Efficacy, Safety, and Performance of Isolated Left vs. Right Ventricular Pacing in Patients with Bradyarrhythmias: A Randomized Controlled Trial

Abstract

Background Considering the potential deleterious effects of right ventricular (RV) pacing, the hypothesis of this study is that isolated left ventricular (LV) pacing through the coronary sinus is safe and may provide better clinical and echocardiographic benefits to patients with bradyarrhythmias and normal ventricular function requiring heart rate correction alone. Objective To assess the safety, efficacy, and effects of LV pacing using an active-fixation coronary sinus lead in comparison with RV pacing, in patients eligible for conventional pacemaker (PM) implantation. Methods Randomized, controlled, and single-blinded clinical trial in adult patients submitted to PM implantation due to bradyarrhythmias and systolic ventricular function ≥ 0.40. Randomization (RV vs. LV) occurred before PM implantation. The main results of the study were procedural success, safety, and efficacy. Secondary results were clinical and echocardiographic changes. Chi-squared test, Fisher's exact test and Student's t-test were used, considering a significance level of 5%. Results From June 2012 to January 2014, 91 patients were included, 36 in the RV Group and 55 in the LV Group. Baseline characteristics of patients in both groups were similar. PM implantation was performed successfully and without any complications in all patients in the RV group. Of the 55 patients initially allocated into the LV group, active-fixation coronary sinus lead implantation was not possible in 20 (36.4%) patients. The most frequent complication was phrenic nerve stimulation, detected in 9 (25.7%) patients in the LV group. During the follow-up period, there were no hospitalizations due to heart failure. Reductions of more than 10% in left ventricular ejection fraction were observed in 23.5% of patients in the RV group and 20.6% of those in the LV group (p = 0.767). Tissue Doppler analysis showed that 91.2% of subjects in the RV group and 68.8% of those in the LV group had interventricular dyssynchrony (p = 0.022). Conclusion The procedural success rate of LV implant was low, and the safety of the procedure was influenced mainly by the high rate of phrenic nerve stimulation in the postoperative period.

Cardiomyopathy Associated with Right Ventricular Apical Pacing-Systematic Review and Meta-Analysis

“…After the exclusion of duplicates and non-relevant studies, 36 studies were retrieved for further full-text evaluation by reviewing study titles and abstracts. We further excluded three studies that were projected in cross-over manner [ 4 , 5 , 6 ], six trials that did not evaluate LVEF in the follow-up [ 7 , 8 , 9 , 10 , 11 , 12 ], seven studies in which information about RVAP was absent or RVAP was <20% [ 13 , 14 , 15 , 16 , 17 , 18 , 19 ], three studies in which patients were treated according to the ‘’ablate and pace” method [ 20 , 21 , 22 ], one trial with a short-term follow-up [ 23 ], one trial which was a prolonged follow-up of the so far included study, and one study because of statistical issues [ 24 ]. Finally, fourteen randomized controlled studies published in the period of 2008–2017 were included in this systematic review and meta-analysis.…”

“…A similar result was reported by Crevelari; in her research, no hospitalization due to heart failure was observed. However, 23.5% of patients with RVP had over 10% LVEF reduction at the end of the follow-up [ 7 ]. According to the three meta-analyses, right ventricular non-apical electrode location ensures less harmful influence on LVEF in comparison with its apical location [ 45 , 46 , 47 ].…”

Comparative evaluation of permanent cardiac pacing modes in patients with arrhythmic variant of coronary artery disease (bradyarrhythmia)

“…(2019) предлагают для пациентов с брадиаритмиями и нормальной функцией желудочков, нуждающейся только в коррекции частоты сердечных сокращений, проводить изолированную ЭКС ЛЖ через коронарный синус, которая обеспечивает лучшие клинические и ЭхоКГ результаты. Проведение тканевого допплерографического анализа показало, что межжелудочковая диссинхрония в группе пациентов со стимуляцией ЛЖ наблюдалась реже на 22,4%, по сравнению с таковой у пациентов со стимуляцией ПЖ [11].…”

Estimulação do Ramo Esquerdo: A Estimulação Cardíaca Mudou para Sempre?

“…Despite the great benefit of the AV synchronized pacing, the endocardial lead at the apex of the right ventricle remained causing unwanted pacing 4 with wide QRS and complete left bundle branch block effect, with significant dyssynchrony of the left ventricular walls given rise to a second problem: the "Ventricular Pacemaker Syndrome or Wide QRS Syndrome", 7 whose prevention and treatment gave origin to resynchronization therapy. [5][6][7][8] . Despite being present in the entire cardiac stimulation, this dyssynchrony was neglected for a long time due to the great benefit resulting of the bradycardia correction.…”