Predictors and outcomes of electrical storm in patients with sustained ventricular arrhythmias during acute myocardial infarction
C Guenancia, S Castan, T Brun, S M'rabet, D Degand, R GarciaAbstract
Background
Electrical storm (ES), defined as ≥3 episodes of sustained ventricular tachycardia (VT) or fibrillation (VF) within 24 hours, represents a life-threatening complication of acute myocardial infarction (AMI). Although well described in patients with implantable cardioverter-defibrillators, data regarding ES occurring during the acute phase of AMI are scarce.
Purpose
To identify predictors of ES and to evaluate its short- and long-term prognostic impact among patients presenting with sustained VT/VF during AMI.
Methods
We performed a multicentre retrospective study including all consecutive patients admitted for AMI (with or without ST-segment elevation) complicated by sustained VT or VF between 2012 and 2023 in two university hospitals. ES was defined as ≥3 VT/VF episodes separated by ≥5 min within 24 h or as incessant VT > 12 h. Clinical characteristics, treatment, and outcomes were compared between patients with and without ES. Independent predictors of ES were identified by multivariable logistic regression.
Results
Among 20 118 AMI admissions, 703 (3.5 %) experienced sustained VT/VF, of whom 68 (9.6 %) met criteria for ES. Independent predictors of ES were diabetes mellitus (OR 2.32, 95 % CI 1.18–4.71, p = 0.014), left-ventricular ejection fraction < 35 % at admission (OR 2.32, 1.26–4.24, p = 0.006), absence of revascularisation (OR 2.46, 1.00–6.02, p = 0.049), and delay from AMI onset to first VT/VF > 48 h (OR 2.73, 1.39–5.34, p = 0.003). In-hospital mortality was higher in the ES group (38 % vs 19 %, p < 0.001), driven by cardiogenic shock and heart failure, whereas long-term survival after discharge was similar between groups (56 % at 8 years; p = 0.97). ES patients more frequently required VT ablation (13 % vs 3 %, p < 0.001) and implantable defibrillator placement (21 % vs 4 %, p < 0.001).
Conclusion
ES occurs in approximately 0.3 % of all AMI and 10 % of those with sustained VT/VF. It is associated with markedly increased acute-phase mortality but not with excess long-term mortality among survivors. Diabetes, reduced LVEF, delayed arrhythmia onset > 48 h, and lack of revascularisation independently predict ES during AMI.