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Akbulut O, Ertugrul I, Pehlivantürk-Kızılkan M, Oztürk M, Sencelikel T, Derman O, Akgül S. Are adolescents with premenstrual disorder at risk for cardiac arrhythmias? J Obstet Gynaecol Res 2024. [PMID: 39254151 DOI: 10.1111/jog.16084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Accepted: 08/27/2024] [Indexed: 09/11/2024]
Abstract
BACKGROUND One of the most commonly experienced symptoms of premenstrual disorder (PMD) is anxiety, and there is a notable rise in sympathomimetic activity in this patient group. Studies have linked fluctuations in systemic autonomic tone to electrocardiography (ECG) changes. This study aims to investigate the relationship between anxiety, a common symptom of PMD, and alterations in QT dispersion (QTd) and P-wave dispersion (Pd) in adolescent females. METHODS This cross-sectional study included female adolescents aged 12-18 with regular menstruation for at least 3 months. Participants completed the premenstrual syndrome scale (PMSS) and were divided into two groups, PMD and control, according to the PMSS score. A standard 12-lead body surface ECG was performed and QTd and Pd values were determined in each participant. RESULTS Of the 43 participants, 27 were categorized into the PMD group, with a mean age of 15.15 ± 1.43 years. Age at menarche and menstrual cycle patterns were comparable between the PMD and control groups. Statistical analysis revealed significantly higher Pmin (p = 0.010) and Pd values (p < 0.001) in the PMD group compared to controls. A positive correlation between PMSS scores and Pd (p = 0.049) was also observed. CONCLUSIONS Changes in atrial conduction and ventricular repolarization due to the pathophysiology of PMD may increase the risk of developing atrial and ventricular tachyarrhythmias over time. Screening patients with PMD using an ECG may be useful in identifying potentially at-risk adolescents.
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Affiliation(s)
- Ozlem Akbulut
- Department of Pediatrics, Baskent University Medical Faculty, Ankara, Turkey
| | - Ilker Ertugrul
- Department of Paediatric Cardiology, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | | | - Musa Oztürk
- Department of Paediatric Cardiology, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Tugce Sencelikel
- Department of Biostatistics, Ankara Medipol University Medical Faculty, Ankara, Turkey
| | - Orhan Derman
- Division of Adolescent Medicine, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Sinem Akgül
- Division of Adolescent Medicine, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
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2
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Prajapati C, Koivumäki J, Pekkanen-Mattila M, Aalto-Setälä K. Sex differences in heart: from basics to clinics. Eur J Med Res 2022; 27:241. [PMID: 36352432 PMCID: PMC9647968 DOI: 10.1186/s40001-022-00880-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 10/24/2022] [Indexed: 11/11/2022] Open
Abstract
Sex differences exist in the structure and function of human heart. The patterns of ventricular repolarization in normal electrocardiograms (ECG) differ in men and women: men ECG pattern displays higher T-wave amplitude and increased ST angle. Generally, women have longer QT duration because of reduced repolarization reserve, and thus, women are more susceptible for the occurrence of torsades de pointes associated with drugs prolonging ventricular repolarization. Sex differences are also observed in the prevalence, penetrance and symptom severity, and also in the prognosis of cardiovascular disease. Generally, women live longer, have less clinical symptoms of cardiac diseases, and later onset of symptoms than men. Sex hormones also play an important role in regulating ventricular repolarization, suggesting that hormones directly influence various cellular functions and adrenergic regulation. From the clinical perspective, sex-based differences in heart physiology are widely recognized, but in daily practice, cardiac diseases are often underdiagnosed and untreated in the women. The underlying mechanisms of sex differences are, however, poorly understood. Here, we summarize sex-dependent differences in normal cardiac physiology, role of sex hormones, and differences in drug responses. Furthermore, we also discuss the importance of human induced pluripotent stem cell-derived cardiomyocytes in further understanding the mechanism of differences in women and men.
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Affiliation(s)
- Chandra Prajapati
- Faculty of Medicine and Health Technology, Tampere University, Arvo Ylpön Katu 34, 33520 Tampere, Finland
| | - Jussi Koivumäki
- Faculty of Medicine and Health Technology, Tampere University, Arvo Ylpön Katu 34, 33520 Tampere, Finland
| | - Mari Pekkanen-Mattila
- Faculty of Medicine and Health Technology, Tampere University, Arvo Ylpön Katu 34, 33520 Tampere, Finland
| | - Katriina Aalto-Setälä
- Faculty of Medicine and Health Technology, Tampere University, Arvo Ylpön Katu 34, 33520 Tampere, Finland
- Heart Center, Tampere University Hospital, Ensitie 4, 33520 Tampere, Finland
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3
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Lazzarini E, Lodrini AM, Arici M, Bolis S, Vagni S, Panella S, Rendon-Angel A, Saibene M, Metallo A, Torre T, Vassalli G, Ameri P, Altomare C, Rocchetti M, Barile L. Stress-induced premature senescence is associated with a prolonged QT interval and recapitulates features of cardiac aging. Theranostics 2022; 12:5237-5257. [PMID: 35836799 PMCID: PMC9274748 DOI: 10.7150/thno.70884] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 06/11/2022] [Indexed: 01/12/2023] Open
Abstract
Rationale: Aging in the heart is a gradual process, involving continuous changes in cardiovascular cells, including cardiomyocytes (CMs), namely cellular senescence. These changes finally lead to adverse organ remodeling and resulting in heart failure. This study exploits CMs from human induced pluripotent stem cells (iCMs) as a tool to model and characterize mechanisms involved in aging. Methods and Results: Human somatic cells were reprogrammed into human induced pluripotent stem cells and subsequently differentiated in iCMs. A senescent-like phenotype (SenCMs) was induced by short exposure (3 hours) to doxorubicin (Dox) at the sub-lethal concentration of 0.2 µM. Dox treatment induced expression of cyclin-dependent kinase inhibitors p21 and p16, and increased positivity to senescence-associated beta-galactosidase when compared to untreated iCMs. SenCMs showed increased oxidative stress, alteration in mitochondrial morphology and depolarized mitochondrial membrane potential, which resulted in decreased ATP production. Functionally, when compared to iCMs, SenCMs showed, prolonged multicellular QTc and single cell APD, with increased APD variability and delayed afterdepolarizations (DADs) incidence, two well-known arrhythmogenic indexes. These effects were largely ascribable to augmented late sodium current (INaL) and reduced delayed rectifier potassium current (Ikr). Moreover sarcoplasmic reticulum (SR) Ca2+ content was reduced because of downregulated SERCA2 and increased RyR2-mediated Ca2+ leak. Electrical and intracellular Ca2+ alterations were mostly justified by increased CaMKII activity in SenCMs. Finally, SenCMs phenotype was furtherly confirmed by analyzing physiological aging in CMs isolated from old mice in comparison to young ones. Conclusions: Overall, we showed that SenCMs recapitulate the phenotype of aged primary CMs in terms of senescence markers, electrical and Ca2+ handling properties and metabolic features. Thus, Dox-induced SenCMs can be considered a novel in vitro platform to study aging mechanisms and to envision cardiac specific anti-aging approach in humans.
