Clinical research
Renal vascular response to angiotensin II inhibition in intensive antihypertensive treatment of essential hypertension

Introduction: High blood pressure (BP) leads to target organ damage. It is suggested that regression of early organ lesions is possible on condition of BP normalization. The study objective was to assess whether permanent reduction of BP to the recommended values modifies renal vascular response to acute angiotensin II inhibition in the Doppler captopril test (DCT) in patients with essential hypertension (EH).
Material and methods: Twenty-nine persons (58 kidneys) were found eligible for the study: 18 patients with EH and 11 healthy volunteers constituting the control group. Glomerular filtration rate estimation (eGFR), 24-h ambulatory BP monitoring (ABPM) and DCT with evaluation of renal resistive index change (DRI) were performed before and after a 6-month period of intensive antihypertensive therapy (IAT). Additional ABPM was performed at the end of IAT.
Results: The mean IAT period was 8.5 ±2.4 months. The mean 24-h values of systolic and diastolic BP in the EH group were significantly lower in the IAT period than at the beginning and at the end of the study. Significantly lower systolic and diastolic BP (p < 0.05) and improvement of renal function (eGFR 121 ±38 vs. 139 ±40 ml/min, p < 0.001) were found after IAT as compared to initial values. Before IAT, DRI was significantly lower in the EH group as compared to the controls, but no such differences were found after IAT.
Conclusions: In EH patients, intensive BP lowering to the recommended values was associated with improvement of renal function and normalisation of renal vascular response to acute angiotensin II inhibition.