Abstract 2151: Fragmented QRS in Body Surface Potential Mapping Predicts Cardiac Death and Hospitalizations after Myocardial Infarction
Increased QRS fragmentation in visual inspection of 12-lead ECG has shown association with cardiac events in post-myocardial infarction (MI) patients. We investigated if user-independent computerized intra-QRS fragmentation analysis predicts cardiac deaths (CD) and heart failure hospitalizations (HFH) after acute MI. Patients (n= 158) with acute MI and left ventricular ejection fraction (LVEF) < 50% were studied. Mean age was 61±10 years and left ventricular ejection fraction 40 ± 6%. A 120-lead body surface potential mapping was performed at hospital discharge. After signal-averaging and binomial filtering QRS fragmentation was computed as the number of extrema within the whole QRS (fragmentation index M). QRS duration (QRSd) was computed for comparison. During a mean follow-up of 51 months 15 patients suffered cardiac death and 23 were hospitalized for HF. Both M and QRSd were significantly larger in patients with events. Using the mean value + 1SD as cut-point both parameters were univariate predictors of CD and HFH. In multivariate analysis including age, sex, LVEF, bundle branch block, previous MI, atrial fibrillation, and diabetes M was an independent predictor for cardiac death and HFH (HR 8.7 for CD and 3.8 for HFH) whereas QRSd only predicted HFH (HR 4.6). M showed adequate positive (PPA) and excellent negative (NPA) predictive accuracy, which were further improved when combined to LVEF < 40% (Table⇓). Increased QRS fragmentation in post-infarction patients predicts cardiac deaths and progression of heart failure. A computer-based automatic fragmentation analysis is a stronger predictor than QRS prolongation.