Moderate hypothermia ≥24 and ≤28°C with hypothermic circulatory arrest for proximal aortic operations in patients with previous cardiac surgery.

OBJECTIVES: To determine whether, in patients with previous cardiac operations, moderate hypothermia (between 24 and 28°C) for hypothermic circulatory arrest (HCA) during antegrade cerebral perfusion (ACP) is safe for use during surgery on the proximal aorta and transverse aortic arch. METHODS: Over a 7-year period, 118 patients underwent ascending aortic and hemiarch repair (n = 70; 59.3%), total arch replacement (n = 47; 39.8%) or ascending aortic replacement to treat porcelain aorta (n = 1; 0.9%). Simultaneous procedures included aortic root repair or replacement (n = 33; 28.0%) and coronary artery bypass grafting (n = 21; 17.8%). All patients had previously undergone cardiac operations via a median sternotomy. Eighteen patients (15.3%) had more than 1 previous sternotomy, and 24 patients (20.3%) required emergent/urgent operation. Median cardiopulmonary bypass, cardiac ischaemic, circulatory arrest and ACP times (min) were 136.0 [118-180 interquartile range (IQR)], 91.0 (68-119 IQR), 34.0 (21-59 IQR) and 33.5 (20-59 IQR), respectively. The median temperature when HCA was initiated was 24.2°C (24.1-24.8°C IQR). RESULTS: The operative mortality rate was 10.2% (n = 12). Six patients (5.1%) had a permanent stroke, and 16 patients (13.6%) had a composite adverse outcome (operative mortality and/or a permanent neurological event and/or permanent haemodialysis at discharge). Preoperative renal disease was significantly more prevalent (P= 0.020) and the median circulatory arrest time significantly longer (48.5 vs 33 min; P= 0.058) in patients with composite adverse outcomes. Multivariable analysis of the redo patients showed that age (P =0.025), preoperative renal disease (P =0.024) and ACP time (P =0.012) were independent risk factors for a new postoperative renal injury. CONCLUSIONS: Moderate hypothermia for HCA during ACP is being used with increasing frequency, but has not been thoroughly evaluated in patients undergoing cardiovascular reoperations. Our experience suggests that in patients with previous cardiac surgery who are undergoing hemiarch and total aortic arch operations, moderate hypothermia is safe and produces respectable results.

Total aortic arch replacement: A comparative study of zone 0 hybrid arch exclusion versus traditional open repair.

OBJECTIVE: We attempted to identify predictors of adverse outcomes after traditional open and hybrid zone 0 total aortic arch replacement. METHODS: We performed multivariable analysis using 16 variables to identify predictors of adverse outcomes (mortality, permanent neurologic events, and permanent renal failure necessitating hemodialysis) in 319 consecutive patients who underwent total aortic arch replacement in the past 8.5 years and a subgroup analysis in 25 propensity-matched pairs. A total of 274 patients (85.9%) had traditional open repair, and 45 patients (14.1%) had hybrid zone 0 total arch exclusion. RESULTS: Operative mortality was 10.3% (n = 33): 11.1% (n = 5) in the hybrid group and 10.2% (n = 28) in the traditional group (P = .79). A total of 19 patients (5.9%) had permanent stroke (15 traditional [5.5%] vs 4 hybrid [8.9%]; P = .32), and 2 patients (both traditional) had permanent paraplegia (P = 1.00). The hybrid group had more total neurologic events (P = .051) but not more permanent strokes (P = .32). Prior cardiac disease unrelated to the aorta (P = .0033) and congestive heart failure (P = .0053) independently predicted permanent adverse outcome (operative mortality, permanent neurologic event, or permanent renal failure). Concomitant coronary artery bypass grafting independently predicted permanent stroke (P = .032), as did previous cerebrovascular disease (P = .032). In multivariable analysis, procedure type (hybrid or traditional) was not an independent predictor of stroke (P = .09). During a median follow-up of 4.5 years (95% confidence interval, 3.9-4.9), survival was 78.7%, with no intergroup difference (P = .14). CONCLUSIONS: Among contemporary cases, both traditional and hybrid total aortic arch replacement had acceptable results. Comparing these 2 different surgical treatment options is challenging, and an individualized approach offers the best results. Permanent adverse outcome was not significantly different between the 2 groups. Procedure type is not an independent predictor of permanent stroke. Prior cardiac disease, past or current smoking, and congestive heart failure predict adverse outcomes for total aortic arch replacement.

