Revascularization of the superior mesenteric artery after acute thromboembolic occlusion

Background: The outcome and prognostic factors after revascularization of acute thromboembolic occlusion of the superior mesenteric artery (SMA) are poorly documented. Methods: Sixty patients with acute thromboembolic occlusion of the SMA had revascularization procedures at 21 hospitals from 1987 to 1998. They were registered prospectively in the Swedish Vascular Registry. Patient files were analysed retrospectively. Results: The median age of the patients was 76 years; 73 per cent suffered from cardiac disease and 23 per cent had previous vascular surgery. Onset of symptoms was classified as sudden (30 per cent), acute (33 per cent) or insidious (37 per cent). The occlusions were thought to be either embolic (67 per cent) or thrombotic (33 per cent). The diagnosis was suspected on first examination in 32 per cent of patients, a group whose median time to operation was shorter (P = 0.01). Fifty-eight patients had an exploratory laparotomy and subsequent revascularization, and two were treated with thrombolysis alone. Second-look laparotomy was performed in 41, and third look in eight patients; 19 required an additional bowel resection. The overall mortality rates were 43, 52, 60 and 67 per cent at 30 days, discharge, 1 and 5 years, respectively. No patient was dependent on intravenous nutrition after 1 year. Previous vascular surgery resulted in a higher institutional mortality rate (79 per cent; P = 0.02). Patients who had a sudden onset of symptoms outside hospital had a better outcome (mortality rate 27 per cent; P = 0.02). Conclusion: Many non-diagnostic radiological examinations were performed and a routine second-look is warranted. The results suggest that attempts at revascularization procedures for acute mesenteric ischaemia may improve the outcome.