Incidence of Ventricular Fibrillation and Sustained Ventricular Tachycardia Complicating Non-ST Segment Elevation Myocardial Infarction

Abstract

Background: Primary ventricular fibrillation (VF) and sustained ventricular tachycardia (VT) are potentially lethal complications in patients suffering from acute myocardial infarction (MI). In contrast with the profound data regarding the incidence and prognostic value of ventricular arrhythmias in ST elevation myocardial infarction (STEMI) patients, data regarding contemporary non-ST elevation myocardial infarction (NSTEMI) patients with ventricular arrhythmias is scarce. The aim of the current study was to investigate the incidence of VF/VT complicating NSTEMI among patients admitted to an intensive coronary care unit (ICCU). Methods: Prospective, single-center study of patients diagnosed with NSTEMI admitted to ICCU between June 2019 and December 2022. Data including demographics, presenting symptoms, comorbid conditions, and physical examination, as well as laboratory and imaging data, were analyzed. Patients were continuously monitored for arrhythmias during their admission. The study endpoint was the development of VF/sustained VT during admission. Results: A total of 732 patients were admitted to ICCU with a diagnosis of NSTEMI. Of them, six (0.8%) patients developed VF/VT during their admission. Nevertheless, three were excluded after they were misdiagnosed with NSTEMI instead of posterior ST elevation myocardial infarction (STEMI). Hence, only three (0.4%) NSTEMI patients had VF/VT during admission. None of the patients died during 1-year follow-up. Conclusions: VF/VT in NSTEMI patients treated according to contemporary guidelines including early invasive strategy is rare, suggesting these patients may not need routine monitoring and ICCU setup.

Keywords: ICCU; NSTEMI; arrhythmias; infarction; myocardial.