Might type A acute dissection repair with the addition of a frozen elephant trunk improve long-term survival compared to standard repair?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: in patients with an acute type A dissection (TAAD) is a frozen elephant trunk in addition to standard aortic dissection repair advantageous in terms of improved long-term mortality and closure of the distal false lumen? Altogether more than 138 papers were found using the reported search, of which six represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Jakob et al. (23 patients stented vs. 22 patients non-stented), showed similar early outcome but lower false lumen patency rate and lower need of reintervention in the stented group. Pochettino et al. (36 patients stented vs. 42 patients non-stented) reported higher circulatory arrest time and higher incidence of spinal cord and bowel ischemia but a lower false lumen patency rate in stented group. Uchida and co-workers (65 patients stented vs. 55 patients non-stented) reported similar early outcome but better long-term survival and freedom from aortic events in the stented group. Consecutively, Uchida et al. reported the follow-up of the stented group demonstring false lumen thrombosis in all patients one month postoperatively, and complete after three years. Sun and co-workers (107 patients operated with an hybrid approach) showed a hospital mortality of 4.67% and neurological complications rate of 5.6%. At follow-up (35+/-14 months), 95% of the patients had false lumen thrombosis and no distal reoperations were needed. We conclude that the frozen elephant trunk is still rarely adopted during TAAD repair. However, this procedure can be performed safely without increase the operative mortality and morbidity but with an overall higher cardiopulmonary bypass and circulatory arrest time. Spinal cord ischemia and malperfusion syndrome represents the main complications associated with this procedure. Despite few studies, this procedure seems to allow early thrombosis of the false lumen and a reduction of late thoraco-abdominal aneurysm formation and reoperations rate.