title: Acute mechanical prosthetic valve thrombosis after initiating oral anticoagulation therapy. Is bridging anticoagulation with heparin required?
abstract: Prosthetic valve thrombosis (PVT) represents a serious and potentially lethal complication. It can be attributed more frequently to inadequate anticoagulant therapy. We present a case of acute aortic mechanical valve thrombosis six months after implantation. The patient discontinued oral anticoagulation after being discharged following the primary operation. Two days after reinitiating warfarin as an outpatient, he developed acute valve thrombosis presenting with symptoms and signs of cardiac failure. He was managed with intravenous thrombolysis with a recombinant plasminogen activator which resulted in immediate resolution of thrombus and clinical improvement. A paradox procoagulant effect of warfarin is evident on the first one or two days after initiation of therapy. A 'bridging' protocol with unfractionated or low molecular weight heparin (LMWH) should be considered, according to recently published guidelines, until warfarin reaches therapeutic levels and exerts an antithrombotic effect.
authors: Department of Thoracic and Cardiovascular Surgery, AHEPA University Hospital, Thessaloniki, Greece.
authors: Nicholas
authors: N
authors: Charokopos
authors: Polychronis
authors: P
authors: Antonitsis
authors: Panagiotis
authors: P
authors: Artemiou
authors: Efthymia
authors: E
authors: Rouska
authors: Christophoros
authors: C
authors: Foroulis
authors: Christos
authors: C
authors: Papakonstantinou
mesh_terms: D000074:Acenocoumarol / Q000008:administration & dosage* / Q000009:adverse effects; D000208:Acute Disease; D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects; D001022:Aortic Valve Insufficiency / Q000209:etiology / Q000601:surgery*; D004696:Endocarditis / Q000150:complications; D005343:Fibrinolytic Agents / Q000008:administration & dosage; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation; D006493:Heparin / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D008297:Male; D055118:Medication Adherence; D000077785:Tenecteplase; D015912:Thrombolytic Therapy; D013927:Thrombosis / Q000188:drug therapy / Q000209:etiology* / Q000517:prevention & control; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage; D016896:Treatment Outcome; D014859:Warfarin / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D000925:Anticoagulants; D005343:Fibrinolytic Agents; D014859:Warfarin; D006493:Heparin; D010959:Tissue Plasminogen Activator; D000074:Acenocoumarol; D000077785:Tenecteplase