title: Obstruction of mechanical heart valve prostheses: clinical aspects and surgical management.
abstract: One hundred patients (32 male) aged 5 months to 82 years (median 32 years) underwent 106 surgical procedures for 112 mechanical prosthetic valves obstructed by a thrombus (n = 61) or pannus (n = 7), or both (n = 44), between January 1, 1980 and December 31, 1989. The position of the obstructed prosthesis was aortic in 51 patients (48%), mitral in 49 (46%) and both aortic and mitral in 6 (6%). The types of obstructed prosthetic valves were Björk-Shiley (n = 51), St. Jude (n = 41) and Medtronic-Hall (n = 20). The time interval between valve replacement and obstruction ranged from 6 weeks to 13 years (median 4 years). Of 63% of patients in whom coagulation variables were available at the time of obstruction, 70% were receiving inadequate anticoagulant therapy. In 63% of the procedures the patient was in New York Heart Association functional class IV. Two patients underwent preoperative thrombolysis with incomplete results. Operative procedures included valve replacement (n = 81), valve declotting and excision of pannus (n = 23) and aortic valve replacement and mitral valve declotting (n = 2). The early mortality rate was 12.3% (13 patients), and there was no difference between surgery for mitral prostheses (12.2%) versus aortic prostheses (13.7%). The perioperative mortality rate was 17.5% (11 of 63 patients) in patients in functional class IV and 4.7% (2 of 43 patients) in those in functional classes I to III (p less than 0.05). For valve replacement, the mortality rate was 12% (10 of 81 patients) and for declotting of the prosthesis 13% (3 of 23 patients).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Cardiothoracic Surgery, Johannesburg Hospital, Republic of South Africa.
authors.forename: E
authors.initials: E
authors.lastname: Deviri
authors.forename: P
authors.initials: P
authors.lastname: Sareli
authors.forename: T
authors.initials: T
authors.lastname: Wisenbaugh
authors.forename: S L
authors.initials: SL
authors.lastname: Cronje
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve; D006348:Cardiac Surgical Procedures / Q000401:mortality; D002648:Child; D002675:Child, Preschool; D005260:Female; D006331:Heart Diseases / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve; D011475:Prosthesis Failure; D015996:Survival Rate; D013927:Thrombosis / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery