Editorial comment for ‘Safety and efficacy of ascending aorta cannulation during repair of acute type A aortic dissection’

Abstract

I read the article by Osumi et al. with great interest. The authors investigated the results of surgery on 52 patients with acute type A aortic dissection (AAAD). In this study, they discussed the central cannulation technique which had been accepted in several institutions in recent years. The central cannulation group showed shorter operation time, shorter cardiopulmonary bypass (CPB) time and lower mortality rate than the peripheral group. They concluded that the central cannulation technique for AAAD was more rapid and safer compared with the peripheral cannulation technique. Lijoi has reported, for the first time, this technique in 1998 [1]. Subsequently, Minatoya [2], Noiseuxa [3] and Yamada [4] have reported this technique. In addition, Jakob [5] has introduced the aggressive direct cannulation technique in 2007. Although there are a wide variety of central cannulation techniques, most institutions use the Seldinger technique under ultrasound guidance. Our institution [6, 7] also uses the similar technique to that reported by the authors. I can understand that the mean operation time and the interval time between the start of operation and the start of CPB were shorter, but I wonder about lower mortality and morbidity in the central cannulation approach [8, 9]. I think that the patient selection and the small number of patient cohort may have led to these results. The best site of cannulation for AAAD still remains controversial. We need further large-scale multicenter randomized control trials. While we have utilized the central cannulation technique in many cases since 1999, we have alternatively selected axillary artery (AXA), femoral artery (FA) and apex of left ventricle (LV apex) on a case by case basis. We have the central cannulation approach for all cases of AAAD since 2007. If impossible, we converted other sites (e.g. AXA, FA and LV apex). One hundred thirty consecutive patients underwent prosthetic graft replacement of the ascending aorta or aortic arch for AAAD between 2007 and 2012. The mean age of patients with AAAD was 68 years. The male/female proportion was approximately even. The success rate of the central cannulation approach was 94 % (122/130). We could not establish CPB by the central cannulation approach in eight patients. The alternative cannulation sites were FA (2 cases), AXA (3 cases) and LV apex (3 cases). We classified failed cases into four groups based on the reasons: (1) Inadequate perfusion flow (2 cases), (2) Collapse of the true lumen (2 cases), (3) Collapse of the ascending aorta due to massive bleeding or cardiac arrest (3 cases) and (4) Complete disjunction of the aortic intima (1 case). I did not know the cause of inadequate perfusion flow in details. We suppose that the cannula may have moved to the false lumen. Collapse of the true lumen is not rare in AAAD. Although we can perform central cannuation successfully even in the presence of collapse of the true lumen, it was impossible in two cases. We have done This comment refers to the article available at doi:10.1007/s11748013-0355-9.