RIGHT HEART PULMONARY CIRCULATION UNIT RESPONSE TO EXERCISE IN PATIENTS WITH SYSTEMIC ARTERIAL HYPERTENSION. INSIGHTS FROM THE RIGHT-NET STUDY

Abstract

Objective: Systemic arterial hypertension is the main risk factor for the development of heart failure with preserved ejection fraction (HFpEF). The aim of this study was to assess the right heart-pulmonary circulation unit response to exercise doppler echocardiography (EDE) in patients with hypertension in order to evaluate the capacity of EDE to unmask a pre-HFpEF state. Design and method: EDE was performed in 155 hypertensive patients and in 145 healthy normotensive subjects on a semi-recumbent cycle ergometer with load increments of 25 watts every 2 minutes. Left ventricular (LV) and right ventricular (RV) dimensions, function and hemodynamics were evaluated. Linear mixed models were used to test the interaction between hypertension and age group on the echocardiographic parameters at peak exercise, adjusting for baseline values. Results: Impaired echo-Doppler LV and RV function was observed both at rest and peak exercise in hypertensives compared to healthy subjects. Pulmonary artery systolic pressure (PASP) and pulmonary vascular resistance were higher in the former. The entire population was then divided into tertiles of age: at rest no significant differences were recorded for each age group between hypertensives and normotensives except for E/E’ that was higher in the hypertensives of the middle age tertile. At peak exercise, hypertensives had higher pulmonary artery systolic pressure (PASP) and E/E’ but lower tricuspid annular plane systolic excursion (TAPSE) as age increased, compared to normotensives. Differences in E/E’ and TAPSE between the 2 groups at peak exercise were explained by the interaction between hypertension and age even after adjustment for baseline values (p < 0.001 for E/E’, p = 0.011 for TAPSE). At peak exercise, the oldest group of hypertensive patients had a mean E/E’ of 13.0, suggesting a significant increase in LV diastolic pressure combined with increased PASP. Conclusions: Age and hypertension have a synergistic effect on E/E’ and TAPSE at peak exercise indicating that the detrimental effect of aging on cardiac function is amplified in hypertension. EDE appears a useful tool for unmasking a pre-HFpEF state in hypertension even in patients with controlled resting blood pressure.