Outcomes of Left Heart Bypass Versus Circulatory Arrest in Elective Open Surgical Descending and Thoraco-abdominal Aortic Repair.

OBJECTIVES: To compare early (30 day mortality and major complications) and midterm (survival) outcomes in elective open surgical descending and thoraco-abdominal aortic repair using left heart bypass (LHB) versus hypothermic circulatory arrest (HCA) for organ protection, hypothesising non-inferiority of HCA management. METHOD: This was a retrospective clinical cohort study with cross sectional follow-up. All elective (n = 90) descending or thoraco-abdominal aortic repairs performed between 2004 and 2015 using either LHB (n = 57) or HCA (n = 33) were included. Pre- and intra-operative variables were evaluated by univariate statistical analysis. Thirty day and follow-up mortality were primary endpoints; major complications were secondary endpoints. Propensity score matching was employed to adjust for selection bias. Kaplan-Meier methods were used to estimate midterm survival. RESULTS: Overall 30 day mortality was 8/90 (8.9%): 6/57 (10.5%) using LHB vs. 2/33 (6.1%) using HCA, p = .47. Five patients (5.6%) suffered paraplegia: 3/57 (5.3%) using LHB vs. 2/33 (6.1%) using HCA, p = .87. Stroke occurred in 6/57 (11%) vs. 2/33 (6.1%), p = .76; renal failure in 27/57 (47%) vs. 19/33 (58%), p = .90; and respiratory failure in 17/57 (30%) vs. 11/33 (33%), p = .68. In 26 propensity score matched pairs, findings remained unaltered. Total follow-up was 443 patient years (median 4.9 years). Estimated survival was 78% at 1 year and 77% at 5 years in LHB vs. 72% and 67%, respectively, with HCA; there were no significant inter-group differences, before or after propensity score matching. CONCLUSIONS: In elective descending or thoraco-abdominal aortic repair, no statistically significant differences in 30 day mortality, major complications, or follow-up survival were found when LHB and HCA were compared. These findings remained after propensity score matching.

Complete myocardial revascularization with left heart bypass without oxygenator on the beating heart.

BACKGROUND: Whereas the complete myocardial revascularization is necessary in high risk group patients, the CABG procedure on the beating heart on circumflex artery still presents a dilemma. METHODS: Between January 1994 and September 1996, we performed complete myocardial revascularization with left heart bypass in 62 patients (54 male, 8 female, mean age: 57) who had absolute or relative contraindications for CPB. RESULTS: The hospital mortality was 3.2%, late mortality was 1.6%. Peroperative MI was seen in 2 patients (3.2%). The mean number of distal anastomosis was 3.6 (ranged 2-6). CONCLUSION: Complete myocardial revascularization on the beating heart can be performed by using left heart bypass (LHBP) without using an oxygenerator safely in high risk patients.

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 bypass in thoracoabdominal aortic aneurysm surgery. Data from 50 patients 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 centrifugal pump (without systemic heparinization) was used. Patient-, disease-, and operation-related variables were analyzed using univariate methods. There were no intraoperative deaths. The in-hospital mortality rate 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 five (10%) patients and paraplegia in five (10%). Sixteen (32%) patients had respiratory insufficiency requiring prolonged (> 8 days) ventilation. After univariate analysis, the risk factors for developing a need for postoperative dialysis were found to be the preoperative creatinine level (p = 0.002) and the presence of preoperative arterial hypertension (p = 0.018). A history of peripheral vascular occlusive disease (p = 0.008) was an important risk factor for predicting late death. No factors retained significance in the univariate analysis of hospital deaths and postoperative paraplegia. Renal and spinal ischemic times were substantially reduced in comparison to the theoretic times calculated if cross-clamping had been used. Bypass-related complications were completely absent. The use of a left heart bypass during thoracoabdominal aortic aneurysm surgery may not reduce the global complication rate; the results were similar to those achieved using simple cross-clamping. However, this technique appears to be the method of choice for protecting organ systems at risk during difficult repairs.