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Affiliation(s)
- Edoardo Lazzarini
- Cardiovascular Theranostics, Istituto Cardiocentro Ticino, Laboratories for Translational Research, Ente Ospedaliero Cantonale, Bellinzona, Switzerland
| | - Alessandra Maria Lodrini
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milano, Italy.,Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Martina Arici
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milano, Italy
| | - Sara Bolis
- Cardiovascular Theranostics, Istituto Cardiocentro Ticino, Laboratories for Translational Research, Ente Ospedaliero Cantonale, Bellinzona, Switzerland.,Cellular and Molecular Cardiology, Istituto Cardiocentro Ticino, Laboratories for Translational Research, Ente Ospedaliero Cantonale, Bellinzona, Switzerland
| | - Sara Vagni
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milano, Italy
| | - Stefano Panella
- Cardiovascular Theranostics, Istituto Cardiocentro Ticino, Laboratories for Translational Research, Ente Ospedaliero Cantonale, Bellinzona, Switzerland
| | - Azucena Rendon-Angel
- Cardiovascular Theranostics, Istituto Cardiocentro Ticino, Laboratories for Translational Research, Ente Ospedaliero Cantonale, Bellinzona, Switzerland.,Faculty of Biomedical Sciences, Università della Svizzera Italiana, Lugano, Switzerland
| | - Melissa Saibene
- Department of Earth and Environmental Sciences, Università degli Studi di Milano-Bicocca, Milano, Italy
| | - Alessia Metallo
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milano, Italy
| | - Tiziano Torre
- Department of Cardiac Surgery Istituto Cardiocentro Ticino, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Giuseppe Vassalli
- Cellular and Molecular Cardiology, Istituto Cardiocentro Ticino, Laboratories for Translational Research, Ente Ospedaliero Cantonale, Bellinzona, Switzerland.,Faculty of Biomedical Sciences, Università della Svizzera Italiana, Lugano, Switzerland
| | - Pietro Ameri
- Cardiovascular Disease Unit, IRCCS Ospedale Policlinico, Genova, Italy.,Department of Internal Medicine, University of Genova, Genova, Italy
| | - Claudia Altomare
- Cardiovascular Theranostics, Istituto Cardiocentro Ticino, Laboratories for Translational Research, Ente Ospedaliero Cantonale, Bellinzona, Switzerland
| | - Marcella Rocchetti
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milano, Italy.,✉ Corresponding authors: Lucio Barile, PhD. Istituto Cardiocentro Ticino, Laboratories for Translational Research, EOC Via Chiesa 5, 6500 Bellinzona, Switzerland. +41 586667104 ; Marcella Rocchetti, PhD. University of Milano-Bicocca, Dept. of Biotechnology and Biosciences, P.za della Scienza 2, 20126 Milano, Italy. +39 0264483313
| | - Lucio Barile
- Cardiovascular Theranostics, Istituto Cardiocentro Ticino, Laboratories for Translational Research, Ente Ospedaliero Cantonale, Bellinzona, Switzerland.,Faculty of Biomedical Sciences, Università della Svizzera Italiana, Lugano, Switzerland.,Institute of Life Science, Scuola Superiore Sant'Anna, Pisa, Italy.,✉ Corresponding authors: Lucio Barile, PhD. Istituto Cardiocentro Ticino, Laboratories for Translational Research, EOC Via Chiesa 5, 6500 Bellinzona, Switzerland. +41 586667104 ; Marcella Rocchetti, PhD. University of Milano-Bicocca, Dept. of Biotechnology and Biosciences, P.za della Scienza 2, 20126 Milano, Italy. +39 0264483313
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Gurok MG, Korkmaz H, Yıldız S, Bakış D, Atmaca M. QT and P-wave dispersion during the manic phase of bipolar disorder. Neuropsychiatr Dis Treat 2019; 15:1805-1811. [PMID: 31308673 PMCID: PMC6613347 DOI: 10.2147/ndt.s208253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Accepted: 06/10/2019] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND AND AIM Patients with bipolar disorder (BD) are at increased risk for cardiovascular diseases and complications. This increased risk is considered to be associated with the autonomic nervous system (ANS) abnormalities. However, there is little or no documentation of the relationship between this increased risk and the phases of BD. In this study, we aimed to compare the changes in the QT dispersion (QTd) and P-wave dispersion (Pd), which are predictors of sudden cardiac death and atrial fibrillation, between the patients with manic BD and healthy controls. PARTICIPANTS AND METHODS The study included a patient group of 44 patients (26 female and 18 male) that were hospitalized due to a diagnosis of manic BD and met the inclusion criteria, and a control group of 34 age- and gender-matched healthy individuals (21 female and 13 male) with no history of psychiatric and neurological disorders. The QTd and Pd values were determined in each participant by performing the standard 12-lead body surface electrocardiography (ECG). RESULTS The principal electrocardiographic indicators including corrected maximum QT interval, corrected QT dispersion, and minimum P-wave duration significantly increased in the patient group compared to the control group (t=2.815, p<0.01; t=4.935, p<0.001; t=3.337, p<0.001, respectively). CONCLUSION The results indicated that patients with manic BD are at increased risk for cardiovascular autonomic dysfunction. Therefore, clinicians should be more careful about ECG changes and related possible cardiac conduction problems such as cardiac arrthythmias in patients with manic BD. Further longitudinal studies are needed to investigate BD and its phases (depression, mania, and hypomania) with regard to ANS and cardiac abnormalities.
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Affiliation(s)
- Mehmet Gurkan Gurok
- Fırat University, School of Medicine, Department of Psychiatry, Elazig, Turkey
| | - Hasan Korkmaz
- Fırat University, School of Medicine, Department of Cardiology, Elazig, Turkey
| | - Sevler Yıldız
- Fırat University, School of Medicine, Department of Psychiatry, Elazig, Turkey
| | - Dilek Bakış
- Fırat University, School of Medicine, Department of Psychiatry, Elazig, Turkey
| | - Murad Atmaca
- Fırat University, School of Medicine, Department of Psychiatry, Elazig, Turkey
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5
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Effect of age and gender on the QTc-interval in healthy individuals and patients with long-QT syndrome. Trends Cardiovasc Med 2017; 28:64-75. [PMID: 28869094 DOI: 10.1016/j.tcm.2017.07.012] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 07/26/2017] [Accepted: 07/27/2017] [Indexed: 12/15/2022]
Abstract
Age- and gender-related differences in QTc-interval are most likely the result of changes in sex-specific hormones. Although the exact mechanisms and pathophysiology of sex hormones on the QTc-interval are not known, testosterone appears to shorten the QTc-interval. In females, however, there is a more complex interaction between progesterone and estrogen. In patients with an impaired repolarization, such as long-QT syndrome (LQTS), the effect of these sex hormones on the QTc-interval is more pronounced with a differing sensitivity between the LQTS genotypes.
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6
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Abstract
Objective: To report a case of torsade de pointes in a patient receiving moxifloxacin. Case Summary: An 87-year-old woman was admitted to the hospital for pneumonia, and antibiotic therapy with intravenous moxifloxacin 400 mg/day was initiated. The patient was noted to have significant QTc interval prolongation 2 hours after administration of moxifloxacin and developed torsade de pointes 8–10 hours after moxifloxacin administration. She was converted back to normal sinus rhythm after a precordial thump. Moxifloxacin was discontinued, and the woman's QTc interval subsequently returned to baseline. Discussion: Torsade de pointes is a life-threatening arrhythmia that has previously been associated with the use of fluoroquinolones. Minimal information is available regarding the risk of torsade de pointes with moxifloxacin. According to the Naranjo probability scale, the episode in this case was probably related to administration of intravenous moxifloxacin. Conclusions: In patients with underlying risk factors for a prolonged QT interval, the use of moxifloxacin can lengthen the interval further and ultimately trigger episodes of torsade de pointes. Moxifloxacin administration in these patients therefore should be administered and monitored judiciously.
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Affiliation(s)
- Krista M Dale
- Division of Cardiology, School of Pharmacy, University of Connecticut, Hartford, CT, USA
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7
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Lutfi MF. QT Interval Derived Measurements in Patients with Cardiac Syndrome X Compared to Coronary Artery Disease. Front Physiol 2016; 7:422. [PMID: 27708590 PMCID: PMC5030246 DOI: 10.3389/fphys.2016.00422] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 09/06/2016] [Indexed: 11/18/2022] Open
Abstract
Previous studies assessing effect of ischemia on ventricular repolarization are mostly directed toward patients with coronary artery disease (CAD); however, similar reports on cardiac syndrome X (CSX) are scarce. Whether microvascular dysfunction of CSX and ischemia induced by CAD produce comparable effect on ventricular repolarization is unclear and deserve further studies. In the present study, ECG measures of ventricular repolarization were compared between CAD and CSX patients (40 subjects in each group). Following evaluation of sociodemographic characteristics, medical and past medical history, a resting ECG was used to assess measurements of ventricular repolarization in each patient, namely, QT interval (QT), corrected QT interval (QTc), QT dispersion (QTd), corrected QT dispersion (QTcd), adjacent QT dispersion (AdQTd), QT dispersion ratio (QTdR), JT dispersion (JTd), and Corrected JT dispersion (JTcd). Results showed comparable QT intervals and QTd in CAD and CSX patients even after adjustment for the possible variations in gender, age and body mass index of the studied groups. Although JTd was increased in CSX subjects (26.6 ± 7.2 ms) compared with CAD patients (22.7 ± 6.5 ms, p = 0.019), statistical significance disappeared after correcting JT for variations in heart rate. QT and QTc were significantly below 440 ms in CAD as well as CSX patients (p < 0.001). In contrast, maximum QTd, maximum QTcd and AdQTd of CAD and CSX patients were significantly above 440 ms (p < 0.001). The means of JTd and JTcd were significantly above 22 ms and 24 ms respectively (p < 0.001, p = 0.001) in CSX but not CAD patients (p = 0.529, p = 0.281). The present findings clearly demonstrate comparable measures of ventricular repolarization in CAD and CSX patients and consequently an equal risk of cardiac events in both groups.
