1. Conventional and frozen elephant trunk surgery for extensive aneurysmal disease of the thoracic aorta: a retrospective comparative study Marco Di Eusanio 1, Michael A. Borger 2, Francesco D. Petridis 1, Sergei Leontyev 2, Antonio Pantaleo 1, Monica Moz 2, Friedrich W. Mohr 2 and Roberto Di Bartolomeo 1 1 Departments of Cardiac Surgery, S. Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy 2 Department of Cardiac Surgery, Heart Center, University of Leipzig, Leipzig, Germany

2. Different surgical and hybrid procedures are available to treat patients with extensive disease of the thoracic aorta. No comparative studies exist comparing short- and mid- term outcomes after extensive aneurysm repair using the Conventional Elephant Trunk (ET) and the Frozen Elephant Trunk (FET) procedures. Here we report our experience BACKGROUND

3. Extensive aneurysms of thoracic aorta n=57 FET n=21 ET n=36 Exclusion criteria: aortic dissection descending thoracic aorta < 40 mm thoraco-abdominal aneurysm method of brain protection other then antegrade selective brain perfusion STUDY POPULATION

4. Patients’ characteristics. ET (n=36)FET (n=21) n(%) p Age64.36±10.8165.64±7.370.144 Gender (female)17(47.2%)3(14.3%)0.011 COPD4(11.1%)5(23.8%)0.185 Renal Failure3(8.3%)-0.244 Cad6(37.5%)-0.009 Diabetes3(8.3%)3(14.3%)0.387 Smoking6(40%) 0.645 Hypertension12(75%)13(76.5%)0.619 Cerebral Vasculopaty3(8.3%)3(14.3%)0.387 Redo4(11.1%)6(28.6%)0.096

5. Surgical techniques ET (n=36)FET (n=21) n(%) p Arterial cannulation 0.024 Femoral10(27.8%)1(4.8%) Axillary20(55.6%)10(47.6%) Ascending Ao2(5.6%)4(19.0%) Femoral/Axillary4(11.1%)2(9.5%) Brachiocefalic Trunk-3(14.3%) Others-1(4.8%) Arch vessel reimplantation 0.154 Island23(63.9%)11(52.4%) Separated graft13(36.1%)8(38.1%) none-2(9.5%)

6. Surgical techniques (continued) ET (n=36)FET (n=21) n(%) p Associated procedures20(55.6%)5(23.8%)0.019 MV repair2(5.6%)- AV repair5(13.9%)- AV replacement6(16.7%)4(19.0%) CABG8(22.2%)1(4.8%) Bentall3(8.3%)- Aortic valve reimplantation5(13.9%)- CPB time (min)202.03±69.58204.43±61.770.583 Aortic X-clamp time (min)118.31±51.95107.05±48.130.997 ASCP time (min)45.28±37.9667.33±26.900.363 Visceral ischemia time (min)62.40±18.3161.24±19.230.272

7. Hospital outcomes ET (n=36)FET (n=21) n(%) p Hospital death5/36(13.9%)1/21(4.8%)0.272 Stroke-coma2/35(5.7%)2/21(9.5%)0.483 Paraplegia1/35(2.9%)1/21(4.8%)0.614 Ventilatory support>3 days 7/36(19.4%)4/21(19%)0.628 Dialysis2/36(5.6%)2/21(9.5%)0.471 Bleeding5/36(13.9%)1/21(4.8%)0.272

8. 1y2yy3yy4yy ET survival (%)80.1 75.8 pts at risk (n)21201713 FET survival (%)79.472.8 pts at risk (n)12533 Log Rank= 0.816

9. CONCLUSION In patients with extensive aneurysms of the thoracic aorta ET and FET procedures were associated with similar satisfactory short- and mid- term outcomes. Longer-term follow up are warranted