목 적： 인공판막 혈전증은 드물지만, 심각한 합병증을 초래한다. 최근에 혈전용해요법이 인공판막 혈전증에 있어서 수술적 요법의 대안으로 제시되어져 왔고, 그 사용이 증가 되어지고 있다. 하지만, 인공판막 혈전증의 치료지침은 아직 명확하게 정의되어지지는 않은 것 같으며, 감별진단 역시 어렵다. 방 법： 1998년 12월부터 2000년 2월까지 증상을 보인 네명의 환자에게서 일곱 차례 인공판막 혈전증으로 진단하고 아홉 차례의 혈전용해요법을 시행하였다. 심초음파 검사와 투시영상 촬영을 혈전용해요법 전후로 시행하였으며, 혈전용해제로는 urokinase와 rt-PA를 사용하였으며, 필요시 urokinase와 rt-PA를 한 차례 더 사용하였으며, 재발된 혈전증에도 혈전용해요법을 일차적으로 사용하였다. 결 과： 네 명의 환자 모두 여자였으며, 평균 연령은 38.5세 였다. 승모판 치환술과 삼첨판 치환술을 한 경우가 각각 두 명씩 이었다. 항응고제 사용상태는 대부분 부적절하였다(평균 INR：2.23). 첫 번째 혈전용해요법을 시행한 후의 성공률은 43%(3/7)이었으며, 추가로 혈전용해요법을 시행한 후의 총성공률은 54%(4/7)였다. 치료에 실패한 세 번의 경우는 수술이 필요하였다. 그 중 한 차례는 수술결과 혈전증에 의한 판막이상이 아닌, 판누스의 내성장에 의한 판막이상으로 밝혀졌다. 혈전용해요법에 따른 합병증은 없었다. 결 론： 혈전용해요법은 인공판막 혈전증에 있어서 수술적 방법의 대안으로 사용되어 질 수 있으며, 낮은 합병증을 보인다. 하지만 반복해서 재발하는 혈전증에 대한 치료지침과 적절한 항응고제 사용에 대하여 교육이 필요하리라 생각된다.

Background：Prosthetic valve thrombosis is an uncommon but serious complication. Thrombolytic therapy has recently been proposed as an alternative to surgical methods in treating this condition and is used increasingly. However, the indications for thrombolytic treatment in prosthetic valve thrombosis have not been well defined and differential diagnosis of thrombosis is still difficult. Methods：Four symptomatic patients with prosthetic valve thrombosis underwent 9 thrombolytic sessions for 7 distinct episodes. Transthoracic or transesophageal echocardiography and cinefluoroscopy were performed and repeated after each thrombolytic session. Urokinase or rt-PA (recombinant tissue-type plasminogen activator) was used and repeated dose was given if necessary. Recurrent thrombosis was treated also either with urokinase or rt-PA. Results：All patients were female and mean age was 38.5 years old. Two valves were in mitral position and the other two were in tricuspid position. The anticoagulation status was inadequate in three patients. The initial success after first dose was 43% (3/7), which increased to 54% (4/7) after repeated thrombolytic therapy. Thrombolytic therapy was failed in three episodes；two thromboses and one ingrowths of pannus. Operations were needed in these cases. No complication was seen. Conclusion：Thrombolytic treatment can be used as an alternative to surgical therapy with a low risk of complications. But guideline of thrombolytic therapy for the recurrent thrombosis and education for the patients about the adequate anticoagulation were needed.

Background：Prosthetic valve thrombosis is an uncommon but serious complication. Thrombolytic therapy has recently been proposed as an alternative to surgical methods in treating this condition and is used increasingly. However, the indications for thrombolytic treatment in prosthetic valve thrombosis have not been well defined and differential diagnosis of thrombosis is still difficult. Methods：Four symptomatic patients with prosthetic valve thrombosis underwent 9 thrombolytic sessions for 7 distinct episodes. Transthoracic or transesophageal echocardiography and cinefluoroscopy were performed and repeated after each thrombolytic session. Urokinase or rt-PA (recombinant tissue-type plasminogen activator) was used and repeated dose was given if necessary. Recurrent thrombosis was treated also either with urokinase or rt-PA. Results：All patients were female and mean age was 38.5 years old. Two valves were in mitral position and the other two were in tricuspid position. The anticoagulation status was inadequate in three patients. The initial success after first dose was 43% (3/7), which increased to 54% (4/7) after repeated thrombolytic therapy. Thrombolytic therapy was failed in three episodes；two thromboses and one ingrowths of pannus. Operations were needed in these cases. No complication was seen. Conclusion：Thrombolytic treatment can be used as an alternative to surgical therapy with a low risk of complications. But guideline of thrombolytic therapy for the recurrent thrombosis and education for the patients about the adequate anticoagulation were needed.

Prosthetic valve thrombosis·Thrombolytic treatment.