ABSTRACT
Aims: Exercise stress testing can stratify specific populations of heart failure patients for mortality risk, but is not universally applied. The aim of the present study was to investigate the prognostic capabilities of invasive exercise testing in a real-world cohort of suspected heart failure patients in whom non-cardiac causes of dyspnea were excluded. Methods: We retrospectively analyzed the survival of 682 patients who underwent right heart catheterization at rest and during exercise between 2007 and 2017 for dyspnea and expected heart failure. Pulmonary capillary wedge pressure (PCWP) at rest and the PCWP response to exercise, expressed as the ratio of PCWP at peak exercise to workload normalized to body weight (PCWL (mmHg/W/kg)), were determined. Mortality data were retrieved from the official German death registry. Results: Over a median follow-up period of 8.5 years, PCWL is a stronger predictor of all-cause mortality than PCWP. Patients featuring a reduced left ventricular ejection fraction (LVEF; <50%), but favorable response to exercise (PCWL <34.7 mmHg/W/kg), have a similar mortality risk to patients with a normal LVEF and low PCWL (hazard ratio (HR) 1.180, 95% CI 0.48−2.91, p = 0.719). Irrespective of LVEF, an increased PCWL during exercise was associated with a significantly increased mortality (HR 1.950 with preserved LVEF, 95% CI 1.12−3.34, p = 0.018; and HR 3.212 with impaired LVEF, 95% CI 1.75−5.70, p < 0.001). Conclusions: In patients with clinical heart failure, invasive exercise testing improves the prediction of mortality. Subjects with a favorable response to exercise have a relatively low mortality irrespective of left ventricular systolic function.
