Jeewa Aamir, Pitfield Alexander F, Potts James E, Soulikias Wendy, DeSouza Eustace S, Hollinger A J, Sandor George G S, LeBlanc Jacques G, Campbell Andrew M, Sanatani Shubhayan
Division of Cardiology, Department of Pediatrics, British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC, Canada.
Pediatr Cardiol. 2010 Feb;31(2):181-7. doi: 10.1007/s00246-009-9581-4.
Biventricular (BiV) pacing or cardiac resynchronization therapy (CRT) is an established therapy for heart failure in adults. In children, cardiac dyssynchrony occurs most commonly following repair of congenital heart disease (CHD) where multisite pacing has been shown to improve both hemodynamics and ventricular function. Determining which patient types would specifically benefit has not yet been established. A prospective, repeated measures design was undertaken to evaluate BiV pacing in a cohort of children undergoing biventricular repair for correction of their CHD. Hemodynamics, arterial blood gas, electrocardiographic (ECG), and echocardiographic data were collected. Pacing protocol was undertaken prior to the patient's extubation with 20 min of conventional right ventricular (RV) or BiV pacing, preceded and followed by 10 min of recovery time. Multivariate statistics were used to analyze the data with p values <0.05 considered significant. Twenty-five (14 female) patients underwent surgery at a median (range) age of 5.2 (0.1-37.4) months with no early mortality. The Risk-adjusted classification for Congenital Heart Surgery (RACHS) scores were 2 in 14 patients, 3 in eight patients, and 4 in three patients. None had pre-existing arrhythmias, dyssynchrony, or required pacing pre-operatively. No patient required implantation of a permanent pacemaker post-operatively. The median cardio-pulmonary bypass time was 96 (55-236) min. RV and BiV pacing did not improve cardiac index from baseline (3.23 vs. 3.42 vs. 3.39 L/min/m2; p > 0.05). The QRS duration was not changed with pacing (100 vs. 80 vs. 80 ms; p > 0.05). On echocardiography, the time-to-peak velocity difference between the septal and posterior walls (synchrony) during pacing was similar to baseline and was also not statistically significant. BiV pacing did not improve cardiac output when compared to intrinsic sinus rhythm or RV pacing in this cohort of patients. Our study has shown that BiV pacing is not indicated in children who have undergone routine BiV congenital heart surgery. Further prospective studies are needed to assess the role of multisite pacing in children with ventricular dyssynchrony such as those with single ventricles, those undergoing reoperation or those with high RACHS scores.
双心室（BiV）起搏或心脏再同步治疗（CRT）是治疗成人心力衰竭的既定疗法。在儿童中，心脏不同步最常见于先天性心脏病（CHD）修复术后，多部位起搏已被证明可改善血流动力学和心室功能。确定哪些患者类型会特别受益尚未明确。我们采用前瞻性重复测量设计，对一组接受双心室修复以纠正CHD的儿童进行BiV起搏评估。收集了血流动力学、动脉血气、心电图（ECG）和超声心动图数据。在患者拔管前进行起搏方案，先进行20分钟的传统右心室（RV）或BiV起搏，前后各有10分钟的恢复时间。使用多变量统计分析数据，p值<0.05被认为具有统计学意义。25名（14名女性）患者接受了手术，中位（范围）年龄为5.2（0.1 - 37.4）个月，无早期死亡病例。先天性心脏病手术风险调整分类（RACHS）评分，14例患者为2分，8例患者为3分，3例患者为4分。术前均无心律失常、不同步或需要起搏的情况。术后无患者需要植入永久性起搏器。中位体外循环时间为96（55 - 236）分钟。RV和BiV起搏均未使心脏指数较基线水平提高（分别为3.23 vs. 3.42 vs. 3.39 L/min/m²；p>0.05）。起搏时QRS波时限未改变（分别为100 vs. 80 vs. 80 ms；p>0.05）。超声心动图显示，起搏期间室间隔与后壁之间的峰值速度差时间（同步性）与基线相似，也无统计学意义。在该组患者中，与固有窦性心律或RV起搏相比，BiV起搏并未改善心输出量。我们的研究表明，常规双心室先天性心脏病手术后的儿童不适合BiV起搏。需要进一步的前瞻性研究来评估多部位起搏在心室不同步儿童中的作用，如单心室患儿、再次手术患儿或RACHS评分高的患儿。
