Acute type A aortic dissection (ATAAD) surgery is different from elective surgeries of aortic root and ascending aorta due to higher fragility of tissues, increased operative mortality and mortality, and longterm increased rates of reintervention. In particular, proximal repair (aortic root management) and distal repair strategies are the most important factors affecting the long-term patient outcomes.

In their retrospective study regarding aortic root management, Kose et al.[1] studied 68 patients with a mean age of 54.2±10.1 years for an average of 4.9±3.1 years following a root protective surgery (supracoronary graft interposition without commissural resuspension). Of 64 patients, 32 (47.06%) had sinus of Valsalva (SOV) dilatation (SOV diameter: 5.23±0.61 cm), while 36 (52.94%) had normal SOV (SOV diameter: 3.74±0.43 cm). The authors concluded that preoperative SOV diameter was a risk factor for aneurysmatic dilatation. A diameter of 4.05 cm and above was calculated as a cutoff value for developing dilatation requiring reoperation.

In ATAAD surgery, it is important to consider patient's clinical status before surgery, severity and mechanism of aortic regurgitation (AR) and presence of coronary malperfusion. Aortic regurgitation is often caused by a dissection flap extending below the sinotubular junction, causing detachment and prolapse of one or more of the aortic valve commissures. Therefore, determining the aortic root diameter preoperatively via computed tomography scan or echocardiogram may not be sufficient alone in deciding on a surgical strategy. Rather, an intraoperative decision-making process after the restoration of the aortic root and resuspension of the commissures should be used in determining the next steps.

According to the current guidelines, in patients with a partially dissected aortic root but no significant leaflet pathology, aortic valve resuspension is recommended over valve replacement (Class I). In patients with extensive destruction of the aortic root, a root aneurysm, or a known genetic aortic disorder, aortic root replacement is recommended with a mechanical or biological valved conduit (Class I). In selected patients who are stable, valve-sparing root repair may be reasonable, when performed by experienced surgeons (Class IIa).[2] If the tear is in the noncoronary sinus, replacement of a single sinus might be considered (partial remodeling).[3] In bicuspid aortic valve, some retrospective series have shown that patients with ATAAD present at a younger age and undergo root replacement more often than those with tricuspid valves.[4,5]

Several retrospective studies have compared the early and late outcomes after root replacement versus root repair. In these studies, the diameter of the aortic root above ≥4.5 cm was one of the indications of the root replacement.[6] The reason that Kose et al.'s[1] study found a preoperative SOV diameter of ≥4.05 cm as a reoperation risk factor could be not resuspending the commissures and having a younger patient population in the study. In my professional opinion, further studies are necessary to correlate the preoperative SOV diameter and reoperation risk.

In conclusion, we should make the final decision of aortic root preservation or replacement based on our surgical experience and judgement. We need to maximize long-term benefit, but also consider limiting the early operative risk.

References

1) Köse Y, Özyurt Köse S, Koçoğulları CU. Dilated sinuses of Valsalva subsequent to type A dissection surgery: Is reoperation inevitable?. Turk Gogus Kalp Dama 2023;31:171-75. doi: 10.5606/tgkdc.dergisi.2023.24330.

2) Isselbacher EM, Preventza O, Hamilton Black J 3rd, Augoustides JG, Beck AW, Bolen MA, et al. 2022 ACC/ AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/ American College of Cardiology Joint Committee on Clinical Practice Guidelines. Circulation 2022;146:e334-e482. doi:10.1161/CIR.0000000000001106.

3) Svensson LG. Limited Intimal Aorta Tears: Royalty Torn Asunder, and a Nation Was Created. J Am Coll Cardiol 2018;71:2786-2789. doi: 10.1016/j.jacc.2018.03.530.

4) Kreibich M, Rylski B, Czerny M, Pingpoh C, Siepe M, Beyersdorf F, et al. Type A Aortic Dissection in Patients With Bicuspid Aortic Valve Aortopathy. Ann Thorac Surg 2020;109:94-100. doi: 10.1016/j.athoracsur.2019.05.022.

5) Mennander A, Olsson C, Jeppsson A, Geirsson A, Hjortdal V, Hansson EC, et al. The significance of bicuspid aortic valve after surgery for acute type A aortic dissection. J Thorac Cardiovasc Surg 2020;159:760-767.e3. doi: 10.1016/j. jtcvs.2019.03.012.

6) Malaisrie SC, Szeto WY, Halas M, Girardi LN, Coselli JS, Sundt TM 3rd, et al. AATS Clinical Practice Standards Committee: Adult Cardiac Surgery. 2021 The American Association for Thoracic Surgery expert consensus document: Surgical treatment of acute type A aortic dissection. J Thorac Cardiovasc Surg 2021;162:735-758.e2. doi: 10.1016/j. jtcvs.2021.04.053.