Ten-year experience of chordal replacement with expanded polytetrafluoroethylene in mitral valve repair.
BACKGROUND
Mitral valve repair is the procedure of choice to correct mitral regurgitation (MR). Although chordal replacement with expanded polytetrafluoroethylene (ePTFE) has been widely accepted to repair anterior mitral prolapse and other difficult situations, the long-term results of the repair and the fate of ePTFE have not been delineated.


RESULTS
From July 1988 to April 1999, 74 patients (49 males, 25 females) aged 17 to 77 years (mean age 55. 3+/-14.8 years) underwent mitral valve repair with chordal replacement with ePTFE. The follow-up period was from 6 months to 11. 3 years (mean 4.6+/-3.2 years). The causes of MR were degenerative in 65 patients (88%) and infective in 9 (12%). Three patients had active infective endocarditis. Valve lesions were anterior in 35 patients, posterior in 10, and both anterior and posterior in 29. Various procedures for plasty of leaflets were necessary in 37 patients (50%). Atrial fibrillation was associated in 38 patients (51%), and the maze procedure has been performed in a selected group of 30 patients (41%) since July 1992. There was 1 in-hospital death (1.4%) and 3 late cardiac deaths (4.1%). More than moderate MR developed in 12 patients (17%) during the follow-up period. Three of these patients required early reoperation within 1 year due to hemolysis. Two patients underwent mitral valve replacement at 6 and 8 years after repair, respectively. The actuarial reoperation-free rates at 5 and 10 years were 94.3+/-2.8% and 81.7+/-9.1%, respectively. Sinus rhythm was restored in 21 patients (70%) with the maze procedure. There was only 1 thromboembolic episode (0. 3%/patient-y) in a patient with atrial fibrillation who did not undergo the maze procedure. Event-free survival rates as assessed by the freedom from cardiac death, thromboembolism, reoperation, and anticoagulation-related hemorrhage at 5 and 10 years were 91.3+/-3. 4% and 71.6+/-9.7%, respectively. There was no relationship between recurrent MR and the change of ePTFE. Structural analysis of the ePTFE resected during reoperation revealed no calcification and showed remaining flexibility and pliability. Protein infiltration was observed in the ePTFE, and collagenous proliferation was recognized at the site of fixation to the valve leaflet and the papillary muscle. The surface of the ePTFE was completely endothelialized, which may induce antithrombogenicity.


CONCLUSIONS
The long-term durability and biological adaptation of ePTFE as artificial chordae for mitral valve repair of MR were proved for >10 years.
Kobayashi
J
J
Department of Cardiovascular Surgery, National Cardiovascular Center, Osaka, Japan. jkobayas@hsp.ncvc.go.jp
Sasako
Y
Y
Bando
K
K
Minatoya
K
K
Niwaya
K
K
Kitamura
S
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications; D001672:Biocompatible Materials; D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000379:methods; D002815:Chordae Tendineae / Q000601:surgery*; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000601:surgery*; D008944:Mitral Valve Insufficiency / Q000150:complications / Q000000981:diagnostic imaging / Q000235:genetics / Q000601:surgery*; D011138:Polytetrafluoroethylene; D019736:Prostheses and Implants; D012086:Reoperation / Q000706:statistics & numerical data; D015996:Survival Rate; D013995:Time; D016896:Treatment Outcome
D001672:Biocompatible Materials; D011138:Polytetrafluoroethylene