Pulmonary Valve Replacement

Transcription

1 Pulmonary Valve Replacement with Fascia Lata J. C. R. Lincoln, F.R.C.S., M. Geens, M.D., M. Schottenfeld, M.D., and D. N. Ross, F.R.C.S. ABSTRACT The purpose of this paper is to describe a technique of fashioning an unsupported semilunar fascia lata valve contained in a tube for insertion in the pulmonary position. The results of our experience with this valve were unsatisfactory, and we do not recommend its use. A 3-year follow-up has shown the benefit of replacing a diseased aortic valve with a pulmonary autograft [2]; to date, 101 of our patients have had pulmonary valve replacement with a processed homograft. Recently the use of both free and mounted fascia lata valves in the aortic and pulmonary positions has indicated that advantages may be gained from the use of this tissue [3-51. Because of this experience it seemed logical to replace both the aortic and pulmonary valve with autologous tissue. Clinical Material and Methods Fourteen adult patients with severe acquired aortic valve disease had their aortic valve replaced with a pulmonary autograft and their pulmonary valve reconstructed with a fascia lata valve. Normothermic cardiopulmonary bypass was used for all patients. Four patients had severe aortic regurgitation and 7 patients had aortic stenosis with gradients of between 50 and 100 mm. Hg. Three patients had combined stenosis and regurgitation. The technique of replacing the patient s aortic valve with a pulmonary autograft has been previously described by one of us [2]. The method of inserting the fascia lata pulmonary autograft in no way differs from that of placing a homograft valve at the same site. FABRICATING THE FASCIA LATA PULMONARY VALVE A piece of fascia lata approximately 8 x 6 cm. is removed from the patient s thigh and cleaned of connective tissue. Two pieces of fascia lata (No. 1 and 2) are then cut to shape around sterile cardboard patterns to dimensions predetermined according to the size of the patient. The dimensions are given in Table 1. The sites of the three commissures are marked on From the National Heart Hospital, London, England. Accepted for publication June 4, Address reprint requests to Dr. Lincoln, Brompton Hospital, London S.W.3, England. lo4 THE ANNALS 01; THORACIC SURGERY

2 Pulmonary Valve Replacement with Fascia Lata TABLE 1. DIMENSIONS FOR FABRICATING FASCIA LATA PULMONARY VALVES Internal Diameter (mm.) Dimensions A B C D E F fascia lata 1 with fine marker threads, and the lines of the commissures on fascia lata 2 are also indicated with marker threads, these being very important for correct placement and ease of orientation of the two pieces of fascia lata (Fig. 1A). The piece of fascia lata 1 is then placed in a special stretcher allowing access to both sides of the sheet of tissue while also rendering it tight (Fig. 1B). Fascia lata 2 is then placed upon 1, and with a running backstitch suture of 5-0 Mersilene it is sutured at the site of two commissures, a-a and b-b (Fig. 2). The fascia lata is then removed from the stretcher, and the third commissure is completed and sutured to c-c. The piece of fascia lata 1 is then sutured edge to edge, thus completing the tube. At this stage the valve is turned inside out and placed over the operator s index finger, and the base of each semilunar cusp is sutured to the outer tube of the fascia lata (Fig. 3, left). On completing these sutures the valve is turned right side out, and a horizontal mattress suture is placed at the top of each commissure to encourage apposition of the cusps. The valve is then ready for use (Fig. 3, right). The distal pulmonary artery-to-valve anastomosis is first constructed when, with bronchial backflow, the cusps become competent and fill. The proximal valve-to-right ventricle anastomosis is then completed. Upon discontinuation of cardiopulmonary bypass the leaflets of this fabricated pulmonary valve can be seen to open and close in systole and diastole through the thin wall of the fascia lata tube. Results The early results of this technique appeared to be satisfactory [71. Angiographic examination of 1 patient three months after the operation demonstrated the valve to be competent, and the cusp mechanism was clearly seen (Fig. 4). The late results, however, have not been satisfactory [9]. Seven patients have been followed from one to eleven months, and the clinical data can be VOL. 13, NO. 2, FEBRUARY,

3 LINCOLN ET AL. A 2 B FIG. 1. (A) Two pieces of fascia lata (1 and 2) are cut to shape and marker threads placed at the site of the three commissures of the valve. The piece of fascia lata 1 is placed in the stretcher (B) to allow placement of fascia lata 2. seen in Table 2. Within three months of the operation, 3 patients were noted to have signs of right ventricular obstruction, and by six months, 4 patients had early diastolic murmurs with radiological evidence of right atrial and ventricular enlargement. Three of the 7 patients have been investigated by cardiac catheterization, and 2 of them showed evidence of right ventricular hypertension. Information on the remaining 4 patients is not yet available from their referring physicians. Three patients are awaiting investigation, and all have clinical signs of right ventricular hypertrophy. Eleven months after his operation, Patient 3, who had severe right heart failure, underwent reoperation, at which time the fascia valve in the pulmonary position was found to be narrowed and shrunken and there was no evidence of three valve cusps. This valve was successfully replaced with an aortic homograft. 106 THE ANNALS OF THORACIC SURGERY

