Hypertension in Heart and Heart-Lung Transplanted Children: Does Impaired Baroreceptor Function Play a Role?

Abstract

Baroreceptor control of beat-to-beat blood pressure in heart and heart-lung-transplanted children is impaired. Time-related trends of baroreceptor function recovery are studied and a possible correlation of baroreflex impairment and systolic hypertension may give evidence for supplemental medical treatment of hypertension. Seventeen patients (six female) 6.1 +/- 3.7 years (range 0.8-13.0 years) after heart (n = 14) and heart-lung (n = 3) transplantation (TX) were studied. Twelve healthy children and 10 children after liver and bone marrow TX taking cyclosporine A (CyA) served as control groups 1 and 2, respectively. Baroreceptor sensitivity (BRS) was calculated from noninvasive systolic beat-to-beat blood pressure (sBP) measurement during a resting phase and a tilt-table test. BRS was significantly impaired in the study group at rest and during tilting; mean sBP was slightly elevated. Significant difference between patients on CyA and healthy controls was not observed. Discrete recovery of BRS occurred after 4 years postTX with decreased sBP (n = 12 pts, BRS 6.78 +/- 7.44 msec/mmHg, sBP 116.2 +/- 12.4 mmHg) when compared to a postTX time course of less than 4 years (n = 5 pts, BRS 4.02 +/- 4.21 msec/mmHg, sBP 122.0 +/- 6.7 mmHg, P = NS). BRS is disturbed after TX in children; four years postTX, a minimal recovery of BRS and a discrete reduction of sBP seem to occur. Those patients with a persistent low BRS and elevated sBP may profit from pharmacological influence in sympathovagal imbalance.