紅斑性狼瘡（systemic lupus erythematosus, SLE）會造成身體多種器官的傷害，心臟血管系統也是其主要目標器官之一。在紅斑性狼瘡病人之屍體解剖研究中，估計有超過一半以上的病人會有心臟血管的病變。此外， 紅斑性狼瘡會造成血栓，且常與抗磷酸脂抗體（antiphospholipid antibody）之存在有很大的關係。其所造成的血栓大多發生在動脈或靜脈血管，發生在心臟腔室中的血栓（intracardiac thrombus）卻很少見。本篇報告一位49歲紅斑性狼瘡女性病患，診斷13年後併發左心室血栓，病患之anticardiolipin IgG呈陽性，經投予類固醇及Warfarin抗凝血劑後，病情好轉，左心室血栓消失且無周邊血管或其他器官栓塞事件。 希望藉此病例及歷年文獻之回顧，探討紅斑性狼瘡引發血栓之可能成因及治療，讓基層醫師在照顧紅斑性狼瘡病人時，能有所參考。 (台灣家醫誌2004; 14: 104-11) Systemic lupus erythematosus (SLE) can cause multi-organ damages in which the cardiovascular system is one of the major targets. It is estimated that over half of the autopsies of SLE patients demonstrated cardiovascular pathologies. Furthermore, SLE can induce vascular thrombosis which is often related to the presence of antiphospholipid antibodies. The thrombus formed in SLE often occurs in arteries or veins, but seldom in the cardiac chambers (intracardiac thrombus). This case report demonstrates a 49-year-old female patient who, being diagnosed with SLE 13 years ago, presents with left ventricular thrombus formation. Her serum IgG-anticardiolipin antibody was positive. After treatment with corticosteroid and warfarin, her condition improved and the left ventricular thrombus disappeared. No other vascular or organic thromboembolic event was found. In this case presentation and literature review, we try to explore the possible causes and treatment of thrombosis related to SLE, and to provide a reference for primary care doctors providing care to SLE patients.