Key Factor to Prevent Aortic Root and Descending Thoracic Aorta Enlargement after Aortic Valve and Ascending Aorta Combined Surgery

Objective: aortic root enlargement (ARE) and descending thoracic aorta dilatation (DTAD) in combined aortic valve and ascending aorta replacement surgery (AV+AAR) are postoperative concerning issues. This retrospective observational analysis studies surgical factors which could determine those complications. Methods: 236 patients underwent AV+AAR. Mean-time follow-up by trans-thoracic echocardiography (TTE) and computer tomography (CT) was 44.7 ± 21.2 and 38.2 ± 18.4 months respectively. In long-term follow-up, outcome variables are: ARE equal/more than 10% of the preoperative TTE data and DTAD equal more than 5% of preoperative CT measurement at the same thoracic vertebrae axial slice. Results: ARE and DTAD appear strictly related to the discrepancy between prosthetic valve and straight vascular prosthesis diameters (p = 0.024), while there is not significant difference (log-rank = 0.917) related to aortic valve surgery type (replacement or repair). Considering diameter difference (DD) between vascular and aortic valve prosthesis, patients were subsequently grouped into two sections: L5 group, in which DD was less/equal than 5 mm, and M5, in which DD was more/equal than 5 mm. ARE was found in 30.8 % of L5 patients and only in 14.7 % among M5 patients (log-rank = 0.026). We have also observed descending thoracic aorta dilatation in 34.2 % of L5 and in 12.1 % of M5 (log-rank = 0.023). Conclusions: According with our data, difference between vascular prosthesis and aortic valve prosthesis equal/more than 5 mm is a protective factor against ARE and DATD.