Clinic for Psychosomatic Medicine and Psychotherapy, Paracelsus Medical Private University, 90402 Nuremberg, Germany;
| | - Peter Radermacher
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
| | - Tamara Merz
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, 89069 Ulm, Germany; (N.A.); (F.Z.); (M.G.); (A.H.); (E.-M.W.); (M.H.); (E.C.)
- Clinic for Anesthesiology and Intensive Care, Ulm University Medical Center, 89069 Ulm, Germany
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Karim S, Chahal A, Khanji MY, Petersen SE, Somers V. Autonomic Cardiovascular Control in Health and Disease. Compr Physiol 2023; 13:4493-4511. [PMID: 36994768 PMCID: PMC10406398 DOI: 10.1002/cphy.c210037] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Autonomic neural control of the cardiovascular system is formed of complex and dynamic processes able to adjust rapidly to mitigate perturbations in hemodynamics and maintain homeostasis. Alterations in autonomic control feature in the development or progression of a multitude of diseases with wide-ranging physiological implications given the neural system's responsibility for controlling inotropy, chronotropy, lusitropy, and dromotropy. Imbalances in sympathetic and parasympathetic neural control are also implicated in the development of arrhythmia in several cardiovascular conditions sparking interest in autonomic modulation as a form of treatment. A number of measures of autonomic function have shown prognostic significance in health and in pathological states and have undergone varying degrees of refinement, yet adoption into clinical practice remains extremely limited. The focus of this contemporary narrative review is to summarize the anatomy, physiology, and pathophysiology of the cardiovascular autonomic nervous system and describe the merits and shortfalls of testing modalities available. © 2023 American Physiological Society. Compr Physiol 13:4493-4511, 2023.
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Affiliation(s)
- Shahid Karim
- Mayo Clinic, Rochester, Minnesota, USA
- William Harvey Research Institute, NIHR Barts Biomedical Centre, Queen Mary University London, UK
| | - Anwar Chahal
- Mayo Clinic, Rochester, Minnesota, USA
- University of Pennsylvania, Pennsylvania, USA
- William Harvey Research Institute, NIHR Barts Biomedical Centre, Queen Mary University London, UK
| | - Mohammed Y. Khanji
- William Harvey Research Institute, NIHR Barts Biomedical Centre, Queen Mary University London, UK
- Barts Heart Centre, St Bartholomew’s Hospital, Barts Health NHS Trust, London, UK
- Newham University Hospital, Barts Health NHS Trust, London, UK
| | - Steffen E. Petersen
- William Harvey Research Institute, NIHR Barts Biomedical Centre, Queen Mary University London, UK
- Barts Heart Centre, St Bartholomew’s Hospital, Barts Health NHS Trust, London, UK
- Health Data Research UK, London, UK
- Alan Turing Institute, London, UK
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Kokosińska D, Żebrowski JJ, Buchner T, Baranowski R, Orłowska-Baranowska E. Asymmetric multiscale multifractal analysis (AMMA) of heart rate variability. Physiol Meas 2021; 42. [PMID: 34315141 DOI: 10.1088/1361-6579/ac184c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 07/27/2021] [Indexed: 12/20/2022]
Abstract
Objective.The physiological activity of the heart is controlled and modulated mostly by the parasympathetic and sympathetic nervous systems. Heart rate variability (HRV) analysis is therefore used to observe fluctuations that reflect changes in the activity in these two branches. Knowing that acceleration and deceleration patterns in heart rate fluctuations are asymmetrically distributed, the ability to analyze HRV asymmetry was introduced into MMA.Approach. The new method is called asymmetric multiscale multifractal analysis (AMMA) and the analysis involved six groups: 36 healthy persons, 103 cases with aortic valve stenosis, 36 with hypertrophic cardiomyopathy, 32 with atrial fibrillation, 59 patients with coronary artery disease (CAD) and 13 with congestive heart failure.Main results. Analyzing the results obtained for the 6 groups of patients based on the AMMA method, i.e. comparing the Hurst surfaces for heart rate decelerations and accelerations, it was noticed that these surfaces differ significantly. And the differences occur in most groups for large fluctuations (multifractal parameterq > 0). In addition, a similarity was found for all groups for the AMMA Hurst surface for decelerations to the MMA Hurst surface-heart rate decelerations (lengthening of the RR intervals) appears to be the main factor determining the shape of the complete Hurst surface and so the multifractal properties of HRV. The differences between the groups, especially for CAD, hypertrophic cardiomyopathy and aortic valve stenosis, are more visible if the Hurst surfaces are analyzed separately for accelerations and decelerations.Significance. The AMMA results presented here may provide additional input for HRV analysis and create a new paradigm for future medical screening. Note that the HRV analysis using MMA (without distinguishing accelerations from decelerations) gave satisfactory screening statistics in our previous studies.
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Affiliation(s)
- Dorota Kokosińska
- Faculty of Physics, Warsaw University of Technology, Complex Systems, Warsaw 00-662, Poland
| | - Jan Jacek Żebrowski
- Faculty of Physics, Warsaw University of Technology, Complex Systems, Warsaw 00-662, Poland
| | - Teodor Buchner
- Faculty of Physics, Warsaw University of Technology, Complex Systems, Warsaw 00-662, Poland
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Abstract
PURPOSE OF REVIEW The present article reviews the pathophysiology of cardiac sympathetic denervation, the principles of positron emission tomography (PET) imaging of the sympathetic innervation of the heart and its potential clinical role, based on current and expected future evidence. RECENT FINDINGS Imaging of cardiac sympathetic denervation can be performed with radiolabeled noradrenaline analogues, e.g., 11C-hydroxyephedrine. A greater burden of sympathetic denervation carries prognostic significance, e.g., in patients with ischemic cardiomyopathy and a left ventricular ejection fraction ≤ 35%, who are more likely to experience sudden cardiac death. Abnormalities of sympathetic cardiac innervation have been demonstrated in hypertrophic, dilated, and arrhythmic right ventricular cardiomyopathies, and may be helpful in better phenotyping patients who will benefit from device therapy, e.g., cardiac resynchronization and implantable cardioverter-defibrillator implantation. The results of future trials, e.g., the Prediction of Arrhythmic Events with Positron Emission Tomography (PAREPET) II study, are awaited to inform on the role of PET cardiac sympathetic imaging in the selection of device therapy. PET cardiac sympathetic innervation imaging allows visualization and quantification of autonomic denervation secondary to various cardiac diseases, and has significant potential to influence clinical decision-making, e.g., the titration of pharmacotherapy and more directed selection of candidates for device implantation.
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Suárez Bagnasco M, Núñez-Gil IJ. Psychological disorders in adults with inherited cardiomyopathies and Takotsubo syndrome. Medwave 2016; 16:e6460. [DOI: 10.5867/medwave.2016.05.6460] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 05/27/2016] [Indexed: 11/27/2022] Open
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Nuclear Imaging for Assessment of Myocardial Perfusion, Metabolism, and Innervation in Hypertrophic Cardiomyopathy. CURRENT CARDIOVASCULAR IMAGING REPORTS 2016. [DOI: 10.1007/s12410-016-9379-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Bernacki GM, Bahrainy S, Caldwell JH, Levy WC, Link JM, Stratton JR. Assessment of the Effects of Age, Gender, and Exercise Training on the Cardiac Sympathetic Nervous System Using Positron Emission Tomography Imaging. J Gerontol A Biol Sci Med Sci 2016; 71:1195-201. [PMID: 26957471 DOI: 10.1093/gerona/glw020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 01/29/2016] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Using positron emission tomography (PET) imaging, we sought to determine whether normal age or exercise training cause changes in the cardiac sympathetic nervous system function in male or female healthy volunteers. METHODS Healthy sedentary participants underwent PET studies before and after 6 months of supervised exercise training. Presynaptic uptake by the norepinephrine transporter-1 function was measured using PET imaging of [(11)C]-meta-hydroxyephedrine, a norepinephrine analog, and expressed as a permeability-surface area product (PSnt in mL/min/mL). Postsynaptic function was measured as β-adrenergic receptor density (β'max in pmol/mL tissue) by imaging the β-receptor antagonist [(11)C]-CGP12177. Myocardial blood flow (MBF in mL/min/mL tissue) was measured by imaging [(15)O]-water. RESULTS At baseline, there was no age difference in β'max or MBF but PSnt declined with age (1.12±0.11 young vs 0.87±0.06 old, p = .036). Before training, women had significantly greater MBF (0.87±0.03 vs 0.69±0.03, p < .0001) and PSnt (1.14±0.08 vs 0.75±0.07, p < .001) than men. Training increased VO2 max by 13% (p < .0001), but there were no training effects on β'max, PSnt, or MBF. Greater MBF in females and a trend to increased PSnt post-training persisted. CONCLUSION With age, presynaptic uptake as measured by PSnt declines, but there were no differences in β'max. Endurance training significantly increased VO2 max but did not cause any changes in the measures of cardiac sympathetic nervous system function. These findings suggest that significant changes do not occur or that current PET imaging methods may be inadequate to measure small serial differences in a highly reproducible manner.
