Optimization of aortic arch replacement: two-stage approach.

BACKGROUND: Aneurysms of the aortic arch seldom occur alone. They usually involve the ascending aorta. Occasionally, the aneurysm also involves the descending thoracic or thoracoabdominal aorta. We advocate a staged approach for repair of these extensive aortic aneurysms, with the ascending and arch generally being repaired in the first stage and the descending thoracic or thoracoabdominal aorta being repaired in the second stage. METHODS: Between February 1991 and December 2005, we repaired aneurysms of the ascending, arch, descending thoracic, and thoracoabdominal aorta in 2120 patients. Of these, 254 (12.0%) involved the ascending, arch, and descending aorta (extensive aortic aneurysm). A first-stage repair was done in 254 patients, and 115 returned for a second-stage repair for a total of 369 procedures performed. RESULTS: First-stage 30-day mortality was 6.3% (16/254), with the glomerular filtration rate (GFR) exceeding 70 mL/min in 2.9% of patients and less than 70 mL/min in 10.5% (p < 0.03). Second-stage 30-day mortality was 9.6% (11/115), with GFR exceeding 70 mL/min in 4.9% and less than 70 mL/min in 9.8% (not significant). The incidence of postoperative stroke for the first stage was 2.0% (5/254), and the rate of neurologic deficit (paraplegia and paraparesis) was .9% (1/115) in the second stage. The mortality for the interval of 31 days to 6 weeks after the first-stage operation was 2.9% (7/238). CONCLUSIONS: Aneurysms involving the transverse arch with extensive involvement of the ascending and descending thoracic or thoracoabdominal aorta can be effectively repaired using the two-stage technique with acceptable morbidity and mortality. GFR correlates to surgical outcome in the first-stage repair. After the first stage, prompt treatment of the remaining segment of aorta is crucial to success.

Outcomes of medical management of acute type B aortic dissection.

BACKGROUND: Currently, the optimal treatment of acute type B aortic dissection remains controversial. The purpose of this study was to report early clinical outcomes of medical management for acute type B aortic dissection. METHODS AND RESULTS: Between January 2001 and March 2005, 129 consecutive patients with the confirmed diagnosis of acute type B aortic dissection were studied. Mean age was 61 years (range, 29 to 94), with 33.3% (43/129) female. Acute type B aortic dissection protocol was instituted with the intent to manage all patients medically. Indications for surgical intervention included rupture, aortic expansion, malperfusion, and intractable pain. All patients were followed-up after discharge. Hospital mortality was 10.1% (13/129), 19% (4/21) when vascular intervention was required, and 8.3% (9/108) when medical management was maintained. Early intervention was required in 21 cases (16.2%), 19 (14.7%) open vascular/aortic cases and 2 cases (1.6%) of percutaneous aortic interventions. Morbidity included rupture (4.7%), stroke (4.7%), paraplegia (8.5%), bowel ischemia (7%), acute renal failure (21%), dialysis requirement (13%), and peripheral ischemia (4.7%). Late vascular-related procedures were performed in 5.2% (6/116) of cases. Univariate risk factors for early mortality were rupture (P<0.0001), need for laparotomy (P<0.008), acute renal failure (P<0.0001), need for dialysis (P<0.0001), and lower extremity ischemia (P<0.0004). The only independent risk factors for hospital mortality by multiple logistic regression was rupture (P<0.0009), and independent risk factors for midterm death were history of chronic obstructive pulmonary disease (P<0.002) and low glomerular filtration rate (<57 mL/min; P<0.0001). CONCLUSIONS: Medical management for acute type B aortic dissection is associated acceptable outcomes. Outcomes of other management strategies, eg, endovascular stenting, for acute type B aortic dissection need to be compared with these results.

Evolution of risk for neurologic deficit after descending and thoracoabdominal aortic repair.

BACKGROUND: Cross-clamp time has been reported to correlate with risk of neurologic deficit after thoracoabdominal aortic aneurysm repair. Introduction of cerebrospinal fluid drainage and distal aortic perfusion (adjunct) has greatly reduced the incidence of neurologic deficit. We reevaluated the effect of cross-clamp time before and after introduction of adjunct during a 13-year period. METHODS: Between 1991 and 2004, we repaired 1,106 thoracic and thoracoabdominal aortic aneurysms. Four hundred one patients were female and 705 were male (median age, 67 years). Selective use of adjunct was begun in late 1992, with its routine use by 1993. RESULTS: Aortic cross-clamp times have increased significantly (34 seconds/year; p < 0.0001) since 1991. Despite this increase in cross-clamp time, neurologic deficit rates have declined from the first to the fourth quartile (p < 0.02). This decrease in neurologic deficit is most pronounced with the extent II thoracoabdominal aortic aneurysms (21.1% to 3.3%). The use of the adjunct increased the cross-clamp time by a mean of 12 minutes (p < 0.0001), but was associated with a significant protective effect against neurologic deficit (odds ratio = 0.4; p < 0.0002). Although other previously established risk factors remained significantly associated with neurologic deficit, cross-clamp time is no longer significant. CONCLUSIONS: Adjunct significantly reduced the risk of neurologic deficit, despite increasing cross-clamp time. The use of the adjunct appears to blunt the effect of the cross-clamp time and may provide the surgeon the ability to operate without being hurried. Because cross-clamp time has been effectively eliminated as a risk factor with the use of the adjunct, using this variable to construct risk models becomes irrelevant in our experience.

Glomerular filtration rate is superior to serum creatinine for prediction of mortality after thoracoabdominal aortic surgery.

BACKGROUND: Clinically evident renal disease (dialysis, history of renal insufficiency, or serum creatinine >2.0 mg/dL) is a known risk factor for mortality after thoracoabdominal aortic aneurysm repair. We extended this concept to the questions of whether subclinical renal disease is also a risk factor and how best to identify subclinical disease. We hypothesized that the glomerular filtration rate (GFR) would be a more sensitive determinant of renal function than serum creatinine alone. METHODS: Between 1991 and 2004, we repaired 1106 thoracoabdominal aortic aneurysms and descending thoracic aortic aneurysms. The median age was 67 years. There were 400 (36%) women and 706 (64%) men. We estimated GFR by using the Cockcroft-Gault equation. We divided baseline serum creatinine and baseline GFR into quartiles and estimated the association of the quartiles with 30-day postoperative mortality by chi2 testing. We further subdivided the population into patients with and without clinically evident renal disease and repeated the analysis in the patients without clinically apparent disease (n = 869). RESULTS: Clinically apparent renal disease was highly associated with 30-day mortality (odds ratio, 3.2; P < .0001). In all patients, serum creatinine quartile and GFR quartile were also both highly significantly associated with 30-day mortality (P < .0001). In patients without clinically apparent renal disease, both creatinine and GFR predicted additional mortality, but GFR was a much stronger predictor (P < .02 for creatinine vs < .0001 for GFR). In these patients, mortality ranged from 5% in the best GFR quartile to 27% in the worst. Taken as continuous variables in logistic regression equations, serum creatinine had no discrimination in patients without clinical disease (P = .73), whereas GFR remained strong (P < .0001). CONCLUSIONS: Preoperative renal function is an important determinant of early mortality even in patients without clinically evident disease. Estimated GFR is a much more powerful determinant of mortality risk than serum creatinine alone.