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Affiliation(s)
- Mohamed F Lutfi
- Department of Physiology, Faculty of Medicine and Health Sciences, Al-Neelain University Khartoum, Sudan
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8
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Increased P-wave and QT dispersions necessitate long-term follow-up evaluation of Down syndrome patients with congenitally normal hearts. Pediatr Cardiol 2014; 35:1344-8. [PMID: 24859169 DOI: 10.1007/s00246-014-0934-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 05/15/2014] [Indexed: 10/25/2022]
Abstract
Reports state that Down syndrome (DS) patients with congenitally normal hearts might experience the development of cardiac abnormalities such as cardiac autonomic dysfunction, valvular lesions, bradycardia, and atrioventricular block. However, the presence of any difference in terms of P-wave dispersion (PWd) and QT dispersion (QTd) was not evaluated previously. This study prospectively investigated 100 DS patients with structurally normal hearts and 100 age- and sex-matched healthy control subjects. Standard 12-lead electrocardiograms were used to assess and compare P-wave and QT durations together with PWd and QTd. The median age of the DS patients and control subjects was 48 months. Heart rates and P-wave and QT dispersions were significantly greater in the DS group than in the control group (113 ± 22.9 vs 98.8 ± 16.6 bpm, p < 0.001; 31.3 ± 9.5 vs 24 ± 8.6 ms, p < 0.001; and 46.6 ± 15.9 vs 26 ± 9.1 ms, p < 0.001, respectively). A positive correlation was found between PWd and age in the DS patients (p < 0.05; r = 0.2). All children with DS should be followed up carefully with electrocardiography in terms of increased P-wave and QT dispersions even in the absence of concomitant congenital heart disease for management of susceptibility to arryhthmias.
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9
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Fijorek K, Tanner FC, Stähli BE, Gielerak G, Krzesinski P, Uzieblo-Zyczkowska B, Smurzynski P, Stanczyk A, Stolarz-Skrzypek K, Kawecka-Jaszcz K, Jastrzebski M, Podolec M, Kopec G, Stanula B, Kocowska M, Tylutki Z, Polak S. Model of the distribution of diastolic left ventricular posterior wall thickness in healthy adults and its impact on the behavior of a string of virtual cardiomyocytes. J Cardiovasc Transl Res 2014; 7:507-17. [PMID: 24676501 PMCID: PMC4098050 DOI: 10.1007/s12265-014-9558-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 03/05/2014] [Indexed: 11/28/2022]
Abstract
Correlation of the thickness of the left ventricular posterior wall (LVPWd) with various parameters, including age, gender, weight and height, was investigated in this study using regression models. Multicenter derived database comprised over 4,000 healthy individuals. The developed models were further utilized in the in vitro-in vivo (IVIV) translation of the drug cardiac safety data with use of the mathematical model of human cardiomyocytes operating at the virtual healthy population level. LVPWd was assumed to be equivalent to the length of one-dimensional string of virtual cardiomyocyte cells which was presented, as other physiological factors, to be a parameter influencing the simulated pseudo-ECG (pseudoelectrocardiogram), QTcF and ∆QTcF, both native and modified by exemplar drug (disopyramide) after I Kr current disruption. Simulation results support positive correlation between the LVPWd and QTcF/∆QTc. Developed models allow more detailed description of the virtual population and thus inter-individual variability influence on the drug cardiac safety.
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Affiliation(s)
- Kamil Fijorek
- Department of Statistics, Cracow University of Economics, Krakow, Poland
| | - Felix C. Tanner
- Cardiology, Cardiovascular Center, University Hospital Zurich, Zurich, Switzerland
| | - Barbara E. Stähli
- Cardiology, Cardiovascular Center, University Hospital Zurich, Zurich, Switzerland
| | - Grzegorz Gielerak
- Department of Cardiology and Internal Medicine, Military Institute of Medicine, Warsaw, Poland
| | - Pawel Krzesinski
- Department of Cardiology and Internal Medicine, Military Institute of Medicine, Warsaw, Poland
| | | | - Pawel Smurzynski
- Department of Cardiology and Internal Medicine, Military Institute of Medicine, Warsaw, Poland
| | - Adam Stanczyk
- Department of Cardiology and Internal Medicine, Military Institute of Medicine, Warsaw, Poland
| | - Katarzyna Stolarz-Skrzypek
- First Department of Cardiology, Interventional Electrocardiology and Hypertension, Jagiellonian University Medical College, Krakow, Poland
| | - Kalina Kawecka-Jaszcz
- First Department of Cardiology, Interventional Electrocardiology and Hypertension, Jagiellonian University Medical College, Krakow, Poland
| | - Marek Jastrzebski
- First Department of Cardiology, Interventional Electrocardiology and Hypertension, University Hospital, Krakow, Krakow, Poland
| | - Mateusz Podolec
- Department of Coronary Artery Disease, Jagiellonian University Medical College at the John Paul II Hospital, Krakow, Poland
| | - Grzegorz Kopec
- Department of Cardiac and Vascular Diseases, Jagiellonian University Medical College and Centre for Rare Cardiovascular Diseases at the John Paul II Hospital, Krakow, Poland
| | | | | | - Zofia Tylutki
- Unit of Pharmacoepidemiology and Pharmacoeconomics, Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| | - Sebastian Polak
- Unit of Pharmacoepidemiology and Pharmacoeconomics, Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
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Buttà C, Tuttolomondo A, Casuccio A, Di Raimondo D, Giarrusso L, Miceli G, Lo Vecchio S, Canino B, Licata G, Pinto A. Use of QT intervals for a more accurate diagnose of syncope and evaluation of syncope severity. Int J Clin Pract 2014; 68:864-70. [PMID: 24548671 DOI: 10.1111/ijcp.12387] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND This study aimed to evaluate the use of QT intervals, their diagnostic predictive value in patients with syncope and their relationship with syncope severity. METHODS One hundred and forty nine patients with a diagnosis of syncope were admitted to Internal Medicine departments at the University of Palermo, Italy, between 2006 and 2012, and 140 control subjects hospitalised for other causes were enrolled. QT maximum, QT minimum, QTpeak, QT corrected, QT dispersion and Tpeak-to-Tend interval were compared between two groups. The paper medical records were used for scoring with San Francisco Syncope Rule (SFSR), Evaluation of Guidelines in SYncope Study (EGSYS) score and Osservatorio Epidemiologico sulla Sincope nel Lazio (OESIL) risk score. RESULTS Mean QTc (p < 0.0005), mean QTmax (p < 0.0005), mean QTdisp (p < 0.0005), mean QTpeak (p = 0.005) and mean TpTe (p = 0.018) were significantly longer in patients with syncope compared with control subjects. A QTc > 424.8 ms (sensibility: 81.88 - specificity: 57.86) showed the greatest predictive value for diagnosis of syncope. On the EGSYS score and on the OESIL score, QTc was significantly prolonged in high-risk patients compared with low-risk patients. On the San Francisco Syncope Rule, QTc and QTdisp were significantly prolonged in high-risk patients compared with low-risk patients. CONCLUSION Mean QTc, mean QTdisp, mean TpTe, mean QTmax and mean QTpeak were significantly longer in patients with syncope compared with control subjects. Furthermore, prolonged QTc and QTdisp were associated with major severe syncope according to San Francisco Syncope Rule, EGSYS and OESIL risk scores.