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Affiliation(s)
| | | | - James H Caldwell
- Division of Cardiology, Department of Medicine and Division of Nuclear Medicine, Department of Radiology, VA Medical Center and University of Washington, Seattle. Department of Radiology, University of Washington, Seattle
| | - Wayne C Levy
- Division of Cardiology, Department of Medicine and
| | - Jeanne M Link
- Department of Diagnostic Radiology, Oregon Health & Science University, Portland
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Friedrich FW, Sotoud H, Geertz B, Weber S, Flenner F, Reischmann S, Eschenhagen T, Carrier L, El-Armouche A. I-1-deficiency negatively impacts survival in a cardiomyopathy mouse model. IJC HEART & VASCULATURE 2015; 8:87-94. [PMID: 28785686 PMCID: PMC5497269 DOI: 10.1016/j.ijcha.2015.05.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 05/20/2015] [Accepted: 05/25/2015] [Indexed: 10/31/2022]
Abstract
AIMS Hypertrophic cardiomyopathy (HCM) is characterized by left ventricular hypertrophy, diastolic dysfunction and increased interstitial fibrosis. Current treatment is based on beta-adrenoceptor (AR) and calcium channel blockers. Since mice deficient of protein phosphatase-1 inhibitor-1 (I-1), an amplifier in beta-AR signalling, were protected from pathological adrenergic stimulation in vivo, we hypothesized that I-1 ablation could result in an improved outcome in a HCM mouse model. METHODS AND RESULTS We crossed mice deficient of I-1 with homozygous myosin-binding protein C knock-out (Mybpc3 KO) mice exhibiting cardiac dilatation and reduced survival. Unexpectedly, survival time was shorter in double I-1/Mybpc3 KO than in single Mybpc3 KO mice. Longitudinal echocardiographic assessment revealed lower fractional area change, and higher diastolic left ventricular inner dimensions and end-diastolic volumes in Mybpc3 KO than in WT mice. In comparison to Mybpc3 KO, double I-1/Mybpc3 KO presented higher left ventricular end-diastolic volumes, inner dimensions and ventricular surface areas with increasing differences over time. Phosphorylation levels of PKA-downstream targets and mRNA levels of hypertrophic markers did not differ between I-1/Mybpc3 KO and single Mybpc3 KO mice, except a trend towards higher beta-myosin heavy chain levels in double I-1/Mybpc3 KO. CONCLUSION The data indicate that interference with beta-AR signalling has no long-term benefit in this severe MYBPC3-related cardiomyopathy mouse model.
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Affiliation(s)
- Felix W Friedrich
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, Germany
| | - Hannieh Sotoud
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, Germany
| | - Birgit Geertz
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, Germany
| | - Silvio Weber
- Department of Pharmacology and Toxicology, University of Technology Dresden, Germany
| | - Frederik Flenner
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, Germany
| | - Silke Reischmann
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, Germany
| | - Thomas Eschenhagen
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, Germany
| | - Lucie Carrier
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, Germany
| | - Ali El-Armouche
- Department of Pharmacology and Toxicology, University of Technology Dresden, Germany
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Patel V, Critoph CH, Finlay MC, Mist B, Lambiase PD, Elliott PM. Heart rate recovery in patients with hypertrophic cardiomyopathy. Am J Cardiol 2014; 113:1011-7. [PMID: 24461767 PMCID: PMC4038954 DOI: 10.1016/j.amjcard.2013.11.062] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 11/26/2013] [Accepted: 11/26/2013] [Indexed: 11/27/2022]
Abstract
Recovery in heart rate (HR) after exercise is a measure of autonomic function and a prognostic indicator in cardiovascular disease. The aim of this study was to characterize heart rate recovery (HRR) and to determine its relation to cardiac function and morphology in patients with hypertrophic cardiomyopathy (HC). We studied 18 healthy volunteers and 41 individuals with HC. All patients underwent clinical assessment and transthoracic echocardiography. Continuous beat-by-beat assessment of HR was obtained during and after cardiopulmonary exercise testing using finger plethysmography. HRR and power spectral densities were calculated on 3 minutes of continuous RR recordings. Absolute HRR was lower in patients than that in controls at 1, 2, and 3 minutes (25.7 ± 8.4 vs 35.3 ± 11.0 beats/min, p <0.001; 36.8 ± 9.4 vs 53.6 ± 13.2 beats/min, p <0.001; 41.2 ± 12.2 vs 62.1 ± 14.5 beats/min, p <0.001, respectively). HRR remained lower in patients at 2 and 3 minutes after normalization to peak HR. After normalization to the difference in HR between peak exercise and rest, HRR was significantly impaired in individuals with obstructive HC at 3 minutes compared with controls. HR at 3 minutes correlated with peak left ventricular outflow tract gradient (B 0.154 beats/min/mm Hg, confidence interval 0.010 to 0.299, p = 0.037) and remained a significant predictor of HRR after multivariable analysis. Spectral analysis showed a trend toward an increased low-frequency to high-frequency ratio in patients (p = 0.08) suggesting sympathetic predominance. In conclusion, HRR is impaired in HC and correlates with the severity of left ventricular outflow tract gradient. Prospective studies of the prognostic implications of impaired HRR in HC are warranted.
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Katarzynska-Szymanska A, Ochotny R, Oko-Sarnowska Z, Wachowiak-Baszynska H, Krauze T, Piskorski J, Gwizdala A, Mitkowski P, Guzik P. Shortening baroreflex delay in hypertrophic cardiomyopathy patients -- an unknown effect of β-blockers. Br J Clin Pharmacol 2012; 75:1516-24. [PMID: 23126403 DOI: 10.1111/bcp.12027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 10/31/2012] [Indexed: 12/15/2022] Open
Abstract
AIMS Hypertrophic cardiomyopathy (HCM) is characterized by left ventricular hypertrophy and impaired diastolic and systolic function. Abnormal sympathetic-parasympathetic balance is a potential stimulus for left ventricular hypertrophy in HCM patients. β-Blockers are routinely used in HCM for their strong negative inotropic effect; however, these drugs also influence the sympathetic-parasympathetic balance. This study aimed to determine the autonomic control of the cardiovascular system and the autonomic effects of β-blockers in HCM patients treated or untreated with β-blockers. METHODS Among 51 HCM outpatients (18-70 years old; 29 men) there were 19 individuals with no medication and 32 subjects treated with a β-blocker. Fourteen age- and gender-matched (23-70 years old; nine men) healthy volunteers were enrolled in the control group. Continuous, non-invasive finger blood pressure was recorded during supine rest for 30 min. Autonomic regulation of the cardiovascular system was measured by heart rate variability and spontaneous baroreflex function (cross-correlation sequence method). RESULTS The mean pulse interval, time domain and spectral measures of heart rate variability and baroreflex sensitivity were comparable between HCM patients, treated or not with β-blockers, and the control group. However, the delay of the baroreflex was significantly longer in HCM patients who were not treated with β-blockers [2.0 (1.6-2.3) s] in comparison with HCM patients receiving β-blockers [1.4 (1.1-1.8) s; P = 0.0072] or control subjects [1.2 (0.8-1.8) s; P = 0.0025]. This delay did not differ between HCM patients treated with β-blockers and the control group. CONCLUSIONS Hypertrophic cardiomyopathy not treated with β-blockers is accompanied by prolonged baroreflex delay. The use of β-blockers normalizes this delay.
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Eleventh international symposium on radiopharmaceutical chemistry: Abstracts. J Labelled Comp Radiopharm 2012. [DOI: 10.1002/jlcr.2580370701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Soltysinska E, Thiele S, Olesen SP, Osadchii OE. Chronic sympathetic activation promotes downregulation of β-adrenoceptor-mediated effects in the guinea pig heart independently of structural remodeling and systolic dysfunction. Pflugers Arch 2011; 462:529-43. [PMID: 21811789 DOI: 10.1007/s00424-011-1005-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 07/25/2011] [Accepted: 07/25/2011] [Indexed: 11/26/2022]
Abstract
It is uncertain if downregulation of β-adrenoceptor signaling pathway is promoted by an enhanced adrenergic tone at an early stage of cardiac disease, or it develops secondary to detrimental local myocardial changes in advanced heart failure. We examined the integrity of β-adrenoceptor signaling pathway upon chronic infusion of isoproterenol, a β-adrenoceptor agonist, at a dose producing no structural left ventricular (LV) remodeling and systolic dysfunction. Subcutaneous isoproterenol infusion (400 μg kg(-1) h(-1) over 16 days) to guinea pigs using osmotic minipumps produced no change in cardiac weights, LV internal dimensions, myocyte cross-sectional area, extent of interstitial fibrosis, and basal contractile function. Isolated, perfused heart preparations from isoproterenol-treated guinea pigs exhibited attenuated responsiveness to acute β-adrenoceptor stimulation, as evidenced by reduced LV developed pressure increase, less shortening of LV epicardial monophasic action potential and effective refractory period, and less myocardial cyclic adenosine monophosphate elevation, in response to isoproterenol exposure, when compared to saline-treated controls. Pharmacological responses to forskolin, an activator of the adenylate cyclase catalytic subunit, were well preserved in isoproterenol-treated hearts. Downregulation of β-adrenoceptor-mediated effects upon chronic isoproterenol infusion was associated with markedly reduced stimulatory G-protein α-subunit (G(sα)) myocardial expression levels. No change in expression levels of β-adrenoceptors, G-protein-coupled receptor kinase 2, inhibitory G-protein α-subunit (G(iα2)), and Ca(v)1.2 and K(v)7.1 ion channels was determined in isoproterenol-treated hearts. We therefore conclude that sustained adrenergic overstimulation may promote downregulation of myocardial β-adrenoceptor-mediated effects independently of structural LV remodeling and systolic failure, an effect attributed to β-adrenoceptor uncoupling from adenylate cyclase due to reduced G(sα)-protein expression.
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Affiliation(s)
- Ewa Soltysinska
- The Danish National Research Foundation Centre for Cardiac Arrhythmia, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, 2200, Copenhagen N, Denmark
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Lampert R, Salberg L, Burg M. Emotional stress triggers symptoms in hypertrophic cardiomyopathy: a survey of the Hypertrophic Cardiomyopathy Association. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2011; 33:1047-53. [PMID: 20487360 DOI: 10.1111/j.1540-8159.2010.02770.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Symptoms are among the most important factors impacting quality of life (QOL) in hypertrophic cardiomyopathy (HCM) patients, and reflect a poor prognosis. Whether emotional stress can trigger symptoms of chest pain, dyspnea, palpitations, and lightheadedness has not been described. METHODS Members of the Hypertrophic Cardiomyopathy Association (HCMA) received an electronic link via e-mail to an ongoing online survey, also accessed via links on the HCMA message-board and homepage. Between May 2007 and November 2008, there were 1,297 respondents. The survey queried demographic and self-reported clinical information, and types and triggers of symptoms. Respondents reported physical and emotional QOL on a 1-10 Likert scale. RESULTS Symptoms reported included chest pain (49%), dyspnea (70%), palpitations (61%), and syncope/lightheadedness (59%). The most common symptom trigger was exertion, 64% describing symptoms while climbing stairs or hills. Forty-nine percent described experiencing symptoms during emotional stress. Those reporting chest pain were more likely to report emotion triggering (60%) than those reporting palpitations, syncope/lightheadedness, or dyspnea (50-54% each). Both physical and emotional QOL were significantly decreased in those describing emotion-triggered symptoms. Women were more likely than men to report symptoms overall, as well as emotion-triggered symptoms (50% vs 35%, P < 0.001) and exertion-triggered symptoms (79% vs 58%, P < 0.001). After controlling for presence of symptoms, both emotion- and exertion-triggered symptoms remained significantly more common in women. CONCLUSIONS Triggering of symptoms by emotion is common in individuals with HCM. Further studies will determine pathways linking emotional stressors with chest pain, dyspnea, palpitations, and lightheadedness in these patients.
