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Mueller-Graf F, Frenkel P, Merz J, Reuter S, Vollmar B, Tusman G, Pulletz S, Böhm SH, Zitzmann A, Reuter DA, Adler A. Respiratory gating improves correlation between pulse wave transit time and pulmonary artery pressure in experimental pulmonary hypertension. Physiol Meas 2024; 45:03NT02. [PMID: 38422512 DOI: 10.1088/1361-6579/ad2eb5] [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: 07/17/2023] [Accepted: 02/29/2024] [Indexed: 03/02/2024]
Abstract
Objective. Since pulse wave transit time (PWTT) shortens as pulmonary artery pressure (PAP) increases it was suggested as a potential non-invasive surrogate for PAP. The state of tidal lung filling is also known to affect PWTT independently of PAP. The aim of this retrospective analysis was to test whether respiratory gating improved the correlation coefficient between PWTT and PAP.Approach. In each one of five anesthetized and mechanically ventilated pigs two high-fidelity pressure catheters were placed, one directly behind the pulmonary valve, and the second one in a distal branch of the pulmonary artery. PAP was raised using the thromboxane A2 analogue U46619 and animals were ventilated in a pressure controlled mode (I:E ratio 1:2, respiratory rate 12/min, tidal volume of 6 ml kg-1). All signals were recorded using the multi-channel platform PowerLab®. The arrival of the pulse wave at each catheter tip was determined using a MATLAB-based modified hyperbolic tangent algorithm and PWTT calculated as the time interval between these arrivals.Main results. Correlation coefficient for PWTT and mean PAP wasr= 0.932 for thromboxane. This correlation coefficient increased considerably when heart beats either at end-inspiration (r= 0.978) or at end-expiration (r= 0.985) were selected (=respiratory gating).Significance. The estimation of mean PAP from PWTT improved significantly when taking the respiratory cycle into account. Respiratory gating is suggested to improve for the estimation of PAP by PWTT.
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Affiliation(s)
- Fabian Mueller-Graf
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Medical Center Rostock, Schillingallee 35, D-18057 Rostock, Germany
- Rudolf-Zenker-Institute for Experimental Surgery, University Medical Center Rostock, D-18057 Rostock, Germany
| | - Paul Frenkel
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Medical Center Rostock, Schillingallee 35, D-18057 Rostock, Germany
| | - Jonas Merz
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Medical Center Rostock, Schillingallee 35, D-18057 Rostock, Germany
| | - Susanne Reuter
- Rudolf-Zenker-Institute for Experimental Surgery, University Medical Center Rostock, D-18057 Rostock, Germany
| | - Brigitte Vollmar
- Rudolf-Zenker-Institute for Experimental Surgery, University Medical Center Rostock, D-18057 Rostock, Germany
| | - Gerardo Tusman
- Department of Anesthesiology, Hospital Privado de Comunidad, Mar del Plata, Buenos Aires, Argentina
| | - Sven Pulletz
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Medical Center Rostock, Schillingallee 35, D-18057 Rostock, Germany
| | - Stephan H Böhm
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Medical Center Rostock, Schillingallee 35, D-18057 Rostock, Germany
| | - Amelie Zitzmann
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Medical Center Rostock, Schillingallee 35, D-18057 Rostock, Germany
| | - Daniel A Reuter
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Medical Center Rostock, Schillingallee 35, D-18057 Rostock, Germany
| | - Andy Adler
- Systems and Computer Engineering, Carleton University, Ottawa, Canada
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Wernz MM, Voskrebenzev A, Müller RA, Zubke M, Klimeš F, Glandorf J, Czerner C, Wacker F, Olsson KM, Hoeper MM, Hohlfeld JM, Vogel-Claussen J. Feasibility, Repeatability, and Correlation to Lung Function of Phase-Resolved Functional Lung (PREFUL) MRI-derived Pulmonary Artery Pulse Wave Velocity Measurements. J Magn Reson Imaging 2024. [PMID: 38460124 DOI: 10.1002/jmri.29337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 02/22/2024] [Accepted: 02/22/2024] [Indexed: 03/11/2024] Open
Abstract
BACKGROUND Pulse wave velocity (PWV) in the pulmonary arteries (PA) is a marker of vascular stiffening. Currently, only phase-contrast (PC) MRI-based options exist to measure PA-PWV. PURPOSE To test feasibility, repeatability, and correlation to clinical data of Phase-Resolved Functional Lung (PREFUL) MRI-based calculation of PA-PWV. STUDY TYPE Retrospective. SUBJECTS 79 (26 female) healthy subjects (age range 19-78), 58 (24 female) patients with chronic obstructive pulmonary disease (COPD, age range 40-77), 60 (33 female) patients with suspected pulmonary hypertension (PH, age range 28-85). SEQUENCE 2D spoiled gradient echo, 1.5T. ASSESSMENT PA-PWV was measured from PREFUL-derived cardiac cycles based on the determination of temporal and spatial distance between lung vasculature voxels using a simplified (sPWV) method and a more comprehensive (cPWV) method including more elaborate distance calculation. For 135 individuals, PC MRI-based PWV (PWV-QA) was measured. STATISTICAL TESTS Intraclass-correlation-coefficient (ICC) and coefficient of variation (CoV) were used to test repeatability. Nonparametric tests were used to compare cohorts. Correlation of sPWV/cPWV, PWV-QA, forced expiratory volume in 1 sec (FEV1 ) %predicted, residual volume (RV) %predicted, age, and right heart catheterization (RHC) data were tested. Significance level α = 0.05 was used. RESULTS sPWV and cPWV showed no significant differences between repeated measurements (P-range 0.10-0.92). CoV was generally lower than 15%. COPD and PH patients had significantly higher sPWV and cPWV than healthy subjects. Significant correlation was found between sPWV or cPWV and FEV1 %pred. (R = -0.36 and R = -0.44), but not with RHC (P-range -0.11 - 0.91) or age (P-range 0.23-0.89). Correlation to RV%pred. was significant for cPWV (R = 0.42) but not for sPWV (R = 0.34, P = 0.055). For all cohorts, sPWV and cPWV were significantly correlated with PWV-QA (R = -0.41 and R = 0.48). DATA CONCLUSION PREFUL-derived PWV is feasible and repeatable. PWV is increased in COPD and PH patients and correlates to airway obstruction and hyperinflation. LEVEL OF EVIDENCE 3 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Marius M Wernz
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
| | - Andreas Voskrebenzev
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
| | - Robin A Müller
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
| | - Maximilian Zubke
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
| | - Filip Klimeš
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
| | - Julian Glandorf
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
| | - Christoph Czerner
- Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany
| | - Frank Wacker
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
| | - Karen M Olsson
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
- Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, Hannover, Germany
| | - Marius M Hoeper
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
- Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, Hannover, Germany
| | - Jens M Hohlfeld
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
- Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, Hannover, Germany
- Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover, Germany
| | - Jens Vogel-Claussen
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany
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3
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Gupta A, Sharifov OF, Lloyd SG, Tallaj JA, Aban I, Dell'italia LJ, Denney TS, Gupta H. Novel Noninvasive Assessment of Pulmonary Arterial Stiffness Using Velocity Transfer Function. J Am Heart Assoc 2019; 7:e009459. [PMID: 30371198 PMCID: PMC6222968 DOI: 10.1161/jaha.118.009459] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Background Pulmonary artery (PA) stiffness is associated with increased pulmonary vascular resistance (PVR). PA stiffness is accurately described by invasive PA impedance because it considers pulsatile blood flow through elastic PAs. We hypothesized that PA stiffness and impedance could be evaluated noninvasively by PA velocity transfer function (VTF), calculated as a ratio of the frequency spectra of output/input mean velocity profiles in PAs. Methods and Results In 20 participants (55±19 years, 14 women) undergoing clinically indicated right‐sided heart catheterization, comprehensive phase‐contrast and cine‐cardiac magnetic resonance imaging was performed to calculate PA VTF, along with right ventricular mass and function. PA impedance was measured as a ratio of frequency spectra of invasive PA pressure and echocardiographically derived PA flow waveforms. Mean PA pressure was 29.5±13.6 mm Hg, and PVR was 3.5±2.8 Wood units. A mixed‐effects model showed VTF was significantly associated with PA impedance independent of elevation in pulmonary capillary wedge pressure (P=0.005). The mean of higher frequency moduli of VTF correlated with PVR (ρ=0.63; P=0.003) and discriminated subjects with low (n=10) versus elevated PVR (≥2.5 Wood units, n=10), with an area under the curve of 0.95, similar to discrimination by impedance (area under the curve=0.93). VTF had a strong inverse association with right ventricular ejection fraction (ρ=−0.73; P<0.001) and a significant positive correlation with right ventricular mass index (ρ=0.51; P=0.02). Conclusions VTF, a novel right ventricular–PA axis coupling parameter, is a surrogate for PA impedance with the potential to assess PA stiffness and elevation in PVR noninvasively and reliably using cardiac magnetic resonance imaging.
