Aortic Hemiarch Replacement: The 7-Minute Technique
This video demonstrates an efficient method for aortic hemiarch replacement termed the seven-minute technique.
Elective aortic hemiarch replacement under hypothermic circulatory arrest is commonly performed for ascending aortic aneurysms with proximal aortic arch involvement. In general, the hypothermic circulatory arrest times in these cases are between eighteen and twenty minutes. With the seven-minute technique, the operation is simplified, and efficiency is maximized, which reduces steps and circulatory arrest times.
The following surgical examples involve two cases. The first patient is a seventy-one-year-old man with aortic root, ascending aortic, and proximal aortic arch aneurysms, as well as aortic and mitral regurgitation. The patient’s CTA showed aortic diameters of 5.2 cm for the root, 4.8 cm for the ascending aorta, and 4.1 cm for the proximal arch.
The second case is a sixty-eight-year-old man with prior aortic valve replacement because of a bicuspid aortic valve. He presented with an aortic root, ascending aortic, and proximal aortic arch aneurysms, as well as mitral regurgitation. The patient’s CTA showed aortic diameters of 4.5 cm for the root, 5.9 cm for the ascending aorta, and 4.2 cm for the proximal arch
The imaging for case number one showed the large aortic root aneurysm that tapered at the aortic arch, whereas the imaging for case number two showed a large ascending aortic aneurysm that also involved the root and the proximal arch.
Intraoperative findings for both cases confirmed aortic aneurysms that both tapered at the proximal arch.
In case number one, the cross-clamp was removed and blood flow ceased as cardiopulmonary bypass was discontinued. The proximal aortic arch was then resected. A 30 mm graft was brought to the field, and the arch anastomosis was initiated with a 4-0 SH Prolene suture.
Deep bites were taken on the aorta, and there was moderate lateral travel, which focuses on equal spacing. Perfect hemostasis is noted with this technique, and there was no need for repair sutures. The intraoperative findings matched the preoperative imaging, which showed the aneurysm tapering nicely at the aortic arch.
In case number two, the cross-clamp was again removed and circulatory arrest initiated. The proximal arch was resected and the seven-minute technique was started, just as in case number one. Excellent hemostasis was noted afterward, with no repair sutures. Circulatory arrest times remained constant, despite the differences in the overall operations.
Considerations for the seven-minute technique include, firstly, the aortic cannula location, which should be placed in the distal arch, just inferior to the left carotid and left subclavian arteries. This allows for a hemiarch resection in which the aortic cannula can remain in place, reducing a few time-consuming steps. For the graft to arch anastomosis, the starting position is 4:00, heading clockwise to 10:00, then switching suture arms and going counterclockwise from 4:00 to 10:00.
Deep bites on the aorta and a moderate lateral travel distance with equal spacing are crucial to anastomotic integrity and hemostasis. During the seven-minute technique, no felt strips are necessary because of the large bites on the aorta.
Additionally, with the body cooled to between 26 and 28 degrees Celsius, there is very low risk for neurologic dysfunction with only seven minutes of circulatory arrest. Therefore, antegrade cerebral perfusion is not warranted.
In addition, a significant amount of time is saved by avoiding both the felt strips and direct placement of the antegrade cerebral perfusion catheter.
Gambardella, Ivancarmine, et al. "Contemporary results of hemiarch replacement." European Journal of Cardio-Thoracic Surgery 52.2 (2017): 333-338.