USE OF LEFT-HEART BYPASS IN THE SURGICAL REPAIR OF THORACOABDOMINAL AORTIC-ANEURYSMS

The purpose of this study was to assess the usefulness of left heart b ypass in thoracoabdominal aortic aneurysm surgery. Data from 50 patien ts who underwent thoracoabdominal aortic aneurysm repair between July 1987 and October 1993 were retrospectively reviewed. In all of them a left heart bypass (left atrium to left femoral artery) with a centrifu gal pump (without systemic heparinization) was used. Patient-, disease -, and operation-related variables were analyzed using univariate meth ods. There were no intraoperative deaths. The in-hospital mortality ra te was 8% (n = 4). Survival rates were 77% (+/-6.5) at 2 years and 62% (+/-8.7) at 5 years. Renal failure requiring dialysis occurred in fiv e (10%) patients and paraplegia in five (10%). Sixteen (32%) patients had respiratory insufficiency requiring prolonged (>8 days) ventilatio n. After univariate analysis, the risk factors for developing a need f or postoperative dialysis were found to be the preoperative creatinine level (p = 0.002) and the presence of preoperative arterial hypertens ion (p = 0.018). A history of peripheral vascular occlusive disease (p = 0.008) was an important risk factor for predicting late death. No f actors retained significance in the univariate analysis of hospital de aths and postoperative paraplegia. Penal and spinal ischemic times wer e substantially reduced in comparison to the theoretic times calculate d if cross-clamping had been used. Bypass-related complications were c ompletely absent. The use of a left heart bypass during thoracoabdomin al aortic aneurysm surgery may not reduce the global complication rate ; the results were similar to those achieved using simple cross-clampi ng. However, this technique appears to be the method of choice for pro tecting organ systems at risk during difficult repairs.