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Affiliation(s)
- Ankur Gupta
- 1 Division of Cardiovascular Disease Department of Medicine University of Alabama at Birmingham AL.,3 Division of Cardiovascular Medicine and Department of Radiology Brigham and Women's Hospital Heart and Vascular Center Harvard Medical School Boston MA
| | - Oleg F Sharifov
- 1 Division of Cardiovascular Disease Department of Medicine University of Alabama at Birmingham AL
| | - Steven G Lloyd
- 1 Division of Cardiovascular Disease Department of Medicine University of Alabama at Birmingham AL.,4 Veterans Affairs Medical Center Birmingham AL
| | - Jose A Tallaj
- 1 Division of Cardiovascular Disease Department of Medicine University of Alabama at Birmingham AL.,4 Veterans Affairs Medical Center Birmingham AL
| | - Inmaculada Aban
- 2 Department of Biostatistics University of Alabama at Birmingham AL
| | - Louis J Dell'italia
- 1 Division of Cardiovascular Disease Department of Medicine University of Alabama at Birmingham AL.,4 Veterans Affairs Medical Center Birmingham AL
| | - Thomas S Denney
- 5 Department of Electrical and Computer Engineering Auburn University Auburn AL
| | - Himanshu Gupta
- 1 Division of Cardiovascular Disease Department of Medicine University of Alabama at Birmingham AL.,4 Veterans Affairs Medical Center Birmingham AL.,6 Valley Medical Group Ridgewood NJ
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4
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Jankowich M, Abbasi SA, Vang A, Choudhary G. Right Ventricular Fibrosis Is Related to Pulmonary Artery Stiffness in Pulmonary Hypertension: A Cardiac Magnetic Resonance Imaging Study. Am J Respir Crit Care Med 2019; 200:776-779. [PMID: 31144985 PMCID: PMC6775868 DOI: 10.1164/rccm.201903-0580le] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Affiliation(s)
- Matthew Jankowich
- Providence VA Medical CenterProvidence, Rhode Islandand
- Alpert Medical School of Brown UniversityProvidence, Rhode Island
| | - Siddique A. Abbasi
- Providence VA Medical CenterProvidence, Rhode Islandand
- Alpert Medical School of Brown UniversityProvidence, Rhode Island
| | - Alexander Vang
- Providence VA Medical CenterProvidence, Rhode Islandand
- Alpert Medical School of Brown UniversityProvidence, Rhode Island
| | - Gaurav Choudhary
- Providence VA Medical CenterProvidence, Rhode Islandand
- Alpert Medical School of Brown UniversityProvidence, Rhode Island
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5
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Forouzan O, Dinges E, Runo JR, Keevil JG, Eickhoff JC, Francois C, Chesler NC. Exercise-Induced Changes in Pulmonary Artery Stiffness in Pulmonary Hypertension. Front Physiol 2019; 10:269. [PMID: 31001123 PMCID: PMC6454859 DOI: 10.3389/fphys.2019.00269] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 02/28/2019] [Indexed: 11/23/2022] Open
Abstract
Background: Pulmonary hypertension causes pulmonary artery (PA) stiffening, which overloads the right ventricle (RV). Since symptoms of pulmonary hypertension (PH) are exacerbated by exercise, exercise-induced PA stiffening is relevant to cardiopulmonary status. Here, we sought to demonstrate the feasibility of using magnetic resonance imaging (MRI) for non-invasive assessment of exercise-induced changes in PA stiffness in patients with PH. Methods: MRI was performed on 7 PH patients and 8 age-matched control subjects at rest and during exercise stress. Main pulmonary artery (MPA) relative area change (RAC) and pulse wave velocity (PWV) were measured from 2D-PC images. Invasive right heart catheterization (RHC) was performed on 5 of the PH patients in conjunction with exercise stress to measure MPA pressures and stiffness index (β). Results: Heart rate and cardiac index (CI) were significantly increased with exercise in both groups. In controls, RAC decreased from 0.27 ± 0.05 at rest to 0.22 ± 0.06 with exercise (P < 0.05); a modest increase in PWV was not significant (P = 0.06). In PH patients, RAC decreased from 0.15 ± 0.02 to 0.11 ± 0.01 (P < 0.05) and PWV and β increased from 3.9 ± 0.54 m/s and 1.86 ± 0.12 at rest to 5.75 ± 0.70 m/s and 3.25 ± 0.26 with exercise (P < 0.05 for both), respectively. These results confirm increased MPA stiffness with exercise stress in both groups and the non-invasive metrics of MPA stiffness correlated well with β. Finally, as assessed by PWV but not RAC, PA stiffness of PH patients increased more than that of controls for comparable levels of moderate exercise. Conclusion: These results demonstrate the feasibility of using MRI for non-invasive assessment of exercise-induced changes in MPA stiffness in a small, heterogeneous group of PH patients in a research context. Similar measurements in a larger cohort are required to investigate differences between PWV and RAC for estimation of MPA stiffness.
