The CPET-HFpEF score: simplifying the diagnosis of heart failure with preserved ejection fraction
T NitschkeAbstract
Introduction
Diagnosing heart failure with preserved ejection fraction (HFpEF) remains challenging. For noninvasive diagnosis, two multiparameter risk scores are commonly used: the HFA-PEFF and the H2FPEF-scoring systems. Both integrate morphological evidence of structural heart disease from echocardiography, historical features, and/or laboratory assessment of natriuretic peptides. However, diagnostic uncertainty persists when these assessments are inconclusive. To simplify HFpEF diagnosis in patients with unexplained exercise intolerance and dyspnoea, we developed a noninvasive score that is based on cardiopulmonary exercise testing (CPET) parameters.
Methods / results
CPET is the gold standard for determining the cause of unexplained dyspnoea and/or exercise intolerance, the key symptoms of heart failure. We combined the five CPET parameters VO2 peak indexed by bodyweight, VE/VCO2 slope, oxygen uptake efficiency slope (OUES), VO2/WR slope, the increase in PetCO2 during exercise (PetCO2 delta) and added the NT-proBNP value. Thresholds were defined as follows: VO2peak indexed by body weight < 20 ml/min/kg, VE/VCO2 slope > 30, OUES ≤ 1,6, VO2/WR slope < 8 ml/min/W, PetCO2 delta ≤ 4, and NT-proBNP ≥ 300 pg/ml. Patients received 1 point for each parameter laying above threshold, with a total score of ≥ 4 points confirming the diagnosis of HFpEF. The score was applied to 130 patients: 61 with the diagnosis of HFpEF (confirmed by a HFA-PEFF-score 5 or 6) and 69 patients with an unlikely diagnosis of heart failure. Of the 61 patients with the diagnosis of HFpEF, 58 had a CPET-HFpEF score ≥ 4, and only one patient in the group with no heart failure had a positive score.
Conclusion
The CPET-HFpEF score enables confirmation of HFpEF in patients with exercise intolerance and dyspnoea using a single, comprehensive whole-body testing approachGraphical abstract