Use of Anticoagulant Therapy in Patients with Acute Myocardial Infarction and Atrial Fibrillation

Abstract

The incidence of atrial fibrillation (AF) in acute coronary syndrome (ACS) ranges from 2.3-23%. This difference in the incidence of AF is explained by the different ages of the patients in different studies and the different times of application of both reperfusion and drug therapies in acute myocardial infarction (AMI). About 6-8% of patients who underwent percutaneous intervention within AMI have an indication for oral anticoagulant therapy with vitamin K antagonists or new oral anticoagulants (NOAC).The use of oral anticoagulant therapy should be consistent with individual risk of bleeding as well as ischemic risk. Both HAS-BLED and CHA2DS2VASc scores are most commonly used for risk assessment. Except in patients with mechanical valves and antiphospholipid syndrome, NOACs have an advantage over vitamin K antagonists (VKAs). One of the advantages of NOACs is the use of fixed doses, where there is no need for successive INR controls, which increases the patient's compliance in taking these drugs. The use of triple therapy in ACS is indicated in the case of patients with AF, mechanical valves as well as venous thromboembolism. The results of the studies showed that when choosing a P2Y12 receptor blocker, less potent P2Y12 blockers such as Clopidogrel should be chosen, due to the lower risk of bleeding. It has been proven that the presence of AF within AMI is associated with a higher degree of reinfarction, more frequent stroke, high incidence of heart failure, and there is a correlation with an increased risk of sudden cardiac death. With the appearance of AF in ACS, its rapid conversion into sinus rhythm is necessary, and in the last resort, good control of heart rate in order to avoid the occurrence of adverse clinical events.

Keywords: acute myocardial infarction; anticoagulant therapy; atrial fibrillation.

Figure 1

Cardiovascular risk factors for the development of AF [1]: Legend: AF—atrial fibrillation; CAD—coronary artery disease; COPD—chronic obstructive pulmonary disease; LA—left antrum; OSA—obstructive sleep apnea; HF—heart failure; VHD—valvular heart disease; CRF—chronic renal failure.

Figure 2

Use of OAC therapy in patients with AF after an ACS [57]. Legend: * Aspirin dose 75–150 mg daily; ** Clopidogrel dose 75 mg daily; ACS—acute coronary syndrome; AF—atrial fibrillation; OAC—oral anticoagulation (using vitamin K antagonist or non-vitamin K antagonist oral anticoagulants).