Right Ventricular-Pulmonary Arterial Coupling and Exercise-induced Pulmonary Congestion in Heart Failure with Reduced and Mildly-reduced Ejection Fraction.

AIMS: We explored the relationship between right ventricular-pulmonary arterial (RV - PA) coupling and exercise pulmonary congestion in heart failure patients with reduced (HFrEF) and mildly reduced (HFmrEF) left ventricle ejection fraction.

METHODS AND

RESULTS

A cohort of 118 HFrEF and HFmrEF patients underwent baseline transthoracic echocardiography and exercise stress echocardiography (ESE), assessing extravascular lung water (EVLW) changes through lung ultrasound (LUS) B-lines. The TAPSE/PAPs ratio served as RV - PA coupling surrogate. Compared to patients with ∆B-lines ≤10, those with ∆B-lines >10 displayed a worse RV-PA coupling both at rest (median TAPSE/PAPs: 0.77 mm/mmHg vs 0.57 mm/mmHg, p = 0.002) and at peak exercise (median TAPSE/PAPs: 0.58 mm/mmHg vs 0.39 mm/mmHg, p < 0.001). Worsening RV - PA coupling at peak effort inversely correlated with exercise extravascular lung water increase, but only in patients with higher peak PAPs (peak PAPs 42-55 mmHg; r = -0.53, p = 0.001).

CONCLUSION

Exercise may induce impairments in RV-PA coupling which hampers lung lymphatic drainage through elevated central venous pressure and increases EVLW. This is especially true for patients with higher peak PAPs values, in which a significant increase in capillary pressure during exercise can occur in absence of the structural pulmonary alterations observed in more advanced stages of HF.