Among patients unsuitable for urgent surgical repair of ascending aortic dissection, endovascular treatment with stent grafting appears to yield acceptable outcomes, according to recent findings.
In the study, researchers evaluated 15 patients with type A aortic dissection (mean age, 65 years; range, 45-78 years) who were admitted to Changhai Hospital, Second Military Medical University, China, from May 2009 to January 2011, and were unfit for open surgery.
Eligible participants included those considered poor candidates for endovascular surgical repair based on the following criteria: advanced age (older than 70 years), American Society of Anesthesiologists classification of IV or higher, NYHA functional class III or worse, prior sternotomy or dysfunction of other essential organ systems.
Patients underwent endovascular repair with stent grafting (aortic dissections consisted of one acute dissection, seven subacute dissections and seven chronic dissections) and were monitored closely for a median of 72 months (range, 61-81 months).
The mean period between onset of aortic dissection and treatment was 25.5 months (range, 61 to 81 months). Follow-up included physical examination, echocardiography, CTA scans and morbidity/mortality documentation at 6 months after the procedure and yearly thereafter.
The researchers found that the procedure had a 100% technical success rate and yielded no perioperative major morbidity or deaths. During follow-up, there were no deaths, eight morbidities and four reinterventions. One new dissection in the aortic arch occurred and was treated with a branched endograft. One patient experienced a retrograde aortic dissection and a left ventricular pseudoaneurysm, and this was successfully treated with open surgery, the researchers wrote. Stenting was used to treat one CV ischemia during follow-up, and radiofrequency ablation was used to treat one supraventricular tachycardia. The following additional morbidities were seen: perigraft endoleak, a bird-beak sign at the distal landing site, a temporary pericardial effusion and a left kidney atrophy.
At 12 months, there were significant enlargements of true lumens and shrinkage of false lumens and overall thoracic aorta. After this time point, no significant changes were observed. The researchers documented only a minor influence on aortic valve function over time.
The preoperative LV end-diastolic diameter was 38.9 mm ± 10.6; it was 42.1 mm ± 5.4 (P = .324) at the end of follow-up. LV ejection fraction was 53.6% ± 2.5 before the procedure and 52.5% ± 2.1 (P = .219) after follow-up.
Ready for next phase
In an accompanying editorial, Michael D. Dake, MD, of the Falk Cardiovascular Research Center and the department of cardiothoracic surgery, Stanford University School of Medicine, wrote these findings are encouraging for endovascular repair, but larger studies will be needed to provide conclusive evidence.
Michael D. Dake
“As the first report to provide details of long-term outcomes following [thoracic endovascular aortic repair] of patients with type A dissection, [the researchers] have succeeded in moving beyond the novelty level of ‘look, it can be done’ to the next developmental stage, poised on the threshold of a prospective clinical trial,” Dake wrote. “This is a valuable contribution. I wonder, however, if the current [thoracic endovascular aortic repair] technology is ready to withstand the rigors it will face when we enter the next phase.” – by Jennifer Byrne
Disclosure: The researchers and Dake report no relevant disclosures.