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Affiliation(s)
- Omid Forouzan
- College of Engineering, University of Wisconsin-Madison, Madison, WI, United States
| | - Eric Dinges
- College of Engineering, University of Wisconsin-Madison, Madison, WI, United States
| | - James R Runo
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
| | - Jonathan G Keevil
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
| | - Jens C Eickhoff
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
| | - Christopher Francois
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
| | - Naomi C Chesler
- College of Engineering, University of Wisconsin-Madison, Madison, WI, United States.,School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
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Weir-McCall JR, Liu-Shiu-Cheong PS, Struthers AD, Lipworth BJ, Houston JG. Pulmonary arterial stiffening in COPD and its implications for right ventricular remodelling. Eur Radiol 2018; 28:3464-3472. [PMID: 29488084 PMCID: PMC6028842 DOI: 10.1007/s00330-018-5346-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 01/16/2018] [Accepted: 01/18/2018] [Indexed: 01/09/2023]
Abstract
Background Pulmonary pulse wave velocity (PWV) allows the non-invasive measurement of pulmonary arterial stiffening, but has not previously been assessed in COPD. The aim of the current study was to assess PWV in COPD and its association with right ventricular (RV) remodelling. Methods Fifty-eight participants with COPD underwent pulmonary function tests, 6-min walk test and cardiac MRI, while 21 healthy controls (HCs) underwent cardiac MRI. Thirty-two COPD patients underwent a follow-up MRI to assess for longitudinal changes in RV metrics. Cardiac MRI was used to quantify RV mass, volumes and PWV. Differences in continuous variables between the COPD and HC groups was tested using an independent t-test, and associations between PWV and right ventricular parameters was examined using Pearson’s correlation coefficient. Results Those with COPD had reduced pulsatility (COPD (mean±SD):24.88±8.84% vs. HC:30.55±11.28%, p=0.021), pulmonary acceleration time (COPD:104.0±22.9ms vs. HC: 128.1±32.2ms, p<0.001), higher PWV (COPD:2.62±1.29ms-1 vs. HC:1.78±0.72ms-1, p=0.001), lower RV end diastolic volume (COPD:53.6±11.1ml vs. HC:59.9±13.0ml, p=0.037) and RV stroke volume (COPD:31.9±6.9ml/m2 vs. HC:37.1±6.2ml/m2, p=0.003) with no difference in mass (p=0.53). PWV was not associated with right ventricular parameters. Conclusions While pulmonary vascular remodelling is present in COPD, cardiac remodelling favours reduced filling rather than increased afterload. Treatment of obstructive lung disease may have greater effect on cardiac function than treatment of pulmonary vascular disease in most COPD patients Key Points • Pulmonary pulse wave velocity (PWV) is elevated in COPD. • Pulmonary PWV is not associated with right ventricular remodelling. • Right ventricular remodelling is more in keeping with that of reduced filling. Electronic supplementary material The online version of this article (10.1007/s00330-018-5346-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jonathan R Weir-McCall
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, UK
| | - Patrick Sk Liu-Shiu-Cheong
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, UK
| | - Allan D Struthers
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, UK
| | - Brian J Lipworth
- Scottish Centre for Respiratory Research, Medical Research Institute, University of Dundee, Dundee, UK
| | - J Graeme Houston
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, UK.
- Division of Cardiovascular and Diabetes Medicine, Ninewells Hospital, Dundee, DD1 9SY, UK.
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Weir-McCall JR, Kamalasanan A, Cassidy DB, Struthers AD, Lipworth BJ, Houston JG. Assessment of proximal pulmonary arterial stiffness using magnetic resonance imaging: effects of technique, age and exercise. BMJ Open Respir Res 2016; 3:e000149. [PMID: 27843548 PMCID: PMC5073626 DOI: 10.1136/bmjresp-2016-000149] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Revised: 09/16/2016] [Accepted: 09/19/2016] [Indexed: 01/09/2023] Open
Abstract
Introduction To compare the reproducibility of pulmonary pulse wave velocity (PWV) techniques, and the effects of age and exercise on these. Methods 10 young healthy volunteers (YHV) and 20 older healthy volunteers (OHV) with no cardiac or lung condition were recruited. High temporal resolution phase contrast sequences were performed through the main pulmonary arteries (MPAs), right pulmonary arteries (RPAs) and left pulmonary arteries (LPAs), while high spatial resolution sequences were obtained through the MPA. YHV underwent 2 MRIs 6 months apart with the sequences repeated during exercise. OHV underwent an MRI scan with on-table repetition. PWV was calculated using the transit time (TT) and flow area techniques (QA). 3 methods for calculating QA PWV were compared. Results PWV did not differ between the two age groups (YHV 2.4±0.3/ms, OHV 2.9±0.2/ms, p=0.1). Using a high temporal resolution sequence through the RPA using the QA accounting for wave reflections yielded consistently better within-scan, interscan, intraobserver and interobserver reproducibility. Exercise did not result in a change in either TT PWV (mean (95% CI) of the differences: −0.42 (−1.2 to 0.4), p=0.24) or QA PWV (mean (95% CI) of the differences: 0.10 (−0.5 to 0.9), p=0.49) despite a significant rise in heart rate (65±2 to 87±3, p<0.0001), blood pressure (113/68 to 130/84, p<0.0001) and cardiac output (5.4±0.4 to 6.7±0.6 L/min, p=0.004). Conclusions QA PWV performed through the RPA using a high temporal resolution sequence accounting for wave reflections yields the most reproducible measurements of pulmonary PWV.
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Affiliation(s)
- Jonathan R Weir-McCall
- Division of Cardiovascular and Diabetes Medicine , Medical Research Institute, University of Dundee , Dundee , UK
| | - Anu Kamalasanan
- Department of Clinical Radiology , Ninewells Hospital and Medical School , Dundee , UK
| | - Deidre B Cassidy
- Division of Cardiovascular and Diabetes Medicine , Medical Research Institute, University of Dundee , Dundee , UK
| | - Allan D Struthers
- Division of Cardiovascular and Diabetes Medicine , Medical Research Institute, University of Dundee , Dundee , UK
| | - Brian J Lipworth
- Scottish Centre for Respiratory Research, Medical Research Institute, University of Dundee , Dundee , UK
| | - J Graeme Houston
- Division of Cardiovascular and Diabetes Medicine , Medical Research Institute, University of Dundee , Dundee , UK
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Abstract
Pulmonary hypertension (PH) is a life-threatening, multifactorial pathophysiological haemodynamic condition, diagnosed when the mean pulmonary arterial pressure equals or exceeds 25 mmHg at rest during right heart catheterization. Cardiac MRI, in general, and MR phase-contrast (PC) imaging, in particular, have emerged as potential techniques for the standardized assessment of cardiovascular function, morphology and haemodynamics in PH. Allowing the quantification and characterization of macroscopic cardiovascular blood flow, MR PC imaging offers non-invasive evaluation of haemodynamic alterations associated with PH. Techniques used to study the PH include both the routine two-dimensional (2D) approach measuring predominant velocities through an acquisition plane and the rapidly evolving four-dimensional (4D) PC imaging, which enables the assessment of the complete time-resolved, three-directional blood-flow velocity field in a volume. Numerous parameters such as pulmonary arterial mean velocity, vessel distensibility, flow acceleration time and volume and tricuspid regurgitation peak velocity, as well as the duration and onset of vortical blood flow in the main pulmonary artery, have been explored to either diagnose PH or find non-invasive correlates to right heart catheter parameters. Furthermore, PC imaging-based analysis of pulmonary arterial pulse-wave velocities, wall shear stress and kinetic energy losses grants novel insights into cardiopulmonary remodelling in PH. This review aimed to outline the current applications of 2D and 4D PC imaging in PH and show why this technique has the potential to contribute significantly to early diagnosis and characterization of PH.