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Affiliation(s)
- Rachel Lampert
- Yale University School of Medicine, Department of Internal Medicine, New Haven, CT, USA.
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Jimenez J, Tardiff JC. Abnormal heart rate regulation in murine hearts with familial hypertrophic cardiomyopathy-related cardiac troponin T mutations. Am J Physiol Heart Circ Physiol 2010; 300:H627-35. [PMID: 21131475 DOI: 10.1152/ajpheart.00247.2010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mutations in cardiac troponin T (cTnT), Δ160E and R92Q, have been linked to familial hypertrophic cardiomyopathy (FHC), and some studies have indicated that these mutations can lead to a high incidence of sudden cardiac death in the relative absence of significant ventricular hypertrophy. Alterations in autonomic function have been documented in patients with hypertrophic cardiomyopathy. We hypothesize that alterations in autonomic function may contribute to mutation-specific clinical phenotypes in cTnT-related FHC. Heart rate (HR) variability (HRV) has been used to assess autonomic function from an electrocardiograph. Nontransgenic, Δ160E, or R92Q mice were implanted with radiofrequency transmitters to obtain continuous electrocardiograph recordings during 24-h baseline and 30-min recordings after β-adrenergic receptor drug injections. Although Δ160E mice did not differ from nontransgenic mice for any 24-h HRV measurements, R92Q mice had impaired HR regulation, as measured by a decrease in the SD of the R-R interval, a decrease in the low frequency-to-high frequency ratio, a decrease in normalized low frequency, and an increase in normalized high frequency. β-Adrenergic receptor density measurements and HRV analysis after drug injections did not reveal any significant differences for Δ160E or R92Q mice versus nontransgenic mice. Arrhythmia analysis revealed both an increased incidence of heart block in R92Q mice at baseline and frequency of premature ventricular contractions after isoproterenol injections in Δ160E and R92Q mice. In addition, Δ160E and R92Q mice exhibited a prolonged P duration after drug injections. Therefore, between two independent and clinically severe cTnT mutations within the same functional domain, only R92Q mice exhibited altered autonomic function, whereas both mutations demonstrated abnormalities in conduction and ventricular ectopy.
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Affiliation(s)
- Jesus Jimenez
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, 1300 Morris Park Ave., Ullmann Bldg. 316, Bronx, NY 10803, USA
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Gaemperli O, Liga R, Spyrou N, Rosen SD, Foale R, Kooner JS, Rimoldi OE, Camici PG. Myocardial -adrenoceptor down-regulation early after infarction is associated with long-term incidence of congestive heart failure. Eur Heart J 2010; 31:1722-9. [DOI: 10.1093/eurheartj/ehq138] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Fuster V, van der Zee S, Miller MA. Evolving anatomic, functional, and molecular imaging in the early detection and prognosis of hypertrophic cardiomyopathy. J Cardiovasc Transl Res 2009; 2:398-406. [PMID: 20559998 DOI: 10.1007/s12265-009-9133-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Accepted: 09/21/2009] [Indexed: 12/27/2022]
Abstract
Evolving imaging modalities in hypertrophic cardiomyopathy (HCM), such as tissue Doppler, speckle tracking, measures of myocardial blood flow, and cardiac magnetic resonance with gadolinium enhancement, have advanced our understanding of the pathogenesis of myocardial dysfunction in hypertrophic cardiomyopathy. These modalities have the potential to differentiate HCM from other causes of left ventricular hypertrophy when there is uncertainty about the diagnosis and to identify affected individuals in the pre-clinical phase of the disease process. Furthermore, preliminary data suggests that functional imaging techniques may add incremental value to conventional risk stratification tools to identify individuals at high risk for sudden death or progression to congestive heart failure.
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Affiliation(s)
- Valentin Fuster
- Zena and Michael A. Wiener Cardiovascular Institute, and the Marie-Josee and Henry R. Kravis Cardiovascular Health Center, Mount Sinai Medical Center, The Mount Sinai School of Medicine, New York, NY, 10029, USA.
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Shimizu M, Ino H, Okeie K, Emoto Y, Yamaguchi M, Yasuda T, Fujino N, Fujii H, Fujita S, Nakajima K, Taki J, Mabuchi H. Cardiac sympathetic activity in the asymmetrically hypertrophied septum in patients with hypertension or hypertrophic cardiomyopathy. Clin Cardiol 2009; 23:365-70. [PMID: 10803446 PMCID: PMC6654774 DOI: 10.1002/clc.4960230512] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND In patients with essential hypertension (HT), proportional (symmetric) left ventricular hypertrophy (LVH) is common. In contrast, hypertrophic cardiomyopathy (HCM) is characterized by disproportional LVH and, in particular, asymmetric septal hypertrophy (ASH); however, some hypertensive patients also develop ASH. It has not been determined whether such cases represent a distinct type of hypertensive LVH or HCM combined with hypertension. HYPOTHESIS The study was undertaken to evaluate sympathetic activity in the interventricular septum in patients with HT and ASH or in patients with HCM. METHODS The patients were evaluated by I-123 meta-iodobenzylguanidine (MIBG) and thallium-201 (201Tl) single-photon emission computed tomography (SPECT), respectively. They were divided into three groups: patients with essential HT and symmetric septal hypertrophy (Group A), patients with HT and ASH (Group B), and patients with HCM and ASH (Group C). RESULTS Compared with the lateral wall, early uptake of MIBG in the septum was significantly higher in Group B than in Group A, but not significantly different between Groups A and C. Compared with the lateral wall, early uptake of 201Tl in the septum did not differ among the three groups. No significant difference in the MIBG clearance in the lateral wall was seen among the three groups. By contrast, MIBG clearances in the septum and apex were significantly greater in Group C than in Groups A and B. There was an inverse correlation between systolic thickening and MIBG clearance in the septum. CONCLUSION These findings suggest that sympathetic activity in the septum differs between patients with HT and ASH and patients with HCM.
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Affiliation(s)
- M Shimizu
- The Second Department of Internal Medicine, School of Medicine, Kanazawa University, Japan
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Park-Holohan SJ, Asselin MC, Turton DR, Williams SL, Hume SP, Camici PG, Rimoldi OE. Quantification of [11C]GB67 binding to cardiac alpha1-adrenoceptors with positron emission tomography: validation in pigs. Eur J Nucl Med Mol Imaging 2008; 35:1624-35. [PMID: 18481065 DOI: 10.1007/s00259-008-0805-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2007] [Accepted: 04/05/2008] [Indexed: 11/27/2022]
Abstract
INTRODUCTION An increase in human cardiac alpha(1)-adrenoceptor (alpha(1)-AR) density is associated with various diseases such as myocardial ischemia, congestive heart failure, hypertrophic cardiomyopathy and hypertension. Positron emission tomography (PET) with an appropriate radioligand offers the possibility of imaging receptor function in the normal and diseased heart. [(11)C]GB67, an analogue of prazosin, has been shown in rats to have potential as a PET ligand with high selectivity to alpha(1)-AR. However, alpha(1)-AR density is up to ten times higher in rat heart compared to that in man. The aim of the present preclinical study was to extend the previous evaluation to a large mammal heart, where the alpha(1)-AR density is comparable to man, and to validate a method for quantification before PET studies in man. METHODS Seven [(11)C]GB67 PET studies, with weight-adjusted target dose of either 5.29 MBq kg(-1) (pilot, test-retest and baseline-predose studies) or 8.22 MBq kg(-1) (baseline-displacement studies), were performed in four anaesthetised pigs (39.5 +/- 3.9 kg). Total myocardial volume of distribution (V (T)) was estimated under different pharmacological conditions using compartmental analysis with a radiolabelled metabolite-corrected arterial plasma input function. A maximum possible blocking dose of 0.12 mumol kg(-1) of unlabeled GB67 was given 20 min before [(11)C]GB67 administration in the predose study and 45 min after administration of [(11)C]GB67 in the displacement study. In addition, [(15)O]CO (3,000 MBq) and [(15)O]H(2)O, with weight adjusted target dose of 10.57 MBq kg(-1), were also administered for estimation of blood volume recovery (RC) of the left ventricular cavity and myocardial perfusion (MBF), respectively. RESULTS [(11)C]GB67 V (T) values (in ml cm(-3)) were estimated to be 24.2 +/- 5.5 (range, 17.3-31.3), 10.1 (predose) and 11.6 (displacement). MBF did not differ within each pig, including between baseline and predose conditions. Predose and displacement studies showed that specific binding of [(11)C]GB67 to myocardial alpha(1)-ARs accounts for approximately 50% of V (T). CONCLUSION The present study offers a methodology for using [(11)C]GB67 as a radioligand to quantify human myocardial alpha(1)-ARs in clinical PET studies.
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Affiliation(s)
- So-Jin Park-Holohan
- Hammersmith Imanet Ltd., GE HealthCare, Cyclotron Building, Hammersmith Hospital, Du Cane Road, London, UK
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Abstract
The aberrant expression and function of certain receptors in tumours and other diseased tissues make them preferable targets for molecular imaging. PET and SPECT radionuclides can be used to label specific ligands with high affinity for the target receptors. The functional information obtained from imaging these receptors can be used to better understand the systems under investigation and for diagnostic and therapeutic applications. This review discusses some of the aspects of receptor imaging with small molecule tracers by PET and SPECT and reviews some of the tracers for the receptor imaging of tumours and brain, heart and lung disorders.
