Differential outcomes of open and clamp-on distal anastomosis techniques in acute type A aortic dissection

OBJECTIVES: Open-distal anastomosis is the preferred technique over clamp-on technique for surgical repair of acute type A aortic dissection (ATAAD). The aim of this study was to define how outcomes of ATAAD were affected by the use of either technique.

METHODS: Nordic Consortium for Acute Type A Aortic Dissection includes 8 academic cardiothoracic hospitals in 4 Nordic countries. The cohort consisted of 1134 patients, 153 clamp-on and 981 open-distal, from 2005 to 2014.

RESULTS: Patients who underwent operation with the clamp-on were younger, more frequently had coronary artery disease, bicuspid aortic valve, hypotension/shock or syncope, and a greater PennClass than open-distal patients. Postoperative cerebral vascular accident occurred less frequently in clamp-on (14/153, 10%) compared with the open-distal group (190/981, 20%). Clamp-on had greater 30-day mortality (39/153, 25%) than the open-distal group (158/981, 16%), and 5-year survival was also worse in clamp-on (61.8% ± 4.4%) compared with the open-distal group (73.0% ± 1.6%). The open-distal technique was used more frequently in greater-volume hospitals but was not independently associated with 30-day mortality. Preoperative condition was an independent risk factor whereas hospital volume and later year of operation were beneficial in regard to short-term outcome. Open-distal was independently associated with improved mid-term survival.

CONCLUSIONS: Patients who underwent operation with the clamp-on were sicker on presentation and had worse short- and mid-term survival compared with the open-distal group. Patients in the open-distal group had greater rates of cerebrovascular complications. The results support the routine use of open-distal anastomosis as the primary operative strategy for ATAAD, although clamp-on can be performed successfully in select cases.