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Affiliation(s)
- Ursula Reiter
- 1 Division of General Radiology, Department of Radiology, Medical University of Graz, Austria
| | - Gert Reiter
- 2 Research and Development, Siemens Healthcare, Graz, Austria
| | - Michael Fuchsjäger
- 1 Division of General Radiology, Department of Radiology, Medical University of Graz, Austria
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9
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Dawes TJW, Gandhi A, de Marvao A, Buzaco R, Tokarczuk P, Quinlan M, Durighel G, Diamond T, Monje Garcia L, de Cesare A, Cook SA, O'Regan DP. Pulmonary Artery Stiffness Is Independently Associated with Right Ventricular Mass and Function: A Cardiac MR Imaging Study. Radiology 2016; 280:398-404. [PMID: 26909648 DOI: 10.1148/radiol.2016151527] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Purpose To determine the relationship between pulmonary artery (PA) stiffness and both right ventricular (RV) mass and function with cardiac magnetic resonance (MR) imaging. Materials and Methods The study was approved by the local research ethics committee, and all participants gave written informed consent. Cardiac MR imaging was performed at 1.5 T in 156 healthy volunteers (63% women; age range, 19-61 years; mean age, 36.1 years). High-temporal-resolution phase-contrast imaging was performed in the main and right PAs. Pulmonary pulse wave velocity (PWV) was determined by the interval between arterial systolic upslopes. RV function was assessed with feature tracking to derive peak systolic strain and strain rate, as well as peak early-diastolic strain rate. RV volumes, ejection fraction (RVEF), and mass were measured from the cine images. The association of pulmonary PWV with RV function and mass was quantified with univariate linear regression. Interstudy repeatability was assessed with intraclass correlation. Results The repeatability coefficient for pulmonary PWV was 0.96. Increases in pulmonary PWV and RVEF were associated with increases in age (r = 0.32, P < .001 and r = 0.18, P = .025, respectively). After adjusting for age (P = .090), body surface area (P = .073), and sex (P = .005), pulmonary PWV demonstrated an independent positive association with RVEF (r = 0.34, P = .026). Significant associations were also seen with RV mass (r = 0.41, P = .004), RV radial strain (r = 0.38, P = .022), and strain rate (r = 0.35, P = .002), and independent negative associations were seen with radial (r = 0.27, P = .003), longitudinal (r = 0.40, P = .007), and circumferential (r = 0.31, P = .005) peak early-diastolic strain rate with the same covariates. Conclusion Pulmonary PWV is reliably assessed with cardiac MR imaging. In subjects with no known cardiovascular disease, increasing PA stiffness is associated with increasing age and is also moderately associated with both RV mass and function after controlling for age, body surface area, and sex. (©) RSNA, 2016 Online supplemental material is available for this article.
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Affiliation(s)
- Timothy J W Dawes
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Ajay Gandhi
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Antonio de Marvao
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Rui Buzaco
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Paweł Tokarczuk
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Marina Quinlan
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Giuliana Durighel
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Tamara Diamond
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Laura Monje Garcia
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Alain de Cesare
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Stuart A Cook
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
| | - Declan P O'Regan
- From the Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, England (T.J.W.D., A.d.M., R.B., P.T., M.Q., G.D., T.D., L.M.G., S.A.C., D.P.O'R.); Department of Cardiology, Imperial College NHS Healthcare Trust, London, England (A.G.); and Sorbonne Universités, UPMC Univ Paris 06, INSERM UMR_S 1146, CNRS UMR 7371, Lib, Paris, France (A.d.C.)
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10
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Forouzan O, Warczytowa J, Wieben O, François CJ, Chesler NC. Non-invasive measurement using cardiovascular magnetic resonance of changes in pulmonary artery stiffness with exercise. J Cardiovasc Magn Reson 2015; 17:109. [PMID: 26653289 PMCID: PMC4677443 DOI: 10.1186/s12968-015-0213-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 11/24/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Exercise stress tests are commonly used in clinical settings to monitor the functional state of the heart and vasculature. Large artery stiffness is one measure of arterial function that can be quantified noninvasively during exercise stress. Changes in proximal pulmonary artery stiffness are especially relevant to the progression of pulmonary hypertension (PH), since pulmonary artery (PA) stiffness is the best current predictor of mortality from right ventricular failure. METHODS Cardiovascular magnetic resonance (CMR) was used to investigate the effect of exercise stress on PA pulse wave velocity (PWV) and relative area change (RAC), which are both non-invasive measures of PA stiffness, in healthy subjects. All 21 subjects (average age 26 ± 4 years; 13 female and 8 male) used a custom-made MR-compatible stepping device to exercise (two stages of mild-to-moderate exercise of 3-4 min duration each) in a supine position within the confines of the scanner. To measure the cross-sectional area and blood flow velocity in the main PA (MPA), two-dimensional phase-contrast (2D-PC) CMR images were acquired. To measure the reproducibility of metrics, CMR images were analyzed by two independent observers. Inter-observer agreements were calculated using the intraclass correlation and Bland-Altman analysis. RESULTS From rest to the highest level of exercise, cardiac output increased from 5.9 ± 1.4 L/min to 8.2 ± 1.9 L/min (p < 0.05), MPA PWV increased from 1.6 ± 0.5 m/s to 3.6 ± 1.4 m/s (p < 0.05), and MPA RAC decreased from 0.34 ± 0.11 to 0.24 ± 0.1 (p < 0.05). While PWV also increased from the first to second exercise stage (from 2.7 ± 1.0 m/s to 3.6 ± 1.4 m/s, p < 0.05), there was no significant change in RAC between the two exercise stages. We found good inter-observer agreement for quantification of MPA flow, RAC and PWV. CONCLUSION These results demonstrate that metrics of MPA stiffness increase in response to acute moderate exercise in healthy subjects and that CMR exercise stress offers great potential in clinical practice to noninvasively assess vascular function.
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Affiliation(s)
- Omid Forouzan
- Department of Biomedical Engineering, University of Wisconsin-Madison, Engineering Centers Building, 1550 Engineering Drive, Madison, WI, 53706, USA.
| | - Jared Warczytowa
- Department of Biomedical Engineering, University of Wisconsin-Madison, Engineering Centers Building, 1550 Engineering Drive, Madison, WI, 53706, USA.
| | - Oliver Wieben
- Department of Biomedical Engineering, University of Wisconsin-Madison, Engineering Centers Building, 1550 Engineering Drive, Madison, WI, 53706, USA.
- Department of Medical Physics, Wisconsin Institutes for Medical Research, 1111 Highland Avenue, Madison, WI, 53705-2275, USA.
- Department of Radiology, University of Wisconsin, School of Medicine and Public Health, E3/366 Clinical Science Center, 600 Highland Avenue, Madison, WI, 53792-3252, USA.
| | - Christopher J François
- Department of Radiology, University of Wisconsin, School of Medicine and Public Health, E3/366 Clinical Science Center, 600 Highland Avenue, Madison, WI, 53792-3252, USA.
| | - Naomi C Chesler
- Department of Biomedical Engineering, University of Wisconsin-Madison, Engineering Centers Building, 1550 Engineering Drive, Madison, WI, 53706, USA.