4 Pulmonary Valve Replacement with Fascia Lata FIG. 2. (Left) Fascia lata 2 is secured to fascia lata 1 at the site of the commissures a-a' and b- b'. (Middle) The fascia lata is removed from the stretcher, and the third commissure is completed and attached to c-c'. (Right) Fascia lata 1 is sutured edge to edge, completing the tube. Comment The early function of these fascia lata pulmonary autografts appeared to be satisfactory. The ease of construction and the obvious advantages of a valve made from readily available autologous tissue, thus precluding the difficulties of availability and size of homograft material, were attractive features. It was easier to achieve hemostasis at the suture lines with fascia lata valves than it was when homografts were employed. The normal discrepancy between the aortic and pulmonary roots must be taken into account when making the valve [l]. The clinical evidence suggests that these valves malfunction as early as three months after implantation and that severe stenosis or incompetence ensues. The early angiographic study in 1 patient one month after implantation showed that the valve was widely patent and competent, but eleven months later there was severe regurgitation. It is evident that the fascia lata shrinks and does not remain viable, and this has been corroborated by a histological study done by one of us IS]. Contraction of fascia lata has also been shown to occur in fascia lata valves mounted on a frame and used in the mitral and tricuspid positions El. FIG. 3. (Left) The valve is turned inside out over the index finger of the operator, and the base of each semilunar cus$ is attached to the outer tube. (Right) The valve is removed, and horizontal mattress sutures are $laced at the top of each commissure.

5 TABLE 2. DIAGNOSIS AND POSTOPERATIVE DATA ON 7 PATIENTS WITH FASCIA LATA RECONSTRUCT10 I F THE RIGHT VENTRICULAR OUTFLOW TRACT Time Pressure (mm. Hg) Age at (mo.) of Patient Diag- Operation Postop. RA PI No. nosis (yr.) Invest. RHF PCP PAP RVP A (0-3) JVP 1 AS Clin. + 2 AS Asystole CHB......? 3 AR / T? /? AR / AS No. rt. heart pressure taken AR AS RHF = right heart failure; PCP = pulmonary capillary pressure; PAP = pulmonary artery pressure; RVP = right ventricular pressure; RA A =right atrial pressure A wave; PI = pulmonary incompetence, graded 0 to 3; JVP = jugular venous pressure with high A waves; AS =aortic stenosis; AR = aortic regurgitation; CHB =complete heart block. + +

6 Pulmonary Valve Replacement with Fascia Lata A B FIG. 4. Posteroanterior (A) and lateral (B) pulmonary artery angiograms of a patient in whom a fascia lata pulmonary valve has been inserted. The valve sinuses and cusps can be clearly seen. The results with these fascia lata pulmonary autografts were unsatisfactory, and we do not recommend their use. The technique of constructing the valve could be useful with a more suitable material, when available. Aortic homog-rafts would still appear to be the most suitable material for reconstructing the right ventricular outflow tract or pulmonary artery. References 1. Eckner, A. O., Brown, W., Davidson, D., and Glagon, S. Dimensions of normal human hearts after standard fixation by controlled pressure coronary perfusion. Arch. Pathol. 88:497, Gonzalez-Lavin, L., Geens, M., and Ross, D. N. Pulmonary valve autograft for aortic valve replacement. J. Thorac. Cardiovasc. Surg. 60:322, Ionescu, M. I., and Deac, R. Fascia lata composite graft for right ventricular outflow tract and pulmonary artery reconstructions. Thorax 25:423, Ionescu, M. I., Deac, R., Grimshaw, V. A., Taylor, S. H., Whittaker, W., and Wooler, G. Autologous fascia lata for heart valve replacement. Thorax 25: 888, Ionescu, M. I., and Ross, D. N. Heart valve replacement with autologous fascia lata. Lancet 2:335, Lincoln, J. C. R., Balcon, R., Emanuel, R., MacDonald, L., Muir, J., Ross, D. N., Somerville, J., and Taylor, J. Mitral valve replacement with fascia lata (Proceedings of the VI World Congress on Cardiology). Cardiovasc. Res. vol 200, Lincoln, J. C. R., Geens, M., Ross, D. N., and Ionescu, M. I. Replacement of the pulmonary valve and pulmonary artery with fascia lata. Br. Heart J. 33:146, Lincoln, J. C. R., Riley, P. A., Revignas, A., Geens, M., and Ross, D. N. The viability of autologous fascia lata in heart valve replacements. Thorax 26:277, Ross, D. N., and Somerville, J. Fascia lata reconstruction of the right ventricular outflow tract. Lancet 1:942, VOL. 13, NO. 2, FEBRUARY, 1972 log