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Affiliation(s)
- C Buttà
- U.O.C. Medicina Vascolare, Dipartimento Biomedico di Medicina Interna e Specialistica, Università degli Studi di, Palermo, Italy
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Changes in QTc interval in the citalopram for agitation in Alzheimer's disease (CitAD) randomized trial. PLoS One 2014; 9:e98426. [PMID: 24914549 PMCID: PMC4051660 DOI: 10.1371/journal.pone.0098426] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 04/19/2014] [Indexed: 01/08/2023] Open
Abstract
Background A Food and Drug Administration (FDA) safety communication in August 2011 warned that citalopram was associated with a dose dependent risk of QT prolongation and recommended dose restriction in patients over the age of 60 but did not provide data for this age group. Methods CitAD was a randomized, double-masked, placebo-controlled, multicenter clinical trial for agitation in Alzheimer's disease (AD). Participants were assigned to citalopram (target dose of 30 mg/day) or placebo in a 1∶1 ratio. 186 people, 181 of whom were over the age of 60, having probable AD with clinically significant agitation were recruited from September 2009 to January 2013. After the FDA safety communication about citalopram, ECG was added to the required study procedures before enrollment and repeated at week 3 to monitor change in QTc interval. Forty-eight participants were enrolled after enhanced monitoring began. Results Citalopram treatment was associated with a larger increase in QTc interval than placebo (difference in week 3 QTc adjusting for baseline QTc: 18.1 ms [95% CI: 6.1, 30.1]; p = 0.004). More participants in the citalopram group had an increase ≥30 ms from baseline to week 3 (7 in citalopram versus 1 in placebo; Fisher's exact p = 0.046), but only slightly more in the citalopram group met a gender-specific threshold for prolonged QTc (450 ms for males; 470 ms for females) at any point during follow-up (3 in citalopram versus 1 in placebo, Fisher's exact p = 0.611). One of the citalopram participants who developed prolonged QTc also displayed ventricular bigeminy. No participants in either group had a cardiovascular-related death. Conclusion Citalopram at 30 mg/day was associated with improvement in agitation in patients with AD but was also associated with QT prolongation. Trial Registration ClinicalTrials.gov NCT00898807
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Claudio BDQ, Costa MAN, Penna F, Konder MT, Celoria BMJ, Souza LLD, Pozzan R, Schneider RS, Albuquerque FN, Albuquerque DC. Impact of psychotropic drugs on QT interval dispersion in adult patients. Arq Bras Cardiol 2014; 102:465-72. [PMID: 24830389 PMCID: PMC4051449 DOI: 10.5935/abc.20140055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 11/26/2013] [Indexed: 11/20/2022] Open
Abstract
Background Drug-induced increase in QT dispersion has been associated with potentially fatal
ventricular arrhythmias. Little is known about the use of psychotropic substances,
alone or in combination with other drugs on QT dispersion. Objectives To evaluate the impact of psychotropic drugs on QT interval dispersion in adults.
Methods An observational cohort study was designed involving 161 patients hospitalized
from an emergency department at a tertiary hospital, divided into psychotropic
users or non-users. Demographic, clinical, laboratory data and drugs used on a
regular basis were collected on admission, in addition to 12-lead
electrocardiogram with QT dispersion measurement. Results QT dispersion was significantly higher in the psychotropic user group compared to
non-users (69.25 ± 25.5 ms vs. 57.08 ± 23.4 ms; p = 0.002). The QT interval
corrected by Bazzett formula was also higher in the psychotropic drugs user group,
with statistical significance. (439.79 ± 31.14 ms vs. 427.71 ± 28.42 ms; p =
0.011). A regression analysis model showed a positive association between the
number of psychotropic drugs used and QT interval dispersion, with r = 0.341 and p
< 0.001. Conclusions The use of psychotropic drugs was associated with increased QT dispersion and this
increase was accentuated, as the number of psychotropic drugs used was higher.
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Affiliation(s)
| | | | - Filipe Penna
- Hospital Copa D'Or/IDOR, Rio de Janeiro, RJ, Brasil
| | | | | | | | - Roberto Pozzan
- Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
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13
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Ciobanu A, Gheorghe GS, Ababei M, Deaconu M, Ilieşiu AM, Bolohan M, Păun N, Nicolae C, Nanea IT. Dispersion of ventricular repolarization in relation to cardiovascular risk factors in hypertension. J Med Life 2014; 7:545-50. [PMID: 25713619 PMCID: PMC4316136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Accepted: 09/29/2014] [Indexed: 11/08/2022] Open
Abstract
RATIONALE Hypertension associates with sudden cardiac death, its relationship with ventricular arrhythmias being demonstrated by multiple studies, an increased dispersion of repolarization being an important arrhythmogenesis mechanism. Only a small percentage of hypertensive patients presents increased blood pressure values exclusively as risk factor, most of them presenting additional risk factors that reinforce each other leading to increased total cardiovascular risk. AIM to analyze the dispersion of repolarization parameters (QT interval, QT dispersion, Tpeak-Tend interval (Tpe), Tpe/QT, Tpe dispersion) in relation to cardiovascular risk factors, as well as total cardiovascular risk estimated by SCORE model, in mild to moderate essential hypertension. METHOD 62 consecutive patients, mean age 55±11 years, were evaluated by 24 hours Holter electrocardiography monitoring. Manual measurement of dispersion of repolarization parameters was performed. RESULTS Based on SCORE model, 33.9% patients presented low risk, 40.3% moderate risk, 16.1% high risk and 9.1% very high risk. Age had a positive correlation with QT and reverse correlations with QT dispersion, Tpe and Tpe/QT in lead V1. Tpe/QT showed significantly higher values in men versus women. Glucose metabolism disorders associated with higher values of QT and Tpe dispersion were present. However, dispersion of repolarization parameters was similar between risk categories assessed by SCORE model, Tpe in lead V3 correlated significantly with SCORE score. CONCLUSIONS In mild to moderate hypertension, the dispersion of repolarization parameters is influenced by age, gender and glucose metabolism disorders. Among these, Tpe in lead V3 correlates with total cardiovascular risk assessed by SCORE model.
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Affiliation(s)
- A Ciobanu
- “Theodor Burghele” Clinical Hospital, Bucharest, Romania
| | - GS Gheorghe
- “Theodor Burghele” Clinical Hospital, Bucharest, Romania,“Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - M Ababei
- “Theodor Burghele” Clinical Hospital, Bucharest, Romania
| | - M Deaconu
- “Theodor Burghele” Clinical Hospital, Bucharest, Romania
| | - AM Ilieşiu
- “Theodor Burghele” Clinical Hospital, Bucharest, Romania,“Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - M Bolohan
- “Theodor Burghele” Clinical Hospital, Bucharest, Romania,“Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - N Păun
- “Theodor Burghele” Clinical Hospital, Bucharest, Romania,“Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - C Nicolae
- “Theodor Burghele” Clinical Hospital, Bucharest, Romania,“Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - IT Nanea
- “Theodor Burghele” Clinical Hospital, Bucharest, Romania,“Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
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Hezzell MJ, Dennis SG, Humm K, Agee L, Boswood A. Relationships between heart rate and age, bodyweight and breed in 10,849 dogs. J Small Anim Pract 2013; 54:318-24. [PMID: 23662951 DOI: 10.1111/jsap.12079] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To evaluate relationships between heart rate and clinical variables in healthy dogs and dogs examined at a referral hospital. METHODS Clinical data were extracted from the electronic patient records of a first opinion group (5000 healthy dogs) and a referral hospital (5849 dogs). Univariable and multi-variable general linear models were used to assess associations between heart rate and clinical characteristics. Separate multi-variable models were constructed for first opinion and referral populations. RESULTS In healthy dogs, heart rate was negatively associated with bodyweight (P<0.001) but was higher in Chihuahuas. The mean difference in heart rate between a 5 and 55 kg dog was 10.5 beats per minute. In dogs presenting to a referral hospital, heart rate was negatively associated with bodyweight (P<0.001) and the following breeds; border collie, golden retriever, Labrador retriever, springer spaniel and West Highland white terrier and positively associated with age, admitting service (emergency and critical care, emergency first opinion and cardiology) and the following breeds; Cavalier King Charles spaniel, Staffordshire bull terrier and Yorkshire terrier. CLINICAL SIGNIFICANCE Bodyweight, age, breed and disease status all influence heart rate in dogs, although these factors account for a relatively small proportion of the overall variability in heart rate.
