G. El Khoury

The aortic root: structure, function, and surgical reconstruction

Aortic valve insufficiency may be caused by abnormalities of the leaflets, the root, or a combination of both. In some patients, the primary pathology is confined to the aortic root itself, the leaflets remaining anatomically normal. These patients have progressive dilatation of the aortic sinuses and, on occasion, dilatation and distortion of the annulus which results in valvar incompetence.1 Most cases are “idiopathic” (annuloaortic ectasia) but it may be associated with a wide spectrum of pathological conditions which include the Marfan syndrome,2 aortic dissection and aortitis,3 4 along with rare systemic disorders such as Ehlers-Danlos syndrome.5 Aortic root pathology has now been reported as the most common cause of aortic valve incompetence in the United States, an observation which probably reflects the decline of rheumatic valve disease.1Current conventional treatment for patients with significant aortic incompetence caused by a dilated, aneurysmal aortic root is replacement of the ascending aorta using a synthetic graft, replacement of the aortic valve with a mechanical prosthesis (the graft and prosthesis are usually combined as a “composite graft”), and reimplantation of the coronary arteries. In selected cases where there is no suspicion about the future integrity of the sinuses but there is dilatation of the ascending aorta, the valve and ascending aorta may be replaced separately. Despite the success of these operations, they both involve implantation of a prosthetic valve; complications such as thromboembolism, endocarditis, and problems related to the long term anticoagulation required have provided the impetus for the development of a surgical procedure which will preserve the native aortic valve. In this article we review the structure and function of the aortic root, the pathophysiological changes that may lead to aortic incompetence despite anatomically normal valve leaflets, and the surgical procedure which has been developed as a result …

Free internal mammary artery graft in myocardial revascularization.

Between August 1986 and March 1993, 124 patients (102 men; mean age of 59 years) underwent myocardial revascularization with the use of at least one free internal mammary artery (FIMA). This group represents 4.5% of the 2725 coronary bypasses performed during the same period. Seventy-six patients (61%) had suffered from at least one previous myocardial infarction. Forty-five patients (36%) had unstable angina; three-vessel disease was found in 100 cases (80.5%) and a left ventricular ejection fraction lower than 0.4 in 22 (17.7%). There were 18 (14.5%) redo procedures and 90 (72.5%) bilateral internal mammary artery (IMA) grafts. The reasons for using a FIMA were: too short an internal mammary artery pedicle in 83 patients, IMA injury at harvesting in 30 patients and post-bypass ischaemia in areas grafted with pedicled IMA (PIMA) in 11 patients. Cardiopulmonary bypass, moderate hypothermia (30 degrees C) and crystalloid anterograde and retrograde cardioplegia were used in all cases. Sixty-seven FIMA grafts were anastomosed directly to the ascending aorta; 57 were sutured via a saphenous hood using a running suture of polypropylene 7/0 and three were anastomosed end-to-end to a PIMA graft. FIMA grafts were directed to the left anterior descending (34%), the circumflex (37%) and the right coronary artery (29%). In total, 179 anastomoses were constructed using 127 FIMA, 136 using PIMA and 158 using saphenous veins (3.8 anastomoses per patient). Hospital mortality and postoperative myocardial infarction rates were 5.6% (seven patients) and 3.2% (four patients), respectively. Cardiac-related mortality was 3.2% (four patients); three of these four patients had been operated on for evolving infarction and one underwent a redo procedure. Four of the 117 survivors died later on; in two, it was cardiac-related and a result of global heart failure at 9 and 12 months. Of the 113 remaining patients, 106 are symptom free after a mean follow-up of 28.2 (range 3-84) months. Fifty-nine patients (50.4%) were restudied by angiography at a mean interval of 15 months. Patency rates of FIMA anastomosed either directly to the aorta or via a saphenous hood were 82.8 or 89.7%, respectively. Patency rates of FIMA directed to the left anterior descending, the circumflex and the right coronary artery were 85.7, 88 and 83.3%, respectively. Global FIMA patency was 86.4%, while global PIMA patency was 100%. The FIMA mid-term patency rates compare unfavourably with those of PIMA: FIMA should therefore be restricted to the cases where PIMA or other pedicled arterial grafts are unavailable.

Endovascular treatment of acute aortic isthmic rupture: concerning midterm results.

BACKGROUND We evaluated midterm results of endovascular management of traumatic aortic isthmic ruptures. METHODS Between 2001 and 2008, 10 patients (seven males, mean age 38 years) underwent endovascular treatment of an acute aortic rupture. Eight procedures were emergent, with four cases of hemodynamic instability with Glasgow scores of 3, 5, and 7. Associated traumas were severe brain, liver, and pelvic bone injuries. All procedures were performed with transoesophageal echocardiography monitoring. We used two AneuRx and nine Medtronic Talent or Valiant stent grafts. RESULTS All patients survived their traumatic isthmic rupture. In nine patients, stent-graft deployment was successful. One patient experienced a distal migration needing a laparotomy and deployment of an additional new thoracic stent graft. The mean intensive care unit stay was 48 hr (range 24-168). The mean hospital stay was 11 days (range 8-43). All patients were controlled clinically and by contrast computed tomography (CT) according to the EUROSTAR protocol. There were no endoleaks, stent graft-related complications, or late deaths during a mean follow-up of 49 months. The control CT showed a lack of apposition of the proximal part of the stent graft at the inner curve of the aortic arch in three patients. CONCLUSION The midterm results of endovascular treatment of acute traumatic aortic isthmic rupture are encouraging and compare favorably to the surgical approach. Late follow-up is required to exclude possible stent-graft complications, especially in young patients with angulated aortic arches.