Department of Cardiology, The Alfred Hospital, Commercial Road, Melbourne, Australia.
Imaging Research, Baker Heart and Diabetes Institute, Commercial Road, Melbourne, Australia.
Eur Heart J. 2019 Feb 7;40(6):542-550. doi: 10.1093/eurheartj/ehy437.
In patients with non-ischaemic cardiomyopathy (NICM), the mortality benefit of a primary prevention implantable cardioverter-defibrillator (ICD) has been challenged. Left ventricular (LV) scar identified by cardiac magnetic resonance (CMR) imaging is associated with a high risk of malignant arrhythmia in NICM. We aimed to determine the impact of LV scar on the mortality benefit from a primary prevention ICD in NICM.
We recruited 452 consecutive heart failure patients [New York Heart Association (NYHA) Class II/III] with NICM and LV ejection fraction ≤35% from a state-wide CMR service. All patients fulfilled European Society of Cardiology guidelines for primary prevention ICD implantation; however, the decision to implant was at the treating physician's discretion. Baseline clinical and CMR data were recorded prospectively and heart failure mortality risk (MAGGIC score) was calculated. The primary study outcome measurement was all-cause mortality based on presence or absence of ICD, stratified by LV scar. Median follow-up was 37.9 months and there was no difference in MAGGIC score between those who did and did not receive a primary prevention ICD (19.30 ± 5.46 vs. 18.90 ± 5.67, P = 0.50). In patients without LV scar, ICD implantation was not associated with improved mortality [hazard ratio (HR) = 1.22, 95% confidence interval (CI): 0.53-2.78, P = 0.64]. In patients with LV scar, ICD implantation was independently associated with reduced mortality (HR = 0.45, 95% CI: 0.26-0.77, P = 0.003).
In patients with NICM, primary prevention ICD implantation is only associated with reduced mortality in patients with LV scar. This may enable more effective selection of NICM patients for ICD implantation compared with current guidelines.
在非缺血性心肌病（NICM）患者中，初级预防植入式心脏复律除颤器（ICD）的死亡率获益受到了挑战。心脏磁共振（CMR）成像识别的左心室（LV）瘢痕与 NICM 中的恶性心律失常风险高相关。我们旨在确定 LV 瘢痕对 NICM 中初级预防 ICD 死亡率获益的影响。
我们从全州范围的 CMR 服务中招募了 452 名连续的 NICM 心力衰竭患者[纽约心脏协会（NYHA）II/III 级]，LV 射血分数≤35%。所有患者均符合欧洲心脏病学会初级预防 ICD 植入指南；然而，植入的决定取决于治疗医生的判断。前瞻性记录基线临床和 CMR 数据，并计算心力衰竭死亡率风险（MAGGIC 评分）。主要研究结果是根据 ICD 的有无，按 LV 瘢痕分层的全因死亡率。中位随访时间为 37.9 个月，接受和未接受初级预防 ICD 的患者的 MAGGIC 评分无差异（19.30±5.46 与 18.90±5.67，P=0.50）。在没有 LV 瘢痕的患者中，ICD 植入与死亡率改善无关[风险比（HR）=1.22，95%置信区间（CI）：0.53-2.78，P=0.64]。在有 LV 瘢痕的患者中，ICD 植入与死亡率降低独立相关（HR=0.45，95%CI：0.26-0.77，P=0.003）。
在 NICM 患者中，初级预防 ICD 植入仅与 LV 瘢痕患者的死亡率降低相关。这可能使 NICM 患者的 ICD 植入选择比目前的指南更有效。
