Abstract 17249: Impacts of Isometric Handgrip Exercise and Post-Exercise Circulatory Arrest on Hemodynamics and Left Ventricular Function in Heart Failure With Preserved Ejection Fraction

Abstract

Introduction: Isometric handgrip (IHG) training at 30% maximal voluntary contraction (MVC) lowers blood pressure (BP) in patients with hypertension and healthy individuals. However, impacts of IHG and post-exercise circulatory arrest (PECA), which isolates the metaboreflex control, on left ventricular (LV) function and hemodynamics have been unclear in patients with heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF). Methods: Sixteen patients with HF (age 63±13 years, 5M:11F, 10HFpEF:6HFrEF) underwent invasive LV pressure-volume assessments using conductance catheter with microtip-manometer during 3min of IHG exercise at 30% MVC, followed by 3 min of PECA. Impacts of IHG and PECA on LV function and hemodynamics were evaluated and compared between HFpEF and HFrEF. Results: During 3 min of IHG at 30% MCV, heart rate increased by 10±8 bpm in HFpEF and by 14±6 bpm in HFrEF. IHG elevated LV end-systolic BP in both HFpEF (134±21 vs. 158±30 mmHg, p<0.01) and HFrEF (119±30 vs. 142±31 mmHg, p<0.01) with no change in stroke volume. There was a trend towards an increase in LV end-diastolic pressure in both groups (HFpEF:14±5 vs. 19±10 mmHg, HFrEF: 15±12 vs. 23±11 mmHg). Time constant of LV relaxation was unchanged by 3 min of IHG in HFpEF (52±14 vs. 54±15 ms), while it was prolonged in HFrEF (48±7 vs. 60±9 ms, p<0.01, groupхtime interaction effect p=0.08). During PECA, LV end-systolic BP decreased in both groups and was maintained higher than baseline throughout PECA only in HFpEF. Conclusions: Although IHG exercise at 30% MVC for 3 min would elevate LV end-systolic and end-diastolic pressures, this IHG exercise has no detrimental effect on LV systolic and diastolic function, especially in HFpEF patients. Chronic effect of IHG training on BP and hemodynamics will need to be evaluated in HFpEF patients who often suffer from arterial hypertension.