Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota.
Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota.
J Am Coll Cardiol. 2019 Aug 6;74(5):645-655. doi: 10.1016/j.jacc.2019.05.053.
Conduction abnormalities including bundle branch block are recognized sequelae following septal myectomy in patients with hypertrophic cardiomyopathy, but their incidence and effect on long-term mortality have not been well studied.
This study was conducted to determine the impact of conduction abnormalities on mortality in patients with obstructive hypertrophic cardiomyopathy following myectomy.
The outcomes of 2,482 patients with obstructive hypertrophic cardiomyopathy who underwent transaortic septal myectomy from 1961 to 2016 were analyzed. Pre-operative and early post-operative electrocardiograms were reviewed to determine conduction status. The study endpoint was all-cause mortality.
Mean age at operation was 54.2 ± 14.6 years, and 1,370 patients (55.2%) were men. Pre-operatively, 2,159 patients (87.0%) had normal conduction, of whom 38.8% developed left bundle branch block, 1.1% developed right bundle branch block (RBBB), and 0.6% had complete heart block (CHB) after myectomy. Among 112 patients with baseline RBBB, 34.8% developed CHB post-operatively. Overall, only 2.3% of patients developed CHB. Over a median follow-up period of 8.6 years, overall mortality differed among post-operative conduction groups after adjustment for age, sex, and concomitant procedures (p = 0.015). Specifically, mortality in those with paced rhythm after myectomy was significantly increased relative to those with normal conduction (hazard ratio: 1.57; 95% confidence interval: 1.15 to 2.14; p = 0.005), although no significant difference was observed in left bundle branch block and RBBB (vs. normal) groups.
Left bundle branch block is a common sequela after septal myectomy but does not influence post-operative mortality. Myectomy-related CHB is rare in patients with baseline normal conduction, while pre-existing RBBB greatly increases the risk for CHB. Persistent paced rhythm after operation is an independent predictor of mortality.
传导异常，包括束支传导阻滞，是肥厚型心肌病患者行间隔心肌切除术（septal myectomy）后的常见后遗症，但它们的发生率及其对长期死亡率的影响尚未得到很好的研究。
本研究旨在确定传导异常对行间隔心肌切除术的梗阻性肥厚型心肌病患者死亡率的影响。
分析了 1961 年至 2016 年间接受经主动脉间隔心肌切除术的 2482 例梗阻性肥厚型心肌病患者的结果。回顾术前和术后早期的心电图以确定传导状态。研究终点为全因死亡率。
手术时的平均年龄为 54.2±14.6 岁，1370 例（55.2%）为男性。术前 2159 例（87.0%）患者传导正常，其中 38.8%出现左束支传导阻滞，1.1%出现右束支传导阻滞（RBBB），0.6%发生完全性心脏传导阻滞（CHB）。在 112 例基线 RBBB 的患者中，34.8%术后发生 CHB。总的来说，只有 2.3%的患者发生 CHB。在中位随访 8.6 年后，校正年龄、性别和伴随手术程序后，各组术后传导差异对总死亡率有影响（p=0.015）。具体来说，与传导正常患者相比，术后起搏节律患者的死亡率显著增加（风险比：1.57；95%置信区间：1.15 至 2.14；p=0.005），尽管左束支传导阻滞和 RBBB 组（与正常组相比）无显著差异。
左束支传导阻滞是间隔心肌切除术后常见的后遗症，但不影响术后死亡率。在基线传导正常的患者中，与手术相关的 CHB 很少见，而基线存在的 RBBB 大大增加了 CHB 的风险。术后持续起搏节律是死亡率的独立预测因素。
