Prognostic Implications of the NT-ProBNP Level and Left Atrial Size in Non-Ischemic Dilated Cardiomyopathy

Abstract

The ratio of peak early diastolic mitral inflow to annular velocity (E/E') and left atrial size could provide prognosis on congestive heart failure (CHF). N-terminal Pro B-type natriuretic peptide (NT-ProBNP) has also been useful for predicting adverse cardiac events. However, it is not clear how these parameters compare with conventional risk factors. Thus, we investigated whether E/E', left atrial dimension index (LADI) and NT-ProBNP would predict adverse events and add incremental value to conventional risk factors, even in non-ischemic advanced dilated cardiomyopathy (DCM). Both NT-ProBNP and echocardiography were evaluated in 105 patients. The cardiac events were defined as the composite of cardiac death and re-admission for CHF. At follow up, cardiac events occurred in 24 patients who had high NT-ProBNP and showed higher LADI and E/E'. In multivariate analysis, both NT-ProBNP and LADI, but not E/E', remained as independent predictors; patients with both increased LADI and NT-ProBNP had a 27-fold higher risk of cardiac events than those without any risk factors (p = 0.003). Moreover, LADI and NT-ProBNP showed a better incremental prognostic value over conventional risk factors (global chi-square increase from 7 to 17 to 49, p = 0.003, p < 0.001, respectively). Both NT-ProBNP and LADI might have the most predictable power, particularly in non-ischemic advanced DCM.