Objectives: To study candidates for liver transplant before and 6 weeks after transplant, and to elucidate the role of endothelial dysfunction and plasma endothelin concentrations in the development of hypertension. DESIGN PROSPECTIVE: follow-up study.
Setting: Institutional, outpatient.
Patients: and controls Fifteen patients (11 men, four women, mean age 46.7+/-13.2 years) with end-stage liver disease (ESLD) and healthy volunteers of comparable age and sex.
Methods: We performed office blood pressure readings and 24 h ambulatory blood pressure monitoring (ABPM), measurements of endothelial-dependent vasodilatation using high-resolution ultrasound in the brachial artery at rest and during reactive hyperemia, and plasma endothelin-1 assays 3 months before and 6 weeks after the transplant.
Results: Office systolic and diastolic blood pressures increased significantly 6 weeks after liver transplantation (from 116.6+/-14.1 to 139.9+/-19.5 mmHg and from 68.6+/-9.5 to 84.1+/-9.8 mmHg, respectively; both P < 0.001). Hypertension based on office blood pressure readings increased from 6.7 to 40% (P < 0.05). Mean 24 h systolic blood pressure increased from 118.7+/-10.3 to 140.0+/-19.0 mmHg (P < 0.001), mean 24 h diastolic blood pressure increased from 86.0+/-7.7 to 104.8+/-13.9 mmHg (P < 0.001) and heart rate increased from 74.8+/-10.2 to 80.2+/-8.2 beats/min (P < 0.05). Brachial artery flow-mediated dilatation did not change throughout the study (before transplant: 4.2+/-4.0%; after transplant: 6.3+/-5.4%; NS) and did not differ from that in controls (5.2+/-3.8%). Plasma endothelin-1 was increased in patients with ESLD (15.3+/-2.6 pg/ml) compared with controls (5.6+/-0.4 pg/ ml; P < 0.001) and remained unchanged 6 weeks after liver transplantation (14.1+/-3.7 pg/ml).
Conclusion: Our results show increased blood pressure with suppressed circadian blood pressure variability in liver graft recipients 6 weeks after transplant and no change in endothelial function and plasma endothelin concentrations. Therefore, the blood pressure increase documented in our study cannot be explained by endothelial dysfunction. Twenty-four hour ABPM should be performed routinely in patients who have undergone liver transplant.