Acute type A aortic coarctation is a very aggressive surgical emergency, with approximately 50% of patients dying within 48 hours of onset (mortality increases at a rate of 1% per hour during the first 48 hours.) In 2000, Hagan (Hagan) et al. reported that approximately 58% of patients with acute type A aortic coarctation die from a variety of causes, even after hospitalization.
In our country, the incidence of aortic coarctation has its own characteristics.
① The incidence of hypertensive disease in China is high, but the awareness and control rates are low, and thus the age of onset of aortic coarctation is significantly lower than that of foreign patients;
(2) China has a large population base, a large number of patients with equine Fang syndrome, and a younger age of onset. Based on this, it is essential to raise awareness of aortic coarctation and improve its treatment outcome.
The two internationally accepted staging methods for aortic coarctation are the DeBakey staging and the Stanford staging. These two staging methods are simple and easy to grasp, but they also have shortcomings. Firstly, the typing is relatively rough and only simply describes the location of the rupture and the extent of the entrapment, which cannot accurately reflect the specific lesion; secondly, with the progress of science and technology, more and more therapeutic tools are applied to the treatment of aortic entrapment, and these two typing methods cannot accurately guide the selection of the treatment plan and precisely determine the treatment effect of aortic entrapment.
Therefore, the author summarizes many years of experience in the diagnosis and treatment of aortic coarctation and proposes a systematic and quantitative aortic refinement staging method for your reference.
Modified StanfordA type A1, A2, A3 of aortic coarctation staging
Based on the aortic root lesion, StanfordA type aortic coarctation can be classified into A1, A2 and A3 types, and the distal extent of coarctation stripping does not affect this typing. Accordingly, the management of the proximal aorta can be standardized.
Type A1 aortic coarctation
In principle, Stanford type A entrapment should be operated in an emergency after diagnosis. However, due to the uneven distribution of medical resources in China, many patients cannot receive timely and effective treatment. Therefore, it is important to make full use of available resources to buy more time for patients with aortic coarctation and reduce mortality. patients with A1 coarctation have relatively mild disease and rarely have aortic valve insufficiency and myocardial blood supply disorders, so they can be treated surgically in hospitals with adequate preparation.
The surgical approach to the proximal ascending aorta in patients with type A1 coarctation is relatively simple and requires only ascending aortic replacement.
The initial prognosis for type A1 coarctation is relatively simple, with a low rate of near-term mortality and complications, a good long-term prognosis, and no need for postoperative anticoagulation.
Type A2 aortic coarctation
Patients with type A2 coarctation have mild involvement of the aortic sinus, mostly combined with mild to moderate aortic valve insufficiency, and may have coronary artery involvement. In general, this type of patient should be operated on by a deadline after the best possible preparation. However, emergency surgery should be performed when patients present with complications such as unrelieved pain, acute left heart insufficiency, and acute myocardial blood supply disorders.
Surgical approach The choice of the proximal surgical approach for entrapment in patients with A2 type of entrapment is complex and should be based on the degree of involvement of their aortic sinus and aortic valve regurgitation. If the sinus lesion is mild and the aortic regurgitation is low, sinoplasty + aortic valve junction suspension can be performed.
If the sinus lesion is severe and the aortic regurgitation is low to moderate, then aortic sinus replacement + aortic valvuloplasty or David (David) surgery may be considered. In the author’s experience, the David procedure, which preserves the aortic valve, is an option when adequate preparation has been completed in patients with type 2 coarctation (especially in younger patients) and the operator is very experienced. However, if the operator’s experience is limited and the patient has a large aortic regurgitation, the Bentall procedure should be chosen.
The initial prognosis for A2 type of coarctation is more complex and the surgical operation is more difficult, requiring a high level of skill on the part of the surgeon. However, if performed properly, most patients can retain their aortic valve and can avoid anticoagulant medications, thus improving their quality of life. It must be noted, however, that performing David’s surgery in patients with Marfon syndrome is controversial, and if the surgeon is not experienced in treatment, aortic root replacement can be used to avoid reoperation on the patient.
Type A3 aortic coarctation
The timing of surgery for type A3 coarctation is obvious in aortic sinus lesions, and most patients have severe aortic valve insufficiency and some have myocardial ischemia, so most patients should be treated with emergency surgery.
If the coronary opening is not significantly displaced, the Cabrol procedure can be considered.
The initial prognosis of Bentall surgery (or Cabrol surgery) is not technically difficult, the patient is not at high intraoperative risk, and the rate of secondary surgery is low. However, patients require long-term anticoagulation therapy and have a poor quality of life.
Table StanfordA Refinement of aortic coarctation staging
Based on the lesion in the aortic arch, StanfordA type aortic coarctation can be classified into C and S types.
The distal surgical approach to acute Stanford type A coarctation greatly influences the outcome. For example, proximal ascending aortic replacement and partial arch replacement are relatively simple surgical operations with low postoperative patient mortality and complication rates. However, patients (especially those with Marfon syndrome) are more likely to undergo reoperation. In contrast, total aortic arch surgery is a complex operation with a higher rate of patient mortality and complications, but the treatment is more complete. Therefore, the C-type and S-type classification helps the operator to accurately select the appropriate procedure to achieve the best surgical treatment.
C-type aortic coarctation
One of the main objectives of surgical treatment for Stanford type A coarctation is to eliminate the primary rupture of the aortic intima and reduce the pseudoluminal pressure, so the location of the primary rupture is one of the important factors in determining the surgical approach. According to the current international reports on the treatment results and the author’s experience, the author believes that for those whose primary rupture is in the aortic arch or distal to the arch, only performing ascending aortic replacement is not sufficient to reduce the pseudoluminal pressure and will increase the risk of reoperation of the patient. Therefore, a primary rupture in the aortic arch or distal arch with retrograde dissection of the entrapment involving the ascending aorta or the aortic root is classified as complex, meaning that such patients should undergo arch replacement.
Aortic entrapment leading to aortic arch lesions (e.g., aneurysm, giant pseudolumen, pseudoaneurysm, etc.) and/or cephalic vessels already involved by the entrapment are indications for total arch replacement, and they are also classified as complex.
Aortic coarctation due to genetic disorders (e.g., Marfon syndrome) is more unusual. In these patients, the possibility of postoperative residual aneurysmal changes and recurrence of the entrapment is very high, and therefore they are also classified as complex lesions. This suggests that physicians need to take a more aggressive approach to the treatment of patients with type A entrapment diagnosed as hereditary disease, aiming for full arch replacement at the first surgery to reduce the reoperation rate and the difficulty of reoperation.
The surgical approach is more complex for type C lesions, all of which require full arch replacement, and therefore need to be performed in centers with extensive treatment experience to achieve better outcomes.
S-type aortic coarctation
The treatment of S-type aortic coarctation is simpler and can be performed with ascending aortic replacement or partial arch surgery, which can be promoted to primary hospitals with certain cardiac surgery capabilities.