FLOPPY MITRAL VALVE, MITRAL VALVE PROLAPSE, AND THE MITRAL VALVE
A simple method of preserving the chordae during mitral valve replacement
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A Simple Method Of Preserving The Chordae During Mitral Valve Replacement Andrew Hodge, FRACS Cardiothoracic Surgical Unit, Royal Perth Hospital, Perth. Western Australia, Australia I t is common practice to preserve the chordae to the posterior mitral cusp whenever it is difficult to re- sect this cusp during mitral valve replacement. This has the advantage of better preserving ventricular function by retaining the attachment of the papillary muscle to the atrioventricular ring via the chordae. Experimental work suggests that preserving chordal attachments to the anterior cusp further im- proves peri-operative ventricular function’. The tech- nique described here is a simple method of preserving all chordae during the insertion of a mitral prosthesis. Method The principal of chordal preservation requires the placement of pledgetted mattress sutures with the pledgets on the atria1 side of the annulus, so as to draw the chordae against the endocardium between the papillary muscle attachment and the AV ring. For valves with very long chordae, the needle is passed beneath the leading edge of the cusp (Fig. 1) Fig. 1. Procedure for suture insertion in valves with long chordae (LA, left atrium; LV, left ventricle). Presented at the Gold Coast RACS-ASCTS Cardiothoracic Surgi- cal Meeting, October, 1991. and the excess cusp is folded up into the atrium around the periphery of the prosthesis (Fig. 2). Fig. 2. Procedure for use with valves with long chordae: appear- ance after tying sutures. Stenotic valves with short chordae may require measures to produce an adequate orifice without compromising the chordal attachments. This can usu- ally be achieved by splitting each commissure almost to the annulus, and by dividing the anterior cusp. The anterior cusp is incised from the centre of the leading edge to the annulus (Fig. 3). Sometimes 2 such inci- sions are made. Occasionally these incisions are com- bined with one or more incisions in the posterior cusp from the leading edge to annulus. The principle of suture placement in valves with short chordae is pre- cisely the same as for long chordae, although where chordae are very short the needle may need to be passed through the cusp itself (Fig. 4). The choice of prosthesis is important. The valve occluder should not be able to impinge on any loose valvular tissue. Hence it is necessary to employ a cen- tral flow or low profile valve. All bioprostheses are suitable for use with this procedure as is the bileaflet St Jude Medical mechanical prosthesis. Disc move- ment must be checked prior to closure of the atrio- tomy. Any small tags of tissue impeding disc move- movement can then be resected through the open prosthesis. 44
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Transcript of A simple method of preserving the chordae during mitral valve replacement
A Simple Method Of Preserving The Chordae During Mitral Valve Replacement
Andrew Hodge, FRACS
Cardiothoracic Surgical Unit, Royal Perth Hospital, Perth. Western Australia, Australia
I t is common practice to preserve the chordae to the posterior mitral cusp whenever it is difficult to re- sect this cusp during mitral valve replacement. This has the advantage of better preserving ventricular function by retaining the attachment of the papillary muscle to the atrioventricular ring via the chordae.
Experimental work suggests that preserving chordal attachments to the anterior cusp further im- proves peri-operative ventricular function’. The tech- nique described here is a simple method of preserving all chordae during the insertion of a mitral prosthesis.
Method
The principal of chordal preservation requires the placement of pledgetted mattress sutures with the pledgets on the atria1 side of the annulus, so as to draw the chordae against the endocardium between the papillary muscle attachment and the AV ring.
For valves with very long chordae, the needle is passed beneath the leading edge of the cusp (Fig. 1)
Fig. 1. Procedure for suture insertion in valves with long chordae (LA, left atrium; LV, left ventricle).
Presented at the Gold Coast RACS-ASCTS Cardiothoracic Surgi- cal Meeting, October, 1991.
and the excess cusp is folded up into the atrium around the periphery of the prosthesis (Fig. 2).
Fig. 2. Procedure for use with valves with long chordae: appear- ance after tying sutures.
Stenotic valves with short chordae may require measures to produce an adequate orifice without compromising the chordal attachments. This can usu- ally be achieved by splitting each commissure almost to the annulus, and by dividing the anterior cusp. The anterior cusp is incised from the centre of the leading edge to the annulus (Fig. 3). Sometimes 2 such inci- sions are made. Occasionally these incisions are com- bined with one or more incisions in the posterior cusp from the leading edge to annulus. The principle of suture placement in valves with short chordae is pre- cisely the same as for long chordae, although where chordae are very short the needle may need to be passed through the cusp itself (Fig. 4).
The choice of prosthesis is important. The valve occluder should not be able to impinge on any loose valvular tissue. Hence it is necessary to employ a cen- tral flow or low profile valve. All bioprostheses are suitable for use with this procedure as is the bileaflet St Jude Medical mechanical prosthesis. Disc move- ment must be checked prior to closure of the atrio- tomy. Any small tags of tissue impeding disc move- movement can then be resected through the open prosthesis.
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AustralAs J Cardiac Thorac Surg 1992; l(2): pp.44-5 Hodge Preserving the chordae
Fig. 3. Incisions to produce an adequate mitral orifice for valve insertion in stenotic valves without compromising chordal attachments
Results
Seven prostheses (27mm-31mm) were inserted for mitral stenosis and 24 prostheses (28mm-33mm) for mitral regurgitation. All were anticoagulated to maintain the INR coagulation index between 2.5 and 3.5. One patient died from multi-organ failure. There were no instances of post-operative prosthetic dys- function or emboli, no para-prosthetic leaks and only one episode of subacute bacterial endocarditis at 30 months. One patient developed a left ventricular out- flow tract gradient secondary to systolic anterior mo- tion of the anterior cusp, but did not require further surgery. This sequel is avoidable by appropriate suture placement.
References
Fig. 4. Procedure for suture placement in valves with short chordae.
1. Hanson DE, Cahill PD, DiCampli WM, et al. Valvular- ventricular interaction: importance of the mitral apparatus in canine left ventricular systolic performance. Circulation 1986; 73:1310-20.
2. Hansen DE, Cahill PD, Derby GC, Miller DC. Relative con- tributions of the anterior and posterior mitral chordae ten- dineae to canine global left ventricular systolic function. J Thorac Cardiovasc Surg 1987; 93:45-55.
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