Combined aortic and mitral valve surgery accounts for approximately 10-15% of all valve surgical procedures, with significantly increased mortality and perioperative risk compared to surgeries involving only one valve. Sutureless prostheses used in aortic valve replacement have demonstrated remarkable short- and long-term advantages. Among the most notable benefits are their ease of implantation and reduction in surgical times. Although the use of these sutureless prostheses in combined aortic and mitral valve surgeries has not been widely adopted or thoroughly described, there is potential that reducing ischemia and cardiopulmonary bypass times may mark a milestone in improving outcomes. In this original article, Zaheer et al. share their experience in this type of intervention and provide a detailed, step-by-step description of the most critical aspects to successfully perform this surgical technique.

1. Proper planning
   Aortic annular measurements using computed tomography or echocardiography are extremely beneficial and highly recommended to anticipate the optimal size of the Perceval prosthesis. In this context, it is important to note that both mitral repairs and replacements with prostheses are viable in combination with the Perceval prosthesis, with no conclusive evidence supporting one technique over the other.
2. Accurate assessment of the mitral-aortic distance
   Early clinical experience raised concerns that implanting a Perceval prosthesis could be counterproductive due to fears that the mitral prosthesis might interfere with the lower portion of the Perceval prosthetic ring, increasing the risk of displacement. However, lessons learned from early experience with transcatheter aortic valve implantation (TAVI) have provided a new perspective, suggesting that the mitral-aortic junction size is a critical factor. It has been established that if the distance between these structures, measured by echocardiography, is less than 9 mm, the risk of procedural failure increases. In the context of a Perceval prosthesis procedure, the article’s authors propose that to ensure procedural success, this distance should be 4 mm in the case of mitral repairs and 8-10 mm in the case of mitral replacements.
3. “Measure twice, implant once”
   In most mitral-aortic surgeries, surgeons commonly perform the complete excision of the aortic valve and the decalcification of the aortic annulus before implanting the mitral prosthesis, with an initial measurement taken at this stage. However, the final prosthesis size is likely to be smaller after the mitral prosthesis is implanted. This first measurement is the only opportunity for the sizer to freely pass through the left ventricle (LV) via the aortic annulus, allowing for a more precise and realistic measurement of the aortic annulus. After the mitral prosthesis is implanted, a second measurement of the aortic annulus is essential. At this point, it is crucial to ensure the sizer properly fits at the level of the aortic annulus. It is not useful to measure at a lower level, as the mitral prosthesis will obstruct the sizer’s passage into the LV, potentially giving the impression that a smaller prosthesis is required. Apart from this, the technique does not differ from conventional implantation.
4. Mitral first
   A fundamental principle is to avoid oversizing the mitral prosthesis, as this could reduce the size of the aortic annulus, necessitating a smaller Perceval prosthesis. Additionally, oversizing could deform the aortic annulus, increasing the risk of paravalvular or intravalvular leaks, as well as the possibility of the Perceval being deployed in a supra-annular position. When dealing with a bioprosthetic mitral valve, it is essential to ensure that none of the mitral prosthesis posts align with the left ventricular outflow tract (LVOT), as this could increase the gradient and more frequently cause insufficiency and malposition of the Perceval prosthesis. The trend toward lower-profile posts in current mitral prostheses has significantly reduced this complication. Finally, using everted sutures in the mitral prosthesis implantation (patches on the atrial side) can help preserve the length of the mitral-aortic junction, preventing its shortening and thus facilitating the subsequent release of the Perceval prosthesis.
5. Balloon catheter inflation: option and considerations
   Controlled balloon catheter inflation is a critical step allowing the Perceval bioprosthesis to expand fully, ensuring the proper positioning of the infrannular prosthetic ring within the native aortic annulus. However, some surgeons prefer to avoid this step to prevent potential prosthesis dislocation if the balloon is positioned too low, coinciding with the mitral prosthesis plane. This could result in an upward dislocation of the Perceval prosthesis into a distal position. In this context, the article does not clearly specify the technique recommended.
6. Assessment of correct release and deployment of the Perceval prosthesis
   It is crucial to verify that the prosthesis expands fully and without visible deformities upon complete deployment. It is also essential to ensure the correct orientation of the prosthetic leaflets, with each one aligning with the respective aortic sinuses. Similar to the conventional technique, there should be no visible annulus above or below the prosthetic ring. Additionally, in this particular case, after deployment, the typical clearance between the Perceval prosthesis and the mitral prosthesis is generally 1 to 3 mm, which should also be verified to confirm proper positioning.
7. Decision-making in various circumstances
   Firstly, if a problem is detected with the Perceval prosthesis, there are several solution options. If it is suspected that the aortic prosthesis is distorted due to the mitral prosthesis, this problem can be carefully addressed by applying gentle upward traction along the non-coronary sinus. In the case of an abnormal deployment and clear malposition of the prosthesis, it can be relatively easily removed using the so-called “X-movement” technique, always ensuring not to damage the aortic root during this process.

