logo

Home  ||   Editorial Board  ||  Related Links ||  News & Events ||   Rights & Permissions   ||  Contact us  
February 27, 2017
Valve Analysis Functional Classification

Pathophysiological Triad

The understanding of mitral valve pathology is facilitated by the use of the "pathophysiological triad" described by Carpentier.

The pathophysiological triad is composed of etiology (cause of the disease), valve lesions (resulting from the disease) and valve dysfunction (resulting from the lesions). These distinctions are relevant because long-term prognosis depends on etiology, whereas treatment strategy and surgical techniques depend on valve dysfunctions and lesions respectively.

Image Place Holder


Functional Classification

Carpentier's functional classification of mitral valve disease is used to describe the mechanism of valvular dysfunction. This classification is based on the opening and closing motions of the mitral leaflets.

Image Place Holder



Valvular dysfunction may present four functional types in the setting of mitral regurgitation. Patients with type I dysfunction have normal leaflet motion with the free edges of the leaflets positioned 5 to 10 mm below the plane of the annulus. Mitral regurgitation in these patients is due to annular dilatation, or leaflet perforation or tear. There is an increased leaflet motion in patients with type II dysfunction with the free edge of one or more leaflets overriding the plane of the annulus during systole (leaflet prolapse). The most common lesions leading to type II dysfunction are chordae elongation or rupture, and papillary muscle(s) elongation or rupture.

Patients with type IIIa dysfunction have a restricted leaflet motion during both diastole and systole. The most common lesions are leaflet thickening / retraction, chordae thickening / shortening or fusion, and commissural fusion encountered in rheumatic valve disease. Mitral regurgitation is usually associated with varying degrees of mitral stenosis. The mechanism of mitral regurgitation in type IIIb dysfunction is restricted leaflet motion during systole. Left ventricular enlargement leading to apico-lateral papillary muscle displacement and chordae tethering causes this type of valve dysfunction.

Image Place Holder
From Carpentier A, Adams DH, Filsoufi F. Carpentier's Reconstructive Valve Surgery. Saunders (Elsevier), 2010


 


The functional classification is further refined by segmental valve analysis which allows the precise localization of leaflet dysfunction which is of significant importance while performing reconstructive surgery.

The mitral valve is divided into 8 segments. Antero-lateral and postero-medial commissures are two segments. Two indentations on the posterior leaflet divide this structure into 3 anatomically distinct scallops. The three scallops of the posterior leaflet are identified as P1 (anterior scallop), P2 (middle scallop), and P3 (posterior scallop). The three corresponding segments of the anterior leaflet are named A1 (anterior segment), A2 (middle segment), and A3 (posterior segment).

Image Place Holder
From Carpentier A, Adams DH, Filsoufi F. Carpentier's Reconstructive Valve Surgery. Saunders (Elsevier), 2010
Image Place Holder
From Carpentier A, Adams DH, Filsoufi F. Carpentier's Reconstructive Valve Surgery. Saunders (Elsevier), 2010

Preoperatively, the functional classification and segmental analysis allow the echocardiographer to determine the precise localization of valvular dysfunction in patients with mitral valve disease. Intraoperatively, it enables the surgeon to proceed to a full analysis of valvular lesions in the segments where a dysfunction has been determined.

Image Place Holder
From Carpentier A, Adams DH, Filsoufi F. Carpentier's Reconstructive Valve Surgery. Saunders (Elsevier), 2010
Image Place Holder
From Carpentier A, Adams DH, Filsoufi F. Carpentier's Reconstructive Valve Surgery. Saunders (Elsevier), 2010


 

Valvular dysfunctions and corresponding lesions and etiologies are summarized here. It is remarkable to notify the contrast between the complexity of valvular lesions and the simplicity of resulting valvular dysfunction(s).

Image Place Holder

 

Addendum
Several varieties of prolapse require additional nosologic clarification:

Near prolapse
: A condition in which the free edge of the leaflet approaches the plane of the annulus without overriding it during systole. Leaflet apposition is not perfect; there is, however, no valvular regurgitation. This condition can worsen overtime leading to leaflet prolapse and significant mitral regurgitation.

Pseudo prolapse
: A condition in which the free edge of the anterior leaflet is above the free edge of the posterior leaflet without overriding the plane of the annulus. Seen in type IIIb dysfunction, the jet of mitral regurgitation is posteriorly directed on echocardiography.

Billowing leaflet
: Defined by the systolic protrusion of the belly of the leaflet into the left atrium due to excess leaflet tissue while the free edge remains below the plane of the annulus. Seen in patients with Barlow's disease, billowing leaflet(s) does not cause valvular regurgitation. It can, however, be complicated with leaflet prolapse secondary to chordae elongation/rupture, leading to mitral regurgitation.

 

 

 


Top

Transesophageal Echocardiography


Announcements