The Importance of the Number of Leads with fQRS for Predicting In-Hospital Mortality in Acute STEMI Patients Treated with Primary PCI.

BACKGROUND: Fragmented QRS (fQRS) has been shown to be related to increased cardiovascular mortality and morbidity. However, limited data are available for evaluating the relationship between the number of leads with fQRS and in-hospital all-cause mortality in patients with acute ST segment elevation myocardial infarction (STEMI). The aim of our study is to investigate the prognostic importance of the number of leads with fQRS in acute STEMI patients treated by primary percutaneous coronary intervention (PCI). METHODS: Two hundred ten eligible patients with acute STEMI that underwent primary PCI were enrolled in this study. Each patient's 12-lead electrocardiography (ECG) taken in the first 48 hours was analyzed and the number of leads with fQRS were recorded. RESULTS: The number derivations with fQRS were significantly higher in patients who developed in-hospital mortality than the patients who did not develop in-hospital mortality (2.6 ± 2.6 vs 0.9 ± 1.3; P = 0.002). Also, patients with ≥3 leads with fQRS had higher rate of in-hospital all-cause mortality (23.5% vs 7.4%, P = 0.009), higher frequency of Q wave (67.6% vs 36.9%, P = 0.001), and higher frequency of fQRS with Q wave (67.6% vs 15.9%, P < 0.001) than those patients with <3 leads with fQRS. By a multivariate regression analysis, the number of leads with fQRS was found to be an independent predictor of in-hospital all-cause mortality (odds ratio: 1.415, 95% confidence interval: 1.049-1.909, P = 0.023). CONCLUSIONS: The number of leads with fQRS on 12-lead ECG is an independent predictor of in-hospital all-cause mortality in patients with acute STEMI treated by primary PCI.