Single-center midterm results with the low-profile Zenith Alpha thoracic endovascular stent graft

The analysis of endovascular treatment of thoracic aortic diseases using new low-profile stent grafts in large series is crucial to understanding the durability of these devices. The present study reports the midterm outcomes of a single-center experience using the Zenith Alpha thoracic endovascular stent graft.

The outcomes of 270 procedures performed on 262 patients (197 men; mean age, 70.5 ± 9.5 years) using the Zenith Alpha thoracic endovascular stent graft from November 2013 to December 2019 for different thoracic aortic diseases were analyzed. The primary endpoints were 30-day clinical success and midterm (5-year) clinical success. The secondary endpoints were the adverse event rate at 30 days and midterm and access- and device-related complications. The follow-up of surviving patients was performed using computed tomography angiography and office visits at 1, 6, and 12 months and annually thereafter. Kaplan-Meier analysis was performed for overall survival, and freedom from thoracic aortic endovascular repair-related mortality and related reinterventions.

The overall 30-day mortality was 5.2% (2.5% for elective and 30.8% for nonelective cases). Type I endoleaks were identified in six patients. The 30-day primary technical and clinical success rates were 97.8% and 92.6%, respectively. Femoral cutdown was used in 41.1% of cases and percutaneous access in 58.5%. The rate of femoral artery complications after the percutaneous approach was 5.1%, with the need for surgical conversion in 1.9%. The stroke rate was 4.1% (major stroke, 2.2%), and the spinal cord ischemia rate was 3.7% (permanent paraplegia, 0.7%). Of the 248 survivors, 239 complied with the follow-up protocol with adequate computed tomography angiograms available images. Overall follow-up survival was 94.0% at 1 year, 91.6% at 2 years, 88.9% at 3 years, and 88.5% at 5 years. The unplanned secondary endovascular procedure rate was 5.3%. No stent fractures or new-onset type I endoleaks due to stent graft migration were observed in the study cohort.

The midterm outcomes of this new generation of low-profile devices were satisfactory. The reported low incidence of secondary procedures and the absence of migrations are promising for the long-term durability of these devices.