Active clinical trials for "Bundle-Branch Block"

The present study will recruit 50 symptomatic non-ischemic cardiomyopathy (NICM) patients with left ventricular ejection fraction (LVEF) below 35% and complete left bundle branch block (CLBBB), who have not received complete guideline-directed medical therapy (GDMT). Each patient was randomized to 2 groups, GDMT or left bundle branch pacing combined with GDMT (LBBP+GDMT) as initial therapy and was followed up for 2 phases: 0-6 months (phase I), 7-18 months (phase II). The primary objective is to compare the LVEF change , syncope and malignant ventricular arrhythmias between GDMT group and LBBP+GDMT group, and to observe which strategy will significantly reduce the percentage of recommendations for an implantable cardioverter-defibrillator (ICD) during phase I study. The second outcome measures including health economics, echocardiography parameters[left ventricular ejection fraction (LVEF), left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV)], N-terminal pro B-type natriuretic peptide (NT-proBNP) level, New York Heart Association (NYHA) class, 6-minute walking distance (6MWD), quality of life score(QOL) and incidence of clinical adverse events.

The purpose of this study is to evaluate the effect of conduction system pacing versus biventricular pacing on death, worsening heart failure, and left ventricular ejection fraction in patients with chronic heart failure with reduced ejection fraction and left bundle branch block.

Chagas disease is an endemic problem in Latin America, where millions of people are chronically infected with T. cruzi. Recently, it was assumed to have clinical and epidemiological relevance in several other countries due to migratory and globalizing social factors. CCC occurs in 30-50% of infected individuals, causing considerable morbidity/mortality rates. Heart failure is the most prevalent morbidity. While CRT and drug treatment have been advocated and implemented without much success to improve the clinical condition of patients with CCC, there is no consistent scientific evidence on the role of cardiac contractility modulation (CCM) as a form of adjuvant treatment for heart failure in patients with CCC. The hypothesis of this study is that patients with CCC, advanced heart failure, severe systolic dysfunction, and non-LBB have better clinical and functional responses when undergoing implantation of a CCM device than when undergoing cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) via biventricular (BiV) pacing significantly reduces morbidity and mortality in patients with left bundle branch block (LBBB), impaired LV function and heart failure in spite of optimal medical treatment. CRT positive effects are based on the existence of an electromechanical dyssynchrony induced by the abnormal activation sequence associated with the presence of a left bundle branch block (LBBB), which is thought to be responsible for a negative LV remodeling leading to LVEF impairment and heart failure progression. However, one third of patients undergoing CRT are considered non responders due to different reasons. Recently, left bundle branch area pacing (LBBAP) has emerged as a novel physiological pacing modality aiming for conduction system recruitment in patients with normal or impaired atrioventricular conduction, including patients with LBBB. LBBAP achieves LBBB correction in up to 85% of the cases and thus could be a promising pacing modality for CRT candidates.

The investigators aim to prospectively evaluate the efficacy and mechanism of benefit of His-bundle pacing enhanced cardiac resynchronization therapy (His-CRT) vs. cardiac resynchronization therapy (BIV-CRT) in patients with heart failure and right bundle branch block (RBBB).

This is a prospective, single-arm, non-randomized, non-blinded study designed to characterize the locations of His Bundle (HB) pacing that results in correction of electrical dyssynchrony and to characterize morphology and activation time of local intracardiac electrogram (IEGM) with an electro-anatomical mapping system during a device implant procedure and secondarily to assess the efficacy of HB pacing or HB plus LV pacing (when indicated) in correction of electrical dyssynchrony in heart failure patients with left bundle branch block.

The primary hypothesis of the proposed study is that an electrophysiology-based algorithmic approach is superior to standard clinical follow-up with 30-day monitoring in reducing the combined endpoint of syncope, hospitalization, and death in patients in patients with new of left bundle branch block following transcatheter aortic valve implantation (TAVI).

Heart failure is a leading cause of morbidity and mortality. Cardiac resynchronization therapy (CRT) is a well-established treatment for patients with symptomatic heart failure in spite of optimised medical treatment (OMT), reduced left ventricular pump function with left ventricular ejection fraction (LVEF) ≤ 35% and prolonged activation of the ventricles (bundle branch block: BBB). CRT is established by implanting an advanced pacemaker system with three leads in the right atrium, right ventricle, and in the coronary sinus (CS) for pacing the left ventricle (LV), and often is combined with an implantable defibrillator (ICD) function. On average, CRT treatment improves longevity, quality of life and functional class, and reduces heart failure symptoms. Thus, at present, CRT is indicated for heart failure patients on OMT with BBB or chronic right ventricular (RV) pacing. It is, however, a significant problem that 30-40% of CRT patients do not benefit measurably - showing symptomatic improvement or improved cardiac pump function - from this therapy (socalled non-responders). LV lead placement is one of the major determinants of beneficial effect from CRT. Observational studies and three randomised trials with small sample sizes indicate that targeted placement of the LV lead towards a late activated segment of the LV may be associated with improved outcome. Based on this literature, some physicians already search for late activation when positioning the LV lead. However, such a strategy was never tested in a controlled trial with a sample size sufficient to investigate important clinical outcomes. Detailed mapping for a late activation may increase operating times and infection risk, result in use of more electrodes and wires, thereby increasing costs, and increase radiation exposure for patient and staff. Placement of the LV lead in late activated areas close to myocardial scar may even result in higher risk of arrhythmia and death. At present, it is completely unsettled whether targeted positioning of the LV lead to the latest electrically activated area of LV is superior to contemporary standard CRT with regard to improving prognosis for patients with heart failure and BBB. The present study aims to test whether targeting the placement of the LV lead towards the latest electrically activated segment in the coronary sinus branches improves outcome as compared with standard LV lead implant in a patient population with heart failure and CRT indication.

Cardiac resynchronization therapy (CRT) with biventricular pacing (BiV) is the cornerstone treatment for heart failure patients with ventricular dyssynchrony. Recently, a new concept, conduction system pacing (CSP) with permanent pacing, including His bundle pacing and left bundle branch pacing, has been proposed as a potential alternative to conventional BiV-CRT. The prospective, randomized trial will compare echocardiographic, electrocardiographic, and clinical effects of CSP versus conventional BiV pacing in heart failure patients with reduced ejection fraction (LVEF ≤ 35%), sinus rhythm, and left bundle branch block. Patients will be randomized to either CSP or biventricular pacing study group and followed up for at least 6 months. The study will explore whether CSP is non-inferior to BiV pacing in echocardiographic, electrocardiographic, and clinical outcomes.

The study will investigate the feasibility of using direct HIS pacing or left bundle branch pacing (LBB pacing) as an alternative to biventricular pacing in patients with symptomatic heart failure and an ECG with a typical left bundle branch block pattern.