Abstract 6087: Fragmented QRS Complex on 12-lead ECG Developed During the First 48 Hours after Acute Myocardial Infarction Predicts Mortality
Fragmented QRS complex (fQRS) signifies myocardial infarction (MI) scar. Myocardial scar acts as a substrate for ventricular arrhythmias and a risk for death. We postulated that the development of new fQRS during the first 48 hours after an acute MI signifies mortality. Serial ECGs of 896 pts with acute coronary syndrome (ACS) and their mortality during follow-up were studied. MI was diagnosed by history, ECG and elevated cardiac enzymes. Serial ECGs were recorded at presentation, 8 hours, 16 hours and 24 – 48 hours. The fQRS on 12-lead ECG was defined by the presence of fragmented QRS, notched R or S wave, or RSR′ pattern without any bundle branch block, in at least 2 contiguous leads in one of the coronary artery territories (LAD: lead V1 to V6, LCx: lead I, aVL and V6, and RCA: lead II, III and aVF). The MI group (n =441, 98.4% males, age 63±11 yrs) and the control (unstable angina) group (n=455, 97.1% males, age 61±11 yrs, P=NS). 104 (24%) patients had STMI and 337 (76%) patients had NSTMI. fQRS developed in a significantly higher number of patients in the MI group as compared to the control group (224 [50.8%] vs. 17 [3.7%], p<0.001), respectively. New Q-waves developed in 122 (27.7%) and 2 (0.4%) patients in MI group and control group, respectively. fQRS was a multivariate predictor of mortality in ACS group as well as in the MI group, whereas Q wave did not predict mortality during a 23+/−17 months of follow-up. Kaplan-Meier survival curve revealed a significantly higher mortality in fQRS vs. non-fQRS group (p=0.001),. The development of fQRS within the first 48 hours of ACS patients predicts mortality during follow-up in patients with MI.