title: Prolonged heparin and vitamin K antagonist regimen for early non-obstructive thrombosis of mechanical mitral valve prostheses.
abstract: OBJECTIVE
  Transesophageal echocardiography (TEE) has been used to document the incidence of non-obstructive thrombosis (NOT) after mechanical prosthetic mitral valve replacement (MVR). The postoperative occurrence and unpredictable evolution of NOT complicate its management. The study aim was to examine the safety and efficacy of prolonged, combined administration of heparin and vitamin K antagonists (VKA) recommended for this indication.
  
  
  METHODS
  All patients who underwent mechanical prosthetic MVR between July 1999 and December 2004 at the authors' institution were systematically studied with TEE immediately after surgery. Patients who presented with > or = 5 mm NOT were treated with combined heparin and VKA until TEE-confirmed resolution of the thrombus.
  
  
  RESULTS
  Among 256 patients who underwent 263 MVRs (seven reinterventions), 47 (17.9%) presenting with > or = 5 mm NOT received combined heparin and VKA for between 7 and 115 days (median 17 days). No thromboembolic or hemorrhagic events or deaths were observed during this period of observation. Four patients were treated with danaparoid and VKA because of thrombocytopenia induced by heparin before the diagnosis of NOT. Over a mean follow up of 39 months, one patient died from cancer and another from the sequelae of a stroke. In total, there were five NOT recurrences, three of which were complicated by embolic events without sequelae within eight months, and one by a recurrent stroke. In addition, three patients without demonstrable NOT recurrence suffered transient ischemic attacks.
  
  
  CONCLUSIONS
  Among this small sample of patients, combined heparin and VKA was well tolerated and effective, and could prevent reoperation or thrombolysis. These observations may warrant further study in a larger patient population.
authors.affiliation: Department of Cardiology and Vascular Diseases, CHU, Rennes, France. marcel.laurent@chu-rennes.fr
authors.forename: Marcel
authors.initials: M
authors.lastname: Laurent
authors.forename: Bernard
authors.initials: B
authors.lastname: Lelong
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Verhoye
authors.forename: Claire
authors.initials: C
authors.lastname: Khattar
authors.forename: Christian
authors.initials: C
authors.lastname: de Place
authors.forename: Pierre
authors.initials: P
authors.lastname: Matali
authors.forename: Celine
authors.initials: C
authors.lastname: Chabanne
authors.forename: Guillaume
authors.initials: G
authors.lastname: Leurent
authors.forename: Thierry
authors.initials: T
authors.lastname: Langanay
authors.forename: Alain
authors.initials: A
authors.lastname: Leguerrier
mesh_terms: D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects; D002423:Cause of Death; D004359:Drug Therapy, Combination; D017548:Echocardiography, Transesophageal; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000401:mortality / Q000601:surgery*; D006350:Heart Valve Prosthesis; D006470:Hemorrhage / Q000139:chemically induced / Q000401:mortality; D006493:Heparin / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D008134:Long-Term Care; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000401:mortality; D020521:Stroke / Q000139:chemically induced / Q000401:mortality; D013927:Thrombosis / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000401:mortality; D014812:Vitamin K / Q000037:antagonists & inhibitors*
chemical_list: D000925:Anticoagulants; D014812:Vitamin K; D006493:Heparin