Navigating unexplained dyspnoea and the role of HFpEF diagnostic scores.

In patients with unexplained dyspnea, heart failure with preserved ejection fraction (HFpEF) is a frequent cause. Diagnostic scores estimate HFpEF probability, but their prognostic role and clinical applicability in this population remain uncertain. This study evaluated the association of HFpEF scores with structural remodeling, functional limitation, and clinical outcomes. This multicenter cohort study included 2,535 patients with unexplained dyspnea who underwent combined cardiopulmonary exercise testing and echocardiography. HFpEF probability was assessed using H₂FPEF, HFA-PEFF, and HFpEF-ABA scores, with patients stratified into risk categories. Higher scores correlated with adverse ventricular and atrial remodeling, impaired exercise capacity, and higher pulmonary pressures, both at rest and during exercise. Intermediate and high-risk categories for HFA-PEFF, H₂FPEF, and HFpEF-ABA scores showed significantly elevated hazard ratios versus the low-risk group: HFA-PEFF (HR 2.62 95%CI 1.56-4.40, p<0.001 and 5.49 95%CI 2.82-10.67, p=0.005), H₂FPEF (HR 2.74 95%CI 1.35-5.89, p<0.001 and 6.21 95%CI 2.86-13.5, p<0.001), and HFpEF-ABA (HR 1.28 95%CI 0.57-2.86, p=0.549 and 2.50 95%CI 1.02-6.14, p=0.046), all p<0.001. Event rates increased stepwise across score categories, reaching 10 per 100 patient-years in the high-score groups. Score performance differed, particularly in the elderly, women, and those with atrial fibrillation. Incorporating echocardiographic parameters, particularly resting pulmonary pressure, improved HFpEF-ABA prognostic accuracy. In the NT-proBNP subgroup, functional criteria and NT-proBNP remained independent predictors for outcome. HFpEF diagnostic scores reflect the structural and functional disease burden as well as clinical risk in unexplained dyspnea. These scores are complementary and may enhance risk stratification.

Diagnosing heart failure with preserved ejection fraction (HFpEF) remains challenging. Noninvasive diagnostic algorithms have been proposed but not tested against the gold standard, ie, invasive measurement of left ventricular (LV) pressure-volume loops (PVL). This study's aim was to estimate the prevalence of HFpEF in euvolemic patients with unexplained exertional dyspnea by using LV PVL and to validate noninvasive diagnostic algorithms. We included patients with unexplained exertional dyspnea, preserved LV ejection fraction ≥ 50% and without hemodynamically relevant coronary artery disease. Patients were evaluated at rest, during arm ergometric exercise and during temporal preload reduction by right-heart catheterization and real-time continuous LV PVL. HFpEF was defined as either elevated LV filling pressures at rest or during exercise or without elevated filling pressures but with prolonged relaxation or increased LV stiffness. The primary endpoint was the percentage of patients with confirmed HFpEF. Secondary endpoints included differences in the H2FPEF and HFA-PEFF scores in HFpEF vs non-HFpEF patients. We recruited 30 patients, and 28 patients (mean age 64.4 ± 9.7 years, 57% female) were included in the final analysis. Of those patients, 26 (93%) had HFpEF with either elevated (n = 11) or without elevated filling pressures (n = 15). Noninvasive diagnostic scores had excellent specificity but lacked sensitivity for HFpEF. Half of the patients with HFpEF had normal right-heart catheter hemodynamics, but they fulfilled HFpEF diagnostic criteria by showing impaired relaxation or LV chamber stiffness. Further research might focus on understanding the clinical relevance of this group and on improving its detection and treatment.

Utility of HFpEF Diagnostic Scores to Stratify Cardiac Reserve Among Patients With Dyspnea.