Background Exercise training improves neurovascular control and functional capacity in heart failure (HF) patients. However, the influence of the aetiology on these benefits is unknown. We compared the effects of exercise training on neurovascular control and functional capacity in idiopathic, ischaemic and hypertensive HF patients. Design Subjects consisted of 45 exercise-trained HF patients from our database (2000-2015), aged 40-70 years old, functional class II/III and ejection fraction ≤40%, and they were divided into three groups: idiopathic ( n = 11), ischaemic ( n = 18) and hypertensive ( n = 16). Methods Functional capacity was determined by cardiopulmonary exercise testing. Muscle sympathetic nerve activity (MSNA) was recorded by microneurography. Forearm blood flow (FBF) was measured by venous occlusion plethysmography. Results Four months of exercise training significantly reduced MSNA and significantly increased FBF in all groups. However, the relative reduction in MSNA was greater in hypertensive patients compared with that in idiopathic patients (frequency: -34% vs . -15%, p = 0.01; incidence: -31% vs . -12%, p = 0.02). No differences were found between hypertensive patients and ischaemic patients. The relative increase in FBF was greater in hypertensive patients than in ischaemic and idiopathic patients (42% vs. 15% and 17%, respectively, p = 0.02). The relative increase in forearm vascular conductance was greater in hypertensive patients compared with those in ischaemic and idiopathic patients (57% vs . 13% and 26%, respectively, p = 0.001). Exercise training significantly and similarly increased peak oxygen consumption in all groups. Conclusion The exercise-induced improvement in neurovascular control is more pronounced in hypertensive HF patients than in idiopathic and ischaemic HF patients. The increase in functional capacity is independent of aetiology.
Keywords: Heart failure; exercise training; forearm blood flow; muscle sympathetic nerve activity.