Physical Activity and Improved Diastolic Function in Spinal Cord–Injured Subjects

Abstract

Subjects with spinal cord injury (SCI) have been reported to present impaired left ventricular (LV) diastolic function in comparison with able-bodied (AB) ones. The present study investigated the effect of regular physical activity on the cardiac structure and function of SCI subjects. Fifty-eight SCI men (29 sedentary [SCI-S] and 29 athletes [SCI-A]) and 29 AB men were cross-sectionally evaluated by clinical, laboratory, hemodynamic, and echocardiographic analysis. All enrolled subjects were normotensive, nondiabetic, nonsmoker, and normolipemic, and the studied groups presented similar age and body mass index. SCI-S presented similar LV structural and systolic parameters but higher E/Em (8.0 ± 0.5) and lower Em/Am (1.18 ± 0.09) ratios than SCI-A and AB (E/Em = 6.4 ± 0.3 and 5.9 ± 0.3, respectively; Em/Am = 1.57 ± 0.12 and 1.63 ± 0.08, respectively; all P < 0.05 compared with SCI-S). Analysis of SCI individuals according to injury level revealed that tetraplegic athletes had similar features compared with sedentary tetraplegic subjects, except for higher Em (10.9 ± 0.6 vs 8.6 ± 0.7 cm s, P < 0.05) and lower E/Em ratio (6.3 ± 0.4 vs 8.8 ± 0.8, P < 0.05), whereas paraplegic athletes had similar features compared with sedentary paraplegic individuals, except for higher LV end-diastolic diameter (49.4 ± 1.4 vs 45.0 ± 1.0 mm, P < 0.05) and Em/Am ratio (1.69 ± 0.20 vs 1.19 ± 0.08, P < 0.05) and lower LV relative wall thickness (0.330 ± 0.012 vs 0.369 ± 0.010, P < 0.05) and heart rate (67.1 ± 4.2 vs 81.9 ± 2.8 bpm, P < 0.05). Regular physical activity is associated with improved LV diastolic function in SCI subjects and might exert distinct cardiac structural effects in tetraplegic and paraplegic subjects.