Natural course of left atrial thrombi after bioprosthetic mitral valve replacement in a patient with heparin-induced thrombocytopenia.

Left atrial (LA) clots involving prosthetic mitral valves are unusual complications of heparin-induced thrombocytopenia (HIT), and little is known about their natural history. A 73-year-old woman underwent bioprosthetic mitral valve replacement, which was complicated by atrial fibrillation and LA thrombus due to HIT. She was treated medically and followed up for 18 months. The present case provides unique insights into the natural history of HIT-related LA thrombus involving a bioprosthetic valve. It highlights the importance of having a high index of suspicion for this condition and avoiding the use of warfarin early in the course of the condition.