Brief Case Description

The patient is a 48 year-old male who presented with shortness of breath. Physical examination was remarkable for systolic murmur of mitral regurgitation at the apex. Transthoracic echocardiography showed type II mitral dysfunction with posterior leaflet prolapse and severe mitral regurgitation. The left ventricle was normal in size and function. Echocardiography also showed minimal tricuspid regurgitation. The right ventricle was normal in size and function.

The patient was referred for reconstructive mitral valve surgery. Preoperative cardiac catheterization showed normal coronaries.

Operative Procedure

Intraoperative Transesophageal Echocardiography

Intraoperative transesophageal echocardiography confirmed the diagnosis of posterior leaflet prolapse involving the P2 segment (mid esophageal four-chamber and long axis views). Doppler echocardiography showed an anteriorly directed jet (mid esophageal two-chamber and long axis views) and mitral regurgitation was graded severe.

Mitral Valve Analysis

Following the exposure of the mitral valve, we first performed valve analysis using Carpentier's reference point technique. We confirmed the normal leaflet motion of P1 by pulling its free edge upward with a nerve hook. The P1 segment was neither prolapsing as its free edge was not overriding the plane of the mitral annulus nor restricted. Using a second hook, other valve segments were examined in a systematic manner and compared to P1 to verify if they were prolapsing. In this particular case, valve analysis confirmed the prolapse of P2 segment due to chordae elongation. There was an excess tissue of the prolapsing segment. Both indentations were normal. The anterior leaflet had normal leaflet motion with no prolapsing segments. The mitral annulus was mildly dilated.

Following this complete valve analysis, we can summarize the pathophysiological triad as follows:

Etiology: Fibroelastic deficiency

Lesions: Chordae elongation, secondary annular dilatation

Dysfunction: Type II posterior leaflet

Reconstructive Procedure

This was a case of limited prolapse of P2 segment. Therefore, we performed a triangular resection of the P2 segment.

Annular sutures were placed circumferentially to optimize the exposure of the valve. Two 4-0 stay sutures were passed at the limits of the prolapsed portion of the leaflet. Approximately 2 mm from these normal chordae, a blue marker was used to delineate the limits of the triangular resection. As a principle rule, the height of the triangle should be slightly longer than its base.

Following the limited triangular resection, the height of the leaflet remnants was about 15 mm. Leaflet continuity was restored with interrupted 5-0 monofilament sutures.

Valve analysis following reconstruction showed a similar height between reference P1 and the reconstructed leaflet segment indicating a perfect result. This was later confirmed by the saline test which showed a symmetrical line of coaptation with no residual regurgitation.

Finally, a remodeling annuloplasty was performed . We first measured the intercommissural distance using a 34 mm sizer which was the appropriate size. Second, we measured the height of the anterior leaflet. The 34 mm sizer was covering the entire anterior leaflet surface area. Therefore, a 34 mm Carpentier Edwards Physio ring was selected and implanted.

A saline test was performed and showed a symmetrical line of coaptation, parallel to the posterior aspect of the annulus.

Postbypass Transesophageal Echocardiography

Postbypass mid esophageal four-chamber and long axis views showed a competent mitral valve with no residual regurgitation.

That was further confirmed by postoperative transthoracic echocardiography. The mitral valve area by Doppler was 2.4 cm2. The mean transvalvular gradient was 4 mmHg.