Commissural area
The anterior and the posterior commissures are not at all alike. The anterior commissure is rarely involved, mostly as it is well supported by the trigone. On the contrary, the Posterior Commissure (PC) is free of any support and most likely its involvement is underestimated. There are obvious prolapses of the PC, and there are billowing which may seem innocuous but may be favoring with time a recurrent regurgitation due to its weakness.
Given that this area is all supported by many chordae arising from the posterior papillary muscle displacing downwards the adequate head, may correct very easily any posterior commissural prolapse. We have described this idea as a new surgical technique that we called Papillary Muscle Repositioning (PMR) in 2006 [7]. In our experience it is the method of choice to treat AL and PC prolapse, due to elongated chordae and irrespectively of the location of the lesion, with excellent clinical and echocardiographic long-term results.
Alternatively, artificial chordae cannot easily be used as it is the area of the valve which has as the greatest number of chordae. Many surgeons, referring to Carpentier use what they call a commissural plasty or “commissuroplasty “which is a complete closure of the posterior commissure, suturing together A3 to P3. This technique is very fast and simple. It does not promote any coaptation. Whether it is efficient in terms of durability remains to be confirmed. As a comment, Carpentier never closed the PC in Barlows , but described a similar technique in rheumatic patients, for whom the PC required to be reconstructed after complete decalcification reaching the annulus . The PC area was reconstructed by using inverted single sutures for 6 to 10 mm, thereby recreating the PC.