Isolated knee extensor exercise training improves skeletal muscle vasodilation, blood flow, and functional capacity in patients with HFpEF

Patients with HFpEF experience severe exercise intolerance due in part to peripheral vascular and skeletal muscle impairments. Interventions targeting peripheral adaptations to exercise training may reverse vascular dysfunction, increase peripheral oxidative capacity, and improve functional capacity in HFpEF. Determine if 8 weeks of isolated knee extension exercise (KE) training will reverse vascular dysfunction, peripheral oxygen utilization, and exercise capacity in patients with HFpEF. Nine HFpEF patients (66 +/- 5 years, 6 females) performed graded IKE exercise (5, 10, and 15 W) and maximal exercise testing (cycle ergometer) before and after IKE training (3x/week, 30 min/leg). Femoral blood flow (ultrasound) and leg vascular conductance (LVC; index of vasodilation) were measured during graded IKE exercise. Peak pulmonary oxygen uptake ((V)over dotO(2); Douglas bags) and cardiac output (Q(C); acetylene rebreathe) were measured during graded maximal cycle exercise. IKE training improved LVC (pre: 810 +/- 417, post: 1234 +/- 347 ml/min/100 mmHg; p = 0.01) during 15 W IKE exercise and increased functional capacity by 13% (peak (V)over dotO(2) during cycle ergometry; pre:12.4 +/- 5.2, post: 14.0 +/- 6.0 ml/min/kg; p = 0.01). The improvement in peak (V)over dotO(2) was independent of changes in (Q)over dotc (pre:12.7 +/- 3.5, post: 13.2 +/- 3.9 L/min; p = 0.26) and due primarily to increased a-vO(2) difference (pre: 10.3 +/- 1.6, post: 11.0 +/- 1.7; p = 0.02). IKE training improved vasodilation and functional capacity in patients with HFpEF. Exercise interventions aimed at increasing peripheral oxidative capacity may be effective therapeutic options for HFpEF patients.

Automated summary

Exercise training targeting peripheral adaptations can reverse vascular dysfunction and improve functional capacity in patients with HFpEF. Isolated knee extension exercise (IKE) training for 8 weeks improved vasodilation and functional capacity in HFpEF patients.