Neuromuscular electric stimulation enhances endothelial vascular control and hemodynamic function in paretic upper extremities of patients with stroke.
OBJECTIVE
To investigate the effects of neuromuscular electric stimulation (NMES) on endothelial vascular control and hemodynamic function in patients in rehabilitation after acute stroke.


METHODS
Before-after trial.


METHODS
Inpatients in a tertiary hospital.


METHODS
Sixteen stroke patients (11 women, 5 men) with a mean age of 60.6+/-19.5 years.


METHODS
All patients received NMES for paretic wrist extensor and flexor muscles 30 minutes daily, 5 days a week, for 4 weeks. The nonparetic upper extremities, which served as controls, did not receive NMES.


METHODS
Laser Doppler perfusion testing was conducted to measure cutaneous microcirculatory responses to transdermal iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP), as specific endothelium-dependent and -independent vasodilators, respectively. Arterial and venous hemodynamic function was also measured by impedance plethysmography.


RESULTS
Before NMES treatment, the venous capacity and compliance of the paretic extremities did not differ significantly from those of the nonparetic extremities. However, hyperemic arterial inflow, ACh-induced cutaneous perfusion, and the ratio of ACh- to SNP-induced cutaneous perfusion were lower in the paretic than in the nonparetic extremities. After NMES treatment, hyperemic arterial inflow and venous outflow increased by 21.5% and 57.2%, respectively, in the paretic extremities (P<.05). ACh-induced cutaneous perfusion and the ratio of ACh- to SNP-induced cutaneous perfusion were also significantly enhanced in the paretic extremities. In contrast, hyperemic arterial inflow decreased by 39.6% in the nonparetic extremities (P<.05), and endothelium-dependent cutaneous vasodilation also decreased significantly.


CONCLUSIONS
NMES therapy may enhance the hyperemic arterial response and endothelium-dependent dilation in skin vasculature in the paretic upper extremities of patients with stroke.
Wang
Jong-Shyan
JS
Graduate Institute of Rehabilitation Sciences and Center for Gerontological Research, Chang-Gung University, Tao-Yuan, Taipei, Taiwan 10016.
Chen
Ssu-Yuan
SY
Lan
Ching
C
Wong
May-Kuen
MK
Lai
Jin-Shin
JS
D000109:Acetylcholine / Q000494:pharmacology; D000328:Adult; D000368:Aged; D002543:Cerebral Hemorrhage / Q000534:rehabilitation; D002544:Cerebral Infarction / Q000534:rehabilitation; D004599:Electric Stimulation Therapy; D004730:Endothelium, Vascular / Q000187:drug effects; D005260:Female; D005296:Ferrous Compounds; D006439:Hemodynamics; D006801:Humans; D007478:Iontophoresis; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D009599:Nitroprusside / Q000494:pharmacology; D010291:Paresis / Q000534:rehabilitation*; D000071939:Stroke Rehabilitation; D034941:Upper Extremity; D014664:Vasodilation; D014665:Vasodilator Agents / Q000494:pharmacology
D005296:Ferrous Compounds; D014665:Vasodilator Agents; D009599:Nitroprusside; C020748:ferrous sulfate; D000109:Acetylcholine