Objective. The aim of our study was to evaluate the effect of cardiac resyncronization
therapy (CRT) on QT dispersion (QTd), JT dispersion (JTd) and transmural dispersion of repolarization
(TDR), markers of heterogeneity of ventricular repolarization in a study population
with severe heart failure.
Methods and Results. Fifty patients (43 male, 7 female, aged 60.2 ± 3.1 years) suffering from congestive heart failure (N = 39 NYHA class III; N = 11 NYHA class IV) as a result of coronary artery disease (N = 19) or of dilated cardiomyopathy (N = 31), sinus rhythm, QRS duration >130 ms (mean QRS duration >156 ± 21 ms), an ejection fraction < 35%, left ventricular end-diastolic diameter >55 mm, underwent permanent biventricular DDDR pacemaker implantation. A 12-lead standard electrocardiogram was performed at baseline, during right-, left-, and biventricular pacing and QTd, JTd and TDR were assessed. Biventricular pacing significantly reduced QTd (73.93 ± 19.4 ms during BiVP vs 91 ± 6.7 ms at sinus rhythm, p = 0.004), JTd (73.18 ± 17.16 ms during BiVP vs 100.72 ± 39.04 at baseline p = 0.003), TDR (93.16 ± 15.60 vs 101.55 ± 19.08 at baseline; p<0.004), as compared to sinus rhythm. Right ventricular endocardial pacing and left ventricular epicardial pacing both enhanced QTd (RVendoP 94 ± 51 ms, p<0.03; LVepiP 116 ± 71 ms, p<0.02) and TDR (RVendoP 108.13 ± 19.94 ms; p<0.002; LVepiP 114.71 ± 26.1; p<0.05).There was no effect on JTd during right and left ventricular stimulation.
Conclusions. Biventricular pacing causes a statistically significant reduction of ventricular heterogeneity of ripolarization and has an electrophysiological antiarrhythmic influence on arrhythmogenic substrate of dilatative cardiomiopathy. (Heart International 2006; 2: 27-32)
Biventricular pacing, QT dispersion, JT dispersion, TDR, Heart failure
Vincenzo Russo, MD, Via della Resistenza, 48, 80021 Afragola (NA) – Italy, email@example.com
Share this Article
Related Content In Heart Failure
Explaining Sex Differences in Cardiac Resynchronisation Therapy Outcome
European Journal of Arrhythmia & Electrophysiology. 2020;6(1):17-23 DOI: https://doi.org/10.17925/EJAE.2020.6.1.17
Over the past years, several reports have drawn attention to the need to consider sex-specific differences in cardiac resynchronisation therapy (CRT). Most importantly, there is growing concern on the underrepresentation of women in CRT landmark trials which laid the foundation for present guidelines. Patients with symptomatic heart failure, reduced left ventricular ejection fraction (LVEF) ≤35% […]
Quantification of Seasonal Variation in Daily Physical Activity in Individuals with Heart Failure and Implantable Cardioverter Defibrillator/Cardiac Resynchronisation Therapy Devices
Heart International. 2019;13(2):31–7
In individuals with heart failure (HF) who also have implanted cardioverter defibrillators and/or cardiac resynchronisation therapy (ICD/CRT) devices, low daily physical activity (PA) levels lead to increased risk of mortality, poor aerobic capacity and lower health-related quality of life.1 Improving daily PA in these individuals may, therefore, be an important clinical endpoint; however, designing interventional […]
Normalised Heart Rate Variability After Sacubitril/Valsartan
European Journal of Arrhythmia & Electrophysiology. 2019;5(1):60-1 DOI: https://doi.org/10.17925/EJAE.2019.5.1.60
We report the case of a 44-year-old woman with a history of chronic heart failure with reduced ejection fraction (HFrEF) due to ischemic cardiomyopathy (New York Heart Association [NYHA] class II). In 2010, she had a myocardial infarction with thrombotic occlusion of the left anterior descending coronary artery, alleged in the context of an essential thrombocythaemia. […]
Journal articles and more to your inbox
Get the latest clinical insights from touchCARDIOSign me up!