Body Height and Stentgraft Diameter Drive Thrombus Formation After Frozen Elephant Trunk Repair: A Risk-Focused Analysis

All articles of this category (opens in new window) Background: Intraluminal thrombus formation is an increasingly recognized and clinically significant complication after frozen elephant trunk repair, potentially associated with substantial morbidity and risk of embolic events This study aims to identify key patient and device factors driving thrombus risk to optimize prevention and management strategies. Methods: Retrospective analysis of 458 patients undergoing FET repair was performed, evaluating clinical, procedural, and device-related parameters for their association with postoperative thrombus formation using Fine-Gray subdistribution hazard models. Both univariable and multivariable regressions were employed for both the risk of thrombus formation and the hazard of death during follow-up. Risk was visualized using a stentgraft size-to-height-adjusted heatmap, and the prognostic impact of thrombus size was modeled with restricted cubic splines. Results: Multivariable analysis identified the standardized stentgraft size-to-patient height ratio as an independent risk factor for thrombus development after FET implantation (HR: 1.528 [1.132–2.062]; p = 0.006). The risk map indicates that patients with large stentgraft diameters in relation to shorter stature are at the highest risk (Table 1). While new FET thrombus alone did not reach significance in predicting mortality (HR: 1.178 [0.604–2.297]; p = 0.631), the maximum diameter of FET thrombus was a significant predictor of death during follow-up (HR: 1.13 [1.041–1.227]; p = 0.004), with a nonlinear increase in hazard ratio with increasing size. These findings enable stratification of risk based on actionable, patient-specific, and surgical factors. Conclusion: Post-FET thrombus risk is highest in patients with a disproportionately large stentgraft relative to their height, rather than BMI, weight, or BSA. Device selection should prioritize an optimal balance between down and upsizing relative to patient height, and perioperative management must include intensified surveillance for patients where increased upsizing was necessary. Any postoperative thrombus exceeding 30 mm in diameter requires prompt radiological assessment and consideration of escalation in clinical monitoring, as it may be associated with poorer long-term mortality. Publication History Article published online: 17 February 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany