Considering valve competence
Using a supracoronary interposition graft and resuspension of the native aortic valve, has numerous potential advantages over aortic valve replacement. The approach is technically more straightforward than root replacement, the latter requiring more operative steps and technical skill, especially in the emergency setting. Additionally, in young patients who are otherwise likely to receive a mechanical valve replacement, native valve preservation avoids the risks of long term anticoagulation, including delayed false lumen thrombosis and haemorrhagic events. Keeping the native aortic valve also leaves many options open for reintervention decades down the line should the younger patient require it. In older patients, especially when the native leaflets exhibit normal morphology, avoiding bioprosthetic valve replacement may defer complications associated with structural valve degeneration [4].
Studies have supported the choice of supracoronary interposition grafting in ATAAD in patients without a definitive indication for aortic valve replacement. The present study goes further: even with severe AR at the time of emergency surgery, valve resuspension can yield good long-term results and severe AR should not be a considered a contraindication for AAG. Few studies have examined the performance of the native aortic valve following type A aortic dissection and in these there is a lack of consensus regarding the significance of aortic regurgitation at presentation. Molteni et al. and Tang et al. found that aortic regurgitation at presentation was not a predictor of subsequent reintervention of the aortic valve or aortic regurgitation in a retrospective case series [14][15]. In contrast Pesottoet al. did find that moderate or severe aortic regurgitation at presentation was associated with an increased risk of moderate or severe aortic regurgitation during follow-up in patients undergoing aortic valve resuspension [16].
The long-term durability of the native aortic valve and root was found to be good in this case series. In total six patients in this series required reintervention on the native aortic root or valve. A modest deterioration in the function of the native aortic valve was observed with 9 and 3 patients developing moderate and severe aortic regurgitation respectively following discharge.