BACKGROUND Cardiac resynchronization therapy (CRT) improves hemodynamics and symptoms of heart failure by reducing ventricular dyssynchronity. Conversely, recent studies have demonstrated that right univentricular pacing in patients with an ejection fraction below 40% aggravates heart failure. In this retrospective study, we compared progression of disease in patients with mild to moderate hear...

Right ventricular apical pacing may cause or worsen mitral regurgitation (MR). Potential mechanisms for this adverse sequelae include intraventricular dyssynchrony, altered papillary muscle function, pacing-induced cardiomyopathy with left ventricular dilation, and annular dilation. In contrast, biventricular (BiV) pacing may improve MR presumably by opposing the negative effects. Whether or no...

The role of biventricular pacing is expanding beyond the New York Heart Association classes III and IV heart failure (HF) patient to include less symptomatic patients, earlier in the course of their disease process. This multisite pacing strategy has substantially altered the natural course of ventricular failure, exerting its physiological impact through favourable cardiac remodelling and impr...

BACKGROUND Biventricular (BiV) and left ventricular (LV) pacing similarly augment systolic function in left bundle-branch block (LBBB)-failing hearts despite different electrical activation. We tested whether electrical synchrony is required to achieve mechanical synchronization and functional benefit from pacing. METHODS AND RESULTS Epicardial mapping, tagged MRI, and hemodynamics were obtai...

Uses a structured format?Background:YesObjectives:YesSearch strategy:YesSelection criteria:YesData collection and analysis: YesMain results:Pooled results reportedReviewers’ conclusions:Reports results IntroductionDetailed introduction that includes description of health problem, current treatment options and a brief overview of CRT Me...

It is established that cardiac resynchronisation therapy (CRT) reduces mortality and hospitalisation and improves functional class in patients with NYHA class 3-4 heart failure, an ejection fraction of ≤ 35% and a QRS duration of ≥ 120ms. Recent updates in the American guidelines have expanded the demographic of patients in whom CRT may be appropriate. Here we present two cases of complex CRT; ...