Aim: The aim of this study was to assess the predictive value of electrocardiographic, echocardiographic and neurohumoral parameters for adverse outcomes in non-ischaemic dilated cardiomyopathy patients with sinus rhythm.
Methods: Seventy-eight patients with non-ischaemic dilated cardiomyopathy (LVEF < 40%) and sinus rhythm were enrolled. All patients underwent electrocardiographic, echocardiographic examination and coronary angiography. Blood samples for plasma NT pro-BNP levels were obtained at rest, following echocardiographic examination. Patients were followed up for clinical end points of death from worsening heart failure, sudden cardiac death and heart transplantation.
Results: The study population consisted of 24 (30.8%) women and 54 (69.2%) men. Forty-four patients (65.4%) suffered from clinical end points during a mean of 1278 +/- 188 days follow-up; cardiac transplantation was performed in 5 (11%), sudden cardiac death occurred in 10 (23%) and death due to worsening heart failure in 29 (66%) patients. The patients were grouped according to the presence (group 1, 44 patients) or absence (group 2, 34 patients) of clinical end points. The patients in group 1 had lower systolic blood pressures (P = 0.006) and higher NYHA functional classes (P < 0.0001). When echocardiographic parameters and NT pro-BNP values were compared, the patients in group 1 had lower left ventricular ejection fractions (P < 0.0001), higher E/A ratios (P < 0.0001), shorter E wave deceleration times (P = 0.004), pulmonary acceleration times (P < 0.0001) and isovolumetric relaxation times (P = 0.03), increased mitral regurgitant volumes (P = 0.033) and higher plasma NT pro-BNP levels (P < 0.0001). There was no significant difference between the two groups regarding electrocardiographic parameters. In univariate analysis, the prognostic predictors of life expectancy were identified as plasma NT pro-BNP, NYHA functional class, left ventricular ejection fraction, E/A ratio and E wave deceleration time. However, in multivariate analysis by logistic regression only plasma NT pro-BNP was determined as independent predictor of life expectancy (P = 0.04, HR (95% CI) = 1.0003 (1.0000-1.0007), chi2 = 3.9).
Conclusion: Electrocardiographic parameters failed to predict clinical end points in this group of patients. Plasma NT pro-BNP is a useful biochemical marker to define the high-risk group that warrants closer follow-up in dilated cardiomyopathy patients with sinus rhythm.