Joseph Lombardi, Philadelphia, USA, presented two-year results of STABLE (The study of thoracic aortic type b dissection using endoluminal repair) today. STABLE, he said, is a prospective, non-randomised, multicentre clinical study conducted at investigational sites in Europe, Australia, and the United States to demonstrate the safety and effectiveness of the Cook Zenith Dissection Endovascular System in the treatment of patients with type B aortic dissection.

Developed as a less invasive alternative to open surgical repair and specifically for the treatment of type B aortic dissections, this system comprises the Zenith TX2 Thoracic Aortic Aneurysm Endovascular Graft with Pro-Form and the Zenith Dissection Endovascular Stent. “The combined use of proximal stent-graft and distal bare stent components provides a means to seal the primary entry tear and support the necessary length of dissection without risk from coverage of branch vessels,” Lombardi said.

A total of 86 patients (73% male, mean age 59 years) were enrolled in the STABLE study. More than half of the patients (64%) were treated in the acute phase (within 14 days of symptom onset) and a majority (73%) had presenting symptoms of impending aortic rupture and/or branch vessel malperfusion.

Lombardi, global principal investigator of the study, presented study results through 24 months, reflective of data received as of March 2013. The overall 30-day mortality rate was 4.7% (4/86), and Kaplan-Meier estimates of patient survival were 88% at 12 months and 85% at 24 months. During follow-up through two years, five patients experienced aortic rupture and no patient required conversion to open repair. There were seven cases of stroke (six cases within 30 days) and one case of paraplegia (within 30 days). Renal failure occurred in nine patients (none required permanent dialysis) and retrograde dissection occurred in seven patients (two patients died; four underwent re-interventions). Aortic remodeling, indicated by an increase in the true lumen size and a decrease in the false lumen size, was observed in both the descending thoracic aorta and the distal abdominal aorta.

“These results continue to indicate favourable clinical and anatomic outcomes with the use of a composite TEVAR construct. Follow-up through five years is ongoing to assess long-term effectiveness of this treatment strategy,” Lombardi stated.