LV Thrombus After Acute AMI: A Randomized Controlled Trial

Left Ventricular Thrombus Formation After Acute Myocardial Infarction - a Randomized Multi-center Trial Comparing Two Different Anti-thrombotic Regimens

Left Ventricular (LV) thrombus formation is witnessed in at least 10% of patients with ST segment elevation myocardial infarction (STEMI). It is a feared complication since it might increase the risk of thrombo-embolic events, including stroke. Guidelines recommend vitamin K antagonist treatment in these patients. However patients with STEMI nowadays undergo primary percutaneous coronary intervention (PCI) with coronary stent placement and consequently require dual anti-platelet therapy (ascal and P2Y12 inhibitors) to prevent stent thrombosis. Consequently, STEMI patients with LV thrombus are currently treated with triple antithrombotic therapy (aspirin, P2Y12 inhibitors, e.g. clopidogrel (75 mg/d) and vitamin K antagonist). Patients treated with triple antithrombotic therapy are subject to a strongly increased bleeding risk with a yearly incidence of 3.7% for dual anti-platelet therapy as compared to 12% for triple antithrombotic therapy. About 10% of these bleedings are cerebral. The mortality of such haemorrhagic strokes is 25%. A recent retrospective analysis did not show any beneficial effects of addition of vitamin K antagonist to dual anti-platelet therapy to prevent stroke. If vitamin K antagonist-therapy could be omitted, morbidity and mortality due to post-PCI bleedings will decrease. Therefore, a randomized trial is warranted to address this issue. Design: A multicenter, prospective, randomized, two non-inferiority trial. The objective of the study is to determine in a randomized fashion the risks and benefits of the addition of vitamin K antagonists to dual anti-platelet therapy or dual anti-platelet therapy in patients with PCI-treated STEMI and LV thrombus formation on baseline echocardiography or baseline Magnetic Resonance Imaging (MRI).

The proportions of patients with new cerebral micro-infarcts at 6 months relative to baseline measured by MRI.

Primary outcome is defined as the proportions of patients with new cerebral micro-infarcts at 6 months relative to baseline measured by Magnetic Resonance Imaging.

Inclusion Criteria: Suspected Left Ventricular thrombus on echocardiography or routine Magnetic Resonance Imaging Ongoing treatment with dual antiplatelet therapy according to ESC/ACC-AHA guidelines at the time of randomization. Exclusion Criteria: Younger than 18 Clinically or hemodynamically unstable Treatment with vitamin K antagonist prior to PCI or other expected indication for vitamin K antagonist treatment (e.g. atrium fibrillation) within the next 6 months Previous stroke or transient ischemic attack Scheduled for major surgery (including Coronary Artery Bypass Grafting) during the course of the study Active bleeding or high risk for bleeding contraindicating treatment with vitamin K antagonists Contra-indication for vitamin K antagonist treatment Chronic treatment with NSAIDs or COX-2 inhibitors for more than 4 days per week anticipated to continue during the study Congenital cardiac disease Presence of supraventricular or ventricular arrhythmias Expected candidate for ICD implantation with the next 6 months Severe renal impairment (estimated CrCl calculated by Cockcroft-Gault equation 5 30mL/min) Known or symptomatic brain disease (such as brain tumor) Women who are pregnant. Any contraindication for Contrast-Enhanced Magnetic Resonance Imaging (such as pacemaker, cerebrovascular clips, known contrast allergy, claustrophobia) Follow-up impossible (for example no fixed abode)