Pujol-López Margarida, Graterol Freddy R, Borràs Roger, Garcia-Ribas Cora, Guichard J Baptiste, Regany-Closa Mariona, Jiménez-Arjona Rafael, Niebla Mireia, Poza Marina, Carro Esther, Castel M Ángeles, Arbelo Elena, Porta-Sánchez Andreu, Sitges Marta, Roca-Luque Ivo, Doltra Adelina, Guasch Eduard, Tolosana José M, Mont Lluís
Institut Clínic Cardiovascular (ICCV), Hospital Clínic, Universitat de Barcelona, Catalonia, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain.
Institut Clínic Cardiovascular (ICCV), Hospital Clínic, Universitat de Barcelona, Catalonia, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain.
JACC Clin Electrophysiol. 2025 May 1. doi: 10.1016/j.jacep.2025.03.024.
Randomized studies comparing conduction system pacing (CSP) with biventricular pacing (BiVP) are scarce and do not include clinical outcomes.
The CONSYST-CRT (Conduction System Pacing vs Biventricular Resynchronization Therapy in Systolic Dysfunction and Wide QRS) trial aimed to test the noninferiority of CSP as compared with BiVP in patients with an indication for cardiac resynchronization therapy, with respect to a combined clinical endpoint at 1-year follow-up.
CONSYST-CRT is a randomized, controlled, noninferiority trial (NCT05187611). One hundred thirty-four patients with cardiac resynchronization therapy indication were randomized to BiVP or CSP and followed up for 12 months. Crossover was allowed when the primary allocation procedure failed. The atrioventricular interval was optimized to obtain fusion with intrinsic conduction. The primary combined endpoint was all-cause mortality, cardiac transplant, heart failure hospitalization, or left ventricular ejection fraction (LVEF) improvement <5 points at 12 months. Secondary endpoints were LVEF increase, LV end-systolic volume (LVESV) decrease, echocardiographic response (≥15% LVESV decrease), QRS shortening, septal flash correction, NYHA functional class improvement, and a combined endpoint of all-cause mortality, cardiac transplantation, and heart failure hospitalization.
Sixty-seven patients were allocated to each group. Eighteen patients (26.9%) crossed from CSP to BiVP; 5 (7.5%) crossed over from BiVP to CSP. Noninferiority (NI) was observed for CSP compared with BiVP for the primary endpoint (23.9% vs 29.8%, respectively; mean difference -5.9; 95% CI: -21.1 to 9.2; P = 0.02) and for the combined endpoint of all-cause mortality, cardiac transplantation, and heart failure hospitalization (11.9% vs 17.9%; P < 0.01 NI); echocardiographic response (66.6% vs 59.7%; P = 0.03 NI); NYHA functional class (P < 0.001 NI); and QRS shortening (P < 0.01). LVEF, LVESV, and septal flash endpoint values were similar, but noninferiority was not met (14.1 ± 10% vs 14.4 ± 10%, -27.9 ± 27% vs -27.9 ± 28%, -2.2 ± 2.7 mm vs -2.7 ± 2.4 mm, respectively).
CSP was noninferior to BiVP in achieving clinical and echocardiographic response, suggesting that CSP could be an alternative to BiVP. (Conduction System Pacing vs Biventricular Resynchronization Therapy in Systolic Dysfunction and Wide QRS [CONSYST-CRT]; NCT05187611).
比较传导系统起搏（CSP）与双心室起搏（BiVP）的随机研究较少，且未纳入临床结局。
CONSYST-CRT（收缩功能障碍和宽QRS波患者的传导系统起搏与双心室再同步治疗）试验旨在测试在心脏再同步治疗适应证患者中，与BiVP相比，CSP在1年随访时的联合临床终点方面是否不劣于BiVP。
CONSYST-CRT是一项随机、对照、非劣效性试验（NCT05187611）。134例有心脏再同步治疗适应证的患者被随机分配至BiVP或CSP组，并随访12个月。当主要分配程序失败时允许交叉。优化房室间期以实现与固有传导的融合。主要联合终点为12个月时的全因死亡率、心脏移植、心力衰竭住院或左心室射血分数（LVEF）改善<5个百分点。次要终点为LVEF增加、左心室收缩末期容积（LVESV）减少、超声心动图反应（LVESV减少≥15%）、QRS波缩短、室间隔闪烁校正、纽约心脏协会（NYHA）功能分级改善，以及全因死亡率、心脏移植和心力衰竭住院的联合终点。
每组分配67例患者。18例患者（26.9%）从CSP交叉至BiVP；5例（7.5%）从BiVP交叉至CSP。与BiVP相比，CSP在主要终点方面被观察到非劣效性（分别为23.9%和29.8%；平均差异-5.9；95%置信区间：-21.1至9.2；P=0.02），在全因死亡率、心脏移植和心力衰竭住院的联合终点方面也被观察到非劣效性（11.9%对17.9%；P＜非劣效性0.01）；超声心动图反应（66.6%对59.7%；P=0.03非劣效性）；NYHA功能分级（P＜非劣效性0.001）；以及QRS波缩短（P＜0.01）。LVEF、LVESV和室间隔闪烁终点值相似，但未达到非劣效性（分别为14.1±10%对14.4±10%，-27.9±27%对-27.9±28%，-2.2±2.7mm对-2.7±2.4mm）。
在实现临床和超声心动图反应方面，CSP不劣于BiVP，表明CSP可能是BiVP的替代方案。（收缩功能障碍和宽QRS波患者的传导系统起搏与双心室再同步治疗[CONSYST-CRT]；NCT05187611）
