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Total aortic arch repair: risk factor analysis and follow-up in 199 patients.

OBJECTIVES
Aortic arch surgery is associated with substantial perioperative risks. New prostheses as well as novel perfusion techniques have been developed to reduce the risks of these procedures. The routine application of these new techniques warrants reassessment of risk factors of aortic arch repair.


METHODS
Between April 2010 and December 2015, 199 patients [61% male, median age 63 years (interquartile range 52-70 years)] underwent total aortic arch repair in our institution. Forty-four per cent of the patients presented with acute aortic dissections (ADs, 32% with malperfusion), 22% with chronic aortic dissections (CDs), 34% with degenerative aneurysms, 24% underwent reoperations. Our surgical technique involved cold blood cardioplegia for cardiac procedures, non-cardioplegic continuous myocardial blood perfusion during aortic arch repair and early lower body reperfusion after distal aortic arch reconstruction. Anastomosis of head vessels is performed at the end of the procedure.


RESULTS
Forty-four per cent of patients underwent aortic root surgery, 90% received a classical elephant trunk (ET) or frozen elephant trunk (FET). Median (interquartile range) cardiopulmonary bypass time, cardiac ischaemia time, hypothermic circulatory arrest time and selective antegrade cerebral perfusion time were 248 min (204-302), 105 min (51-150), 47 min (35-61) and 93 min (72-115), respectively. Operative mortality was 16%, stroke occurred in 10%, dialysis in 21% and spinal cord injury in 5%. Independent risk factors for mortality were age, rethoracotomy for bleeding, postoperative dialysis, maximum lactate value and maximum creatinine kinase-MB (CK-MB) value. 'Beating heart' aortic arch surgery significantly reduced the risk of mortality. Malperfusion syndrome and coronary artery bypass grafting were preoperative predictors of stroke. CD, preoperative renal dysfunction, operation time, rethoracotomy for bleeding and low cardiac output syndrome were risk factors for postoperative dialysis. Freedom from aortic reoperation was 91% (AD), 66% (CD) and 70% (aneurysm) after 2 years.


CONCLUSIONS
Aortic arch repair remains a high-risk procedure, especially in multisegment aortic disease. Several peri- and postoperative factors predicted adverse outcome, indicating the need to further improve perioperative management (e.g. organ protection). Indications for FET treatment have to be thoroughly investigated (e.g. FET in CDs).