The sex-specific impact of systolic hypertension and systolic blood pressure on arterial-ventricular coupling at rest and during exercise

In healthy subjects the arterial system and the left ventricle (LV) are tightly coupled at rest to optimize cardiac performance. Systolic hypertension (SH) is a major risk factor for heart failure and is associated with structural and functional alterations in the arteries and the LV. The effects of SH and resting systolic blood pressure (SBP) on arterial-ventricular coupling (EaI/ELVI) at rest, at peak exercise, and during recovery are not well described. We noninvasively characterized EaI/ELVI as end-systolic volume index/stroke volume index in subjects who were normotensive (NT, n = 203) or had SH (brachial SBP >= 140 mmHg, n = 79). Cardiac volumes were measured at rest and throughout exhaustive upright cycle exercise with gated blood pool scans. EaI/ELVI reserve was calculated by subtracting peak from resting EaI/ELVI. At rest, EaI/ELVI did not differ between SH and NT men but was 23% (P = 0.001) lower in SH vs. NT women. EaI/ELVI did not differ between SH and NT men or women at peak exercise or during recovery. Nevertheless, EaI/ELVI reserve was 61% (P = 0.001) lower in SH vs. NT women. Similarly, resting SBP (as a continuous variable) was not associated with EaI/ELVI in men (beta = -0.12, P = 0.17) but was inversely associated with EaI/ELVI in women (beta = -0.47, P < 0.001). SH and a higher resting brachial SBP are associated with a lower EaI/ELVI at rest in women but not in men, and SH women have an attenuated EaI/ELVI reserve. Whether a smaller EaI/ELVI reserve leads to functional limitations warrants further examination.