Peak oxygen consumption (VO(2)) and ventilatory efficiency (minute ventilation/carbon dioxide output [VE/VCO(2)] slope) are prognostically important in heart failure (HF). The purpose of the present study was to compare the prognostic characteristics of these variables between Caucasian and African American patients. A total of 662 HF patients (455 Caucasian/207 African American) underwent cardiopulmonary exercise testing and were tracked for major cardiac events. The VE/VCO(2) slope was the strongest prognostic marker (chi-square >or=18.9, P<.001), irrespective of race. While peak VO(2) was a significant univariate predictor in both Caucasian (chi-square 42.0, P<.001) and African American (5.2, P=.02) subgroups, it was only retained in the Caucasian multivariate regression. The lack of predictive value of peak VO(2) in the African American subgroup was due to its lack of prognostic significance in female patients. While the VE/VCO(2) slope was the most robust prognostic marker in both Caucasian and African American patients, the predictive ability of peak VO(2) seems to be influenced by race and sex.
(c) 2008 Le Jacq