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Thrombolysis is superior to heparin for non-obstructive mitral mechanical valve thrombosis . BACKGROUND AND AIM OF THE STUDY Non-obstructive prosthetic valve thrombosis ( PVT ) is a unique subset that features clinical presentation without heart failure , and may be asymptomatic . Thrombolysis has been accepted for obstructive PVT , but treatment strategies of non-obstructive PVT are controversial . This study compared the efficacy and safety of thrombolysis and heparin treatment in these patients . METHODS Between 1993 and 1998 , 20 consecutive patients were found by multiplane transesophageal echocardiography ( TEE ) to have non-obstructive PVT . TEE was performed for peripheral embolism in two patients , stroke or transient ischemic attack in six , stroke and fever in two , fever in one patient , as a routine postoperative examination in two patients , and for other reasons in seven . Patients were allocated to two groups : group I ( n = 8 ) received streptokinase-mediated fibrinolysis ; group II ( n = 12 ) received intravenous heparin by infusion . Treatment was monitored using TEE . RESULTS There was no difference between patient groups with regard to sex , age , type of prosthesis and time since operation , though anticoagulant status was more often inadequate in group II . By TEE , valve motion was normal in all patients . In group I , all thrombi were mobile and 5-13 mm in diameter ; in group II , all thrombi but three were mobile and 3-18 mm in diameter . In group I , thrombolysis was successful in all patients , without complications , within 6-72 h. In group II , heparin treatment was successful in six patients in 3-32 days . In one patient , seven days ' of unsuccessful heparin was followed by two months ' successful coumarin therapy . Among five unsuccessful cases , the thrombus size increased in four ( three became obstructive in 7-35 days ) ; all four patients were switched to fibrinolysis , which was successful without complications in 12-60 h. The fifth patient developed a stroke after nine days of heparin treatment and was subsequently operated on . CONCLUSIONS Non-obstructive PVT may be asymptomatic in one-third of patients . Thrombolysis is an efficient and safe treatment , and may be first-line therapy if there is no contraindication . Heparin treatment was successful in about one-half of our cases in the presence of sessile or small thrombi and inadequate anticoagulant status . In unsuccessful cases , thrombi became obstructive or caused stroke during heparin therapy , the adequate duration of which remains unclear .
799
Intervention_Physical
transesophageal echocardiography
800
Intervention_Pharmacological
streptokinase-mediated fibrinolysis ;
801
Intervention_Pharmacological
intravenous heparin by infusion .
802
Intervention_Pharmacological
heparin
803
Intervention_Pharmacological
Heparin
804
Outcome_Other
efficacy and safety
805
Outcome_Physical
valve motion
806
Outcome_Physical
thrombi
807
Outcome_Adverse-effects
complications
808
Outcome_Physical
thrombus size
809
Outcome_Adverse-effects
stroke
810
Outcome_Other
efficient and safe
811
Outcome_Adverse-effects
stroke
812
Participant_Condition
prosthetic valve thrombosis ( PVT )
813
Participant_Sample-size
20
814
Participant_Condition
non-obstructive PVT .