Selvaraj Raja J, Rangasamy Sasinthar, Priya Dhivya, Nair Sreekumaran, Pillai Ajith Ananthakrishna, Satheesh Santhosh, Jayaraman Balachander
Department of Cardiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, India.
Department of Cardiology, Mahatma Gandhi Medical College and Research Institute, Pondicherry, India.
Indian Pacing Electrophysiol J. 2021 Mar-Apr;21(2):82-87. doi: 10.1016/j.ipej.2020.12.002. Epub 2020 Dec 19.
This study was conducted to assess the incidence of sudden cardiac death (SCD) in post myocardial infarction patients and to determine the predictive value of various risk markers in identifying cardiac mortality and SCD.
Left ventricular function, arrhythmias on Holter and microvolt T wave alternans (MTWA) were assessed in patients with prior myocardial infarction and ejection fraction ≤ 40%. The primary outcome was a composite of cardiac death and resuscitated cardiac arrest during follow up. Secondary outcomes included total mortality and SCD.
Fifty-eight patients were included in the study. Eight patients (15.5%) died during a mean follow-up of 22.3 ± 6.6 months. Seven of them (12.1%) had SCD. Among the various risk markers studied, left ventricular ejection fraction (LVEF) ≤ 30% (Hazard ratio 5.6, 95% CI 1.39 to 23) and non-sustained ventricular tachycardia (NSVT) in holter (5.7, 95% CI 1.14 to 29) were significantly associated with the primary outcome in multivariate analysis. Other measures, including QRS width, heart rate variability, heart rate turbulence and MTWA showed no association.
Among patients with prior myocardial infarction and reduced left ventricular function, the rate of cardiac death was substantial, with most of these being sudden cardiac death. Both LVEF ≤30% and NSVT were associated with cardiac death whereas only LVEF predicted SCD. Other parameters did not appear useful for prediction of events in these patients. These findings have implications for decision making for the use of implantable cardioverter defibrillators for primary prevention in these patients.
本研究旨在评估心肌梗死后患者心源性猝死（SCD）的发生率，并确定各种风险标志物在识别心脏死亡率和SCD方面的预测价值。
对既往有心肌梗死且射血分数≤40%的患者进行左心室功能、动态心电图心律失常及微伏级T波电交替（MTWA）评估。主要结局为随访期间心源性死亡和复苏成功的心脏骤停的复合终点。次要结局包括总死亡率和SCD。
58例患者纳入研究。在平均22.3±6.6个月的随访期间，8例患者（15.5%）死亡。其中7例（12.1%）为SCD。在研究的各种风险标志物中，多因素分析显示左心室射血分数（LVEF）≤30%（风险比5.6，95%可信区间1.39至23）和动态心电图非持续性室性心动过速（NSVT）（5.7，95%可信区间1.14至29）与主要结局显著相关。其他指标，包括QRS波宽度、心率变异性、心率震荡和MTWA均未显示相关性。
在既往有心肌梗死且左心室功能降低的患者中，心源性死亡率较高，其中大部分为心源性猝死。LVEF≤30%和NSVT均与心源性死亡相关，而只有LVEF可预测SCD。其他参数似乎对预测这些患者的事件无用。这些发现对这些患者使用植入式心脏复律除颤器进行一级预防的决策具有重要意义。
