Cardiovascular Center, Division of Cardiology, Department of Internal Medicine, College of Medicine, Eulji University Hospital, Eulji University of Korea, Daejeon, Korea.
Cardiovascular Center, Division of Cardiology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea.
Echocardiography. 2021 Feb;38(2):175-182. doi: 10.1111/echo.14942. Epub 2021 Jan 6.
Long-term right ventricular pacing is the only treatment for patients with a complete atrioventricular block (CAVB); however, it frequently triggers ventricular dys-synchrony with left ventricular (LV) dysfunction. Previous studies showed that an early decline of LV global longitudinal strain (GLS) predicts pacing-induced LV dysfunction. We aimed to investigate the potential ability of the initial LV strain to predict pacing-induced cardiomyopathy (PICM) through long-term follow-ups.
We retrospectively enrolled 80 patients with CAVB with normal LV function who were implanted with dual-chamber pacemakers between 2008 and 2018. Echocardiographic data and parameters (including longitudinal, radial, and circumferential strain based on speckle-tracking) were analyzed for the pre-implant (≤6 months) and post-implant periods. PICM was defined as a ≥10% reduction in the left ventricular ejection fraction (LVEF) resulting in an LVEF of <50% during the post-implant period. Predictors of PICM were identified using Cox proportional hazard models.
Patients who developed PICM were more likely to exhibit lower baseline LV GLS, as well as wider native and pacing QRS durations, than those who did not develop PICM (P = .016, P = .011, and P = .026, respectively). In the multivariate analysis, pre-implant LV GLS (hazard ratio: 1.27; 95% confidence interval 1.009-1.492; P = .004) was independently associated with the development of PICM.
A lower baseline LV GLS predicts an increased risk of PICM. Patients with CAVB exhibiting low GLS are at increased risk of PICM. More frequent follow-up visits are warranted in these patients, who may also require de novo His-bundle pacing or an upgrade to biventricular pacing.
永久性右心室起搏是治疗完全性房室传导阻滞（CAVB）患者的唯一方法，但它常引发左心室（LV）功能障碍的心室不同步。先前的研究表明，LV 整体纵向应变（GLS）的早期下降可预测起搏诱导的 LV 功能障碍。我们旨在通过长期随访来研究初始 LV 应变预测起搏诱导性心肌病（PICM）的潜在能力。
我们回顾性纳入了 2008 年至 2018 年间植入双腔起搏器的 80 例 CAVB 伴正常 LV 功能患者。分析了超声心动图数据和参数（包括斑点追踪的纵向、径向和环向应变）在植入前（≤6 个月）和植入后时期的变化。起搏诱导性心肌病定义为植入后左心室射血分数（LVEF）下降≥10%，导致 LVEF<50%。采用 Cox 比例风险模型识别 PICM 的预测因素。
与未发生 PICM 的患者相比，发生 PICM 的患者基线时 LV GLS 更低，固有和起搏 QRS 持续时间更宽（P=0.016，P=0.011 和 P=0.026）。多变量分析显示，植入前 LV GLS（风险比：1.27；95%置信区间 1.009-1.492；P=0.004）与 PICM 的发生独立相关。
基线 LV GLS 降低预示着 PICM 的风险增加。CAVB 患者 LGS 降低者发生 PICM 的风险增加。这些患者需要更频繁的随访，他们可能还需要新的希氏束起搏或升级为双心室起搏。
