Invited commentary

Abstract

In recent years, axillary artery cannulation has gained considerable popularity as a site for arterial perfusion for thoracic aortic surgery, almost to the point of attaching a negative stigma to the use of the femoral artery for this purpose. There is no question that axillary artery cannulation offers significant advantages in specific circumstances, especially when the thoracoabdominal aorta is heavily diseased with mobile atheromatous lesions. In such circumstances, axillary cannulation can avoid the lifting of the aortic “tree bark” that can occur with retrograde femoral perfusion. This article by Lakew and colleagues serves an important role by reminding us that traditional femoral artery cannulation remains an excellent option for many patients. The authors have wisely restricted their analysis to a well-defined and specific group (ie, those patients undergoing surgery only for chronic aortic aneurysm, not dissection). This specificity permits meaningful results by defining a relatively uniform clinical setting for analysis. Also the number of patients is large and the two techniques (ie, femoral and direct aortic cannulation) are carried out simultaneously during the study period, an advantage compared with other comparative studies. The clinical and stroke results achieved in both groups in this study are superb. A weakness of this study is the potential for bias based on the surgeons’ perception of the aortic situation; thus one can safely conclude that femoral cannulation leads to good results in experienced hands. However, it is not safe to conclude that femoral and aortic cannulation are equivalent in all situations, as that would require a prospective, randomized investigation. Another weakness is that the authors did not report or incorporate findings from intraoperative transesophageal echocardiography in their evaluation of potential cannulation sites. In the present era, not using that information represents an anachronism. Another important concept demonstrated by this study is that simple deep hypothermic circulatory arrest with efficient arch surgery produces excellent clinical results with low cerebral complication rates. This point is important to keep in mind vis-à-vis the alternative techniques of retrograde or selective antegrade brain perfusion. The following additional technical observations deserve consideration in selecting cannulation sites for thoracic aortic surgery: •One must not use the femoral artery in cases in which there is intervening iliac or femoral occlusive disease, even moderate in severity. In such situations, forcing the entire pump output retrograde through even a moderate stenosis can precipitate retrograde aortic dissection.•One must avoid femoral cannulation if the intraoperative transesophageal echocardiography shows mobile atheroma in the intervening segment of the aorta.•Also, in cases in which femoral cannulation is initially used and at herosclerotic debris is found on opening and debriding the aorta, the cannula should be moved to the new graft to avoid propelling debris toward the brain.•In descending and thoracoabdominal aortic surgery, one can prevent emboli from reaching the brain by the simple convention of clamping the aorta before perfusion is started and terminating perfusion before the clamp is released. By doing so, wherever potential emboli may go, they are prevented from reaching the brain. Implementation of this measure halved our stroke rate for descending and thoracoabdominal aortic surgery [1Goldstein L.J. Davies R.R. Rizzo J.A. et al.Stroke in surgery of the thoracic aorta incidence, impact, etiology, and prevention.J Thorac Cardiovasc Surg. 2001; 122: 935-945Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar]. The article by Lakew and colleagues complements our recent article that demonstrates the safety and utility of femoral artery cannulation for acute type A aortic dissection [2Fusco D.S. Shaw R.K. Tranqulli M. Kopf G.S. Elefteriades J.A. Femoral cannulation is safe for type A dissection repair.Ann Thorac Surg. 2004; 78: 1285-1289Abstract Full Text Full Text PDF PubMed Scopus (129) Google Scholar]. Thus, between these two articles, the good name of the former gold-standard, femoral cannulation, is to some extent restored to its prior status. Femoral cannulation remains quick, easy, and absent of severe mobile atheromas in the descending and abdominal aortas, it is quite safe for both chronic aneurysm and acute ascending aortic dissection. Femoral Versus Aortic Cannulation for Surgery of Chronic Ascending Aortic AneurysmThe Annals of Thoracic SurgeryVol. 80Issue 1PreviewFemoral artery cannulation and retrograde arterial perfusion have been postulated to increase the risk of cerebral embolism. In this study, the impact of the arterial cannulation site on the perioperative results after proximal aortic surgery is evaluated. Full-Text PDF