Frozen elephant trunk in normothermia without circulatory arrest: initial experience.

Background: Aortic arch surgery has evolved significantly with novel techniques aimed at reducing morbidity and mortality. Traditional approaches rely on hypothermic circulatory arrest (HCA), which remains associated with neurological and systemic complications. This study presents our initial experience with a normothermic frozen elephant trunk (FET) technique that eliminates circulatory arrest while maintaining continuous cerebral and systemic perfusion. Methods: A retrospective analysis was conducted on consecutive patients who underwent FET without HCA at Polytechnic University of Marche from September 2019 to January 2025. The surgical strategy included femoral and innominate artery cannulation for extracorporeal circulation, antegrade selective cerebral perfusion (ASCP), and retrograde stent graft deployment with balloon occlusion. Perioperative outcomes, complications, and mid-term follow-up data were evaluated. Results: Twenty-three patients (median age, 73 years) underwent FET without HCA. Indications included degenerative aneurysm (n=14), type I endoleak (n=4), acute aortic dissection (n=2), chronic penetrating ulcer (n=2), and Kommerell's diverticulum (n=1). Technical success was 100%. Two in-hospital deaths occurred due to septic shock and stroke. No cases of permanent spinal cord injury were reported. The median intensive care unit and hospital stays were 4 and 10 days, respectively. The median peak intraoperative lactate level was 1.8 mmol/L (range, 1-4.8 mmol/L). At a median follow-up of 27 months, three patients required distal aortic reintervention due to type Ib (n=2) and type II (n=1) endoleaks. Conclusions: Normothermic FET without circulatory arrest is a feasible and potentially advantageous alternative to traditional techniques, reducing ischemia-reperfusion injury while maintaining cerebral and systemic perfusion. Early outcomes suggest promising results in selected patients, though further studies with larger cohorts are necessary to validate long-term safety and efficacy. Keywords: Frozen elephant trunk (FET); normothermic frozen elephant trunk (normothermic FET); cardiac arrest; FET without circulatory arrest; aortic arch surgery.