Clinical, hemodynamic, and cardiopulmonary exercise test determinants of survival in patients referred for evaluation of heart failure.
BACKGROUND
Accurate prognosis in chronic heart failure has become increasingly important in assessing the efficacy of treatment and in appropriately allocating scarce resources for transplantation. Previous studies of severe heart failure have been limited by short follow-up periods and few deaths.


OBJECTIVE
To establish clinical, hemodynamic, and cardiopulmonary exercise test determinants of survival in patients with heart failure.


METHODS
Retrospective study.


METHODS
Hospital-based outpatient heart failure clinic.


METHODS
644 patients referred for evaluation of heart failure over 10 years.


METHODS
Age, cause of heart failure, body surface area, cardiac index, ejection fraction, pulmonary capillary wedge pressure, left ventricular dimensions, watts achieved during exercise, heart rate, maximum systolic blood pressure, and oxygen uptake (VO2) at the ventilatory threshold and at peak exercise were measured at baseline. Univariate and multivariate analyses were done for clinical, hemodynamic, and exercise test predictors of death. A Cox hazards model was developed for time of death.


RESULTS
During a mean follow-up period of 4 years, 187 patients (29%) died and 101 underwent transplantation. Actuarial 1-year and 5-year survival rates were 90.5% and 73.4%, respectively. Resting systolic blood pressure, watts achieved, peak VO2, VO2 at the ventilatory threshold, and peak heart rate were greater among survivors than among nonsurvivors. Cause of heart failure (coronary artery disease or cardiomyopathy) was a strong determinant of death (relative risk for coronary artery disease, 1.73; P< 0.01). By multivariate analysis, only peak VO2 was a significant predictor of death. Stratification of peak VO2 above and below 12, 14, and 16 mL/kg per minute demonstrated significant differences in risk for death, but each cut-point predicted risk to a similar degree.


CONCLUSIONS
Peak VO2 outperforms clinical variables, right-heart catheterization data, exercise time, and other exercise test variables in predicting outcome in severe chronic heart failure. Direct measurement of VO2 should be included when clinical or surgical decisions are being made in patients referred for evaluation of heart failure or those considered for transplantation.
Myers
J
J
Palo Alto Veterans Affairs Health Care System, California 94304, USA.
Gullestad
L
L
Vagelos
R
R
Do
D
D
Bellin
D
D
Ross
H
H
Fowler
M B
MB
D000328:Adult; D000368:Aged; D005080:Exercise Test; D005260:Female; D006333:Heart Failure / Q000401:mortality* / Q000503:physiopathology / Q000601:surgery; D006334:Heart Function Tests; D016027:Heart Transplantation; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D016019:Survival Analysis