Pulmonary capillary wedge pressure during exercise and long-term mortality in patients with suspected heart failure with preserved ejection fraction

Abstract

Aims: In patients with suspected heart failure with preserved ejection fraction (HFpEF), invasive exercise testing may be considered when measurements at rest are inconclusive. However, the prognostic impact of invasive exercise testing is uncertain, so far.

Methods and results: We retrospectively analysed mortality in 355 patients [mean age 61.2 ± 11.3 years, 235 (66.2%) women] with unexplained dyspnoea and suspected HFpEF. During an invasive haemodynamic stress test 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 recorded. Both PCWP at rest and PCWL were significant and independent predictors of long-term mortality. Adding PCWL to PCWP at rest improved reclassification of patients into survivors or non-survivors with a net reclassification improvement (NRI) of 0.56 (95% CI: 0.29-0.83; P < 0.001). Ten-year mortality was 6.6% in subjects with low PCWP at rest (≤ 12 mmHg) and low PCWL (≤ 25.5 mmHg/W/kg); 28.2% in patients with low PCWP and high PCWL and 35.2% in those with high PCWP and high PCWL. Compared with patients with low PCWP and low PCWL, the adjusted hazard ratio for mortality was 2.37 (95% CI: 1.09-5.17; P = 0.029) for the low-PCWP/high-PCWL group and 4.75 (95% CI: 1.90-11.84; P < 0.001) for patients with high PCWP/high PCWL.

Conclusion: In patients with suspected HFpEF, invasive exercise testing substantially improves prediction of long-term mortality. An excessive rise of PCWP during exercise despite normal PCWP at rest is associated with increased mortality and may be considered as early HFpEF.

Keywords: Exercise haemodynamics; Heart failure with preserved ejection fraction; Mortality; Pulmonary capillary wedge pressure.