ALI Risk High After Stent Graft Thrombosis Even With Low Amputation Risk

The risk for acute limb ischemia (ALI) is considerable after stent graft thrombosis, even if the risk for amputation is low, according to a study recently published in JACC: Cardiovascular Interventions.

This retrospective multicenter study included 1215 individuals (mean age, 73±8 years) with long peripheral artery occlusive disease lesions in the femoropopliteal artery, all of whom were treated with VIABAHN® stent graft. Comorbidities included diabetes (57%) and dependence on dialysis (18%). The incidence of stent graft thrombosis was examined, as were the associated symptoms, patency following reintervention, and any factors that predicted post-reintervention loss of patency.

ALI was diagnosed according to international guidelines. Welch’s t-test was used to test intergroup differences with continuous variables and the Mann-Whitney U test to examine the time between implantation and thrombosis. Dichotomous variables were assessed using the chi-square test.

Among the study population, 13% (n=159) developed stent graft thrombosis (median time to thrombosis, 6.4 [interquartile range, 2.8-13.5] months). Of these, 13% (n=21) experienced ALI, 82% (n=131) were treated with reintervention for stent graft thrombosis, 1% (n=2) underwent amputation of the affected limb, and 16% (n=26) received conservative treatment.

At 1 year postintervention, the patency rate was 54.9% (95% CI, 46.3-65.0), the freedom from major adverse limb events was 73.6% (95% CI, 65.6-82.5), and the post-reintervention limb salvage rate was 92.5% (95% CI, 87.5-97.8).

Critical limb-threatening ischemia at the time of stent graft implantation and ALI presentation at stent graft thrombosis showed a positive association with increased re-thrombosis risk. The diameter of the distal stent was negatively correlated with re-thrombosis risk.

Limitations to these findings include a small number of participants, a short follow-up period, an inability to directly compare those who developed thrombosis with those who did not, an inability to investigate ALI risk factors using multivariate analysis, and an inability to investigate the efficacy of each stent graft thrombosis method.

The study researchers concluded that there “was considerable risk of ALI when thrombosis of [stent graft] occurred, even though the risk [for] primary major amputation was not high.” Further, “clinical outcomes after both surgical and endovascular reinterventions for thrombosed [stent grafts] were suboptimal, including low patency and deteriorated ambulatory status.”

The study researchers recommended carefully selecting individuals before stent graft implantation.

Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Ichihashi S, Takahara M, Iida O, et al. Clinical impact of stent graft thrombosis in femoropopliteal arterial lesions. JACC Cardiovasc Interv. 2021;14(10):1137-1147. doi:10.1016/j.jcin.2021.03.030