VALUE OF A DOPPLER-DERIVED INDEX COMBINING SYSTOLIC AND DIASTOLIC TIME INTERVALS IN PREDICTING OUTCOME IN PRIMARY PULMONARY-HYPERTENSION

Primary pulmonary hypertension is characterized by elevated pulmonary arterial pressure and vascular resistance, frequently producing right heart failure and death. Therefore, the Doppler right ventricular (RV) index, which is a measure of global RV function, could be a useful pr edictor of outcome in primary pulmonary hypertension. The Doppler RV i ndex, defined as the sum of isovolumic contraction time and isovolumic relaxation time divided by ejection time, was retrospectively measure d in 53 patients (38 women, aged 45 +/- 14 years) with primary pulmona ry hypertension. Ejection time was measured from the pulmonary outflow velocity signal. The sum of isovolumic contraction time and isovolumi c relaxation time was obtained by subtracting ejection time from the d uration of tricuspid regurgitation. The Doppler RV index tended to be elevated (median 0.83) compared with normal ranges. Normal Doppler RV index was 0.28 +/- 0.04. After a mean follow-up duration of 2.9 years, 4 patients underwent lung transplantation and 30 patients died; the c ause was cardiac in 28, noncardiac in 1, and uncertain in 1. Univariat ely, the Doppler RV index (chi-square 20.7, p <0.0001), severity of tr icuspid regurgitation (chi-square 8.2, p = 0.004), treatment with calc ium blockers (chi-square 6.6, p = 0.01), heart rate (chi-square 5.1, p = 0.02), and symptom status (chi-square 4.9, p = 0.03) were associate d with adverse outcome (cardiac deaths and lung transplantation). Howe ver, only the Doppler RV index and treatment with calcium blockers wer e independent predictors within the multivariate model. Our results in dicate that the Doppler RV index is a useful predictor of adverse outc ome in patients with primary pulmonary hypertension. (C) 1998 by Excer pta Medica, Inc.