Ventricular-Arterial Coupling Derived From Proximal Aortic Stiffness and Aerobic Capacity Across the Heart Failure Spectrum

Background: Ventricular-arterial coupling (VAC) can be evaluated as the ratio between arterial stiffness (pulsed wave velocity [PWV]) and myocardial deformation (global longitudinal strain [GLS]). Objectives: This study aimed to evaluate VAC across the spectrum of heart failure (HF). Methods: The authors introduced a Doppler-derived, single-beat technique to estimate aortic arch PWV (aa-PWV) in addition to tonometry-derived carotid-femoral PWV (cf-PWV). They measured PWVs and GLS in 155 healthy controls, 75 subjects at risk of developing HF (American College of Cardiology/American Heart Association stage A-B) and 236 patients in stage C heart failure with preserved ejection fraction (HFpEF) (n = 104) or heart failure with reduced ejection fraction (HFrEF) (n = 132). They evaluated peak oxygen consumption and peripheral extraction using combined cardiopulmonary-echocardiography exercise stress. Results: aa-PWV was obtainable in all subjects and significantly lower than cf-PWV in all subgroups (P < 0.01). PWVs were directly related and increased with age (all P < 0.0001). cf-PWV/GLS was similarly compromised in HFrEF (1.09 ± 0.35) and HFpEF (1.05 ± 0.21), whereas aa-PWV/GLS was more impaired in HFpEF (0.70 ± 0.10) than HFrEF (0.61 ± 0.14; P < 0.01). Stage A-B had values of cf-PWV/GLS and aa-PWV/GLS (0.67 ± 0.27 and 0.48 ± 0.14, respectively) higher than controls (0.46 ± 0.11 and 0.39 ± 0.10, respectively) but lower than stage C (all P < 0.01). Peak arteriovenous oxygen difference (AVO2diff) was inversely related with cf-PWV/GLS and aa-PWV/GLS (all P < 0.01). Although cf-PWV/GLS and aa-PWV/GLS independently predicted peak VO2 in the overall population (adjusted R2 = 0.33 and R2= 0.36; all P < 0.0001), only aa-PWV/GLS was independently associated with flow reserve during exercise (R2 = 0.52; P < 0.0001). Conclusions: Abnormal VAC is directly correlated with greater severity of HF and worse functional capacity. HFpEF shows a worse VAC than HFrEF when expressed by aa-PWV/GLS.