BACKGROUND This study aimed to compare the incidence and prognostic implications of new-onset conduction disturbances after surgical aortic valve replacement (SAVR) in patients with bicuspid aortic valve (BAV) aortic stenosis (AS) versus patients with tricuspid aortic valve (TAV) AS (ie, BAV-AS and TAV-AS, respectively). Additionally, the study included stratification of BAV patients according to subtype. METHODS In this cohort study, the incidence of postoperative third-degree atrioventricular (AV) block with subsequent permanent pacemaker requirement and new-onset left bundle-branch block (LBBB) was investigated in 1147 consecutive patients without preoperative conduction disorder who underwent isolated SAVR (with or without ascending aortic surgery) between January 1, 2005, and December 31, 2022. The groups were stratified by aortic valve morphology (BAV, n=589; TAV, n=558). The outcomes of interests were new-onset third-degree AV block or new-onset LBBB during the index hospitalization. The impact of new-onset postoperative conduction disturbances on survival was investigated in BAV-AS and TAV-AS patients during a median follow-up of 8.2 years. BAV morphology was further categorized according to the Sievers and Schmidtke classification system (possible in 307 BAV-AS patients) to explore association between BAV subtypes and new-onset conduction disturbances after SAVR. RESULTS The overall incidence of third-degree AV block and new-onset LBBB after SAVR was 4.5% and 7.8%, respectively. BAV-AS patients had a higher incidence of both new-onset third-degree AV block (6.5% versus 2.5%; P=0.001) and new-onset LBBB (9.7% versus 5.7%; P=0.013) compared with TAV-AS patients. New-onset LBBB was associated with an increased all-cause mortality during follow-up (adjusted hazard ratio, 1.60 [95% CI, 1.12-2.30]; P=0.011), whereas new-onset third-degree AV block was not associated with worse prognosis. Subgroup analysis of the BAV cohort revealed that BAV-AS patients with fusion of the right- and non-coronary cusps had the highest risk of new-onset third-degree AV block (adjusted odds ratio [aOR], 8.33 [95% CI, 3.31-20.97]; P<0.001, with TAV as reference group) and new-onset LBBB (aOR, 4.03 [95% CI, 1.84-8.82]; P<0.001, with TAV as reference group), whereas no significant association was observed for the other BAV subtypes. CONCLUSIONS New-onset LBBB after SAVR is associated with increased all-cause mortality during follow-up, and is more frequent complication in BAV AS patients compared with TAV-AS patients. BAV-AS patients with fusion of the right- and non-coronary cusps have an increased risk for conduction disturbances after SAVR. This should be taken into consideration when managing these patients.

中文翻译：

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二尖瓣和三尖瓣主动脉瓣狭窄患者外科主动脉瓣置换术后的传导障碍和结局。


背景 本研究旨在比较二叶式主动脉瓣 （BAV） 主动脉瓣狭窄 （AS） 患者与三尖瓣主动脉瓣 （TAV） AS 患者 （即 BAV-AS 和 TAV-AS） 手术后新发传导障碍的发生率和预后影响。此外，该研究还包括根据亚型对 BAV 患者进行分层。方法 在这项队列研究中，调查了 2005 年 1 月 1 日至 2022 年 12 月 31 日期间接受孤立性 SAVR （伴或不伴升主动脉手术） 的 1147 例连续无术前传导障碍患者术后三度房室传导阻滞伴随后需要永久起搏器和新发左束支传导阻滞 （LBBB） 的发生率。各组按主动脉瓣形态 （BAV， n=589;TAV，n=558）。感兴趣的结局是指数住院期间新发的 3 度 AV 传导阻滞或新发 LBBB。在中位随访 8.2 年期间，调查了 BAV-AS 和 TAV-AS 患者新发术后传导障碍对生存率的影响。根据 Sievers 和 Schmidtke 分类系统 （可能在 307 例 BAV-AS 患者中） 进一步对 BAV 形态进行分类，以探讨 BAV 亚型与 SAVR 后新发传导障碍之间的关联。结果 SAVR 后 3 度房室传导阻滞和新发 LBBB 的总发生率分别为 4.5% 和 7.8%。BAV-AS 患者新发 3 度房室传导阻滞的发生率较高 （6.5% vs 2.5%;P = 0.001） 和新发 LBBB （9.7% 对 5.7%;P=0.013） 与 TAV-AS 患者相比。 新发 LBBB 与随访期间全因死亡率增加相关 （校正风险比，1.60 [95% CI，1.12-2.30];P = 0.011），而新发的 3 度房室传导阻滞与较差的 预测无关。BAV 队列的亚组分析显示，右冠状动脉瓣和非冠状动脉瓣融合的 BAV-AS 患者新发 3 度房室传导阻滞的风险最高（校正比值比 [aOR]，8.33 [95% CI，3.31-20.97];P<0.001，TAV 为参考组）和新发 LBBB （aOR，4.03 [95% CI，1.84-8.82];P<0.001，以 TAV 为参考组），而其他 BAV 亚型未观察到显著关联。结论 SAVR 后新发 LBBB 与随访期间全因死亡率增加相关，与 TAV-AS 患者相比，BAV AS 患者的并发症更常见。右冠状动脉和非冠状动脉瓣融合的 BAV-AS 患者在 SAVR 后发生传导障碍的风险增加。在管理这些患者时，应考虑这一点。