**5. Lesions**

Any of the previously listed disease can cause lesions affecting one or several components of the heart valves: the annulus, the leaflets, and the supporting structures (Table #2).


Table 2. Valvular Lesions.

Mitral Valve Subvalvular Apparatus Repair with Artificial Neochords Application 9

Marfan's syndrome of the mitral valve is characterized by excess tissue, thickened leaflets, and a dilated annulus. Patients with Marfan syndrome have a shortened life expectancy because of cardiovascular complication, 80% of them developing mitral valve regurgitation.

Fibroelastic deficiency occurs mostly in the elderly with a short history of valvular dysfunction. The leaflets are transparent, and except for the prolapsing segment there is no excess tissue. The chordae are thin, fragile, and elongated. The annulus is dilated and often

Table 3. Кеу differences between Barlow,s disease and fibroelastic deficiency

valve disease is presented in group of 1072 patients as follows (Table #4).

Table 4. Pathologic anatomy of degenerative mitral valve disease (n = 1072).

According to A. Marc Gillinov and coworkers, pathologic anatomy of degenerative mitral

**7.4 Pathologic anatomy of degenerative mitral valve disease** 

**7.2 Marfan's disease** 

**7.3 Fibroelastic deficiency** 

infiltrated with calcium (Table #3).

## **6. Valve dysfunction: The «Functional classification»**

The pioneering cardiac surgeon Alain Carpentier, MD, PhD, developed a functional classification to reflect the underlying pathological changes that contributed to MR (*Carpentier A. 1983)* (Figure 4). As described in this classification, type I MR is characterized as normal leaflet motion but with annular dilatation or leaflet perforation; type II lesions are related to leaflet prolapse and may be caused by myxomatous disease, such as chord rupture or elongation, or by papillary muscle rupture or elongation; and type III lesions are caused by restricted leaflet motion. Type IIIA is typically caused by rheumatic valve disease with normal ventricular motion and subvalvular fibrosis and calcification; type IIIB is typically caused by ischemic or idiopathic cardiomyopathy with impaired ventricular function and dilation but a "normal" morphology to the leaflets, chords, and papillary muscles, frequently with restriction at the P3 segment. Type I MR may occur with billowing myxomatous leaflets but without elongated chordae and prolapse (type II), if extensive annular dilatation leads to inadequate leaflet coaptation (*Fornes P et al., 1999).* 

Fig. 4. Functional classification.

#### **7. Degenerative valvular disease**

The tree main types of degenerative valvular disease are Barlow,s disease, fibroelastoc deficiency, and Marfan,s disease.

#### **7.1 Myxomatous mitral valve disease (Barlow's disease)**

Barlow's disease is the most frequent degenerative valvular disease with a prevalence of 4% to 5 % in the general population, generally appears early in life. Patients present with a prolonged history of a murmur, thickened leaflets, substantial excess tissue, and a dilated annulus, which may be calcified (1). Chordae may be elongated and thinned. Often isolated ruptures are present, contributing to the focal prolapse. Classically, the most common abnormality is focal enlargement of the posterior central scallop (P2) with an associated ruptured chorda. Mills et al. comparing unileaflet versus bileaflet prolapse, found that patients with unileaflet prolapse were younger and had a higher incidence of flail leaflets (3). Patients with bileaflet prolapse were less likely to be hypertensive and had mechanically stronger chordae though leaflet strength was similar to patients with unileaflet prolapse.

#### **7.2 Marfan's disease**

8 Front Lines of Thoracic Surgery

The pioneering cardiac surgeon Alain Carpentier, MD, PhD, developed a functional classification to reflect the underlying pathological changes that contributed to MR (*Carpentier A. 1983)* (Figure 4). As described in this classification, type I MR is characterized as normal leaflet motion but with annular dilatation or leaflet perforation; type II lesions are related to leaflet prolapse and may be caused by myxomatous disease, such as chord rupture or elongation, or by papillary muscle rupture or elongation; and type III lesions are caused by restricted leaflet motion. Type IIIA is typically caused by rheumatic valve disease with normal ventricular motion and subvalvular fibrosis and calcification; type IIIB is typically caused by ischemic or idiopathic cardiomyopathy with impaired ventricular function and dilation but a "normal" morphology to the leaflets, chords, and papillary muscles, frequently with restriction at the P3 segment. Type I MR may occur with billowing myxomatous leaflets but without elongated chordae and prolapse (type II), if extensive

The tree main types of degenerative valvular disease are Barlow,s disease, fibroelastoc

Barlow's disease is the most frequent degenerative valvular disease with a prevalence of 4% to 5 % in the general population, generally appears early in life. Patients present with a prolonged history of a murmur, thickened leaflets, substantial excess tissue, and a dilated annulus, which may be calcified (1). Chordae may be elongated and thinned. Often isolated ruptures are present, contributing to the focal prolapse. Classically, the most common abnormality is focal enlargement of the posterior central scallop (P2) with an associated ruptured chorda. Mills et al. comparing unileaflet versus bileaflet prolapse, found that patients with unileaflet prolapse were younger and had a higher incidence of flail leaflets (3). Patients with bileaflet prolapse were less likely to be hypertensive and had mechanically stronger chordae though leaflet strength was similar to patients with

annular dilatation leads to inadequate leaflet coaptation (*Fornes P et al., 1999).* 

Fig. 4. Functional classification.

deficiency, and Marfan,s disease.

unileaflet prolapse.