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Affiliation(s)
- Aviv Hagooly
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., Campus Box 8225, St. Louis, MO 63110, USA.
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John AS, Mongillo M, Depre C, Khan MT, Rimoldi OE, Pepper JR, Dreyfus GD, Pennell DJ, Camici PG. Pre- and post-synaptic sympathetic function in human hibernating myocardium. Eur J Nucl Med Mol Imaging 2007; 34:1973-80. [PMID: 17661029 DOI: 10.1007/s00259-007-0507-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Accepted: 06/11/2007] [Indexed: 01/08/2023]
Abstract
PURPOSE Impaired pre-synaptic noradrenaline uptake-1 mechanism has been reported in a swine model of hibernating myocardium (HM). To ascertain whether adrenergic neuroeffector abnormalities are present in human HM, we combined functional measurements in vivo using cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) to assess pre- and post-synaptic sympathetic function. METHODS Twelve patients with coronary artery disease and chronic left ventricular (LV) dysfunction underwent CMR at baseline and 6 months after bypass for assessment of regional and global LV function and identification of segments with reversible dysfunction. Before surgery, myocardial noradrenaline uptake-1 ([(11)C]meta-hydroxy-ephedrine; HED) and beta-adrenoceptor (beta-AR) density ([(11)C]CGP-12177) were measured with PET. Patient PET data were compared with those in 18 healthy controls. RESULTS The volume of distribution (V(d)) of HED in HM (47.95+/-28.05 ml/g) and infarcted myocardium (42.69+/-25.76 ml/g) was significantly reduced compared with controls (66.09+/-14.48 ml/g). The V(d) of HED in normal myocardium (49.93+/-20.48 ml/g) of patients was also lower than that in controls and the difference was close to statistical significance (p=0.06). Myocardial beta-AR density was significantly lower in HM (5.49+/-2.35 pmol/g), infarcted (4.82+/-2.61 pmol/g) and normal (5.86+/-1.81 pmol/g) segments of patients compared with healthy controls (8.61+/-1.32 pmol/g). CONCLUSION Noradrenaline uptake-1 mechanism and beta-AR density are reduced in the myocardium of patients with chronic LV dysfunction and evidence of HM. The increased sympathetic activity to the heart in these patients is a generalised rather than regional phenomenon which is likely to contribute to the remodelling process of the whole LV rather than playing a causative role in HM.
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Affiliation(s)
- Anna S John
- National Heart and Lung Institute, Imperial College, Hammersmith Hospital, Du Cane Road, London, UK
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21
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Salinas C, Muzic RF, Ernsberger P, Saidel GM. Robust experiment design for estimating myocardial beta adrenergic receptor concentration using PET. Med Phys 2007; 34:151-65. [PMID: 17278500 DOI: 10.1118/1.2402585] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Myocardial beta adrenergic receptor (beta-AR) concentration can substantially decrease in congestive heart failure and significantly increase in chronic volume overload, such as in severe aortic valve regurgitation. Positron emission tomography (PET) with an appropriate ligand-receptor model can be used for noninvasive estimation of myocardial beta-AR concentration in vivo. An optimal design of the experiment protocol, however, is needed for sufficiently precise estimates of beta-AR concentration in a heterogeneous population. Standard methods of optimal design do not account for a heterogeneous population with a wide range of beta-AR concentrations and other physiological parameters and consequently are inadequate. To address this, we have developed a methodology to design a robust two-injection protocol that provides reliable estimates of myocardial beta-AR concentration in normal and pathologic states. A two-injection protocol of the high affinity beta-AR antagonist [18F]-(S)-fluorocarazolol was designed based on a computer-generated (or synthetic) population incorporating a wide range of beta-AR concentrations. Timing and dosage of the ligand injections were optimally designed with minimax criterion to provide the least bad beta-AR estimates for the worst case in the synthetic population. This robust experiment design for PET was applied to experiments with pigs before and after beta-AR upregulation by chemical sympathectomy. Estimates of beta-AR concentration were found by minimizing the difference between the model-predicted and experimental PET data. With this robust protocol, estimates of beta-AR concentration showed high precision in both normal and pathologic states. The increase in beta-AR concentration after sympathectomy predicted noninvasively with PET is consistent with the increase shown by in vitro assays in pig myocardium. A robust experiment protocol was designed for PET that yields reliable estimates of beta-AR concentration in a population with normal and pathologic states. This methodology is applicable in general to optimal estimation of parameters in heterogeneous populations.
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Affiliation(s)
- Cristian Salinas
- Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106, USA
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22
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Nagueh SF, Mahmarian JJ. Noninvasive cardiac imaging in patients with hypertrophic cardiomyopathy. J Am Coll Cardiol 2006; 48:2410-22. [PMID: 17174177 DOI: 10.1016/j.jacc.2006.07.065] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2006] [Revised: 06/28/2006] [Accepted: 07/30/2006] [Indexed: 01/24/2023]
Abstract
Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiomyopathy and the most common cause of cardiac death in young athletes in the U.S. Noninvasive imaging plays an important role in detecting the disease, understanding its pathophysiology, and selecting as well as guiding appropriate therapy. In this review, we discuss the existing methodology with emphasis on current and emerging clinical applications in patients with HCM.
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Affiliation(s)
- Sherif F Nagueh
- Department of Cardiology, The Methodist DeBakey Heart Center, The Methodist Hospital, Houston, Texas 77030, USA.
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23
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Rimoldi OE, Drake-Holland AJ, Noble MIM, Camici PG. Basal and hyperaemic myocardial blood flow in regionally denervated canine hearts: an in vivo study with positron emission tomography. Eur J Nucl Med Mol Imaging 2006; 34:197-205. [PMID: 16951953 DOI: 10.1007/s00259-006-0233-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Accepted: 07/03/2006] [Indexed: 12/21/2022]
Abstract
PURPOSE Positron emission tomography (PET) studies in patients with diabetic autonomic neuropathy (DAN) have demonstrated the impact of this disease on cardiac sympathetic innervation and myocardial blood flow (MBF). To investigate the effects of selective partial sympathetic denervation of the left ventricle (LV) on baseline and hyperaemic MBF, we measured myocardial presynaptic catecholamine re-uptake (uptake-1), beta-adrenoceptor (beta-AR) density and MBF non-invasively by means of PET in a canine model of regional sympathetic denervation. METHODS In 11 anaesthetised dogs, the sympathetic nerves of the free wall and septum of the LV were removed by means of dissection and phenol painting. Three weeks later, the animals were studied with PET. MBF was measured at baseline and following i.v. adenosine (140 microg kg(-1) min(-1)) and dobutamine (20 microg kg(-1) min(-1)) using(15)O-labelled water. Sympathetic denervation was confirmed by an 80+/-12% decrease in the volume of distribution (V(d)) of [(11)C]hydroxyephedrine (HED) compared with innervated regions. Myocardial beta-AR density was measured using [(11)C]CGP12177. RESULTS Innervated and denervated regions showed no differences in MBF at baseline and during adenosine or dobutamine. [(11)C]HED V(d)was inversely correlated with MBF in both regions at baseline, and the correlation was lost during hyperaemia in denervated regions. However, for any given value of MBF, [(11)C]HED V(d)was significantly lower in the denervated regions. beta-AR density was comparable in denervated and innervated regions (17.9+/-4.2 vs 18.4+/-3.3 pmol g(-1); p=NS). CONCLUSION In this experimental model, selective, regional sympathetic denervation of the LV, which results in a profound reduction in [(11)C]HED V(d), did not affect baseline or hyperaemic MBF. In addition, we demonstrated that, under baseline conditions, there was a significant inverse correlation between [(11)C]HED V(d)and MBF in both denervated and innervated regions.
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Affiliation(s)
- Ornella E Rimoldi
- MRC Clinical Sciences Centre, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK
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Nishijima KI. A Study on the Highly Efficient Synthesis and Pharmaceutical Evaluation of PET Radiopharmaceuticals for the Clinical Application. YAKUGAKU ZASSHI 2006; 126:737-45. [PMID: 16946587 DOI: 10.1248/yakushi.126.737] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Positron Emission Tomography (PET) is an advanced non-invasive technology used in the field of nuclear medicine for clinical diagnosis using radiotracers labeled with short-lived positron emitting radionuclides such as (11)C (half-life: 20.4 min), (13)N, (15)O and (18)F. The present study describes an efficient rapid synthesis method for [(11)C]Phosgene ([(11)C]COCl(2)) which is an important potential precursor for preparation of PET radiopharmaceuticals. Catalytic oxidation of [(11)C]CCl(4) using Fe(2)O(3) powder mixed with Fe granules as an oxidizing agent was newly accomplished with a development of fully automated synthetic apparatus. Utilization of produced [(11)C]COCl(2) provided a substantial synthesis of [2-(11)C]thymine as a key intermediate for preparation of [2-(11)C]thymidine, a PET tracer to evaluate cellular proliferation. Direct ring closure reaction of the alkali metal salt of beta-(N-benzoyl-amino)methacrylamide with [(11)C]COCl(2) readily proceeded under mild conditions to afford [2-(11)C]thymine in fair yield reproducibly. By way of further application, a useful PET ligand for beta-adrenoreceptors, S-(-)-[(11)C]CGP-12177 (CGP) was synthesized in markedly high yield with high specific activity and radiochemical purity. CGP for intravenous injection was prepared in 25 min after EOB with a yield of 1.5+/-0.2 GBq. These results of quality control tests demonstrated that CGP preparation is suitable for routine clinical use. Thus, CGP-PET study has been newly added to clinical PET for cardiac functional investigation in Hokkaido University Hospital.
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Affiliation(s)
- Ken-ichi Nishijima
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Japan.