Secondly, if the problem is related to the mitral prosthesis and requires revision, it can usually be performed safely without removing the Perceval prosthesis. Unlike sutured aortic prostheses, the Perceval is flexible, facilitating visualization of the mitral area. However, in situations where additional sutures need to be placed in the anterior mitral annulus, it may sometimes be preferable to remove the Perceval prosthesis for convenience and to perform the intervention more safely.

COMMENTARY:

Double valve replacement surgery is a common procedure in our daily practice. According to databases like the STS, it represents approximately 11% of all valve operations, with the aortic and mitral valves being by far the most frequently addressed. However, it is important to highlight that the mortality associated with combined aortic and mitral valve surgery is significant, reaching around 10% as reported by the same database.

On the other hand, evidence strongly supports that shorter cross-clamp and cardiopulmonary bypass times lead to better outcomes, particularly in elderly patients or those at higher surgical risk. Registries such as SURE-AVR, along with review articles and meta-analyses we have recently discussed on this blog, have clearly demonstrated the short- and mid-term benefits of Perceval sutureless prostheses. One of the most notable and well-supported advantages of these sutureless prostheses is their ability to reduce ischemic and bypass times. This feature has garnered increasing interest among many professionals, especially in the context of multivalve surgeries, where optimizing surgical time could be of critical importance.

The literature on the use of Perceval prostheses in combined aortic and mitral valve surgery is scarce. In the most recent study with the largest sample size, Zubarevich et al. compared 46 patients who underwent surgery with conventional prostheses to 23 patients who received Perceval prostheses, with data stratification applied. The mean age was 70 years, with an average EuroSCORE of 6 points. Although surgical times were significantly reduced with the use of Perceval prostheses, this benefit did not translate into a significant reduction in morbidity and mortality.

At our hospital, CHUAC (A Coruña), we have performed a total of 64 combined aortic and mitral valve procedures since the implementation of this prosthesis. Although we have not conducted a direct comparative study with the conventional prostheses used in our center, we have observed that our ischemia and cross-clamp times remain shorter compared to the Perceval group results reported in the Zubarevich et al. study. Despite these differences in timing, it is important to note that the outcomes in terms of morbidity and mortality were very similar.

From our experience in A Coruña, we generally agree with the findings presented in the article; however, we would like to make some clarifications regarding certain steps:

• In terms of proper planning, if we anticipate that the aortic root and annulus are significantly dilated (annuli exceeding 27–29 mm), especially as determined by intraoperative transesophageal echocardiography, it may be the best decision to initially refrain from attempting to implant a Perceval prosthesis. This approach avoids the need for a high-level aortotomy, which could complicate the surgical technique required for implanting a conventional sutured prosthesis.
• Regarding the necessary distance in the aorto-mitral junction to safely implant the Perceval, we follow two fundamental criteria. First, we emphasize the importance of having an aorto-mitral “curtain” of at least 5 mm, as measured via echocardiography. Second, and even more critical, is the intraoperative visual confirmation of this distance after the mitral prosthesis has been implanted. To effectively preserve this distance after mitral valve replacement, we consider it beneficial to implant the prosthesis in an intra-annular position. Additionally, we recommend placing the sutures for the anterior mitral annulus, whenever possible, not in the true mitral annulus but in a 5-mm recess in the anterior mitral leaflet, which is prepared in advance for this purpose.
• In our department, we follow the balloon inflation procedure but emphasize two critical aspects. First, we meticulously avoid lowering the balloon catheter excessively, which prevents prosthesis dislocation toward the aorta. Second, we limit the inflation to a pressure of 4 atmospheres for a duration of less than 5 seconds, aiming to reduce the likelihood of atrioventricular blocks, as corroborated by previous publications.

Despite the need for further studies to more conclusively support the clinical benefits of the Perceval prosthesis in combined mitral valve surgery, this procedure offers a clear advantage of shorter surgical times compared to conventional prostheses. Additionally, it remains a straightforward and safe option. The article by Zaheer et al. provides valuable insights and recommendations on this surgical technique, which will undoubtedly benefit many surgeons.

REFERENCE:

Zaheer S, Quinn RD, Robich MP. The 7 Pillars for Perceval Implantation With Mitral Valve Repair or Replacement. Innovations (Phila). 2023 Jul-Aug;18(4):308-310. doi:10.1177/15569845231190877