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Affiliation(s)
- M J Hezzell
- Department of Veterinary Clinical Sciences, The Royal Veterinary College, Hawkshead Lane, North Mymms, Hertfordshire, AL9 7TA
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Abstract
Levosimendan is a novel calcium sensitizing agent in development for the treatment of acute and chronic heart failure. The agent increases myocardial force without increasing myocyte calcium concentrations, thus reducing the possibility for myocardial necrosis. In addition, the agent also causes vasodilation of coronary and peripheral vessels to improve coronary blood flow and reduce afterload. The short half-life is a benefit for intravenous administration but could be problematic for the drug's use in chronic heart failure. The risk of the development of arrhythmias from levosimendan appears small secondary to an increase in the QTc interval of 15 msec but needs to be evaluated in light of the ability of levosimendan to open adenosine triphosphate (ATP)-sensitive potassium channels. In addition, the agent has not been studied in patients with additional risks for torsades de pointes. Levosimendan has been shown to have beneficial survival effects in several populations; its use improves patient outcomes relative to the standard of care and has the potential to reduce hospital costs associated with heart failure.
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Affiliation(s)
- Brian F McBride
- Hartford Hospital Drug Information Center, 80 Seymour Street, P.O. Box 5037, Hartford, CT 06102-5037, USA
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Abstract
Although cardiac arrhythmia had long been considered a predominantly male syndrome, it is now clear that arrhythmia is also a primary cause of mortality in women. Notably, the manifestation of specific arrhythmia syndromes appears to be gender specific. In particular, female sex is an independent risk factor for development of torsade de pointes (TdP) arrhythmias not only in congenital long QT syndromes but also in acquired long QT syndromes which occur as adverse effects of existing drugs. Males, on the other hand, are more likely to develop Brugada syndrome. Recent clinical and experimental studies suggest that these differences may stem from intrinsic sex differences in cardiac tissue. These include fundamental electrical differences resulting from variable ion channel expression and diverse sex hormonal regulation via long-term genomic and acute nongenomic pathways, and sex differences in drug responses and metabolisms. Undoubtedly, determining the effect of gender on cardiac function will be difficult and require sophisticated methodologies. However, gender differences underlying predilection to distinct arrhythmia syndromes must be revealed so that new therapeutic strategies that take gender into account can be applied to at-risk patients.
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Affiliation(s)
- Junko Kurokawa
- Department of Bio-Informational Pharmacology, Tokyo Medical and Dental University, Tokyo, Japan.
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Suzuki Y, Ono S, Sugai T, Fukui N, Watanabe J, Tsuneyama N, Sawamura K, Someya T. Dose-dependent effects of olanzapine on QT intervals and plasma prolactin levels in Japanese patients with stable schizophrenia. Hum Psychopharmacol 2011; 26:440-3. [PMID: 21823168 DOI: 10.1002/hup.1218] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 06/01/2011] [Accepted: 06/09/2011] [Indexed: 11/05/2022]
Abstract
OBJECTIVES There have been few reports regarding olanzapine (OLZ)-related QT prolongation and hyperprolactinemia. This study evaluated the dose-dependent effect of OLZ on QT interval and plasma prolactin (PRL) level in a single sample of patients with schizophrenia. METHODS Twenty-six subjects treated with varying starting doses of OLZ were enrolled in the study. Following baseline assessments, which included completion of the Brief Psychiatric Rating Scale (BPRS), measurements of Body Mass Index (BMI), QT interval, electrolytes, fasting plasma glucose, PRL, hemoglobin A1c (HbA1c), total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL), and low density lipoprotein (LDL), the dose of OLZ was increased for each subject. The same parameters were evaluated following the increased dose treatment. RESULTS A significant decrease was observed in BPRS score (p = 0.01) following treatment with an increased dose of OLZ. Significant increases were observed in BMI (p = 0.032), QTc (p = 0.031), and plasma PRL level (p = 0.028). The mean values of electrolytes, fasting plasma glucose, HbA1c, TC, TG, HDL and LDL treatment were unchanged by the switch to increased-dose OLZ treatment. CONCLUSION We have demonstrated the dose-dependent effect of OLZ on the QT interval and the plasma PRL level of patients with schizophrenia.
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Affiliation(s)
- Yutaro Suzuki
- Department of Psychiatry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
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18
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Huang JH, Tsai JC, Hsu MI, Chen YJ. Cardiac conductive disturbance in patients with polycystic ovary syndrome. Gynecol Endocrinol 2010; 26:883-8. [PMID: 20500103 DOI: 10.3109/09513590.2010.487593] [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] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Polycystic ovary syndrome (PCOS) is the most common endocrine abnormality of reproductive-aged women and increases the risk of cardiovascular disease. However, the effects of PCOS on electrocardiograms (ECGs) are not fully elucidated. The aim of this study was to evaluate the characteristics of ECGs in patients with PCOS. METHODS This study included 24 patients with PCOS and 12 patients without PCOS. The heart rate, PR interval, QRS duration, Sokolow-Lyon voltage (SV1 + RV5/6), Cornell voltage (RaVL + SV3), QT interval and QTc interval were measured in 12-lead ECGs. RESULTS The QRS duration was wider in patients with PCOS than those without PCOS (91 ± 8 vs. 81 ± 10 ms, p < 0.05). The heart rate, PR interval, Sokolow-Lyon voltage, product of the QRS duration times Cornell voltage combination, QT interval, QTc interval, QT dispersion and QTc dispersion were similar between the two groups. CONCLUSIONS PCOS is associated with a widening QRS duration, which may contribute to its increased cardiovascular risks.
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Affiliation(s)
- Jen-Hung Huang
- Division of Cardiovascular Medicine, Taipei Medical University-Wan Fang Hospital, Taipei, Taiwan
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Pshenichnikov I, Shipilova T, Karai D, Riiupulk J, Veski K, Pilt K, Kaik J. Association between ventricular repolarization and main cardiovascular risk factors. SCAND CARDIOVASC J 2010; 45:33-40. [PMID: 21114455 DOI: 10.3109/14017431.2010.532232] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To assess the association between QT interval, QT dispersion and main cardiovascular risk factors in Tallinn women population aged 50-69 years. DESIGN A random sample of Tallinn population, 302 women underwent 12-lead rest ECG, echocardiography and laboratory tests. Corrected QT interval and QT dispersion were calculated. RESULTS The significant correlation coefficients for corrected QT interval and dispersion were observed with systolic, diastolic, pulse pressure, blood pressure value grade, heart rate, left ventricular mass index, and total cardiovascular risk grade. According to the data of multiple logistic regression, risk factors independently associated with prolonged QTc and QTD were arterial hypertension: OR 2.69, p < 0.001 and OR 3.29, p < 0.001, pulse pressure ≥ 60 mm Hg: OR 2.62, p < 0.001 and OR 3.04, p < 0.001, age > 65 years: OR 2.44, p < 0.001 and OR 1.91, p < 0.01, family history of cardiovascular disease: OR 2.02, p < 0.01 and OR 2.48, p < 0.001, left ventricular hypertrophy: OR 2.78, p < 0.001 and OR 5.29, p < 0.001. Multivariable linear regression data showed an independent association between corrected QT interval, QT dispersion and systolic blood pressure: β = 0.32, p < 0.001 and β = 0.39, p=0.003, pulse pressure: β = 0.21, p = 0.004 and β = 0.27, p < 0.001, blood pressure value grade: β = 0.35, p < 0.001 (for QT dispersion only), heart rate: β = 0.21, p < 0.001 and β = -0.19, p = 0.001, left ventricular mass index: β = 0.23, p < 0.001 and β = 0.27, p < 0.001. CONCLUSION In Tallinn women population, electrocardiographic parameters reflecting ventricular repolarization are associated with systolic blood pressure, pulse pressure, blood pressure value grade, heart rate and left ventricular hypertrophy.
