Caplacizumab for treating subacute intra-stent thrombus occurring despite efficacious double anti-platelet treatment and anticoagulation: a case report

Background Acute and subacute stent thromboses are a rare complication associated with high mortality and morbidity occurring in similar to 1.5% of patients treated with primary percutaneous intervention for ST-elevation myocardial infarction (STEMI). Recent publications describe a potential role of the von Willebrand factor (VWF) in thrombus formation at sites of critical coronary stenosis in STEMI. Case summary We describe a 58-year-old woman with STEMI at initial presentation, who suffered subacute stent thrombosis despite good stent expansion, efficacious dual antiplatelet therapy, and therapeutic anticoagulation. Because of very high VWF values, we administered N-acetylcysteine in order to depolymerize VWF, but the drug was not well tolerated. Since the patient was still symptomatic, we used caplacizumab in order to prevent VWF from interacting with platelets. Under this treatment, the clinical and angiographic course was favourable. Discussion Considering a modern view of intracoronary thrombus pathophysiology, we describe an innovative treatment approach, which eventually ended in a favourable outcome.

Automated summary

This article describes a rare complication of acute and subacute stent thrombosis, occurring in approximately 1.5% of patients treated with primary percutaneous intervention for ST-elevation myocardial infarction (STEMI). We present a case of a 58-year-old woman who experienced subacute stent thrombosis despite good stent expansion, dual antiplatelet therapy, and anticoagulation. Due to high von Willebrand factor (VWF) levels, N-acetylcysteine was administered to depolymerize VWF, but was not well tolerated. Caplacizumab was then used to prevent VWF from interacting with platelets, resulting in a favorable clinical and angiographic outcome.