A study that compared the durability of thoracic endovascular aortic repair (TEVAR) in two similar clinical trials, one that used early-generation and another that used later-generation stent grafts, found a significantly lower freedom from reintervention rate for patients who received the newer stent grafts.
The study, published in the Journal of Vascular and Interventional Radiology in February, by Alan Matsumoto, Department of Radiology and Medical Imaging, University of Virginia Health System, Charlottesville, USA, and colleagues, compared the durability of TEVAR after the VALOR and VALOR II trials.
The researchers concluded that the finding from the study suggested “significant benefit from advances in some combination of operator experience imaging systems, treatment planning and device design.”
Matsumoto and colleagues analysed the secondary procedures from the prospective, non-randomised, multicentre, clinical trial databases of the test arms of the VALOR and VALOR II trials at three years. They used descriptive and statistical analyses to compare the rate of and potential predictors for secondary procedures.
VALOR evaluated the Talent Thoracic Stent Graft System (Medtronic) for the treatment of thoracic aortic aneurysms and enrolled 195 patients with thoracic aortic aneurysms who were considered candidates for open surgical repair. VALOR II evaluated the clinical performance of the Valiant Thoracic Stent Graft System (Medtronic) in the treatment of descending thoracic aneurysms of degenerative aetiology in patients who were candidates for endovascular repair.
The investigators had data from 127 patients for a minimum of three years of follow-up from the test arm of the VALOR trial. Similarly, there were data from 96 patients with three-year follow-up information available to the researchers from the test arm of VALOR II. The researchers found that by the first year after the index procedure, VALOR II patients were significantly less likely to have undergone a secondary procedure vs. patients in the test arm of VALOR (odds ratio, 0.08; 95% confidence interval, 0.01–0.63; p=0.02), with most reinterventions being performed to treat type I endoleak. Multivariate predictors at three years for the need for a secondary procedure in the VALOR test arm were maximum aneurysm diameter (p=0.002) and aneurysm length (p=0.01), both of which remained significant at the end of the study period.
The estimated freedoms from secondary procedures in the VALOR test arm and VALOR II at three years were 85.1% and 94.9%, respectively (p<0.001). The investigators found that the rate of secondary procedures after TEVAR differed between the two cohorts, being substantially lower in the VALOR II trial at one year of follow-up.