Faculdade de Medicina, Heart Institute (InCor), Hospital das Clínicas, Universidade de São Paulo, São Paulo, SP, Brazil.
Clinics (Sao Paulo). 2013 Jul;68(7):986-91. doi: 10.6061/clinics/2013(07)16.
Few studies have evaluated cardiac electrical activation dynamics after cardiac resynchronization therapy. Although this procedure reduces morbidity and mortality in heart failure patients, many approaches attempting to identify the responders have shown that 30% of patients do not attain clinical or functional improvement. This study sought to quantify and characterize the effect of resynchronization therapy on the ventricular electrical activation of patients using body surface potential mapping, a noninvasive tool.
This retrospective study included 91 resynchronization patients with a mean age of 61 years, left ventricle ejection fraction of 28%, mean QRS duration of 182 ms, and functional class III/IV (78%/22%); the patients underwent 87-lead body surface mapping with the resynchronization device on and off. Thirty-six patients were excluded. Body surface isochronal maps produced 87 maximal/mean global ventricular activation times with three regions identified. The regional activation times for right and left ventricles and their inter-regional right-to-left ventricle gradients were calculated from these results and analyzed. The Mann-Whitney U-test and Kruskall-Wallis test were used for comparisons, with the level of significance set at p≤0.05.
During intrinsic rhythms, regional ventricular activation times were significantly different (54.5 ms vs. 95.9 ms in the right and left ventricle regions, respectively). Regarding cardiac resynchronization, the maximal global value was significantly reduced (138 ms to 131 ms), and a downward variation of 19.4% in regional-left and an upward variation of 44.8% in regional-right ventricular activation times resulted in a significantly reduced inter-regional gradient (43.8 ms to 17 ms).
Body surface potential mapping in resynchronization patients yielded electrical ventricular activation times for two cardiac regions with significantly decreased global and regional-left values but significantly increased regional-right values, thus showing an attenuated inter-regional gradient after the cardiac resynchronization therapy.
很少有研究评估心脏再同步治疗后的心脏电激动动力学。尽管该手术降低了心力衰竭患者的发病率和死亡率，但许多试图确定应答者的方法表明，30%的患者并未获得临床或功能改善。本研究旨在使用体表电位标测技术（一种非侵入性工具）量化和描述心脏再同步治疗对患者心室电激动的影响。
本回顾性研究纳入了 91 例再同步治疗患者，平均年龄 61 岁，左心室射血分数 28%，平均 QRS 时限 182ms，心功能分级 III/IV 级（78%/22%）；患者在启用和停用再同步设备时进行了 87 导联体表标测。排除了 36 例患者。体表等时图产生了 87 个最大/平均全局心室激活时间，并确定了 3 个区域。从这些结果计算并分析了右心室和左心室的区域激活时间及其区域间右至左心室梯度。使用 Mann-Whitney U 检验和 Kruskal-Wallis 检验进行比较，显著性水平设置为 p≤0.05。
在固有节律时，区域心室激活时间差异显著（右心室和左心室区域分别为 54.5ms 和 95.9ms）。关于心脏再同步，最大全局值显著降低（从 138ms 降至 131ms），区域左心室激活时间下降 19.4%，区域右心室激活时间上升 44.8%，导致区域间梯度显著降低（从 43.8ms 降至 17ms）。
再同步患者的体表电位标测产生了两个心脏区域的心室电激动时间，全局和区域左心室值显著降低，但区域右心室值显著升高，因此显示心脏再同步治疗后区域间梯度减弱。