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Affiliation(s)
- Igor Pshenichnikov
- Centre of Cardiology, Technomedicum, Tallinn University of Technology, Tallinn, Estonia.
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Dogan EA, Dogan U, Yıldız GU, Akıllı H, Genc E, Genc BO, Gok H. Evaluation of cardiac repolarization indices in well-controlled partial epilepsy: 12-Lead ECG findings. Epilepsy Res 2010; 90:157-63. [DOI: 10.1016/j.eplepsyres.2010.04.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 04/12/2010] [Accepted: 04/24/2010] [Indexed: 01/10/2023]
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Dimopoulos S, Nicosia F, Turini D, Zulli R. Prognostic evaluation of QT-dispersion in elderly hypertensive and normotensive patients. Pacing Clin Electrophysiol 2009; 32:1381-7. [PMID: 19712075 DOI: 10.1111/j.1540-8159.2009.02510.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND QT-corrected interval dispersion (QTcD) is an indirect index of increased heterogeneity of ventricular repolarization. However, the prognostic value of (QTcD) in elderly hypertensive and normotensive patients has not been thoroughly investigated yet. METHODS The study population consisted of 60 consecutive patients (34 males/26 females; mean age: 63+/-11 years) with mild to moderate essential arterial hypertension and 48 consecutive age-matched healthy subjects (24 males/24 females; 65+/-16 years). QTcD was measured by a 12-lead electrocardiogram (ECG) as the difference between maximum and minimum QT-interval, corrected for heart rate. Ventricular arrhythmias were recorded by a 24-hour Holter ECG and classified by a modified Lown's score (range: 0-6). Left ventricular mass was measured echocardiographically and indexed by body surface area [left ventricular mass index (LVMI)]. Nine patients were lost during the follow-up period. Patients were followed up for 54+/-9 months, and the primary end-point was the major cardiovascular events (including cardiac mortality). RESULTS Major cardiovascular events occurred in 22 patients (22%). Patients with QTcD>or=45 ms (n=35) had a higher rate of major cardiovascular events (43% vs 11%; log rank: 14.8; P<0.001), a higher LVMI (146+/-29 vs 104+/-21 g/m2; P<0.001), greater values of systolic and diastolic blood pressure (154+/-16 vs 144+/-18 mmHg; P<0.01 and 92+/-10 vs 88+/-8 mmHg; P<0.05, respectively), a higher number of premature ventricular beats (354+/-870 vs 113+/-301; P<0.05), and a greater Lown's score (3.7+/-1.9 vs 1.4+/-1.8; P<0.05) than patients with QTcD<45 ms. QTcD (>or=or<45 ms) was an independent predictor of major cardiovascular events (odds ratio: 4.9; 95% confidence interval: 2.0-12.1; P=0.001) after adjustment for LVMI, Lown's score (>or=or<3), age (>or=or<65 years), and QTc max (>or=or<437 ms). CONCLUSIONS QTcD is an independent predictor of major cardiovascular events in elderly hypertensive and normotensive patients and might be used in their risk stratification.
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Affiliation(s)
- Stavros Dimopoulos
- Clinical Therapeutics, University of Athens, Alexandra Hospital, Athens, Greece.
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Koide T, Shiba M, Tanaka K, Muramatsu M, Ishida S, Kondo Y, Watanabe K. Severe QT interval prolongation associated with moxifloxacin: a case report. CASES JOURNAL 2008; 1:409. [PMID: 19099576 PMCID: PMC2621134 DOI: 10.1186/1757-1626-1-409] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Accepted: 12/19/2008] [Indexed: 11/11/2022]
Abstract
INTRODUCTION The QT interval prolongation is an adverse effect associated with moxifloxacin. This adverse effect can lead to potentially life-threatening arrhythmias such as Torsades de pointes. We describe a case of severe QT interval prolongation associated with moxifloxacin which may cause the development of Torsades de pointes. There have been no reported case of severe corrected QT interval prolongation caused by moxifloxacin in the patient of normal heart rate. CASE PRESENTATION In an 85-year-old Japanese woman, oral moxifloxacin 400 mg daily was initiated for the forearm cellulitis. On the sixth day of oral moxifloxacin administration, monitor electrocardiogram showed prolongation of the corrected QT interval to 523 ms at a rate of 40 beats/min. Electrocardiogram before moxifloxacin therapy showed the corrected QT interval to 460 ms at a rate of 72 beats/min. On the sixth day after moxifloxacin discontinuance, monitor electrocardiogram showed the corrected QT interval to 432 ms at a rate of 70 beats/min. CONCLUSION This case suggests that electrocardiogram monitoring during moxifloxacin therapy may be necessary in the patients even if they do not have high risk factors for QT interval prolongation.
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Affiliation(s)
- Tetsuro Koide
- Department of Pharmacy, Kuwana Municipal Hospital, 430 Kitabessyo, Kuwana 511-0819, Japan
| | - Masato Shiba
- Department of Neurosurgery, Kuwana Municipal Hospital, 430 Kitabessyo, Kuwana 511-0819, Japan
| | - Katsuhiro Tanaka
- Department of Neurosurgery, Kuwana Municipal Hospital, 430 Kitabessyo, Kuwana 511-0819, Japan
| | - Masatoshi Muramatsu
- Department of Neurosurgery, Kuwana Municipal Hospital, 430 Kitabessyo, Kuwana 511-0819, Japan
| | - Satoshi Ishida
- Department of Internal Medicine, Kuwana Municipal Hospital, 430 Kitabessyo, Kuwana 511-0819, Japan
| | - Yoshihiro Kondo
- Department of Pharmacy, Kuwana Municipal Hospital, 430 Kitabessyo, Kuwana 511-0819, Japan
| | - Keiko Watanabe
- Department of Pharmacy, Kuwana Municipal Hospital, 430 Kitabessyo, Kuwana 511-0819, Japan
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Dimopoulos S, Nicosia F, Donati P, Prometti P, De Vecchi M, Zulli R, Grassi V. QT dispersion and left ventricular hypertrophy in elderly hypertensive and normotensive patients. Angiology 2008; 59:605-12. [PMID: 18388029 DOI: 10.1177/0003319707310276] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Inhomogeneity of ventricular repolarization as detected by QT dispersion may be a potential leading mechanism of sudden death in hypertensive and normotensive (age related) left ventricular hypertrophy. Aim of this study was to investigate QT dispersion, ventricular arrhythmias, and left ventricular mass index in elderly hypertensive and normotensive patients. Study population consisted of 60 consecutive patients (sex: 34 men/26 women; age: 63 +/- 11 years) with essential arterial hypertension and 48 age and sex-matched control subjects (24 men/24 women; 64 +/- 16 years). Measurements included QTc dispersion, ventricular arrhythmias, and left ventricular hypertrophy. Hypertensive patients had greater left ventricular mass index (P = .006) and higher QTc dispersion (P = .004) than controls. Left ventricular hypertrophy was diagnosed in 57 (31 men/26 women) of all subjects. These patients had higher blood pressure (P < .05), Lown's score (P < .001), and QTc dispersion (P < .001). QTc dispersion and Lown's score were independent predictors of left ventricular mass index (P < .001). Conclusively, QTc dispersion is a strong indicator of left ventricular mass index and might be used in risk stratification of hypertensive and normotensive elderly patients.
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Affiliation(s)
- Stavros Dimopoulos
- Department of Clinical Therapeutics, Alexandra Hospital, University of Athens, Athens, Greece.
