Ventricular-vascular coupling at rest and immediately following maximal exercise in adults with and without multiple sclerosis.

Multiple sclerosis (MS) may impair ventricular-vascular coupling (VVC), a measure of the interaction between the cardiac and vascular systems. We evaluated if VVC differed between individuals with and without MS with similar age-predicted fitness. Individuals with MS (n = 20) and without (CON, n = 18) underwent VVC measurement before and immediately after a maximal incremental cycle test with peak oxygen consumption (VO2peak) measurement. VVC was quantified as the ratio of arterial elastance (EA: end-systolic pressure (ESP)/stroke volume) to ventricular elastance (ELV: ESP/end-systolic volume). ESP was assessed with radial applanation tonometry, and cardiac volumes were obtained from apical four-chamber echocardiography. Sex, BMI and VO2peak were not different between groups. Individuals with MS were older, had higher EA (p < 0.01) and ELV (p = 0.02), but VVC did not differ between groups. After adjustment for age, the group differences in EA and ELV remained significant. VVC was similar between individuals with and without MS, before and immediately after maximal exercise. However, individuals with MS had higher EA and ELV, suggesting higher arterial and ventricular loads. Our data suggest that individuals with MS with similar fitness to controls exhibit higher EA and ELV with preserved coupling.