The Use of Novel Oral Anti-Coagulant’s (NOAC) compared to Vitamin K Antagonists (Warfarin) in patients with Left Ventricular thrombus after Acute Myocardial Infarction (AMI)

Abstract

Aim

Current guidelines recommend the use of Vitamin K Antagonist (VKA) for up to 3 – 6 months for treatment of LV thrombus post-acute myocardial infarction (AMI). However, based on evidence supporting non-inferiority of Novel Oral Anti-Coagulant’s (NOAC) compared to VKA for other indications such as DVT, PE and thrombo-embolic prevention in atrial fibrillation, NOACs are being increasingly used off licence for the treatment of LV thrombus post AMI. In this study we investigated the safety and effect of NOACs compared to VKA on LV thrombus resolution in patients presenting with AMI.

Methods and Results

This was an observational study of 2,328 consecutive patients undergoing Coronary Angiography +/- Percutaneous Coronary Intervention (PCI) for AMI between May 2015- December 2018, at a UK cardiac centre. Patients’ details were collected from the hospital electronic database. The primary end-point was rate of LV thrombus resolution with bleeding rates a secondary outcome.

Left ventricular (LV) thrombus was diagnosed in 101 (4.3%) patients. Sixty patients (59.4%) were started on VKA and 41 patients (40.6%) on NOAC therapy (rivaroxaban: 58.5%, apixaban, 36.5% and edoxaban: 5.0%). Both groups were well matched in terms of baseline characteristics including age, previous cardiac history (Previous MI, PCI, CABG), and cardiovascular risk factors (Hypertension, Diabetes, Hypercholesterolaemia).

Over the follow up period (median 2.2 years), overall rates of LV thrombus resolution were 86.1%. There was greater and earlier LV thrombus resolution in the NOAC group compared to patients treated with warfarin (82% vs 64.4%, p = 0.0018, at 1 year), which persisted after adjusting for baseline variables (OR 1.8 95% CI 1.2-2.9). Major bleeding events during the f/u period were lower in the NOAC group, compared with VKA group (0% vs 6.7%, p = 0.030) with no difference in rates of systemic thromboembolism (5% vs 2.4%, p = 0.388).

Conclusion

This data suggests improved thrombus resolution in post ACS LV thrombosis in patients treated with NOACs compared to vitamin K antagonists. This improvement in thrombus resolution was accompanied with a better safety profile for NOAC patients’ vs VKA treated patients. Thus, provides data to support a randomised trial to answer this question.