**2.12. Surgery of the valvular mitral prolapse in the SM**

The mitral and tricuspid affectations constitute the most frequents cardiac finding in the MFS, though the tricuspid rarely has repercussion. The alterations of the mitral connective tissue carry to the growth in a myxoid aspect, with high content of air in its interior, though the histology and the morphology of the mitral valve in patients with MFS are different from the classic myxoid valve disease. In the MFS the leaflets, though thicker than normal, they are longer and thinner than the mixoides ones and with minor celularity.

Patients with MFS present more frequently affectation of both leaflets or the anterior one, which, together with the laxity of the valvular tissue, makes more frequent the prevalency of mitral prolapse in patients with MFS compared with the healthy population (50-80% opposite to 2,4%). In these patients the prolapse can produce moderate mitral regurgitation or major up to 25 % of the cases. It is also typical the trend to the early calcification of the mitral ring, which constitutes a minor diagnostic criteria.

In the most serious forms of the MFS, which begin in the first years of life, the mitral affectation can cause cardiac heart failure and pulmonary hypertension, with very

unfavorable surgical results in younger than 2 years old, being an important reason for mortality in children with MFS. In teenagers and adults the surgical repair of the severe mitral severe regurgitation is associated with a high events free survival.

The mitral isolated surgery is infrequent, and in the majority of the occasions we carry out combined conservative procedures on the aorta and the mitral valves to avoid the anticoagulation therapy.

The extensive calcification of the mitral ring is the main contraindication for the mitral repair in the MFS. It is important to insist that not repair severe mitral regurgitation, concerns adversely the aortic hemodynamic stress and the ventricular function in the MFS.

In a similar way to the case of the aortic valve, the classic method used in patients with severe mitral regurgitation is the valve replacement, usually with mechanical prosthesis. Nevertheless, and given the high morbidity that these can produce over the years because of the thromboembolic and infectious events, the conservative mitral valve techniques are the gold standard of the mitral surgery, with long-term results similar to the ones obtained in patients without Marfan's syndrome.

Before this type of valves, the surgeon must use the whole available technical equipment and devices, being in an extensively use the PTFE's neocordae, and always associating annuloplasty rings, preferably rigidly or semi rigid. In occasions, it is used the double orifice technique, described by Alfieri, less demanding technically, though the anatomical repair methods are the ones preferred.

The immediate and long-term results are very good, with events free survival and reintervention free survival of 95 % at 10 years, specially when the early surgery is indicated.

#### **2.13. Other cardiovascular manifestations of the SM**

The expansion of the trunk of the pulmonary artery is less frequent than the aortic one, and rarely it causes dissection. In the MFS it is possible to have alterations in the atrioventricular conduction and in the ventricular repolarization (long QT, ST alterations and U waves), that might be associated with ventricular arrhythmias, but it is not clear if these changes are secondary to a primary myocardiopathie or to ventricular dilatation owed to the evolved regurgitations.

#### **3. Conclusion**

The diagnosis of Marfan syndrome is inevitably complex, due to the high variability of presentation of affected individuals, the dependence of the age in many clinical manifestations, the absence of gold standards diagnostic tests, and the wide differential diagnosis. The new Marfan syndrome diagnostic criteria are intended to facilitate a correct and early identification by professionals and improve the prognosis of these patients.

In last decades there have been significant changes in the prognosis of the Marfan syndrome. Cardiovascular management of these patients is based on three pillars aimed to increase hope and quality of life: stratification of risk, medical treatment and prophylactic aortic surgery.

Imaging techniques contribute to establish the risk of these patients and select better cases and the most appropriate time for the indication of elective surgery.

All patients should be treated early, at least with beta-blockers. Meanwhile, it will continue to evaluate new therapies aimed at stopping or even reversing the pathological changes associated with the disease.

More and more patients with Marfan syndrome will achieve more advanced stages of life, and this will mean new challenges. It will be tested the acquired knowledge and teamwork from specialized multidisciplinary units will be essential.