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11
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Ibrahim ESH, Bajwa AA, White RD. Assessment of Pulmonary Arterial Hypertension by Magnetic Resonance Imaging. Tomography 2015; 1:23-29. [PMID: 30042953 PMCID: PMC6024412 DOI: 10.18383/j.tom.2015.00118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Pulmonary arterial hypertension (PAH) is characterized by elevated pulmonary artery pressure (PAP), altered pulmonary artery (PA) hemodynamics, and vessel wall characteristics that affect the right ventricular (RV) function. Magnetic resonance imaging (MRI) has recently been considered in PAH and has shown promising results for estimating PAP, measuring PA hemodynamic parameters, assessing PA vessel wall stiffness, and evaluating RV global and regional functions. In this article, we review various MRI techniques and image analysis methods for evaluating PAH, with an emphasis on the resulting images and how they are interpreted for both qualitatively and quantitatively assessing the PA and RV conditions.
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Affiliation(s)
| | - Abubakr A Bajwa
- Department of Medicine, University of Florida, Jacksonville, FL; and
| | - Richard D White
- Department of Radiology, Ohio State University, Columbus, OH
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12
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Weir-McCall JR, Struthers AD, Lipworth BJ, Houston JG. The role of pulmonary arterial stiffness in COPD. Respir Med 2015; 109:1381-90. [PMID: 26095859 PMCID: PMC4646836 DOI: 10.1016/j.rmed.2015.06.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Revised: 05/10/2015] [Accepted: 06/10/2015] [Indexed: 12/23/2022]
Abstract
COPD is the second most common cause of pulmonary hypertension, and is a common complication of severe COPD with significant implications for both quality of life and mortality. However, the use of a rigid diagnostic threshold of a mean pulmonary arterial pressure (mPAP) of ≥25mHg when considering the impact of the pulmonary vasculature on symptoms and disease is misleading. Even minimal exertion causes oxygen desaturation and elevations in mPAP, with right ventricular hypertrophy and dilatation present in patients with mild to moderate COPD with pressures below the threshold for diagnosis of pulmonary hypertension. This has significant implications, with right ventricular dysfunction associated with poorer exercise capability and increased mortality independent of pulmonary function tests. The compliance of the pulmonary artery (PA) is a key component in decoupling the right ventricle from the pulmonary bed, allowing the right ventricle to work at maximum efficiency and protecting the microcirculation from large pressure gradients. PA stiffness increases with the severity of COPD, and correlates well with the presence of exercise induced pulmonary hypertension. A curvilinear relationship exists between PA distensibility and mPAP and pulmonary vascular resistance (PVR) with marked loss of distensibility before a rapid rise in mPAP and PVR occurs with resultant right ventricular failure. This combination of features suggests PA stiffness as a promising biomarker for early detection of pulmonary vascular disease, and to play a role in right ventricular failure in COPD. Early detection would open this up as a potential therapeutic target before end stage arterial remodelling occurs. Pulmonary hypertension is common in COPD. Right ventricular remodeling occurs at pressures below the diagnostic threshold of PH. Pulmonary arterial stiffening occurs early in the development of PH. Non-invasive measurement of pulmonary stiffness may serve as an early biomarker of PH.
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Affiliation(s)
- Jonathan R Weir-McCall
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, United Kingdom.
| | - Allan D Struthers
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, United Kingdom
| | - Brian J Lipworth
- Scottish Centre for Respiratory Research, Medical Research Institute, University of Dundee, Dundee, United Kingdom
| | - J Graeme Houston
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, United Kingdom
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13
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Blasco G, Balocco S, Puig J, Sánchez-González J, Ricart W, Daunis-i-Estadella J, Molina X, Pedraza S, Fernández-Real JM. Carotid pulse wave velocity by magnetic resonance imaging is increased in middle-aged subjects with the metabolic syndrome. Int J Cardiovasc Imaging 2014; 31:603-12. [DOI: 10.1007/s10554-014-0578-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 11/19/2014] [Indexed: 11/28/2022]
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14
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Quantitative magnetic resonance imaging of pulmonary hypertension: a practical approach to the current state of the art. J Thorac Imaging 2014; 29:68-79. [PMID: 24552882 DOI: 10.1097/rti.0000000000000079] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Pulmonary hypertension is a condition of varied etiology, commonly associated with poor clinical outcome. Patients are categorized on the basis of pathophysiological, clinical, radiologic, and therapeutic similarities. Pulmonary arterial hypertension (PAH) is often diagnosed late in its disease course, with outcome dependent on etiology, disease severity, and response to treatment. Recent advances in quantitative magnetic resonance imaging (MRI) allow for better initial characterization and measurement of the morphologic and flow-related changes that accompany the response of the heart-lung axis to prolonged elevation of pulmonary arterial pressure and resistance and provide a reproducible, comprehensive, and noninvasive means of assessing the course of the disease and response to treatment. Typical features of PAH occur primarily as a result of increased pulmonary vascular resistance and the resultant increased right ventricular (RV) afterload. Several MRI-derived diagnostic markers have emerged, such as ventricular mass index, interventricular septal configuration, and average pulmonary artery velocity, with diagnostic accuracy similar to that of Doppler echocardiography. Furthermore, prognostic markers have been identified with independent predictive value for identification of treatment failure. Such markers include large RV end-diastolic volume index, low left ventricular end-diastolic volume index, low RV ejection fraction, and relative area change of the pulmonary trunk. MRI is ideally suited for longitudinal follow-up of patients with PAH because of its noninvasive nature and high reproducibility and is advantageous over other biomarkers in the study of PAH because of its sensitivity to change in morphologic, functional, and flow-related parameters. Further study on the role of MRI image based biomarkers in the clinical environment is warranted.
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15
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Wibmer T, Rüdiger S, Scharnbeck D, Radermacher M, Markovic S, Stoiber KM, Rottbauer W, Schumann C. Pulmonary pulse transit time: a novel echocardiographic indicator of hemodynamic and vascular alterations in pulmonary hypertension and pulmonary fibrosis. Echocardiography 2014; 32:904-11. [PMID: 25264113 DOI: 10.1111/echo.12772] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
INTRODUCTION Pulse transit time (PTT) is generally assumed to be a surrogate marker for blood pressure changes and arterial stiffness. The aim was to evaluate whether pulmonary PTT (pPTT) may be noninvasively measured by Doppler echocardiography and whether it might be valuable for detecting pulmonary hemodynamic and vascular alterations. METHODS We defined pPTT as the interval between R-wave in the ECG and the corresponding peak late systolic pulmonary vein flow velocity measured by pw-Doppler in the pulmonary vein. Twelve consecutive patients with pulmonary hypertension (PH) and 12 subjects without any cardiovascular or respiratory disease were included in the study. All patients underwent a standard echocardiography including pPTT measurement. RESULTS In the PH group, 5 patients had idiopathic pulmonary arterial hypertension (WHO 1), 1 patient PH associated with connective tissue disease (CTD, WHO 1) without pulmonary fibrosis (PF), and 6 patients PH associated with PF either due to CTD (WHO 1) or other etiology (WHO 3). Mean pPTT was significantly shorter in the PH group (138.0 ± 16.78 msec; P < 0.0001) than in the control group (383.5 ± 23.84 msec). Within the PH group, the subgroup of patients with PF showed significantly shorter mean pPTT (93.50 ± 15.47 msec; P = 0.004) than the subgroup of patients with PH without PF (182.6 ± 14.35 msec). CONCLUSIONS The results of this study suggest that pPTT might be an interesting surrogate marker of pulmonary hemodynamic and vascular alterations in PH and PF. Further studies are warranted to evaluate the possible influence of other variables on pPTT.