Innominate artery cannulation for proximal aortic surgery: outcomes and neurological events in 263 patients.

OBJECTIVES: To determine whether innominate artery cannulation is the ideal perfusion strategy for delivering antegrade cerebral perfusion (ACP) during surgery on the proximal ascending aorta and transverse aortic arch. METHODS: A total of 263 patients underwent innominate artery cannulation with a side graft for surgery on the proximal aorta. Operations performed were ascending and proximal arch replacement (n = 213, 81.0%), ascending and total arch replacement (n = 33, 12.6%) and ascending aortic replacement (n = 12, 4.6%). Concomitant or other procedures included aortic root replacement and repair (n = 113, 43.0%), aortic valve replacement or repair (n = 118, 44.9%), coronary artery bypass (n = 40, 15.2%), antegrade stent graft delivery to the proximal descending thoracic aorta for aneurysm or dissection (n = 28, 10.7%), mitral valve repair (n = 11, 4.2%), patent foramen ovale repair (n = 3, 1.1%) and tricuspid valve repair (n = 2, 0.8%). Twenty-seven patients (10.3%) presented with acute or subacute Type I aortic dissection, and 45 (17.1%) had a previous sternotomy. Median cardiopulmonary bypass (CPB), cardiac ischaemia and ACP times were 126.0 [95-163 interquartile range (IQR)], 91.0 (73-121 IQR) and 21.0 (16-32 IQR) min. Bilateral ACP was delivered in 235 patients (90.7%). RESULTS: The operative mortality rate was 4.9% (n = 13). Nine patients (3.4%) had postoperative stroke, which was permanent in 5 (1.9%) of them. Multivariate analysis associated risk of stroke or temporary neurological deficit with acute or subacute Type I aortic dissection (P = 0.028) and age (P = 0.015). Renal disease (P = 0.036) and CPB time (P = 0.011) were independent risk factors for operative mortality. Circulatory arrest time was identified as a risk factor for mortality (P = 0.038). CONCLUSIONS: Innominate artery cannulation can be performed safely and poses a low risk of neurological events in procedures requiring hypothermic circulatory arrest. The technique for cannulating this artery should be part of the routine armamentarium of cardiac and aortic surgeons, and the innominate artery is among the preferred perfusion sites for delivering ACP.

Nationwide trends and regional/hospital variations in open versus endovascular repair of thoracoabdominal aortic aneurysms.

OBJECTIVES: Thoracic endovascular aortic repair (TEVAR) has been gaining popularity for the treatment of thoracoabdominal aortic aneurysm (TAAA). We used a nonvoluntary database to examine national trends and regional/hospital variations in the use of TEVAR and open thoracic aortic repair (OTAR) for TAAA. METHODS: From the 2005-2008 Nationwide Inpatient Sample database, we identified all patients with the diagnosis of TAAA who were treated with TEVAR or OTAR. Rates of these procedures were compared between years, across geographic regions, and between hospitals of various bed sizes. RESULTS: Over the study period, the rate of OTAR remained relatively stable (range, 7.5/100 patients in 2005 to 10.1/100 patients in 2008; P = .26), whereas the rate of TEVAR increased dramatically (range, 1.4/100 patients in 2005 to 6.3/100 patients in 2008; P < .0001). In 2008, 29% (211) of all TEVAR procedures and 11% (130) of all OTAR procedures were performed in western regions of the United States (P = .03). Additionally, 13% (95) of all TEVAR procedures and 3% (35) of all OTAR procedures were performed in smaller hospitals (P < .0001). CONCLUSIONS: The use of TEVAR for TAAA repair increased significantly over the study period, whereas OTAR rates remained relatively stable. Our findings suggest that more patients who were otherwise not surgical candidates or did not have traditional surgical indications for OTAR were treated with TEVAR, most commonly in regions or hospitals where OTAR is less often performed. Given the complexity of TAAA cases, these results may have significant implications for patient safety in the current era of heightened health care scrutiny.