A direct approach to repair thoracic coarctation may entail difficulties in the adult population.
Concurrent aortic and cardiac pathology represents a rare entity. This report describes a technique of addressing a complex pathology: a patient with an aortic coarctation, an ascending aortic aneurysm and end stage ischaemic cardiomyopathy.
A 58 years old male presented with tachycardia and biventricular failure. Investigations revealed a 9 cm ascending aortic aneurysm containing a dissection flap above a regurgitant bicuspid aortic valve. Despite anti-failure treatment the ejection fraction remained in the range of 15-20%. A CT scan and an MRI (Figure 1) further delineated the ascending aortic aneurysm and revealed an unsuspected but very tight coarctation with good collaterals. A subsequent attempt at coronary angiography failed because of inability to engage the grossly displaced coronary ostia. Very extensive coronary calcification, reaching out to the terminal branches of the major epicardial vessels was however revealed. The conventional procedure would have entailed aortic valve and ascending aortic replacement together with blind CABG and repair of the coarctation. Further episodes of heart failure persuaded us that transplantation was a more acceptable argument. The potential difficulties of grafting only small distal vessels in a patient who already had severe left ventricular dysfunction was a major factor in this decision. The patient was accepted on to the transplant waiting list.
Because of his ambulatory nature he remained on the waiting list whilst gradually deteriorating. He was admitted as an emergency with gross congestive heart failure some 11 months after listing. At that time repeat right heart catheter revealed a mean pulmonary artery pressure of 42 with a pulmonary artery papillary wedge of 36 and a cardiac index of less than 2. His creatinine had risen to 137 mm/l. He was admitted to hospital and treated with Dobutamine and Frusemide infusion and listed for urgent transplantation.
After a further 10 days a donor heart of a 17 year old male of acceptable weight and height became available to us. The most striking finding at the operation of the recipient was the huge ascending aortic aneurysm which contained a dissection flap. There were very poor left ventricular function and grossly elevated filling pressures. Bypass was established via bicaval venous cannulation and the underside of the aortic arch. The aorta was cross clamped just proximal to the innominate artery, distal to the dissection flap and at a point where the aorta measured approximately 4 cm in diameter. Straightforward removal of the recipient's heart was performed whilst he was cooled to 18 C. In the meanwhile the left lung could be reflected into the now empty pericardial cavity and the area of the coarctation exposed. A good view was obtained although it was not feasible to place a clamp proximally as the arch of the aorta disappeared out of the field of vision.
Once the patient was stable at 18 C circulatory arrest was instituted. The coarctation was incised vertically. It had been planned to place an on laid patch but this was clearly not going to be possible so the coarctation area was excised. A short length of 24 mm Vascutek graft was then sutured in an end to end fashion between the two cut ends of the aorta. Total circulatory arrest time for this rather awkward anastomosis was 36 minutes. After initial deairing the circulation was restored and the patient rewarmed. A relatively straightforward orthotopic cardiac transplant was performed with bicaval cannulation. The aortic anastomosis was on to the donor aorta, obliquely divided at the level of the innominate artery. Donor heart ischaemic time was 78 minutes. Post-operatively he had periods of profound vasodilatation and subsequent confusion. He was ventilated for 8 days and underwent a tracheostomy on day five. He eventually made a full recovery with no residual neurological deficit and was discharged home at 28 days. There was no measurable difference, by non invasive techniques, between upper and lower limb blood pressure at that time.