Egbe Alexander C, Pellikka Patricia A, Afzal Arslan, Jain Vaibhav, Thotamgari Sahith, Miranda William R, Connolly Heidi M
Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA.
CJC Open. 2019 Nov 18;2(1):1-7. doi: 10.1016/j.cjco.2019.11.004. eCollection 2020 Jan.
Despite the significant risk of cardiovascular mortality after tetralogy of Fallot (TOF) repair, there are limited data about left ventricular (LV) cardiomyopathy in this population, thus creating important knowledge gaps. This study aims to address some of these knowledge gaps by describing the risk and prognostic implications of LV systolic dysfunction (LVD) after TOF repair.
We performed a cohort study of adult patients after TOF repair with an echocardiographic assessment of LV ejection fraction (LVEF) to determine the association between LVD and cardiovascular events, defined as sustained ventricular tachycardia, aborted sudden death, heart transplantation, or death. Prevalent and incidence LVD were defined as LVEF < 50% at baseline or new decrease in LVEF to < 50% during follow-up, respectively.
Of 574 patients (age 38 ± 13 years), the baseline LVEF was 57% ± 9% and 68 (12%) had prevalent LVD. Cardiovascular events occurred in 126 patients (22%) during 10.5 ± 6.2 years of follow-up. LVEF was an independent predictor of mortality (hazard ratio, 1.16; 95% confidence interval, 1.16-1.24; = 0.003) per 5%-point decrease in LVEF. Among the 357 patients with preserved LVEF and echocardiographic follow-up, incident LVD occurred in 23 (6%) during 3.8 ± 1.6 years of follow-up. Event-free survival was significantly lower in patients with incident LVD compared with patients without incident LVD (87% vs 71%, = 0.021).
Prevalent and incident LVD occurred in 12% and 6% of this cohort, respectively, and were associated with lower event-free survival. Incident LVD suggests the presence of subclinical LV cardiomyopathy, and further studies are required to determine optimal strategies for diagnosing and treating subclinical LV cardiomyopathy to improve outcomes in the population with TOF.
尽管法洛四联症（TOF）修复术后存在显著的心血管死亡风险，但关于该人群左心室（LV）心肌病的数据有限，从而造成了重要的知识空白。本研究旨在通过描述TOF修复术后左心室收缩功能障碍（LVD）的风险及预后影响来填补其中一些知识空白。
我们对TOF修复术后的成年患者进行了一项队列研究，通过超声心动图评估左心室射血分数（LVEF），以确定LVD与心血管事件之间的关联，心血管事件定义为持续性室性心动过速、心脏骤停、心脏移植或死亡。现患LVD和新发LVD分别定义为基线时LVEF<50%或随访期间LVEF新降至<50%。
在574例患者（年龄38±13岁）中，基线LVEF为57%±9%，68例（12%）有现患LVD。在10.5±6.2年的随访期间，126例患者（22%）发生了心血管事件。LVEF每降低5个百分点是死亡率的独立预测因素（风险比，1.16；95%置信区间，1.16 - 1.24；P = 0.003）。在357例LVEF保留且有超声心动图随访的患者中，3.8±1.6年的随访期间有23例（6%）发生新发LVD。新发LVD患者的无事件生存率显著低于无新发LVD的患者（87%对71%，P = 0.021）。
该队列中现患LVD和新发LVD的发生率分别为12%和6%，且与较低的无事件生存率相关。新发LVD提示存在亚临床左心室心肌病，需要进一步研究以确定诊断和治疗亚临床左心室心肌病的最佳策略，从而改善TOF人群的预后。
