OBJECTIVETo determine the prevalence and to identify risk factors of peri-procedure electrical storm (ES) in patients with acute myocardial infarction (AMI) underwent emergency percutaneous coronary intervention (PCI).

METHODSThe clinical data of 228 AMI patients underwent emergency PCI were retrospectively analyzed and patients were divided into ES group (n = 39) and non-ES (n = 189) group. ES was referred to spontaneous ventricular tachycardia or ventricular fibrillation occurring twice or more within 24 h and requiring emergency treatment including anti-arrhythmic medicine and/or cardioversion or defibrillation.

RESULTSES was diagnosed in 39 out of 228 patients (17.1%) during peri-procedure stage. The incidence of ES in patients with various infarct related arteries (IRA) was as follows: 55.6% with left main artery (LM), 23.7% with right coronary artery (RCA), 12.4% with anterior descending branch (LAD) and 0 with left circumflex artery (LCX). Older age, lager diameter of IRA, higher concentration of CK-MB and cTnT, higher incidence of reperfusion arrhythmia (RA), lower grade of TIMI after PCI and higher mortality were associated with increased risks of ES (The P value was 0.043, 0.012, 0.036, 0.018, 0.001, 0.049, respectively). Gender, systolic pressure, diastolic pressure, random blood glucose level, white blood count and concentration of hs-CRP were similar between ES and non-ES patients. Logistic analysis showed that the diameter of IRA (OR 2.381, 95%CI 1.127-5.028, P = 0.023), TIMI grade of IRA after PCI (OR 4.744, 95% CI 1.773-12.691, P = 0.002) and RA (OR 12.680, 95% CI 4.360-36.879, P = 0.000) were the independent risk factors of per-procedure ES in AMI patients underwent emergency PCI.

CONCLUSIONSThe AMI patients with LM as IRA had the highest incidence of ES during emergency PCI and the diameter of IRA, TIMI grade of IRA after PCI and RA were independent risk factors for the development of ES during peri-PCI stage.