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Nishijima K, Kuge Y, Seki K, Ohkura K, Morita K, Nakada K, Tamaki N. Preparation and pharmaceutical evaluation for clinical application of high specific activity S-(-)[11C]CGP-12177, a radioligand for beta-adrenoreceptors. Nucl Med Commun 2005; 25:845-9. [PMID: 15266181 DOI: 10.1097/01.mnm.0000134320.39903.75] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Although S-(-)[C]CGP-12177 is a useful positron emission tomography (PET) ligand for beta-adrenoreceptors, the difficulty in radiolabelling the compound has prevented its extensive clinical application. Recently, we have developed a simple synthesis method for S-(-)[C]CGP-12177. In the present study, we attempted to prepare S-(-)[C]CGP-12177 with a high specific activity for intravenous injection which is feasible for the clinical evaluation of beta-adrenoreceptors. METHODS The [C]methane produced during irradiation of a N2--H2 (95/5) mixture with an 18 MeV proton beam (20 microA, 30 min) was chlorinated using Cl2 to yield [C]carbon tetrachloride. S-(-)[C]CGP-12177 was synthesized by reacting the diamino precursor with [C]phosgene produced by oxidizing [C]carbon tetrachloride on a Fe--Fe2O3 column. The product was purified by using reversed phase, high-performance liquid chromatography (RP-HPLC) and the radioactive fraction containing S-(-)[C]CGP-12177 was collected and evaporated to dryness. S-(-)[C]CGP-12177 dissolved in physiological saline was sterilized through a 0.22 microm membrane filter. The radiochemical purity and the mass of the compound were determined with RP-HPLC. The residual organic solvents were determined with GC. Tests for sterility and the presence of bacterial endotoxins were also performed. RESULTS S-(-)[C]CGP-12177 for intravenous injection was prepared in 25 min after the end of bombardment with a yield of 1.5+/-0.2 GBq. Specific activity was found to be 385.4+/-133.0 GBq/ micromol at the end of synthesis (EOS) (n=3). Radiochemical purity was found to be more than 99%. Toluene was not detected in the solution. The ethanol concentration was determined to be 60.3+/-52.5 ppm. Tests for sterility and bacterial endotoxins showed negative results. CONCLUSION We successfully prepared S-(-)[C]CGP-12177 formulated for intravenous injection with high purity and high specific activity, which is feasible for the clinical evaluation of beta-adrenoreceptors.
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Affiliation(s)
- K Nishijima
- Department of Tracer Kinetics and Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
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Mörner S, Wiklund U, Rask P, Olofsson BO, Kazzam E, Waldenström A. Parasympathetic dysfunction in hypertrophic cardiomyopathy assessed by heart rate variability: comparison between short-term and 24-h measurements. Clin Physiol Funct Imaging 2005; 25:90-9. [PMID: 15725307 DOI: 10.1111/j.1475-097x.2004.00595.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In this study, we evaluate cardiac autonomic function in hypertrophic cardiomyopathy (HCM) by assessing heart rate variability (HRV), comparing a short-term laboratory method with an ambulatory (24-h) method, in patients with and without beta-blockade. Reduced HRV is a risk factor for adverse events in some cardiac diseases, but is not a proven risk indicator in HCM. Analysis of HRV has been based on either short- or long-term electrocardiographic recordings and previous studies in HCM have shown conflicting results. There is no consensus on which method to prefer, and we evaluate, for the first time, both short- and long-term analyses in patients with HCM. Long- and short-term HRV analyses were performed in 43 patients with HCM. They were divided in two groups, 22 patients on beta-blockade and 21 non-treated patients. As controls, 121 healthy subjects were used. Young patients without beta-blockade showed a reduction in HRV parameters reflecting parasympathetic function, both in the short- and long-term registrations, which was attenuated by beta-blockade. Parasympathetic autonomic regulation was found to be impaired in young patients with HCM. This may be of clinical relevance as abnormal autonomic function might be a substrate for malignant dysrhythmias. The impairment was attenuated by beta-blockade, which might indicate a clinically useful effect. We also show that short- and long-term methods yield similar results, suggesting that a short-term registration might be sufficient to assess HRV in patients with HCM.
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Affiliation(s)
- Stellan Mörner
- Department of Medicine, University Hospital, Umeå, Sweden.
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Elsinga PH, van Waarde A, Vaalburg W. Receptor imaging in the thorax with PET. Eur J Pharmacol 2005; 499:1-13. [PMID: 15363946 DOI: 10.1016/j.ejphar.2004.06.057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2004] [Revised: 06/23/2004] [Accepted: 06/29/2004] [Indexed: 10/26/2022]
Abstract
This review focuses on positron emission tomography (PET)-imaging of receptors in the sympathetic and the parasympathetic systems of heart and lung and highlights the human applications of PET. For the alpha-adrenoceptor, only [11C]GB67 (N2-[6-[(4-amino-6,7-dimethoxy-2-quinazolinyl)(methyl)amino]hexyl]-N2-[11C]methyl-2-furamide hydrochloride) has been developed. Its potential for application in patients needs to be assessed. For both the beta-adrenergic and the muscarinic systems, potent PET radioligands have been prepared and evaluated in patients. It has been possible to measure receptor densities quantitatively in human heart [[11C]MQNB: [11C]methylquinuclidinyl benzilate, [11C]CGP12177: S-(3'-t-butylamino-2'-hydroxypropoxy)-benzimidazol-2-[11C]one and [11C]CGP12388: (S)-4-(3-(2'-[11C]isopropylamino)-2-hydroxypropoxy)-2H-benzimidazol-2-one] and qualitatively in lung [[11C]VC002: N-[11C]-methyl-piperidin-4-yl-2-cyclohexyl-2-hydroxy-2-phenylacetate and [11C]CGP12177]. Besides these subtype nonselective radioligands, the development of compounds that are selective for one subtype are ongoing and have not found successful application in humans yet.
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Affiliation(s)
- Philip H Elsinga
- Groningen University Hospital, PET-center, P.O. Box 30001, 9700 RB Groningen, The Netherlands.
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Kumar R, Jana S. Positron emission tomography: an advanced nuclear medicine imaging technique from research to clinical practice. Methods Enzymol 2004; 385:3-19. [PMID: 15130730 DOI: 10.1016/s0076-6879(04)85001-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Rakesh Kumar
- Department of Nuclear Medicine, All India Institute of Medical Sciences, NewDelhi 110029, India
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Verrier RL, Tolat AV, Josephson ME. T-Wave alternans for arrhythmia risk stratification in patients with idiopathic dilated cardiomyopathy. J Am Coll Cardiol 2003; 41:2225-7. [PMID: 12821252 DOI: 10.1016/s0735-1097(03)00466-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Spyrou N, Rosen SD, Fath-Ordoubadi F, Jagathesan R, Foale R, Kooner JS, Camici PG. Myocardial beta-adrenoceptor density one month after acute myocardial infarction predicts left ventricular volumes at six months. J Am Coll Cardiol 2002; 40:1216-24. [PMID: 12383568 DOI: 10.1016/s0735-1097(02)02162-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To investigate whether myocardial beta-adrenoceptor (beta-AR) downregulation precedes and predicts left ventricular (LV) dilation after acute myocardial infarction (AMI), we measured beta-AR density within four weeks of AMI and correlated it with serial measurements of LV volumes. BACKGROUND Patients who develop heart failure following AMI have an increased sympathetic drive to the heart within the first four weeks after infarction. METHODS We prospectively studied 61 patients in whom AMI was the first presentation of coronary artery disease (CAD) and with no signs of heart failure. The LV volumes were measured one, three, and six months after AMI by echocardiography. Beta-AR density was measured using positron emission tomography with S-[(11)C]CGP 12177. Seventeen matched healthy volunteers served as controls. RESULTS Whole heart beta-AR density was lower in patients than in controls (6.25 +/- 0.98 pmol/g vs. 8.32 +/- 2.14 pmol/g, p < 0.0001). In patients, beta-AR density was inversely correlated with end-systolic and end-diastolic volumes six months after AMI. Patients whose LV was dilated at six months had a lower beta-AR density in noninfarcted myocardium than patients without dilation (6.15 pmol/g vs. 6.98 pmol/g, p = 0.008). In addition, beta-AR density in noninfarcted myocardium was higher when the infarct-related artery was patent (6.87 +/- 1.14 pmol/g vs. 5.76 +/- 0.86 pmol/g occluded, p < 0.01). CONCLUSIONS Myocardial beta-AR density is reduced after AMI in the absence of heart failure, and the reduction predicts later LV dilation. These data are suggestive of an enhanced sympathetic drive to the heart, having an important etiologic role in LV remodeling after AMI.
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Affiliation(s)
- Nicos Spyrou
- Medical Research Council Clinical Sciences Centre and National Heart and Lung Institute, Faculty of Medicine, Imperial College, London, United Kingdom
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31
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Narita M, Kurihara T. Scintigraphic assessment of patients with electrocardiographic left ventricular hypertrophy with ST-T changes without apparent cause. Clin Nucl Med 2002; 27:641-7. [PMID: 12192282 DOI: 10.1097/00003072-200209000-00007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Some patients who show electrocardiographic left ventricular hypertrophy with ST-T changes (ECG-LVH) are difficult to evaluate using routine examinations. To clarify the pathologic process in these patients, the authors performed several scintigraphic examinations. MATERIALS AND METHODS Twenty-nine patients with ECG-LVH, without apparent cause, such as left ventricular (LV) systolic overloading or increased LV mass, were examined by myocardial I-123 MIBG imaging, I-123 BMIPP imaging, and exercise-induced stress perfusion imaging. In addition to the visual assessment of each image, we calculated global and regional myocardial washout of I-123 MIBG (%washout). The LV was assessed using conventional echocardiography. RESULTS Visually observed abnormalities were located exclusively at the LV apex with all imaging methods and were detected in 76%, 52%, and 17% of patients by I-123 MIBG, I-123 BMIPP, and perfusion imaging, respectively. A follow-up study revealed that the apical defects of I-123 MIBG were subsequently followed by defects of I-123 BMIPP and then perfusion abnormalities. In patients with an apical defect revealed by I-123 MIBG imaging, apical %washout was high. In nine patients who underwent myocardial biopsy, myocardial disarray was observed at the apical regions. CONCLUSIONS In many patients with ECG-LVH without apparent cause, sympathetic abnormalities are observed at the apex, similar to pathologic changes in hypertrophic cardiomyopathy. These abnormalities may lead to changes in fatty acid metabolism and perfusion.
