Accuracy of the isovolumic relaxation time in the emergency diagnosis of new-onset congestive heart failure with preserved left ventricular systolic function in the setting of B-type natriuretic peptide levels in the mid-range.

Despite the fact that B-type natriuretic peptide (BNP) is a useful diagnostic complement to clinical and radiographic data in the emergency diagnosis of acute congestive heart failure, levels of BNP in the mid-range (100-500 pg/ml) are acknowledged to be inconclusive for the diagnosis. We assessed the diagnostic value of the pulsed Doppler-derived isovolumic relaxation time (IVRT) by bedside Doppler echocardiography in the emergency diagnosis of new-onset congestive heart failure with preserved systolic function in 43 patients presenting with acute severe dyspnea and inconclusive BNP levels. A short IVRT <50 ms was a good predictor of acute congestive heart failure in this clinical setting, with a positive predictive value of 94%.