Modulation of left ventricular diastolic filling during exercise in persons with cervical motor incomplete spinal cord injury

• Published in: European journal of applied physiology Vol. 119; no. 11-12; pp. 2435 - 2447
• Main Authors: Aldhahi, Monira I., Guccione, Andrew A., Chin, Lisa M. K., Woolstenhulme, Joshua, Keyser, Randall E.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2019; Springer Nature B.V
• Subjects: Adolescent; Adult; Aged; Biomedical and Life Sciences; Biomedicine; Cardiac Output - physiology; Cross-Sectional Studies; Diastole - physiology; Exercise - physiology; Exercise Test - methods; Exercise Therapy - methods; Exercise Tolerance - physiology; Female; Heart; Heart - physiopathology; Heart Ventricles - physiopathology; Human Physiology; Humans; Male; Middle Aged; Occupational Medicine/Industrial Medicine; Original Article; Skeletal muscle; Spinal cord injuries; Spinal Cord Injuries - physiopathology; Sports Medicine; Stroke Volume - physiology; Ventricle; Ventricular Function, Left - physiology; Young Adult; Diastolic function; Cardiac preload; Cardiac filling ratio; Exercise; Spinal cord injury; Stroke volume
• ISSN: 1439-6319; 1439-6327; 1439-6327
• DOI: 10.1007/s00421-019-04249-9

Purpose To characterize left ventricular diastolic function during an exertional challenge in adults with incomplete cervical spinal cord Injury (icSCI). Methods In this cross-sectional study, a two-group convenience sample was used to compare left ventricular LV diastolic performance during a 5–10 W·min −1 incremental arm ergometer exercise protocol, using bioimpedance cardiography. Subjects were eight males with cervical incomplete spinal cord injury (icSCI; C5-C7: age 39 ± 14 years) versus eight able-bodied males (CON: age 38 ± 13 years). Left ventricular (LV) diastolic indices included end-diastolic volume (EDV) and early diastolic filling ratio (EDFR). LV ejection time (LVET), inotropic index (d Z /d T 2 ) and stroke volume (SV) were compared between the groups at peak exercise, and maximum workload for the icSCI group (isomax). Results EDV (at peak exercise:131.4 ± 7.3 vs 188.78 ± 9.4, p  < 0.001; at isomax: 131.4 ± 7.3 vs 169 ± 23, p  = 0.0009) and EDFR (at peak exercise 73 ± 14% vs 119 ± 11%, p  = 0.006; at isomax 94 ± 10; p  = 0.009) were significantly reduced in icSCI compared to CON, respectively. Significant differences in LVET (icSCI: 273 ± 48 vs CON: 305 ± 68; p  = 0.1) and d Z /d T 2 (icSCI: 0.64 ± 0.11 vs CON: 0.85 ± 0.31; p  = 0.1) were not observed at isomax, despite a significant decrease in SV in the subjects with icSCI (77.1 ± 6.05 mL vs 105.8 ± 9.2 mL, p  < 0.00) Conclusion Left ventricular filling was impaired in the subjects with icSCI as evidenced at both peak exercise and isomax. It is likely that restrictions on the skeletal muscle pump mechanized the impairment but increased left ventricular wall stiffness could not be excluded as a mediator.