Abstract
The aim of this study was to investigate the behaviour of circulating ET‐1 in patients with carotid atherosclerosis, before and after carotid thromboendarterectomy (TEA), to test the hypothesis that plasma ET‐1 decreases after removal of atherosclerotic lesion. Plasma immunoreactive ET‐1 levels were determined in 17 patients with symptomatic and/or hemodynamically significant carotid atherosclerosis on the day before TEA, 48 h and 72 h after surgery and, in 11 of them, also after 8 h and 24 h. Compared to controls, ET‐1 levels were significantly higher both before and after TEA; after carotid revascularisation (8 h) ET‐1 increased; then, from the 24th h, ET‐1 gradually decreased and at the 48th h and 72th h the decrease was significant in front of basal values. The increase of plasma ET‐1 in the acute postoperative phase may reflect the degree of surgical stress and manipulation in diseased blood vessels; the following decrease may indicate the improvement of vascular dysfunction in the involved carotid site; the persistence of high ET‐1 levels 72 h after surgery could suggest the presence of residual ischemia in the involved district and/or the involvement of other sites in ET‐1 production.