Hypertension after liver transplantation: A predictive role for pretreatment hemodynamics and effects of isradipine on the systemic and renal circulations

Abstract

Hypertension developing after liver transplantation during immunosuppression with cyclosporine A reflects an unusual hemodynamic transition from peripheral vasodilation to systemic and renal vasoconstriction. Although dihydropyridine calcium channel blockers are often administered for their efficacy in promoting vasodilation, some liver transplant recipients report marked symptomatic intolerance to these agents. In the present study we examined systemic and renal responses to isradipine using systemic (thoracic bioimpedance) and renal hemodynamic measurements in 15 liver transplant recipients studied at the time of initial diagnosis of posttransplant hypertension and after 3 months of treatment. Circadian blood pressure patterns were examined by overnight ambulatory blood pressure monitoring before and during antihypertensive therapy. During isradipine administration, blood pressure decreased from 151 ± 3/91 ± 2 to 130 ± 3/81 ± 2 mm Hg ( P < .01) without change in renal blood flow (406 ± 43 to 425 ± 52 mL/min/1.73m 2, P = NS) or renal vascular resistance index (25,674 ± 3312 to 20,520 ± 2311 dynes · sec · cm −5/m 2, P = NS). Pre-treatment differences in systemic vascular tone persisted during treatment and predicted the tendency for symptomatic tachycardia and flushing, predominantly in those with hyperdynamic circulations. Twice daily dosing of isradipine was associated with partial and significant restoration of the nocturnal decrease in blood pressure (systolic blood pressure decreased 5.5%, normal 13%), usually absent early after transplantation. Our results demonstrate the ability of hemodynamic measurements to predict the symptomatic response to antihypertensive therapy in the posttransplant setting.