Saturação de oxigênio muscular nos membros inferiores durante uma sessão de ergômetro de braço em pacientes com doença arterial periférica

Abstract

Peripheral artery disease (PAD) is characterized by obstruction of the lower-limb arteries, leading to pain during walking. Arm-crank ergometry (ACE) exercise may improve walking performance; however, its underlying mechanisms remain poorly understood. This study aimed to analyze the acute effects of ACE exercise on leg muscle oxygen saturation (StO₂) in individuals with PAD. Twenty-four participants (68 ± 7 years; 50% men; ankle-brachial index 0.62 ± 0.14) with intermittent claudication symptoms were included. The ACE session consisted of 15 sets of 2 minutes of exercise followed by 2 minutes of rest, maintaining a rating of perceived exertion (RPE) between 13 and 15 on the Borg scale. StO₂, oxyhemoglobin, deoxyhemoglobin, and total hemoglobin were assessed using near-infrared spectroscopy at rest and during exercise. Significant increases in StO₂, oxyhemoglobin, and total hemoglobin were observed during exercise compared with rest (p < 0.005). Deoxyhemoglobin decreased during the first set (p = 0.019) and increased at peak exercise (p < 0.001). RPE was positively correlated with oxyhemoglobin (rho = 0.208; p < 0.001) and total hemoglobin (rho = 0.181; p < 0.001). A negative correlation was observed between disease severity and oxyhemoglobin variation (rho = −0.420; p = 0.041), with no other significant associations. In conclusion, ACE exercise is well tolerated and capable of improving muscle oxygenation, even in limbs affected by PAD.