Abstract
OBJECTIVE: To assess the impact of in-hospital late ventricular fibrillation (VF) (>48 hours) on the 1-year mortality risk among patients presenting with acute myocardial infarction (AMI) who survived the index hospitalisation. DESIGN: Retrospective cohort study estimating the incidence rates of late VF following AMI and the associated 1-year risk of all-cause mortality. SETTING: Cardiac intensive care units (CICUs) in Israel between the years 2000 and 2018. PARTICIPANTS: Patients presenting with AMI (ST-segment elevation MI (STEMI) and non-ST-segment elevation MI (NSTEMI)) who were admitted to CICUs. RESULTS: A total of 14 280 consecutive AMI patients of whom 118 developed late VF and 68 of these survived the index hospitalisation. Patients with late VF had higher mortality rates within 1 year following AMI overall (54.8% vs 10.2%, p<0.01), among STEMI patients (54.7% vs 10%, p<0.01) and among those with NSTEMI (55.2% vs 10.5%, p<0.01). Late VF post-MI was found associated with increased risk of 1-year mortality (adjusted HR (aHR) 3.25, 95% CI (1.98 to 5.34), p<0.01). While this association was statistically significant among STEMI patients (aHR 3.6, 95% CI (2.06 to 6.30), p<0.01), it was not statistically significant among NSTEMI patients (aHR=1.87, 95% CI (0.6 to 5.84), p=0.29). CONCLUSIONS: Late VF was found to be associated with increased 1-year mortality risk among patients presenting with AMI. However, this association was only significant among STEMI patients, but not NSTEMI patients.