Abstract 15768: Exercise Training Associated With Cardiac Resynchronization Therapy Improves Peripheral Vasoconstriction and Functional Capacity in Heart Failure Patients
Background: Cardiac Resynchronization Therapy (CRT) is known to increase exercise capacity and decrease sympathetic activation in HF. To determine if exercise training (ET) can further increase exercise capacity and decrease muscle sympathetic nerve activity (MSNA), we studied advanced HF patients in whom atriobiventricular pacing had been placed at least a month before.
Methods: Twenty-three HF patients, Functional Class I-III (NYHA), EF<35%, age 18 to 70 years, with CRT for 1 month were consecutive and randomly divided into two groups: Exercise-trained (CRT+ET, n=11) and untrained (CRT-ET, n=12). Ten healthy controls were also studied. MSNA was directly evaluated by microneurography technique and forearm blood flow by venous occlusion plethysmography. Peak VO2 was determined by cardiopulmonary exercise test and cardiac function by echocardiography. ET consisted of three 60-minute exercise sessions per week on a treadmill for four months.
Results: Baseline MSNA was higher (P=0.004) and forearm blood flow was lower (P=0.05) in heart failure patients when compared with healthy controls. CRT+ET decreased MSNA towards healthy control levels (41±8.4 vs 32±3.8 bursts/100beats, P=0.70). Furthermore, CRT+ET increased forearm blood flow (1.6±0.2 vs 1.9±0.1mL/min/100g, P=0.03), EF (28±3.7 vs 34±4.7%, P=0.04) and peak VO2 (19±1.1 vs 22±1.8ml/kg/min, P=0.04). CRT-ET tended to decrease MSNA (P=0.07), but caused no changes in forearm blood flow, peak VO2 and EF.
Conclusions: ET associated with CRT improves neurovascular control, cardiac function and functional capacity in heart failure patients. These findings highlight the importance of including ET in the treatment of heart failure patients submitted to CRT.
- © 2013 by American Heart Association, Inc.