**7. Degenerative valvular disease** 

**7.1 Myxomatous mitral valve disease (Barlow's disease)** 

**6. Valve dysfunction: The «Functional classification»** 

Marfan's syndrome of the mitral valve is characterized by excess tissue, thickened leaflets, and a dilated annulus. Patients with Marfan syndrome have a shortened life expectancy because of cardiovascular complication, 80% of them developing mitral valve regurgitation.

#### **7.3 Fibroelastic deficiency**

Fibroelastic deficiency occurs mostly in the elderly with a short history of valvular dysfunction. The leaflets are transparent, and except for the prolapsing segment there is no excess tissue. The chordae are thin, fragile, and elongated. The annulus is dilated and often infiltrated with calcium (Table #3).

Table 3. Кеу differences between Barlow,s disease and fibroelastic deficiency

#### **7.4 Pathologic anatomy of degenerative mitral valve disease**

According to A. Marc Gillinov and coworkers, pathologic anatomy of degenerative mitral valve disease is presented in group of 1072 patients as follows (Table #4).

Table 4. Pathologic anatomy of degenerative mitral valve disease (n = 1072).

Mitral Valve Subvalvular Apparatus Repair with Artificial Neochords Application 11

with removal of the mitral apparatus. Each procedure has its advantages and disadvantages, and therefore, the indications for each procedure are somewhat different (Bonow et al.,

In most cases, MV repair is the operation of choice when the valve is suitable for repair and appropriate surgical skill and expertise are available. This procedure preserves the patient's native valve without a prosthesis and therefore avoids the risk of chronic anticoagulation (except in patients in atrial fibrillation) or prosthetic valve failure late after surgery. Additionally, preservation of the mitral apparatus leads to better postoperative LV function and survival than in cases in which the apparatus is disrupted. Improved postoperative function occurs with repair because the mitral apparatus is an integral part of the left ventricle that is essential for maintenance of normal shape, volume, and function of the left ventricle. However, MV repair is technically more demanding than MV replacement, may require longer extracorporeal circulation time, and may occasionally fail. In USA (Savage et al., 2003) and Europe (Lung et al., 2003) the valve with MV regurgitation is repaired in only 50% of cases. Valve morphology and surgical expertise are of critical importance for the success of valve repair. The reoperation rate after MV repair is similar to the reoperation rate after MV replacement. There is a 7% to 10% reoperation rate at 10 years in patients undergoing MV repair, usually for severe recurrent MR. Approximately 70% of the recurrent MR is thought to be due to the initial procedure and 30% to progressive valve disease. The reoperation rate is lower in those patients who had the initial operation for posterior leaflet abnormalities than in those who had bileaflet or anterior leaflet abnormalities. In many cases, the type of operation, MV repair versus replacement, is important in timing surgery. In fact, although the type of surgery to be performed is never actually established until the operation, many situations lend themselves to preoperative prediction of the operation that can be performed. This prediction is based on the skill and experience of the surgeon in performing repair and on the location and type of MV disease that caused the MR. Nonrheumatic posterior leaflet prolapse due to degenerative MV disease or a ruptured chordae tendineae can usually be repaired using a resection of the portion of the valve and an annuloplasty. Involvement of the anterior leaflet or both anterior and posterior leaflets diminishes the likelihood of repair because the operation requires other interventions, such as chordal shortening, chordal transfer, and innovative anatomic repairs. Consequently, the skill and experience of the surgeon are probably the most

important determinants of the eventual operation that will be performed.

According to M. Scorsin (Scorsin et al., 2010), in 90% cases of posterior mitral valve prolapse is repaired with standart techniques: 1 - quadrangular \ triangular resection + placation of annulus, sliding, folding; 2- artificial chordate sutures. Current techniques for anterior leaflet prolapsed include valvular and subvalvular approach. In turn, valvular approach include papillary muscle placation, chordal shortening, leaflet resection, transposition of chordate. Subvalvular approach include artificial chordate. Among several repair techniques chordal replacement using ePTFE sutures has been introduced into clinical practise by Frater. There are several advantages to use of ePTFE suture for chordal replacement preservation of native valve anatomy, physiological leaflet motion and creation of large

**8.2 Surgical approach** 

2008).