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Fabijanic D, Culic V, Bozic I, Miric D, Stipic SS, Radic M, Vucinovic Z. Gender differences in in-hospital mortality and mechanisms of death after the first acute myocardial infarction. Ann Saudi Med 2006; 26:455-60. [PMID: 17143022 PMCID: PMC6074327 DOI: 10.5144/0256-4947.2006.455] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND There are conflicting data about gender differences in short-term mortality after acute myocardial infarction (AMI) after adjusting for age and other prognostic factors. Therefore, we investigated the risk profile, clinical presentation, in-hospital mortality and mechanisms of death in women and men after the first AMI. METHODS The data were obtained from a chart review of 3382 consecutive patients, 1184 (35%) women (69.7+/-10.9 years) and 2198 (65%) men (63.5+/-11.8 years) with a first AMI. The effect of gender and its interaction with age, risk factors and thrombolytic therapy on overall mortality and mechanisms of death were examined using logistic regression. RESULTS Unadjusted in-hospital mortality was higher in women (OR 1.77, 95% CI 1.47-2.15). Adjustment that included both age only and age and other baseline differences (hypertension, diabetes mellitus, hypercholesterolemia, smoking, AMI type, AMI site, mean peak CK value, thrombolytic therapy) decreased the magnitude of the relative risk of women to men but did not eliminate it (OR 1.26, 95% CI 1.03-1.54 and OR 1.31 95% CI 1.03-1.66, respectively). Multivariate analysis revealed that female gender was an independent predictor of in-hospital mortality after the first AMI. Women were dying more often because of mechanical complications - refractory pulmonary edema and cardiogenic shock (P=0.02) or electromechanical dissociation (P=0.03), and men were dying mostly by arrhythmic death, primary ventricular tachycardia/fibrillation (P=0.002). Female gender was independently associated with mechanical death (OR 1.56, 95% CI 1.35-2.58; P=0.01) and anterior AMI was independently associated with arrhythmic death (OR 0.54, 95% CI 0.34-0.86; P=0.01). CONCLUSION Our results demonstrate significant differences in mechanisms of in-hospital death after the first AMI in women and men, suggesting the possibility that higher in-hospital mortality in women exists primarily because of the postponing AMI death due to the gender-related differences in susceptibility to cardiac arrhythmias following acute coronary events.
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Affiliation(s)
- Damir Fabijanic
- Department of Internal Medicine, University Hospital Split, Spincicev, Split, Croatia.
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Friberg LE, Isbister GK, Duffull SB. Pharmacokinetic-pharmacodynamic modelling of QT interval prolongation following citalopram overdoses. Br J Clin Pharmacol 2006; 61:177-90. [PMID: 16433872 PMCID: PMC1884996 DOI: 10.1111/j.1365-2125.2005.02546.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
AIMS To develop a pharmacokinetic-pharmacodynamic model describing the time-course of QT interval prolongation after citalopram overdose and to evaluate the effect of charcoal on the relative risk of developing abnormal QT and heart-rate combinations. METHODS Plasma concentrations and electrocardiograph (ECG) data from 52 patients after 62 citalopram overdose events were analysed in WinBUGS using a Bayesian approach. The reported doses ranged from 20 to 1700 mg and on 17 of the events a single dose of activated charcoal was administered. The developed pharmacokinetic-pharmacodynamic model was used for predicting the probability of having abnormal combinations of QT-RR, which was assumed to be related to an increased risk for torsade de pointes (TdP). RESULTS The absolute QT interval was related to the observed heart rate with an estimated individual heart-rate correction factor [alpha = 0.36, between-subject coefficient of variation (CV) = 29%]. The heart-rate corrected QT interval was linearly dependent on the predicted citalopram concentration (slope = 40 ms l mg(-1), between-subject CV = 70%) in a hypothetical effect-compartment (half-life of effect-delay = 1.4 h). The heart-rate corrected QT was predicted to be higher in women than in men and to increase with age. Administration of activated charcoal resulted in a pronounced reduction of the QT prolongation and was shown to reduce the risk of having abnormal combinations of QT-RR by approximately 60% for citalopram doses above 600 mg. CONCLUSION Citalopram caused a delayed lengthening of the QT interval. Administration of activated charcoal was shown to reduce the risk that the QT interval exceeds a previously defined threshold and therefore is expected to reduce the risk of TdP.
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Affiliation(s)
- Lena E Friberg
- School of Pharmacy, University of Queensland, Brisbane, Australia.
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Yavuz B, Deveci OS, Yavuz BB, Halil M, Aytemir K, Cankurtaran M, Kabakci G, Kaya B, Ariogul S, Oto A. QT dispersion increases with aging. Ann Noninvasive Electrocardiol 2006; 11:127-31. [PMID: 16630086 PMCID: PMC7313311 DOI: 10.1111/j.1542-474x.2006.00093.x] [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: 12/19/2022] Open
Abstract
BACKGROUND Age-related changes in cardiovascular system are well-known. Arrhythmias in elderly patients constitute most of the urgencies, consultations, or hospitalizations. QT dispersion (QTd) is a simple noninvasive arrhythmogenic marker to demonstrate the electrical instability of the heart. The aim of this study was to investigate how QTd changes with increasing age by calculating the QTd in the elderly and younger subjects. METHODS One hundred and forty-six consecutive subjects (62 males and 84 females; age range: 18-82 years) were enrolled in the study. Sixty-seven of the subjects were 65 years and over (mean age, 70 +/- 4), 79 were younger than 65 (mean age, 37 +/- 11). A 12-lead ECG was recorded. The longest and the shortest QT intervals were measured manually on these ECG recordings. QTd was calculated from the formula, QTd = QTmax - QTmin. RESULTS Demographic features were similar between the two groups. QTd of the elderly group was found to be significantly higher than the younger group (35.6 +/- 15.6 in elderly, 24.2 +/- 12.4 in younger group, P < 0.001). A positive relationship was found between QTd and age (r = 0.415, P < 0.001). QTd was greater in female than in male (31.9 +/- 16.7 ms vs 26.0 +/- 11.3 ms, respectively, P = 0.018). CONCLUSIONS Our study shows that QTd increases with advancing age. We think that long-term follow-up of these patients would be useful to show if there is any relationship between the clinical outcomes and the increase in QTd.
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Affiliation(s)
- Bunyamin Yavuz
- Department of Cardiology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
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Min B, McBride BF, Kardas MJ, Ismali A, Sinha V, Kluger J, White CM. Electrocardiographic effects of an Ephedra-Free, multicomponent weight-loss supplement in healthy volunteers. Pharmacotherapy 2005; 25:654-9. [PMID: 15899726 DOI: 10.1592/phco.25.5.654.63581] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
STUDY OBJECTIVE Metabolife 356, an ephedra-containing weight-loss product, substantially increases the corrected QT (QTc) interval. Metabolife Ephedra Free, a similar supplement, contains caffeine and extracts of green tea, garcinia cambogia, and yerba mate. Its electrocardiographic (ECG) effects are not known. Therefore, we sought to determine the effect of this supplement on the QTc interval. DESIGN Randomized, double-blind, placebo-controlled, crossover study. SETTING University of Connecticut, Storrs Campus. SUBJECTS Twenty healthy volunteers. Intervention. A single capsule containing half the normal recommended dose of Metabolife Ephedra Free or matching placebo was administered in crossover fashion, with a 7-day washout period between treatments. MEASUREMENTS AND MAIN RESULTS Baseline and three postdose ECG measurements were obtained, and QTc intervals were measured over a 5-hour study period. No significant differences in the QTc interval or other ECG variables were observed between the Metabolife Ephedra Free and placebo groups. CONCLUSION At half the recommended single dose, Metabolife Ephedra Free does not affect the QTc interval or other ECG variables over 5 hours. Dose-response studies and studies of longer duration should be conducted.
