Cardiopulmonary efficiency, captured by RV-PA coupling, is a key determinant linking cardiopulmonary hemodynamics to autonomic modulation and ventilatory inefficiency during exercise.
Background: Although chemosensitivity plays a role in exercise-induced hyperventilation in cardiopulmonary disorders, the integration of the underlying reflexes with cardiac hemodynamics is not fully understood. We aimed to explore the interplay between right- and left-heart pressure overload, right ventricular-pulmonary arterial (RV-PA) coupling, cardiovascular autonomic modulation, and ventilatory response in patients with cardiopulmonary disorders. Methods: Forty patients underwent echocardiography, cardiopulmonary exercise testing, and right heart catheterization. Spectral analysis of heart rate variability (HRV) was used to assess cardiovascular autonomic modulation of low- (LF) and high-frequency (HF) components, with LF/HF ratio as an index of sympatho-vagal interaction. Heart rate recovery (HRR) quantified vagal reactivation. RV-PA coupling was calculated through the TAPSE/PAPs ratio, and VE/VCO2 slope defined ventilatory inefficiency. Results: Patients were classified as NoPH (no pulmonary hypertension, n=13), PCPH (pre-capillary pulmonary hypertension, n=15), and LVDD (left ventricular diastolic dysfunction, n=12). VE/VCO2 slope was higher in PCPH than LVDD and NoPH (53.9 vs 43.7 vs 42.2, pConclusion: Our findings support a tight interconnection between left- and right-heart hemodynamics, pulmonary circulation, sympatho-vagal control, and ventilatory response during exercise. Although additional mechanisms are involved, cardiopulmonary efficiency, captured by RV-PA coupling, emerges as a key determinant linking cardiopulmonary hemodynamic to autonomic modulation and ventilatory inefficiency.
Vicenzi et al. (Mon,) studied this question.