Comprehensive analysis of cardiopulmonary exercise testing and mortality in patients with systolic heart failure: the Henry Ford Hospital cardiopulmonary exercise testing (FIT-CPX) project
Brawner CA, Shafiq A, Aldred HA, Ehrman JK, Leifer ES, Selektor Y, Tita C, Velez M, Williams CT, Schairer JR, Lanfear DE, Keteyian SJ. Comprehensive analysis of cardiopulmonary exercise testing and mortality in patients with systolic heart failure: The henry ford hospital cardiopulmonary exercise testing (fit-cpx) project. J Card Fail. 2015 ;21(9):710-8.
Journal of cardiac failure
BACKGROUND: Many studies have shown a strong association between numerous variables from a cardiopulmonary exercise (CPX) test and prognosis in patients with heart failure with reduced ejection fraction (HFrEF). However, few studies have compared the prognostic value of a majority of these variables simultaneously, so controversy remains regarding optimal interpretation.
METHODS AND RESULTS: This was a retrospective analysis of patients with HFrEF (n = 1,201; age = 55 ± 13 y; 33% female) and a CPX test from 1997 to 2010. Thirty variables from a CPX test were considered in separate adjusted Cox regression analyses to describe the strength of the relation of each to a composite end point of all-cause mortality, left ventricular assist device implantation, or heart transplantation. During a median follow-up of 3.8 years, there were 577 (48.0%) events. The majority of variables were highly significant (P < .001). Among these, percentage of predicted maximum V˙O2 (ppMV˙O2; Wald = 203; P < .001; C-index = 0.73) was similar to VE-VCO2 slope (Wald = 201; P < .001; C = 0.72) and peak V˙O2 (Wald = 161; P < .001; C = 0.72). In addition, there was no significant interaction observed for peak respiratory exchange ratio
CONCLUSIONS: Consistent with prior studies, many CPX test variables were strongly associated with prognosis in patients with HFrEF. The choice of which variable to use is up to the clinician. Renewed attention should be given to ppMV˙O2, which appears to be highly predictive of survival in these patients.
Medical Subject Headings
Cause of Death; Exercise; Exercise Test; Female; Follow-Up Studies; Heart Failure, Systolic; Humans; Male; Middle Aged; Oxygen Consumption; Prognosis; Proportional Hazards Models; Retrospective Studies; Severity of Illness Index; Stroke Volume; Survival Rate; United States