Frozen elephant trunk: a narrative review of global and temporal trends

The frozen elephant trunk (FET) repair has transitioned from a niche procedure to a widely adopted strategy across Asia, Europe, and North America. Multicenter registries demonstrate improving early outcomes over time, consistent with learning curve effects. Regional differences persist in case mix, device availability, and utilization. No study has systematically measured these regional differences. We aim to describe the history, evolution, and current landscape of FET worldwide.

A narrative review of English-language adult studies from PubMed, Google Scholar and International Clinical Guidelines (January 2010-September 2025) was performed using procedural and device terminology. Multicenter registries and large single-center series reporting case volumes and outcomes (mortality, stroke, spinal cord ischemia) were included. Data on indication, regional techniques, device use, and clinical outcomes were extracted to identify global and temporal trends.

FET utilization demonstrates wide regional variability, further obscured by heterogeneity in published studies reporting either acute type A aortic dissection (ATAAD) specific or mixed pathology cohorts. China exhibits the highest utilization (48-78% of ATAAD patients). Japan has shown substantial growth over the past decade, with contemporary data indicating FET use in 20% of thoracic aortic cases. In contrast, United States utilization remains low (<5% in mixed cohorts) and European adoption is similarly modest (<10% across arch series). Evidence suggests a procedural learning curve, with higher institutional volume and contemporary practice associated with improved outcomes. Global FET series report operative mortality of 4-12% for ATAAD and 2.5-13% across mixed pathologies, stroke rates of 3-9%, and paraplegia rates of 2-6%. Recent systematic reviews demonstrate 5-year survival of 78-82% and freedom from reintervention of 87%. These gains appear linked to convergence toward moderate hypothermia with selective antegrade cerebral perfusion, proximalization of the distal anastomosis to zone 2, and shorter stents to reduce spinal cord injury.

Global FET volume has risen markedly over two decades, driven by standardization of neuroprotective techniques and advanced hybrid prostheses. A core set of principles has emerged establishing FET as a safe and versatile option for complex aortic disease worldwide. However, differences in devices, patient populations, and procedural indications remain.