P-Wave Dispersion and Left Atrial Volume Index as Predictors in Heart Failure

Background: Studies have shown that P-wave dispersion (PWD) and left atrial volume index (LAVi) are predictors of cardiovascular events (CE). Objective: To verify the prognostic value of PWD and LAVi for the occurrence of CE in patients with heart failure (HF). Methods: This was a longitudinal prospective study of 78 consecutive patients with a mean age of 47.2 years, of which 52 were males. Patients had stable HF and underwent clinical evaluation, electrocardiogram and echocardiogram assessments, with a follow-up of 26.5 months. Results: The means of the variables were: 50 ms for PWD and 35.5 mL/m(2) for LAVi. Considering PWD >= 40 ms and, as reference, LAVi >= 28 mL/m(2), the positive predictive value of PWD was 87.5% and the negative predictive value was 76.9%. During follow-up, 21 patients had CE. There was an association between left atrial measurements, left ventricular volumes, ejection fraction and CE. There was no association between PWD and CE. At the multivariate analysis, the left atrium and LAVi were predictors of events (p = 0.00 and 0.02). Through the operating characteristic curve for the variable stable CE, areas of 0.80 and 0.69 were obtained for LAVi (p = 0.00) and LAVi >= 28 mL/m(2) (p = 0.01). Survival curves (Kaplan-Meier) free of those events for LAVi >= 28 mL/m(2) and for Chagas disease etiology showed an odds ratio of 14.4 (p = 0.00) and 3.2 (p = 0.03). There was no difference in outcome between patients with ischemic and nonischemic heart failure. Conclusion: PWD was not correlated to CE. LAVi was an independent predictor of CE, and chagasic patients showed worse outcomes. (Arq Bras Cardiol. 2013;100(1):67-74)