Investigation of the effects of neuromuscular electrical stimulation in patients with pulmonary arterial hypertension

Objective: To investigate the effects of neuromuscular electrical stimulation (NMES) on peripheral muscles and other physical and psychosocial variables in patients with pulmonary arterial hypertension (PAH). Method: This assessor blind randomized controlled trial included 31 patients with PAH divided as treatment and control groups. For the treatment group, NMES was applied to the bilateral deltoid and quadriceps femoris muscles with 50 Hz for 3 days/week, 8 weeks. Before and after the treatment, the upper and lower limb muscle strength, respiratory muscle strength, muscle cross-sectional area and thickness, augmentation index and pulse wave velocity, exercise capacity, walking speed, functional mobility and balance performances, balance confidence, posturographic balance, anxiety, depression, fatigue perceptions, physical activity level, activities of daily living and quality of life were evaluated. Results: In total, 22 patients (treatment=11, control=11) completed the eight-week follow-up. There was no significant difference in the demographic and clinical characteristics between the patient groups (p>0.05). Patients in the treatment group showed a significant improvement in knee extensor, shoulder flexor and abductor muscle strength, grip strength, maximum expiratory pressure, rectus femoris muscle cross-sectional area and quadriceps femoris muscle thickness, pulse wave velocity, 6 minutes walking distance, functional mobility and balance performance, anxiety, fatigue level, physical activity level, activities of daily living and quality of life from the baseline assessments (p<0.05). Conclusion: This study showed that the NMES intervention increases peripheral muscle strength, muscle cross-sectional area and thickness, exercise capacity, mobility and balance performance, physical activity level, activities of daily living and quality of life, reduced fatigue level, arterial stiffness and anxiety levels in patients with PAH. The NMES intervention is an effective method for cardiopulmonary rehabilitation in patients with PAH.