Prognostic impact of ventricular tachycardia/fibrillation timing on cardio-vascular death in STEMI patients: 5 years of follow-up

Abstract Objectives Ventricular tachycardia (VT) and ventricular fibrillation (VF) are life-threatening arrhythmias that have negative impact on prognosis. This study investigated the relationship between the timing of VT or VF and long-term prognosis among ST-elevation myocardial infarction (STEMI) patients. Background It is unknown whether the timing of VT/VF occurrence affects the prognosis of patients with STEMI. Methods From 2001 to 2011 among 1621 STEMI patients (mean age 54,4±9,3 years) who participated in a prospective study, 221 (13.6%) had VT/VF during in-hospital stay. The mean time from STEMI symptoms onset was 4,5±0,1 h. 632 patients underwent TLT (39.0%), 267 (16.5%) - primary PCI. 772 (44,5%) patients did not undergo revascularization due to spontaneous recanalization or late admission. Patients with VT/VF were divided into two groups: early VT/VF - within 24 hour (h) of admission, 154 patients and late VT/VF - >24 h after admission, 67 patients. Patients have been monitored for 5 years of follow-up (FU). Cardiovascular (CV) death was the primary end-point. Results Patients with VT/VF were more likely to have cardiogenic shock, Killip Class II-III, AV block, and recurrent MI. Among STEMI patients the frequency of VT/VF occurrence was higher in patients with TLT – 19,0% and PTCA - 15,0% in compare to those without revascularization - 7,9%. However, the late VT/VF was 3.4 times less frequent among patients with TLT, 2.9 times - in PTCA, and twice less in patients without revascularization, compared to patients with early VT/VF. During FU long-term mortality has differed (Fig. 1). Kaplan-Mayer curves have significantly separated in late VT/VF group (p<0.01) during the first year (Fig. 2). Independent predictors of CV death in STEMI patients with late VT/VF were: higher Killip class (OR: 1.372, 95%CI 1.023-2.174, p<0.01), and higher peak CK-MB (OR: 1.031, 95% CI: 1.014-1.048, p<0.05). Conclusions VT and VF are frequent complications in STEMI and are powerful and independent predictors of 5-year survival. The timing of VT/VF occurrence had a peak during the first 24 h. However, patients with late VT/VF are at high risk of CV death in long-term FU and therefore require an individualized approach.