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Affiliation(s)
- Thomas Wibmer
- Department of Internal Medicine II, University Hospital of Ulm, Ulm, Germany
| | - Stefan Rüdiger
- Department of Internal Medicine II, University Hospital of Ulm, Ulm, Germany
| | - Dominik Scharnbeck
- Department of Internal Medicine II, University Hospital of Ulm, Ulm, Germany
| | - Michael Radermacher
- Department of Internal Medicine II, University Hospital of Ulm, Ulm, Germany
| | - Sinisa Markovic
- Department of Internal Medicine II, University Hospital of Ulm, Ulm, Germany
| | - Kathrin M Stoiber
- Department of Internal Medicine II, University Hospital of Ulm, Ulm, Germany
| | - Wolfgang Rottbauer
- Department of Internal Medicine II, University Hospital of Ulm, Ulm, Germany
| | - Christian Schumann
- Department of Internal Medicine II, University Hospital of Ulm, Ulm, Germany
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16
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Assessment of pulmonary artery pulse wave velocity in children: An MRI pilot study. Magn Reson Imaging 2013; 31:1690-4. [DOI: 10.1016/j.mri.2013.08.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 08/06/2013] [Accepted: 08/20/2013] [Indexed: 11/22/2022]
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17
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Kopeć G, Moertl D, Jankowski P, Tyrka A, Sobień B, Podolec P. Pulmonary artery pulse wave velocity in idiopathic pulmonary arterial hypertension. Can J Cardiol 2012; 29:683-90. [PMID: 23260799 DOI: 10.1016/j.cjca.2012.09.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2012] [Revised: 09/16/2012] [Accepted: 09/25/2012] [Indexed: 10/27/2022] Open
Abstract
BACKGROUND Idiopathic pulmonary artery (PA) hypertension (IPAH) is associated with severe PA remodelling. Although the resulting increase in pulse wave velocity (PWV) might be of major pathophysiological relevance, little is known about PA-PWV in IPAH. The aim of this study was to characterize PA-PWV and its predictors in patients with IPAH. METHODS We studied 26 consecutive patients with incident IPAH aged 55.0 (45.0-66.0) years (62% female) and 10 control subjects without pulmonary hypertension. PA-PWV was measured invasively; PA wall thickness and diameter were assessed using intravascular and transthoracic ultrasonography. RESULTS PA-PWV was higher in IPAH than in control subjects (10.0 [7.5-14.0] m/s vs 3.5 [1.9-4.0] m/s; P < 0.001) as was also PA diameter and PA wall thickness. In IPAH patients, in univariate analysis PA-PWV was greater in men than in women and in patients with body mass index (BMI) < 25 kg/m(2) than with BMI ≥ 25 kg/m(2) and correlated positively with symptomatic disease duration, mean PA pressure, pulmonary vascular resistance, creatinine level, and negatively with low-density lipoprotein (LDL) cholesterol and triglyceride level but not with PA diameter or PA wall thickness. In multiple regression analysis mean PA pressure, LDL cholesterol level and BMI < 25 kg/m(2) were the main predictors of PA-PWV in IPAH patients (R(2) = 77%; P < 0.001). CONCLUSIONS PA-PWV is increased in IPAH patients. High PA pressure, low LDL cholesterol level, and BMI < 25 kg/m(2) explain most of its variability in this group.
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Affiliation(s)
- Grzegorz Kopeć
- Department of Cardiac and Vascular Diseases at John Paul II Hospital, Krakow, Poland.
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18
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Ibrahim ESH. Imaging sequences in cardiovascular magnetic resonance: current role, evolving applications, and technical challenges. Int J Cardiovasc Imaging 2012; 28:2027-47. [PMID: 22447266 DOI: 10.1007/s10554-012-0038-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 03/10/2012] [Indexed: 12/25/2022]
Abstract
Cardiovascular magnetic resonance (CMR) has been established as a powerful and comprehensive imaging modality for studying the cardiovascular (CV) system. Shortly after invention of magnetic resonance imaging, CMR applications and developments started to emerge, and they continue to evolve up to the present day. CMR has the advantages of high spatial resolution, enhanced tissue contrast, superior safety profile, and the plethora of physiological parameters that can be obtained. In the near future, CMR is expected to be the gold standard modality for comprehensive CV imaging. Specifically, CMR imaging sequences are increasingly growing in parallel with advancements in scanner hardware. Not only do CMR imaging sequences provide detailed anatomical information, but they also provide functional, perfusion, viability, hemodynamic, and metabolic information about the CV system. In this article, an up-to-date review of different CMR imaging sequences is presented. Each sequence is described along with typical imaging parameters, necessary image processing steps, derived CV parameters, and potential applications. The article then addresses advanced CMR imaging techniques and emerging applications. Finally, the challenges facing CMR imaging are discussed along with its expected future role.
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Affiliation(s)
- El-Sayed H Ibrahim
- Department of Radiology, University of Florida, 655 W 8th St, Jacksonville, FL 32209, USA.
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19
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Bradlow WM, R Gibbs JS, Mohiaddin RH. Cardiovascular magnetic resonance in pulmonary hypertension. J Cardiovasc Magn Reson 2012; 14:6. [PMID: 22257586 PMCID: PMC3305675 DOI: 10.1186/1532-429x-14-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2011] [Accepted: 01/18/2012] [Indexed: 11/29/2022] Open
Abstract
Pulmonary hypertension represents a group of conditions characterized by higher than normal pulmonary artery pressures. Despite improved treatments, outcomes in many instances remain poor. In recent years, there has been growing interest in the use of cardiovascular magnetic resonance (CMR) in patients with pulmonary hypertension. This technique offers certain advantages over other imaging modalities since it is well suited to the assessment of the right ventricle and the proximal pulmonary arteries. Reflecting the relatively sparse evidence supporting its use, CMR is not routinely recommended for patients with pulmonary hypertension. However, it is particularly useful in patient with pulmonary arterial hypertension associated with congenital heart disease. Furthermore, it has proven informative in a number of ways; illustrating how right ventricular remodeling is favorably reversed by drug therapies and providing explicit confirmation of the importance of the right ventricle to clinical outcome. This review will discuss these aspects and practical considerations before speculating on future applications.
