Assessing right ventricular to pulmonary circulation reserve during exercise in heart failure patients with depressed right ventricular function at rest provides relevant clinical insights

Purpose: Right ventricular (RV)-pulmonary circulation (PC) uncoupling plays a key role in HF syndrome carrying a remarkable risk of death. Assessing the adaptations of tricuspid annular systolic excursion (TAPSE), as RV systolic function indicator, and pulmonary artery systolic pressure (PASP) may provide important insights on the functional reserve of the right heart (RH). Objectives: In a group of HF patients with significant RH disease we aimed at assessing the functional RV-PC reserve during a symptom-limited cardiopulmonary exercise testing (CPET). Methods and Results: 24 HF patients (mean age 66; male 65%; NYHA II 30%, III 63%, IV 7%) with an average TAPSE and PASP of 13 mm and 43 mmHg, respectively underwent a maximal CPET (bike, personalized incremental ramp) combined with Echo-Doppler assessment. The table reports the main clinical characteristics and results looking at patients with a preserved vs impaired RV-PC response. Interestingly, for similar degree of LV function, remodeling and RV function impairment at rest, 2 different exercise phenotypes were observed and patients with impaired exercise RV-PC reserve (higher PASP/TAPSE) exhibited a severely reduced exercise performance (peak VO2 and workload). Conclusions: An impaired RH function at rest may not invariably lead to an impaired RV-PC adaptation during exercise. Testing the degree of RV functional reserve adaptations during maximal exercise seems worth to be unmasked even in the advance stages of the disease. Whether a preserved RV-PC reserve may translate in a more favorable response to therapeutic interventions needs to be tested in larger and specifically designed trials.