The relation of plasma renin activity to left ventricular hypertrophy and retinopathy in patients with arterial hypertension.

Abstract

Abstract. Plasma renin activity (PRA) has been determined in 72 hypertensive patients in the supine position at 8 a.m. after 48 hours' sodium restriction. Mean PRA was highest in patients with renal disease, but individual values overlapped with those from the 51 patients with “essential” hypertension. Ten patients were found to have low and unresponsive PRA (≤0.4 ng ang. I/ml/h); primary aldosteronism was diagnosed and verified by operation in 3 of them. After exclusion of patients with renal disease we found in the remainder, 54 patients, that the presence of left ventricular hypertrophy (LVH) was associated with a higher mean PRA than in patients without LVH. The relative frequency of LVH was, however, higher in the 10 patients with low, unresponsive PRA (50%) than in patients with normal or high PRA (43.3%). LVH was most closely related to the BP level, especially the systolic BP which was significantly higher in patients with LVH than in those without. It is concluded that the level of the BP is the single most important factor for the development of LVH, while renin‐angiotensin are probably of no direct importance. The patients were divided into two groups according to the severity of retinal changes. The relative frequency of the most advanced retinopathy (grades II and III after Keith and Wagener) was, unlike the occurrence of LVH, found to be lower in patients with low PRA, occurring in 1 of 10 patients as opposed to 12 of 44 patients with normal or high PRA. Presence of retinopathy grade II—III in patients with normal/high PRA was associated with a significantly higher mean PRA, than in patients with grade 0–1 changes. Patients with retinopathy grade II—III were not older, their hypertension had not been known for a longer time, but they had significantly higher systolic and diastolic BP than patients with retinopathy grade 0–1. Renin‐angiotensin may play a direct role for the development of retinal hypertensive arteriolopathy. The close association between a high mean PRA and BP in the patients with the most advanced retinopathy could mean that angiotensin increases the adverse effect of high BP on arteriolar walls.