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Affiliation(s)
- William M Bradlow
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK
- Pulmonary Hypertension Service, Hammersmith Hospital, London, UK
| | - J Simon R Gibbs
- Pulmonary Hypertension Service, Hammersmith Hospital, London, UK
| | - Raad H Mohiaddin
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK
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20
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Lammers S, Scott D, Hunter K, Tan W, Shandas R, Stenmark KR. Mechanics and Function of the Pulmonary Vasculature: Implications for Pulmonary Vascular Disease and Right Ventricular Function. Compr Physiol 2012; 2:295-319. [PMID: 23487595 DOI: 10.1002/cphy.c100070] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The relationship between cardiac function and the afterload against which the heart muscle must work to circulate blood throughout the pulmonary circulation is defined by a complex interaction between many coupled system parameters. These parameters range broadly and incorporate system effects originating primarily from three distinct locations: input power from the heart, hydraulic impedance from the large conduit pulmonary arteries, and hydraulic resistance from the more distal microcirculation. These organ systems are not independent, but rather, form a coupled system in which a change to any individual parameter affects all other system parameters. The result is a highly nonlinear system which requires not only detailed study of each specific component and the effect of disease on their specific function, but also requires study of the interconnected relationship between the microcirculation, the conduit arteries, and the heart in response to age and disease. Here, we investigate systems-level changes associated with pulmonary hypertensive disease progression in an effort to better understand this coupled relationship.
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Affiliation(s)
- Steven Lammers
- Department of Cardiovascular Pulmonary Research, University of Colorado Denver, Aurora, Colorado ; Department of Bioengineering, University of Colorado Denver, Aurora, Colorado
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21
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Black blood MRI has diagnostic and prognostic value in the assessment of patients with pulmonary hypertension. Eur Radiol 2011; 22:695-702. [DOI: 10.1007/s00330-011-2306-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 09/03/2011] [Accepted: 09/28/2011] [Indexed: 02/06/2023]
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22
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Ibrahim ESH, Miller AB, White RD. The relationship between aortic stiffness and E/A filling ratio and myocardial strain in the context of left ventricular diastolic dysfunction in heart failure with normal ejection fraction: insights from magnetic resonance imaging. Magn Reson Imaging 2011; 29:1222-34. [PMID: 21907518 DOI: 10.1016/j.mri.2011.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 07/28/2011] [Accepted: 08/04/2011] [Indexed: 11/27/2022]
Abstract
The purpose of this study is to investigate the relationship between aortic stiffness and diastolic dysfunction in heart failure with normal ejection fraction (HFNEF) and compare the results to normal subjects using magnetic resonance imaging (MRI). Sixteen human subjects (eight HFNEF and eight volunteers) were scanned on a 3.0-T MRI system. Aortic stiffness was assessed using pulse wave velocity (PWV). Left ventricle (LV) diastolic function was assessed by the early/atrial (E/A) filling ratio and different myocardial strain components. The results showed that, in HFNEF, a major part of LV filling occurred later during the atrial filling phase. The E/A ratio was less than 1 in HFNEF and greater than 1 in volunteers. Left ventricular myocardial dynamic strain range (difference between end-diastolic and end-systolic strains) was reduced in HFNEF, with less relaxation (strain rate) during the diastolic phase. Aortic PWV was higher in HFNEF than in volunteers due to less vessel compliance. The E/A ratio and myocardial strain measurements showed inverse correlations with aortic stiffness in HFNEF. The resulting inter- and intraobserver variabilities showed no bias between repeated cardiovascular measurements. In conclusion, a comprehensive MRI exam was developed for assessing patients with HFNEF. Heart failure with normal EF is associated with impaired LV diastolic function and significant ventricular and aortic stiffening. The degree of aortic stiffness involvement suggests reduced aortic compliance as a major factor in HFNEF.
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Ibrahim ESH, Shaffer JM, White RD. Assessment of pulmonary artery stiffness using velocity-encoding magnetic resonance imaging: evaluation of techniques. Magn Reson Imaging 2011; 29:966-74. [PMID: 21641745 DOI: 10.1016/j.mri.2011.04.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2010] [Revised: 01/18/2011] [Accepted: 04/12/2011] [Indexed: 11/20/2022]
Abstract
The loss of pulmonary artery (PA) compliance has significant pathophysiological effect on the right ventricle. Noninvasive and reliable assessment of PA wall stiffness would be an essential determiner of right heart load and a clinically useful factor to assess cardiovascular risk. Two MRI techniques have been proposed for assessing PA stiffness by measuring pulse wave velocity (PWV): transit time (TT) and flow area (QA). However, no data are available that compares the two techniques and evaluates their performance, especially over a wide range of PWV values or at 3.0-T, which is the purpose of the present study. Thirty-three patients with different heart conditions were imaged using optimized high-temporal resolution and high-spatial resolution velocity-encoding MRI sequences. Statistical analysis was conducted to study intermethod, interobserver and intraobserver variabilities. The PWV measurements using TT and QA techniques showed good agreement (P>0.1). The Bland-Altman analysis showed negligible differences between the two methods (mean±S.D.=0.11±0.35 m/s, correlation coefficient r=0.94). The repeated measurements showed low interobserver and intraobserver variabilities, although the S.D. of the differences was larger in the QA technique. The mean±S.D. of the TT/QA measurement differences were -0.05±0.2/0.0±0.36 m/s and 0.02±0.26/0.02±0.39 m/s for the interobserver and intraobserver differences, respectively. In conclusion, each technique has its own advantages and disadvantages. The two techniques result in similar measurements, although the QA method is more subjective due to its dependency on operator intervention.
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Affiliation(s)
- El-Sayed H Ibrahim
- Department of Radiology, University of Florida, 655 W. 8th St., Jacksonville, FL 32209, USA.
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Markl M, Wallis W, Brendecke S, Simon J, Frydrychowicz A, Harloff A. Estimation of global aortic pulse wave velocity by flow-sensitive 4D MRI. Magn Reson Med 2010; 63:1575-82. [PMID: 20512861 DOI: 10.1002/mrm.22353] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The aim of this study was to determine the value of flow-sensitive four-dimensional MRI for the assessment of pulse wave velocity as a measure of vessel compliance in the thoracic aorta. Findings in 12 young healthy volunteers were compared with those in 25 stroke patients with aortic atherosclerosis and an age-matched normal control group (n = 9). Results from pulse wave velocity calculations incorporated velocity data from the entire aorta and were compared to those of standard methods based on flow waveforms at only two specific anatomic landmarks. Global aortic pulse wave velocity was higher in patients with atherosclerosis (7.03 +/- 0.24 m/sec) compared to age-matched controls (6.40 +/- 0.32 m/sec). Both were significantly (P < 0.001) increased compared to younger volunteers (4.39 +/- 0.32 m/sec). Global aortic pulse wave velocity in young volunteers was in good agreement with previously reported MRI studies and catheter measurements. Estimation of measurement inaccuracies and error propagation analysis demonstrated only minor uncertainties in measured flow waveforms and moderate relative errors below 16% for aortic compliance in all 46 subjects. These results demonstrate the feasibility of pulse wave velocity calculation based on four-dimensional MRI data by exploiting its full volumetric coverage, which may also be an advantage over standard two-dimensional techniques in the often-distorted route of the aorta in patients with atherosclerosis.
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Affiliation(s)
- Michael Markl
- Department of Radiology, Medical Physics, University Hospital, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany.