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Schäfers M, Riemann B, Levkau B, Wichter T, Schäfers K, Kopka K, Breithardt G, Schober O. Current status and future applications of cardiac receptor imaging with positron emission tomography. Nucl Med Commun 2002; 23:113-5. [PMID: 11891463 DOI: 10.1097/00006231-200202000-00001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Dutka DP, Camici PG. The contribution of positron emission tomography to the study of ischemic heart failure. Prog Cardiovasc Dis 2001; 43:399-418. [PMID: 11251127 DOI: 10.1053/pcad.2001.20673] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cardiac imaging with positron emission tomography offers unrivaled sensitivity and specificity to probe cardiovascular physiology in health and disease. The use of positron emission tomography to noninvasively measure regional myocardial blood flow and assess myocardial viability in patients with ventricular dysfunction and coronary artery disease has contributed greatly to our understanding of the pathophysiology of ischemic heart failure. The advances and the need for further studies to establish both the natural history of such ventricular dysfunction and the role of coronary revascularization are discussed.
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Affiliation(s)
- D P Dutka
- MRC Clinical Sciences Centre, Imperial College School of Medicine, London, England
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35
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Schotten U, Filzmaier K, Borghardt B, Kulka S, Schoendube F, Schumacher C, Hanrath P. Changes of beta-adrenergic signaling in compensated human cardiac hypertrophy depend on the underlying disease. Am J Physiol Heart Circ Physiol 2000; 278:H2076-83. [PMID: 10843907 DOI: 10.1152/ajpheart.2000.278.6.h2076] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In human heart failure, desensitization of the beta-adrenergic signal transduction has been reported to be one of the main pathophysiological alterations. However, data on the beta-adrenergic system in human compensated cardiac hypertrophy are very limited. Therefore, we studied the myocardial beta-adrenergic signaling in patients suffering from hypertrophic obstructive cardiomyopathy (HOCM, n = 9) or from aortic valve stenosis (AoSt, n = 8). beta-Adrenoceptor density determined by [(125)I]iodocyanopindolol binding was reduced in HOCM and AoSt compared with nonhypertrophied, nonfailing myocardium (NF) of seven organ donors. In HOCM the protein expression of stimulatory G protein alpha-subunit (G(s)alpha) measured by immunoblotting was unchanged, whereas the inhibitory G protein alpha-subunit (Galpha(i-2)) was increased. In contrast, in AoSt, Galpha(i-2) protein was unchanged, but G(s)alpha protein was increased. Adenylyl cyclase stimulation by isoproterenol was reduced in HOCM but not in AoSt. Plasma catecholamine levels were normal in all patients. In conclusion, both forms of hypertrophy are associated with beta-adrenoceptor downregulation but with different changes at the G protein level that occur before symptomatic heart failure due to progressive dilatation of the left ventricle develops and are not due to elevated plasma catecholamine levels.
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Affiliation(s)
- U Schotten
- Department of Cardiology, University Hospital Aachen, Germany.
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36
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Pike VW, Law MP, Osman S, Davenport RJ, Rimoldi O, Giardinà D, Camici PG. Selection, design and evaluation of new radioligands for PET studies of cardiac adrenoceptors. PHARMACEUTICA ACTA HELVETIAE 2000; 74:191-200. [PMID: 10812957 DOI: 10.1016/s0031-6865(99)00032-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Changes in the numbers of human cardiac adrenoceptors (ARs) are associated with various diseases, such as myocardial ischemia, congestive heart failure, cardiomyopathy and hypertension. There is a clear need for capability to assess human cardiac ARs directly in vivo. Positron emission tomography (PET) is an imaging technique that provides this possibility, if effective radioligands can be developed for the targeted ARs. Here, the status of myocardial AR radioligand development for PET is described. Currently, there exist effective radioligands for imaging beta-ARs in human myocardium. One of these, [11C](S)-CGP 12177, is applied extensively to clinical research with PET, sometimes with other tracers of other aspects of the noradrenalin system. Alternative radioligands are in development for beta-ARs, including beta 1-selective radioligands. A promising radioligand for imaging myocardial alpha 1-ARs, [11C]GB67, is now being evaluated in human PET experiments.
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Affiliation(s)
- V W Pike
- MRC Cyclotron Unit, Imperial College School of Medicine, Hammersmith Hospital, London, UK.
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37
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Valette H, Dollé F, Guenther I, Demphel S, Rasetti C, Hinnen F, Fuseau C, Crouzel C. Preliminary evaluation of 2-[4-[3-tert-butylamino)-2-hydroxypropoxy]phenyl]-3-methyl-6-me thoxy-4(3H)-quinazolinone ([+/-]HX-CH 44) as a selective beta1-adrenoceptor ligand for PET. Nucl Med Biol 1999; 26:105-9. [PMID: 10096509 DOI: 10.1016/s0969-8051(98)00073-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
(+/-)-3-[11C]Methyl-2-[4-[3-(tert-butylamino)-2-hydroxypropoxy]phenyl]-6 -methoxy-4(3H) quinazolinone ([+/-]-[11C]HX-CH 44) was labeled with carbon-11 using [11C]iodomethane with the corresponding N-demethylated precursor. Then, 30-90 mCi (1.10-3.33 GBq) of pure [11C]HX-CH 44 were obtained 30 min after end of bombardment with specific radioactivities of 500-1,400 mCi/micromol (18.5-51.8 GBq/micromol). Myocardial uptake in dogs was 0.340+/-0.043 pmol/mL tissue per nanomole injected, 10-15 min postinjection. Heart-to-lung ratio was 3 from the 5th to the 30th minute. Only 35% of the myocardial radioactivity could be displaced. Tissue uptake could not be blocked with appropriate compounds. Therefore, (+/-)-[11C]HX-CH 44 does not appear to be a suitable ligand for the study of myocardial beta1-adrenoceptors in positron emission tomography.
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Affiliation(s)
- H Valette
- Department de Recherche Medicale, Service Hospitalier Frederic Joliot, Orsay, France
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38
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Omodani H, Kinugawa T, Ogino K, Furuse Y, Yamaguchi M, Mori M, Endo A, Kato M, Kato T, Osaki S, Miyakoda H, Igawa O, Hisatome I, Shigemasa C. Augmented exercise plasma noradrenaline with impaired chronotropic responsiveness in patients with hypertrophic cardiomyopathy. Clin Exp Pharmacol Physiol 1998; 25:1018-23. [PMID: 9888000 DOI: 10.1111/j.1440-1681.1998.tb02177.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1. There is controversy regarding plasma catecholamine levels in patients with hypertrophic cardiomyopathy (HCM) and few data exist on serial plasma catecholamine measurements during exercise. The present study determined whether cardiovascular and plasma catecholamine responses to exercise were altered in patients with HCM. 2. Plasma noradrenaline (NA) and adrenaline were measured at rest, at the end of each stage during exercise and immediately and 5 min after submaximal treadmill exercise in 15 patients with non-obstructive HCM (13 males, two females; mean (+/- SEM) age 54 +/- 3 years) and in 15 age- and sex-matched controls. The ratio of the increment in heart rate (HR) divided by the increment in plasma NA during exercise (delta HR/delta NA) was used as an index of chronotropic sympathetic responsiveness to exercise. 3. Exercise duration was shorter (11.2 +/- 0.6 vs 8.7 +/- 0.6 min for control vs HCM, respectively; P < 0.01) and diastolic blood pressure was significantly higher at stages I and II of modified Bruce protocol HCM. 4. Resting plasma NA levels (149 +/- 17 vs 167 +/- 28 pg/mL for control vs HCM, respectively; NS) were not different, but plasma NA levels at stages I and II were significantly higher in HCM than in controls (243 +/- 26 vs 399 +/- 69 pg/mL (P < 0.05) and 308 +/- 30 vs 548 +/- 110 pg/mL (P < 0.05), respectively). 5. Peak plasma NA levels were not significantly higher in HCM than in controls (578 +/- 59 vs 918 +/- 184 pg/mL, respectively; NS). 6. The ratio delta HR/delta NA was significantly lower in HCM compared with control at stages I and II (0.49 +/- 0.10 vs 0.21 +/- 0.05 (P < 0.05) and 0.38 +/- 0.06 vs 0.20 +/- 0.05 (P < 0.05), respectively). There were no differences in plasma adrenaline responses during exercise between the two groups. 7. Patients with HCM had augmented plasma NA levels during submaximal exercise with a higher diastolic blood pressure response. Chronotropic sympathetic responsiveness was impaired during the early stages of exercise in patients with HCM.
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Affiliation(s)
- H Omodani
- 1st Department of Internal Medicine, Tottori University School of Medicine, Yonago, Japan
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39
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Schäfers M, Lerch H, Wichter T, Rhodes CG, Lammertsma AA, Borggrefe M, Hermansen F, Schober O, Breithardt G, Camici PG. Cardiac sympathetic innervation in patients with idiopathic right ventricular outflow tract tachycardia. J Am Coll Cardiol 1998; 32:181-6. [PMID: 9669268 DOI: 10.1016/s0735-1097(98)00213-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVES This study investigated the neuronal reuptake of norepinephrine (uptake-1) and the beta-adrenoceptor density in patients with idiopathic right ventricular outflow tract tachycardia (RVO-VT). BACKGROUND Clinical findings, such as the inducibility of ventricular tachycardia by stress or catecholamine infusion, and the therapeutic efficacy of antiarrhythmic drugs with antiadrenergic properties suggest abnormalities of cardiac sympathetic innervation in patients with idiopathic RVO-VT. METHODS Eight patients with idiopathic RVO-VT and a total of 29 age-matched control subjects were investigated by positron emission tomography using [11C]hydroxyephedrine (HED) (volume of distribution of [11C]HED) to assess presynaptic norepinephrine reuptake; [11C]CGP 12177 (maximal binding capacity of [11C]CGP 12177) to measure postsynaptic beta-adrenoceptor density; and oxygen-15-labeled water for quantification of myocardial blood flow (MBF). RESULTS Both myocardial catecholamine reuptake and beta-adrenoceptor density were significantly reduced in patients with idiopathic RVO-VT. The volume of distribution of [11C]HED in patients with RVO-VT was (mean +/- SD) 41.0 +/- 13.5 versus 71.0 +/- 18.8 ml/g in control subjects (p < 0.002). The maximal binding capacity of the beta-adrenoceptor antagonist [11C] CGP 12177 was 6.8 +/- 1.2 pmol/g in patients with RVO-VT versus 10.2 +/- 2.9 pmol/g in control subjects (p < 0.004). There were no significant differences in MBF at rest (0.98 +/- 0.14 vs. 0.97 +/- 0.24 ml/min per g, p = NS) between patients with RVO-VT and control subjects. CONCLUSIONS The findings of the present study suggest that myocardial beta-adrenoceptor downregulation in patients with RVO-VT occurs subsequently to increased local synaptic catecholamine levels caused by impaired catecholamine reuptake.
