The pulse pressure-to-stroke index ratio predicts cardiovascular events and death in uncomplicated hypertension

Abstract

Objectives: The goal of this study was to assess the prognostic power of the pulse pressure-to-stroke index (PP-to-SVi) ratio for cardiovascular events and mortality in patients with uncomplicated hypertension.

Background: The prognostic significance of pulse pressure (PP) has been studied repeatedly, but few data are available on the PP-to-SVi ratio.

Methods: Invasive hemodynamic measurements, including brachial intra-arterial pressure and stroke index by the direct oxygen Fick method, were performed in the period 1972 to 1982 in 192 patients with uncomplicated hypertension; their outcome was ascertained in 1994.

Results: Age at baseline averaged 37 +/- 12 years; brachial artery pressure was 165 mm Hg +/- 30/89 +/- 17 mm Hg; PP averaged 76 mm Hg +/- 18 mm Hg, and the PP-to-SVi ratio was 1.67 mm Hg/(ml/m2) +/- 0.73 mm Hg/(ml/m2). During 3,057 patient years of follow-up, 19 patients died, and 44 experienced at least one fatal or nonfatal cardiovascular event. Cox regression analysis revealed that the PP-to-SVi ratio was a significant predictor of fatal and nonfatal cardiovascular events and of all-cause mortality after control for age and gender (p < 0.01). Its predictive power persisted after additional adjustment for mean arterial pressure and heart rate. Each 0.75-mm Hg/(ml/m2) increase in the PP-to-SVi ratio was independently associated with a 79% increase in the risk of a cardiovascular event (p = 0.01) and a 2.05-fold greater risk of all-cause mortality (p = 0.01).

Conclusions: The PP-to-SVi ratio is a significant and independent predictor of cardiovascular events and mortality in selected patients with uncomplicated hypertension.