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Affiliation(s)
- Bokyung Min
- School of Pharmacy, University of Connecticut, Storrs, 06102, USA
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McBride BF, White CM. Critical differences among beta-adrenoreceptor antagonists in myocardial failure: debating the MERIT of COMET. J Clin Pharmacol 2005; 45:6-24. [PMID: 15601801 DOI: 10.1177/0091270004269841] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In the United States, carvedilol and metoprolol (tartrate or succinate) are the most commonly employed beta-adrenoreceptor antagonists for the treatment of heart failure. However, use of these agents in patients with heart failure remains extremely low despite overwhelming evidence of their beneficial short- and long-term effects. Because the myocardial pathophysiology associated with heart failure involves not only beta-1 adrenoreceptors but also beta-2 and alpha-1 adrenoreceptors, this indicates a more complex disease process that may require pan-receptor antagonism to provide optimal clinical benefit. Relative to metoprolol (tartrate or succinate), carvedilol represents an extremely complex molecular entity that not only possesses the ability to antagonize all of the principle adrenoreceptors involved in heart failure but also reduces oxidative stress and provides an antiarrhythmic benefit independent of beta-adrenoreceptor antagonism. Taken together, an interesting pharmacologic premise for the superiority of carvedilol relative to metoprolol (tartrate) may exist, but the lack of clinical trials comparing an optimal dose of either extended-release metoprolol (ie, succinate) or immediate-release metoprolol (ie, tartrate) to carvedilol limits the clinical application of the pharmacologic differences between the agents.
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Affiliation(s)
- Brian F McBride
- Division of Clinical Pharmacology, College of Medicine, Vanderbilt University, Nashville, Tennessee, USA
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Abstract
BACKGROUND AND AIMS In the last few years there has been active interest in the study of QT interval dispersion (QT-d) calculated from the 12-lead ECG, as a non-invasive method of investigating the homogeneity of ventricular recovery time. The aim of this study was to evaluate QT interval dispersion, analyzing in particular gender and age relationships. Discussion of its electrophysiologic and clinic meaning is still open; moreover, the method must be standardized and normal values should be clearly defined. METHODS The two common indices, range and standard deviation of QT, were taken into account. The study sample is part of the population-based Italian Longitudinal Study on Aging (ILSA) with individuals older than 64 years. Three groups were identified by clinical data: 256 healthy subjects, 98 patients with only cardiac diseases, and 472 patients with only hypertension. RESULTS Age (< 75 and > 75) and gender subgroups were considered, showing that age and gender influence the QT-d differently in the three groups. QT-d indices were influenced in the healthy group by gender (p < 0.001), in the cardiopathy group by age (p < 0.001), and in the hypertension group by age (p < 0.02) and gender (p < 0.01). Then the two gender groups were considered separately. In the female group, QT-d increased significantly with age only in the healthy group (p < 0.02), whereas in the male group it increased significantly in the cardiopathy and hypertension groups (p < 0.01). CONCLUSIONS The two QT-d indices behaved in a very similar way in all the comparisons. In older people, gender and age influenced the three clinical selected groups differently. However, it was shown that is not possible to indicate a clear, definite threshold value classifying with accuracy a single subject in the clinical groups; and a clear-cut, direct clinic application is still doubtful.
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Affiliation(s)
- Giovanni Bortolan
- Institute of Biomedical Engineering, Italian National Research Council (ISIB-CNR), Padova, Italy.
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Malkin CJ, Morris PD, Pugh PJ, English KM, Channer KS. Effect of testosterone therapy on QT dispersion in men with heart failure. Am J Cardiol 2003; 92:1241-3. [PMID: 14609611 DOI: 10.1016/j.amjcard.2003.07.044] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The effects of testosterone on cardiac electrophysiology are poorly described. In this study we report the effect of physiologic testosterone therapy in 2 cohorts of men, the first with stable coronary disease and the second with congestive heart failure. Testosterone reduced QT dispersion in the heart failure cohort; no other effects were observed.
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Affiliation(s)
- Chris J Malkin
- Department of Cardiology, Royal Hallamshire Hospital, Sheffield, United Kingdom
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Egawa H, Minami J, Fujii K, Hamaguchi S, Okuda Y, Kitajima T. QT interval and QT dispersion increase in the elderly during laparoscopic cholecystectomy: a preliminary study. Can J Anaesth 2002; 49:805-9. [PMID: 12374708 DOI: 10.1007/bf03017412] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
PURPOSE To compare the influence of a longer duration of intraperitoneal CO2 insufflation with head-up tilt on electrocardiogram indices during laparoscopic cholecystectomy between elderly and younger patients. METHODS Twelve elderly and 12 younger patients were studied. In all patients, intraperitoneal CO2 insufflation was performed for more than 150 min in the head-up position. RR interval, QT interval, the rate-corrected QT (QTc) interval, QT dispersion (QTD) and the rate-corrected QTD (QTcD) were measured. RESULTS The QT interval and the QTc interval increased significantly from 120 to 150 min after CO2 insufflation in the elderly. The QTD and QTcD increased significantly during CO2 insufflation in both groups. Those were significantly greater in the elderly than in younger patients from 120 to 150 min after CO2 insufflation. CONCLUSION Longer duration of CO2 insufflation with head-up tilt is associated with a prolongation of the QT interval and the QTD in elderly patients. The clinical significance of these findings remains to be determined.
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Affiliation(s)
- Hirotoshi Egawa
- Department of Anesthesiology, Dokkyo University School of Medicine, Mibu, Tochigi, Japan.
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Abstract
QT dispersion, defined as the maximal-minus-minimal QT interval on a 12-lead electrocardiogram, has emerged as a non-invasive measurement for quantifying the spatial inhomogeneity of ventricular repolarization under various conditions, including acute stress. Because burn injuries elicit acute stress reactions, it was hypothesized that QT dispersion increases with the severity of the burn injury. To test the hypothesis, 13 burned patients (age range of 22-76 years, nine males, ranging from 4.0 to 75.0% of total body surface area burned) in whom a measurable 12-lead electrocardiogram had been obtained within 4h after arrival at the emergency department were identified retrospectively, and their QTc intervals, i.e. QT intervals corrected for heart rate by the standard Bazett formula, were measured. QTc dispersion (QTcd) was then calculated, and correlations were assessed with burn severity (burn index, BI; prognostic burn index, PBI). Of the 13 patients, nine patients had a prolonged QTcd (>40 ms), and linear correlation analyses showed significant positive correlations between QTcd and both BI and PBI (r=0.61 and 0.62, respectively). In conclusion, QT dispersion was greater in the burned patients, and although the pathophysiology was unclear from the present study, the findings suggested that acute stress contributed to the spatial inhomogeneity of ventricular repolarization.
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Affiliation(s)
- Masaru Suzuki
- Department of Emergency and Critical Care Medicine, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
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Caron MF, Hotsko AL, Robertson S, Mandybur L, Kluger J, White CM. Electrocardiographic and hemodynamic effects of Panax ginseng. Ann Pharmacother 2002; 36:758-63. [PMID: 11978148 DOI: 10.1345/aph.1a411] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To determine whether Panax ginseng ingestion can acutely or chronically alter electrocardiographic parameters: PR, QRS, QT, QTc, and RR intervals, and QT and QTc interval dispersion. Effects of P. ginseng on blood pressure and heart rate also were evaluated. METHODS This is a prospective, randomized, double-blind, placebo-controlled study of healthy adults at the University of Connecticut. Thirty subjects were randomly allocated to receive 28 days of therapy with either P. ginseng extract 200 mg or placebo. Baseline 12-lead electrocardiograms (ECGs) were obtained. Subsequent ECGs were performed following study drug ingestion at 50 minutes, 2 hours, and 5 hours on days 1 and 28. Blood pressure readings were taken with each ECG. RESULTS P. ginseng ingestion increased the QTc interval by 0.015 seconds on day 1 at 2 hours compared with the placebo group (p = 0.03). It also reduced diastolic blood pressure from 75 +/- 5 mm Hg at baseline to 70 +/- 6 mm Hg at the same time point (p = 0.02). The observed effects are not believed to be clinically significant. No other statistically significant changes were found in electrocardiographic or hemodynamic variables on days 1 or 28. CONCLUSIONS P. ginseng, at doses of 200 mg of the extract daily, increases the QTc interval and decreases diastolic blood pressure 2 hours after ingestion in healthy adults on the first day of therapy.
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Affiliation(s)
- Michael F Caron
- School of Pharmacy, University of Connecticut, Storrs, CT, USA
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White CM, Grant EM, Quintiliani R. Moxifloxacin does increase the corrected QT interval. Clin Infect Dis 2001; 33:1441-4. [PMID: 11565091 DOI: 10.1086/323015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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