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25
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Ibrahim ESH, Johnson KR, Miller AB, Shaffer JM, White RD. Measuring aortic pulse wave velocity using high-field cardiovascular magnetic resonance: comparison of techniques. J Cardiovasc Magn Reson 2010; 12:26. [PMID: 20459799 PMCID: PMC2874535 DOI: 10.1186/1532-429x-12-26] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Accepted: 05/11/2010] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND The assessment of arterial stiffness is increasingly used for evaluating patients with different cardiovascular diseases as the mechanical properties of major arteries are often altered. Aortic stiffness can be noninvasively estimated by measuring pulse wave velocity (PWV). Several methods have been proposed for measuring PWV using velocity-encoded cardiovascular magnetic resonance (CMR), including transit-time (TT), flow-area (QA), and cross-correlation (XC) methods. However, assessment and comparison of these techniques at high field strength has not yet been performed. In this work, the TT, QA, and XC techniques were clinically tested at 3 Tesla and compared to each other. METHODS Fifty cardiovascular patients and six volunteers were scanned to acquire the necessary images. The six volunteer scans were performed twice to test inter-scan reproducibility. Patient images were analyzed using the TT, XC, and QA methods to determine PWV. Two observers analyzed the images to determine inter-observer and intra-observer variabilities. The PWV measurements by the three methods were compared to each other to test inter-method variability. To illustrate the importance of PWV using CMR, the degree of aortic stiffness was assessed using PWV and related to LV dysfunction in five patients with diastolic heart failure patients and five matched volunteers. RESULTS The inter-observer and intra-observer variability results showed no bias between the different techniques. The TT and XC results were more reproducible than the QA; the mean (SD) inter-observer/intra-observer PWV differences were -0.12(1.3)/-0.04(0.4) for TT, 0.2(1.3)/0.09(0.9) for XC, and 0.6(1.6)/0.2(1.4) m/s for QA methods, respectively. The correlation coefficients (r) for the inter-observer/intra-observer comparisons were 0.94/0.99, 0.88/0.94, and 0.83/0.92 for the TT, XC, and QA methods, respectively. The inter-scan reproducibility results showed low variability between the repeated scans (mean (SD) PWV difference = -0.02(0.4) m/s and r = 0.96). The inter-method variability results showed strong correlation between the TT and XC measurements, but less correlation with QA: r = 0.95, 0.87, and 0.89, and mean (SD) PWV differences = -0.12(1.0), 0.8(1.7), and 0.65(1.6) m/s for TT-XC, TT-QA, and XC-QA, respectively. Finally, in the group of diastolic heart failure patient, PWV was significantly higher (6.3 +/- 1.9 m/s) than in volunteers (3.5 +/- 1.4 m/s), and the degree of LV diastolic dysfunction showed good correlation with aortic PWV. CONCLUSIONS In conclusion, while each of the studied methods has its own advantages and disadvantages, at high field strength, the TT and XC methods result in closer and more reproducible aortic PWV measurements, and the associated image processing requires less user interaction, than in the QA method. The choice of the analysis technique depends on the vessel segment geometry and available image quality.
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Affiliation(s)
- El-Sayed H Ibrahim
- Department of Radiology, University of Florida College of Medicine, Jacksonville, Florida, USA
| | - Kevin R Johnson
- Department of Radiology, University of Florida College of Medicine, Jacksonville, Florida, USA
| | - Alan B Miller
- Department of Medicine, University of Florida College of Medicine, Jacksonville, Florida, USA
| | - Jean M Shaffer
- Department of Radiology, University of Florida College of Medicine, Jacksonville, Florida, USA
| | - Richard D White
- Department of Radiology, University of Florida College of Medicine, Jacksonville, Florida, USA
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Taviani V, Patterson AJ, Graves MJ, Hardy CJ, Worters P, Sutcliffe MP, Gillard JH. Accuracy and repeatability of fourier velocity encoded M-mode and two-dimensional cine phase contrast for pulse wave velocity measurement in the descending aorta. J Magn Reson Imaging 2010; 31:1185-94. [DOI: 10.1002/jmri.22143] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Urbina EM, Williams RV, Alpert BS, Collins RT, Daniels SR, Hayman L, Jacobson M, Mahoney L, Mietus-Snyder M, Rocchini A, Steinberger J, McCrindle B. Noninvasive assessment of subclinical atherosclerosis in children and adolescents: recommendations for standard assessment for clinical research: a scientific statement from the American Heart Association. Hypertension 2009; 54:919-50. [PMID: 19729599 DOI: 10.1161/hypertensionaha.109.192639] [Citation(s) in RCA: 467] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Deterioration in endothelial function and arterial stiffness are early events in the development of cardiovascular diseases. In adults, noninvasive measures of atherosclerosis have become established as valid and reliable tools for refining cardiovascular risk to target individuals who need early intervention. With limited pediatric data, the use of these techniques in children and adolescents largely has been reserved for research purposes. Therefore, this scientific statement was written to (1) review the current literature on the noninvasive assessment of atherosclerosis in children and adolescents, (2) make recommendations for the standardization of these tools for research, and (3) stimulate further research with a goal of developing valid and reliable techniques with normative data for noninvasive clinical evaluation of atherosclerosis in pediatric patients. Precise and reliable noninvasive tests for atherosclerosis in youth will improve our ability to estimate future risk for heart attack and stroke. Currently, large longitudinal studies of cardiovascular risk factors in youth, such as the Bogalusa and Muscatine studies, lack sufficient adult subjects experiencing hard outcomes, such as heart attack and stroke, to produce meaningful risk scores like those developed from Framingham data.
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Bradlow WM, Gatehouse PD, Hughes RL, O'Brien AB, Gibbs JSR, Firmin DN, Mohiaddin RH. Response. J Magn Reson Imaging 2009. [DOI: 10.1002/jmri.21631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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29
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Laffon E, Laurent F, Ducassou D, Marthan R. Transit-time method to demonstrate whether or not an impedance matching occurs at the pulmonary junction. J Magn Reson Imaging 2009; 29:498; author reply 499. [DOI: 10.1002/jmri.21632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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30
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McIntyre CW, John SG, Jefferies HJ. Advances in the cardiovascular assessment of patients with chronic kidney disease. NDT Plus 2008; 1:383-391. [PMID: 28657024 PMCID: PMC5477876 DOI: 10.1093/ndtplus/sfn146] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Accepted: 08/11/2008] [Indexed: 12/11/2022] Open
Abstract
Cardiovascular mortality is grossly elevated in patients with chronic kidney disease (CKD), and is associated with a wide variety of structural and functional abnormalities. These issues have driven additional attempts to further characterise these abnormalities to elucidate the pathophysiology involved, assess individual risk and/or target and monitor therapies specifically directed at the cardiovascular (CV) system. This review aims to assess the techniques that are currently available for the study of the CV system. This includes conventional assessments of the whole CV system from heart to peripheral microcirculation (although not deal with VC assessment), as well as the key functional consequences relating to stress induced cardiovascular reserve, perfusion and vasoregulation. In addition this review will introduce a variety of techniques aiming to expand the envelope of conventional measurements.
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Affiliation(s)
| | - Stephen G. John
- Department of Renal Medicine, Derby Hospitals NHS Foundation Trust, Derby, UK
| | - Helen J. Jefferies
- Department of Renal Medicine, Derby Hospitals NHS Foundation Trust, Derby, UK
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