Changing from supine to sitting posture in cardiac transplant recipients resulted in a 15% reduction in stroke index, whereas passive leg elevation in the supine posture increased it by 9% (p<0.001).
Observational (n=40)
How do central hemodynamics differ during upright versus supine exercise in orthotopic cardiac transplant recipients?
In cardiac transplant recipients, assuming an upright posture significantly decreases stroke index and cardiac index compared to the supine posture, highlighting important postural hemodynamic differences.
Absolute Event Rate: -15% vs 9%
p-value: p=<0.001
Abnormal hemodynamic responses during supine exercise have been well documented in orthotopic cardiac transplant recipients. To determine the effect of posture, central hemodynamics were studied in 20 patients during a change from supine to sitting and during graded upright bicycle exercise (group U) and were compared with those of 20 patients matched for age, gender and time from transplantation who were studied after passive leg elevation and during exercise in the supine posture (group S). Passive leg elevation resulted in a 9% increase in stroke index (34 +/- 6 to 37 +/- 6 ml/m2, p less than 0.001) and a 10% increase in cardiac index (3.1 +/- 0.4 to 3.4 +/- 0.5 liters/min per m2, p less than 0.001) in group S patients compared with a 15% reduction in stroke index (34 +/- 7 to 29 +/- 6 ml/m2, p less than 0.001) and a 9% decrease in cardiac index (3.2 +/- 0.6 to 2.9 +/- 0.5 liters/min per m2, p less than 0.001) in group U patients on assuming the sitting posture. Likewise, both the pulmonary capillary wedge pressure and right atrial pressure increased significantly (13 +/- 4 to 17 +/- 8 mm Hg, p less than 0.001 and 5 +/- 3 to 7 +/- 3 mm Hg, p less than 0.001) with passive leg elevation in group S and decreased on sitting (12 +/- 6 to 8 +/- 5 mm Hg, p less than 0.001 and 5 +/- 3 to 3 +/- 2, p less than 0.001) in group U.(ABSTRACT TRUNCATED AT 250 WORDS)
Rudas et al. (Thu,) conducted a observational in Orthotopic cardiac transplantation (n=40). Upright posture (supine to sitting) vs. Supine posture (passive leg elevation) was evaluated on Change in stroke index upon posture change (p=<0.001). Changing from supine to sitting posture in cardiac transplant recipients resulted in a 15% reduction in stroke index, whereas passive leg elevation in the supine posture increased it by 9% (p<0.001).