title: Anticoagulation protocol and early prosthetic valve thrombosis.
abstract: BACKGROUND
  [corrected] Prosthetic valve thrombosis is a major cause of morbidity and mortality following heart valve replacement with a mechanical valve.
  
  
  RESULTS
  538 patients who underwent mechanical valve replacement between April 1999 and June 2003 were included in the study. They were divided into two groups. Group A (n=245) consisted of patients who underwent mechanical valve replacement between April 1999 and June 2001. Anticoagulation was started on the first post-operative day and consisted of only oral nicoumalone. Group B (n=293) consisted of patients who underwent mechanical valve replacement between July 2001 and June 2003; enoxaparin was started six hours following surgery in addition to oral nicoumalone which was started on first post-operative day. Fifteen (6.1%) patients in group A developed early prosthetic valve thrombosis at an interval of 4.33+/-0.97 months (range 3-6 months) following surgery. Ten had prosthetic valve thrombosis in the mitral position and five had prosthetic valve thrombosis in the aortic position. In group B, six (2.1%) patients developed early prosthetic valve thrombosis at a median interval of 4.58+/-0.9 months (range 3.5-6 months) in the mitral position (p=0.01).
  
  
  CONCLUSIONS
  Addition of enoxaparin to the anticoagulation regime in the immediate post-operative period significantly reduces early prosthetic valve thrombosis.
authors.affiliation: Cardiothoracic Centre, All India Institute of Medical Sciences, New Delhi.
authors.forename: Sachin
authors.initials: S
authors.lastname: Talwar
authors.forename: Chandra Kanta
authors.initials: CK
authors.lastname: Kapoor
authors.forename: Devagourou
authors.initials: D
authors.lastname: Velayoudam
authors.forename: Arkalgud Sampath
authors.initials: AS
authors.lastname: Kumar
mesh_terms: D000293:Adolescent; D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage* / Q000627:therapeutic use; D017984:Enoxaparin / Q000008:administration & dosage* / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D018447:Medical Futility; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology / Q000517:prevention & control; D013927:Thrombosis / Q000209:etiology / Q000517:prevention & control*; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants; D017984:Enoxaparin