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Affiliation(s)
- M Schäfers
- Department of Nuclear Medicine, Institute for Arteriosclerosis Research, Westfälische Wilhelms University, Munster, Germany
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40
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van Waarde A, Elsinga PH, Doze P, Heldoorn M, Jaeggi KA, Vaalburg W. A novel beta-adrenoceptor ligand for positron emission tomography: evaluation in experimental animals. Eur J Pharmacol 1998; 343:289-96. [PMID: 9570478 DOI: 10.1016/s0014-2999(97)01528-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Myocardial and pulmonary beta-adrenoceptors can be imaged and quantified with the antagonist (S)-4-[3[(1,1-dimethylethyl)amino]-2-hydroxypropoxy]-1,3-dihydro-2H-b enzimidazol-2-[11C]-one (S-[11C]CGP-12177). The synthesis of this ligand (based on the reaction of a precursor with [11C]phosgene) is laborious and in many centers the final product has a low and variable specific activity. This prevents widespread use of S-[11C]CGP-12177 for studies in patients. We prepared S-[11C]CGP-12388, the isopropyl analogue of CGP-12177, by a reliable one-pot procedure and evaluated the radiopharmaceutical for beta-adrenoceptor imaging. Blocking experiments with subtype-selective beta-adrenergic drugs showed that myocardial and pulmonary uptake of S-[11C]CGP-12388 in anesthetized rats reflects ligand binding to beta1- and beta2-adrenoceptors. In this animal model, clearance, metabolism and tissue/plasma ratios of S-[11C]CGP-12388 were similar to those of S-[11C]CGP-12177. A [18F]fluoroisopropyl analogue of CGP-12177 showed less favorable characteristics. S-[11C]CGP-12388 was therefore selected for evaluation in humans and it may become the tracer of choice for clinical studies since it is easily prepared.
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Affiliation(s)
- A van Waarde
- Positron Emission Tomography Center, University Hospital, Groningen, The Netherlands
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41
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Schäfers M, Dutka D, Rhodes CG, Lammertsma AA, Hermansen F, Schober O, Camici PG. Myocardial presynaptic and postsynaptic autonomic dysfunction in hypertrophic cardiomyopathy. Circ Res 1998; 82:57-62. [PMID: 9440705 DOI: 10.1161/01.res.82.1.57] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Although hypertrophic cardiomyopathy (HCM) is genetically determined, several other factors, including autonomic dysfunction, may play a role in the phenotypic expression. A recent study using positron emission tomography with [11C]CGP 12177 ([11C]CGP) demonstrated that beta-adrenoceptor (betaAR) density is reduced in HCM and is correlated with disease progression. This present study tested the hypothesis that this downregulation is associated with reduced catecholamine reuptake (uptake 1) by myocardial sympathetic nerve terminals leading to increased local norepinephrine concentration. Myocardial presynaptic catecholamine reuptake was assessed by measuring the volume of distribution (Vd) of the catecholamine analogue [11C]hydroxyephedrine ([11C]HED) in 9 unrelated HCM patients aged 45+/-15 years. The maximum number of binding sites (Bmax) for myocardial betaAR density was measured in 13 unrelated HCM patients aged 40+/-12 years using the nonselective beta blocker [11C]CGP. Six patients were studied with both [11C]HED and [11C]CGP. Comparison was made with two groups of healthy control subjects for each ligand ([11C]HED, n=10, aged 35+/-8 years; [11C]CGP, n=19, aged 44+/-16 years). Myocardial Vd of [11C]HED (33.4+/-4.3 mL/g tissue) and betaAR density (7.3+/-2.6 pmol/g tissue) were significantly reduced in HCM patients compared with control subjects (71.0+/-18.8 mL/g tissue, P<.001, and 10.2+/-2.9 pmol/g tissue, P=.008, respectively). These results are consistent with our hypothesis that myocardial betaAR downregulation in HCM is associated with an impaired uptake-1 mechanism and hence increased local catecholamine levels.
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Affiliation(s)
- M Schäfers
- Department of Nuclear Medicine, University of Münster, Germany
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42
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Elsinga PH, van Waarde A, Jaeggi KA, Schreiber G, Heldoorn M, Vaalburg W. Synthesis and evaluation of (S)-4-(3-(2'-[11C]isopropylamino)-2-hydroxypropoxy) -2H-benzimidazol -2-one ((S)-[11C]CGP 12388) and (S)-4-(3-((1'-[18F]-fluoroisopropyl)amino)-2-hydroxypropoxy) -2H- benzimidazol-2-one ((S)-[18F]fluoro-CGP 12388) for visualization of beta-adrenoceptors with positron emission tomography. J Med Chem 1997; 40:3829-35. [PMID: 9371248 DOI: 10.1021/jm970267h] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The beta-adrenoceptor antagonist (S)-[11C]CGP 12177 (4-(3-(tert-butylamino)-2-hydroxypropoxy)-2H-benzimidazol -2[11C]- one) is a generally accepted radioligand for cardiac and pulmonary PET studies. The synthesis of [11C]CGP 12177 is a laborious and often troublesome procedure. Therefore, (S)-CGP 12388 (4-(3-(isopropylamino)-2-hydroxypropoxy) -2H-benzimidazol-2-one), 5, the isopropyl analogue of CGP 12177, has been labeled with carbon-11 in the isopropyl group via a reductive alkylation by [11C]acetone (3) of the corresponding (S)-desisopropyl compound 2. The fluoro-substituted analogue of (S)-CGP 12388 was prepared by reacting 2 with [18F]fluoroacetone (4). (S)-[11C]CGP 12388 (5) was easily prepared via a one-pot procedure. The radiochemical yield of (S)-[11C]CGP 12388 (600-800 Ci/mmol, EOS) was 18% (EOB) with a total synthesis time of 35 min, whereas (S)-[18F]fluoro-CGP 12388 (6) (> 2000 Ci/mmol, EOS) was synthesized in 105 min with a radiochemical yield of 12% (EOB). Biodistribution studies in rats demonstrated specific binding to beta-adrenoceptors of (S)-[18F]fluoro-CGP 12388 and (S)-[11C]CGP 12388 in lung and heart. The lungs were clearly visualized with PET studies of rats. Total/nonspecific binding at 60 min postinjection was 5.6 for (S)-[11C]CGP 12388 and 2.0 for the (S)-18F compound. Due to its facile synthetic procedure and in vivo data, (S)-[11C]CGP 12388 is a promising beta-adrenoceptor ligand for clinical PET.
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Affiliation(s)
- P H Elsinga
- PET-center, University Hospital Groningen, The Netherlands.
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43
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Qing F, Rahman SU, Hayes MJ, Rhodes CG, Ind PW, Jones T, Hughes JM. Effect of long-term beta2-agonist dosing on human cardiac beta-adrenoceptor expression in vivo: comparison with changes in lung and mononuclear leukocyte beta-receptors. J Nucl Cardiol 1997; 4:532-8. [PMID: 9456194 DOI: 10.1016/s1071-3581(97)90012-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Tachyphylaxis to the cardiac effects of beta-adrenoceptor stimulation after long-term beta2-agonist administration is well recognized, but the influence on global cardiac beta-adrenoceptor density has not been previously investigated in vivo. Positron emission tomography (PET) has made possible the noninvasive quantification of regional receptor density. This study assesses the effect of long-term beta2-agonist dosing on cardiac beta-adrenoceptors. METHODS AND RESULTS Beta-adrenoceptors in the hearts of 29 healthy male subjects aged 35 +/- 8 years were imaged and quantified in vivo by means of PET and compared with the receptor density in the same subjects' lung tissue. Mononuclear leukocyte (MNL) beta-receptor density was determined in vitro by means of a radioligand binding assay. Beta-receptor density was 8.41 +/- 2.03 pmol/gm tissue in heart, 10.81 +/- 1.91 pmol/gm tissue in lung, and 38.0 +/- 17.5 fmol/mg protein on MNLs. There was a weak relationship between cardiac and pulmonary beta-receptor densities (r = 0.45, p < 0.02) but not between cardiac and MNL receptor density. In seven subjects, the measurements were repeated after 2 weeks of albuterol treatment (4 mg orally twice daily and 200 microg inhaled four times daily in the first week, with doubling of the dose during the second week). After the albuterol treatment, beta-receptor density fell on average by 19% (p < 0.05) in the heart compared with 22% (p < 0.05) in the lung and 42% (p < 0.05) in MNLs. Correlations were found between the percentage changes in receptor density in heart and lung (r = 0.98, p < 0.001) and in heart and MNLs (r = 0.99, p < 0.002). CONCLUSIONS Two weeks of high-dose albuterol results in equivalent downregulation of beta-receptors in vivo, both in the lung and in the heart.
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Affiliation(s)
- F Qing
- Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, UK
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44
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45
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Rosen SD, Boyd H, Rhodes CG, Kaski JC, Camici PG. Myocardial beta-adrenoceptor density and plasma catecholamines in syndrome X. Am J Cardiol 1996; 78:37-42. [PMID: 8712115 DOI: 10.1016/s0002-9149(96)00223-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Recent research has cast doubt on the ischemic hypothesis of etiology of syndrome X (anginal pain, ischemic-like changes in the stress electrocardiogram, but normal coronary arteriogram). Abnormalities of pain perception have been shown and abnormal sympathetic nervous system activation has also been implicated. The aim of this study was to test the hypothesis that downregulation of myocardial beta adrenoceptors is demonstrable in patients with syndrome X. Such downregulation would be consistent with raised myocardial catecholamine concentrations. We performed positron emission tomography with (11)C-CGP-12177 to measure beta-adrenoceptor density. Plasma catecholamines were sampled simultaneously and assayed using high-performance liquid chromatography. Twenty syndrome X patients (11 female, age 57 +/- 9 SD years, range 33 to 69) and 18 matched controls (9 women, age 50 +/- 13 years, range 25 to 65; p = NS vs patients) were studied. Myocardial beta-adrenoceptor density did not differ between syndrome X patients and controls: 8.0 (1.9) pmol/g for patients versus 8.3 (2.1) pmol/g for controls; p = 0.62. No differences were found between patients and controls for plasma norepinephrine (2.82 [1.07] and 2.76 [1.18] nM, respectively; p = 0.89) or for epinephrine (0.29 [0.14] and 0.30 [0.20] nM, respectively; p = 0.84). In patients with syndrome X, beta-adrenoceptor density is normal and, by inference, myocardial catecholamines would also be normal. This weakens the case for a generalized enhancement of sympathetic activation in this disorder, although increased sympathetic reactivity during actual episodes of chest pain remains a possibility.
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Affiliation(s)
- S D Rosen
- MRC Clinical Sciences Centre, Hammersmith Hospital, London, United Kingdom
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46
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Elsinga PH, Vos MG, van Waarde A, Braker AH, de Groot TJ, Anthonio RL, Weemaes AA, Brodde OE, Visser GM, Vaalburg W. (S,S)- and (S,R)-1'-[18F]fluorocarazolol, ligands for the visualization of pulmonary beta-adrenergic receptors with PET. Nucl Med Biol 1996; 23:159-67. [PMID: 8868289 DOI: 10.1016/0969-8051(95)02049-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The beta-adrenoceptor antagonist carazolol has been labelled with fluorine-18 in the isopropyl group via a reductive alkylation by [18F]-fluoroacetone of the corresponding (S)-desisopropyl compound according to a known procedure. The introduction of fluorine in the isopropyl group creates a new stereogenic centre resulting in the formation of (S,S)- and (S,R)-1'-[18F]fluorocarazolol, which were separated by HPLC. Tissue distribution studies were performed in male Wistar rats. Both the (S,S)- and (S,R)-diastereomers (S.A. 500-2000 Ci/mmol; 18.5-74 TBq/mmol) showed high uptake in lung and heart, which could be blocked by pretreatment of the animals with (+/-)-propranolol. No significant differences were observed between the biodistribution of the two diastereomers. Metabolite analysis showed a rapid appearance of polar metabolites in plasma, while at 60 min postinjection 92% and 82% of the total radioactivity in lung and heart was unmetabolized 1'-[18F]fluorocarazolol. In a PET-study with male Wistar rats, the lungs were clearly visualized and the pulmonary uptake was decreased after pretreatment of the animals with (+/-)-propranolol. The heart could not be visualized. Similar results were obtained in PET-studies with lambs.
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Affiliation(s)
- P H Elsinga
- Pet-Center, University Hospital, Groningen, Netherlands
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47
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Choudhury L, Guzzetti S, Lefroy DC, Nihoyannopoulos P, McKenna WJ, Oakley CM, Camici PG. Myocardial beta adrenoceptors and left ventricular function in hypertrophic cardiomyopathy. HEART (BRITISH CARDIAC SOCIETY) 1996; 75:50-4. [PMID: 8624872 PMCID: PMC484222 DOI: 10.1136/hrt.75.1.50] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To assess the relation between left ventricular function and myocardial beta adrenoceptor density. METHODS 17 patients with hypertrophic cardiomyopathy, six with and 11 without heart failure, were studied. Left ventricular function was assessed by echocardiography, and myocardial beta adrenoceptors by positron emission tomography. Patient data were compared with those obtained in normal controls. RESULTS Myocardial beta adrenoceptor density in the 17 patients was 7.00 (SD 1.90) pmol/g v 11.50 (2.18) pmol/g in normal controls (P < 0.01). beta Adrenoceptor density in the six patients with left ventricular failure was 5.61 (0.88) pmol/g v 7.71 (1.86) pmol/g in the 11 patients with normal ventricular function (P < 0.05), and there was a significant correlation (r = 0.52; P < 0.05) between left ventricular fractional shortening and myocardial beta adrenoceptor density. A positive correlation (r = 0.51; P < 0.05) was also found between myocardial beta adrenoceptor density and the E/A transmitral flow ratio, an index of left ventricular diastolic function. CONCLUSIONS There is myocardial beta adrenoceptor downregulation in patients with hypertrophic cardiomyopathy with or without signs of heart failure.
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Affiliation(s)
- L Choudhury
- MRC Clinical Sciences Centre, Hammersmith Hospital, London
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Radvan J, Marwick TH, Williams MJ, Camici PG. Evaluation of the extent and timing of the coronary hyperemic response to dipyridamole: a study with transesophageal echocardiography and positron emission tomography with oxygen 15 water. J Am Soc Echocardiogr 1995; 8:864-73. [PMID: 8611286 DOI: 10.1016/s0894-7317(05)80010-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Coronary flow reserve may be measured with Doppler-derived coronary blood-flow velocity or scintigraphic assessment of myocardial perfusion. The purpose of this study was to compare coronary flow velocity and perfusion measures of flow reserve with respect to their extent and time course. Coronary flow velocity reserve in the proximal left anterior descending coronary artery measured by pulsed-wave Doppler at transesophageal echocardiography, with measures of perfusion reserve obtained in the corresponding territory, were measured by a standard O15 water technique at positron emission tomography. Eighteen male volunteers underwent both tests on different days in random order, with dipyridamole stress (0.56 mg/kg). After correction of resting flow and perfusion measurements to a standard cardiac workload (to compensate for heterogeneity in hemodynamics between the two studies), coronary flow reserve was calculated as the ratio between dipyridamoleand corrected resting flow. The uncorrected perfusion reserve measured by positron emission tomography was 3.7 +/- 1.2, compared with a corrected perfusion reserve of 2.3 +/- 0.7. This correlated with a corrected flow velocity reserve of 2.9 +/- 1.0 at transesophageal echocardiography (R = 0.92; p < 0.001). The mean difference between these results was 0.58 +/- 0.41; discrepant results occurred at higher flows, in the presence of discordant blood pressure responses to stress, and because of intersubject variations in the timing of the peak coronary flow response, which were detected by continuous monitoring at transesophageal echocardiography. Measurement of coronary flow reserve at transesophageal echocardiography correlates well with measurements at positron emission tomography, and discrepancies are minimized if measurements are taken at the same time after dipyridamole.
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Affiliation(s)
- J Radvan
- Department of Academic Cardiology, St. Mary's Hospital Medical School, London, United Kingdom
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Voipio-Pulkki LM. Relevance of PET/SPET tracers for cardiac neurotransmission. Nucl Med Biol 1995; 22:1027-35. [PMID: 8998462 DOI: 10.1016/0969-8051(95)02026-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- L M Voipio-Pulkki
- Department of Medicine and Cyclotron-PET Center, University of Turku, Finland
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50
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Fei L, Slade AK, Prasad K, Malik M, McKenna WJ, Camm AJ. Is there increased sympathetic activity in patients with hypertrophic cardiomyopathy? J Am Coll Cardiol 1995; 26:472-80. [PMID: 7608453 DOI: 10.1016/0735-1097(95)80025-c] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVES This study aimed to assess autonomic nervous system activity in patients with hypertrophic cardiomyopathy. BACKGROUND Patients with hypertrophic cardiomyopathy are traditionally thought to have increased sympathetic activity. However, convincing evidence is lacking. METHODS Heart rate variability was assessed from 24-h ambulatory electrocardiographic (Holter) recordings in 31 patients with hypertrophic cardiomyopathy and 31 age- and gender-matched normal control subjects in a drug-free state. Spectral heart rate variability was calculated as total (0.01 to 1.00 Hz), low (0.04 to 0.15 Hz) and high (0.15 to 0.40 Hz) frequency components using fast Fourier transformation analysis. RESULTS There was a nonsignificant decrease in the total frequency component of heart rate variability in patients with hypertrophic cardiomyopathy compared with that of normal subjects (mean +/- SD 7.24 +/- 0.88 versus 7.59 +/- 0.57 ln[ms2], p = 0.072). Although there was no significant difference in the high frequency component (5.31 +/- 1.14 versus 5.40 +/- 0.91 ln[ms2], p = 0.730), the low frequency component was significantly lower in patients than in normal subjects (6.25 +/- 1.00 versus 6.72 +/- 0.61 ln[ms2], p = 0.026). After normalization (i.e., division by the total frequency component values), the low frequency component was significantly decreased (38 +/- 8% versus 43 +/- 8%, p = 0.018) and the high frequency component significantly increased (16 +/- 6% versus 12 +/- 6%, p = 0.030) in patients with hypertrophic cardiomyopathy. The low/high frequency component ratio was significantly lower in these patients (0.94 +/- 0.64 versus 1.33 +/- 0.55, p = 0.013). In patients with hypertrophic cardiomyopathy, heart rate variability was significantly related to left ventricular end-systolic dimension and left atrial dimension but not to maximal left ventricular wall thickness. No significant difference in heart rate variability was found between 14 victims of sudden cardiac death and 10 age- and gender-matched low risk patients. CONCLUSIONS Our observations suggest that during normal daily activities, patients with hypertrophic cardiomyopathy experience a significant autonomic alteration with decreased sympathetic tone.
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Affiliation(s)
- L Fei
- Department of Cardiological Sciences, St. George's Hospital Medical School, London, England, United Kingdom
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