Novel Single-Stage Operation and Inflow Source for Thoracic Aortic Aneurysm and Limb Ischemia

Abstract

Patients with thoracic aortic aneurysms sometimes also have peripheral vascular disease. In such cases, staged operations are usually performed in order to avoid additional morbidity. We have achieved good long-term outcomes in 2 patients with use of a single-stage surgical technique. Our novel procedure uses a pre-sewn side branch with a Dacron graft as the inflow source for the aortofemoral bypass during thoracic aortic aneurysm repair. As of 25 and 52 months' follow-up, these grafts were patent in our 2 patients. We believe that this procedure is a safe and easy single-stage operation that achieves favorable patency. To our knowledge, this is the first report to document the use of a pre-sewn perfusion branch of a Dacron graft as an inflow source for aortofemoral bypass.

It has been reported that 11% of patients with thoracic aortic aneurysms have peripheral vascular disease.¹ In such cases, staged operations are usually performed in order to avoid additional morbidity. However, some patients cannot tolerate laparotomy, or they do not wish to undergo 2 surgical procedures. Herein, we report that 2 patients benefited from our single-stage procedure for revascularization of an ischemic limb during thoracic aneurysm surgery.

Surgical Technique

Patient 1 was a 62-year-old man who had a Stanford type A acute aortic dissection with bilateral lower-limb ischemia due to ascending aortic obstruction by the false lumen. He required emergent surgery. Patient 2 was a 68-year-old man who had an ascending aortic aneurysm, left external iliac artery stenosis, a left ankle–brachial index of 0.66, and symptoms of intermittent claudication.

Thoracic aortic replacement surgery was performed in standard fashion, with each patient under hypothermic circulatory arrest and selective cerebral perfusion. A single-branched arch graft was used in both patients, and its pre-sewn side branch was used for antegrade perfusion during cardiopulmonary bypass (CPB). During the warming and weaning of each patient from CPB, an 8-mm, ring-attached polytetrafluoroethylene (PTFE) graft was anastomosed to the femoral artery of the ischemic limb. The opposite end of the graft was guided from the groin to the anterior chest through the ventral subcutaneous route and was passed into the pericardial cavity through the anterior intercostal space. After CPB was terminated and before protamine was given, the proximal end of the PTFE graft was anastomosed to the pre-sewn side branch in the pericardial cavity in only a few minutes (Fig. 1). Postoperative computed tomography revealed that the new aortofemoral bypasses were patent, with no limb ischemia (Fig. 2).

Fig. 1 Patient 2. Intraoperative photograph shows the anastomosis of the polytetrafluoroethylene graft to the pre-sewn graft (arrow).

Fig. 2 Patient 2. Postoperative computed tomogram shows the new aortofemoral bypass (arrow).

Discussion

This novel procedure has 2 advantages. First, it is less invasive than other procedures, because it requires less operative time for the aortic replacement. The distal anastomosis can be completed while the patient is warmed and weaned from CPB, and the proximal anastomosis takes only a few minutes.

Second, our procedure has a good prognosis for patency. Baird and colleagues² reported a 5-year patency of 70% for aortofemoral bypass when the inflow source was supplied from the ascending aorta, as with the present technique. This is better than the patency of other extra-anatomic reconstructions, such as femorofemoral bypass (52%–80%) and axillofemoral bypass (20%–62%).³

Furthermore, in our patients, the inflow source from the pre-sewn side branch was made of a graft–graft anastomosis and was not affected by the arteriosclerosis of the native artery that would cause deterioration of the anastomosis. Therefore, the outcome should be better than that reported by Baird and colleagues.² Postoperatively, our patients' grafts showed no occlusion or stenosis as of 25 and 52 months' follow-up.

Mediastinitis after this procedure is a potential concern, because the groin is exposed while the chest is open, and the mediastinal space is connected with the groin through the vascular prosthesis that runs subcutaneously. However, Jebara and co-authors⁴ reported 10 cases of ascending aorta–bifemoral bypass surgery combined with coronary revascularization, and they encountered no infectious complications in any of those patients. Neither superficial nor deep infections occurred in our patients during the follow-up periods.

We chose the subcutaneous route from the groin to the chest, because passing the graft into the pericardial cavity through the anterior intercostal space is easy. Although graft compression is of potential concern when this route is used, we believe that it can be prevented by attaching the graft with a ring. Baird and colleagues² described another path that passed behind the rectus muscle and subxiphoid. They claimed that their route was less visible, less palpable, and less compressible than the subcutaneous route. However, the optimal pathway remains controversial.

In conclusion, our novel technique of using a pre-sewn ascending aortic branch as an inflow source for aortofemoral bypass is a good option as a concomitant procedure during thoracic aortic replacement, because less operative time is required and favorable patency can be expected. We believe that ours is the first report of this technique.