An Aortic Arch Aneurysm Developing Late after a Non-anatomical Bypass Surgery for an Aortic Coarctation in Adulthood / 日本心臓血管外科学会雑誌

ABSTRACT

A 48-year-old man underwent an non-anatomical bypass surgery for aortic coarctation when he was 38 years old, when a bypass laid between the left subclavian artery and the descending aorta with a prosthesis (10 mm, internal diameter). Four years after the first surgery, aortic aneurysms at the proximal and distal sites of the coarctation were detected. Six years from then, we decided to perform another surgery when the maximum diameters of the proximal and distal sites exceeded 60 and 47 mm, respectively. We performed the aortic replacement from the proximal left subclavian artery to the descending aorta at eighth thoracic vertebra. The approach to the aortic aneurysm was through the extended left thoracotomy with the transection of the sternum. The cardiopulmonary bypass was established with an antegrade aortic perfusion (from the ascending aorta) and drainage from the right atrium. The circulatory arrest was obtained under deep hypothermia at 20°C measured by deep body temperature. After the surgery, the pressure differences between upper and lower extremities decreased to 10 mmHg, which had been 40 mmHg before surgery. Macroscopic observation showed the coarctation site was completely obstructed by an old thrombus. From this observation, we surmise that one of the reasons for the aneurysmal formation at the proximal site of coarctation might be an insufficient depressurization by the non-anatomical bypass grafting from the left subclavian artery to the descending aorta at the first surgery. We consider that a severe coarctation might become thrombotic sooner or later after a non-anatomical bypass surgery due to a change of blood flow, and a radical anatomical surgery would be recommended for adult coarctation cases.