In clinical practice, a dual therapy regimen combining Oral Anticoagulants (OAC) and aspirin is routinely used in patients with Chronic Coronary Syndrome (CCS) who have a history of coronary stenting. However, the results of a multicenter clinical trial cast doubt on this empirical practice. The goal of this study is to determine the optimal antithrombotic treatment regimen for a population at high risk (thromboembolic and hemorrhagic).
Chronic Coronary Syndrome (CCS) is a pathological condition characterized by the narrowing of the coronary arteries, which leads to a reduction in blood supply to the heart muscle. These patients are regularly prescribed oral anticoagulants for the prevention of thrombus-related stroke (especially in the case of atrial fibrillation) and antiplatelet agents (e.g., aspirin) to prevent thrombus formation in stents. This combination of drugs increases the risk of bleeding, while there is no solid evidence that such an approach increases the effectiveness of heart attack and stroke prevention.
Key Findings of the AQUATIC Study
The AQUATIC study, conducted in 51 centers in France, included 872 patients. These subjects, with a history of coronary stenting and high atherothrombotic risk, were randomly divided into two groups:
Oral anticoagulant in combination with aspirin (dual therapy).
Monotherapy with an oral anticoagulant.
The main objective of the study was to evaluate whether the addition of aspirin would lead to an improvement in patient outcomes (without additional harm) over an average follow-up period of 2.2 years.
Primary Clinical Outcome: Patients who received dual antithrombotic treatment (a combination of aspirin and an oral anticoagulant), compared to the monotherapy group, had a statistically significantly increased incidence of both major adverse cardiovascular events (MACE) (e.g., myocardial infarction, stroke, etc.) (16.9% vs. 12.1%) and All-Cause Mortality (13.4% vs. 8.4%).
Hemorrhagic Complications: The frequency of severe bleeding events in the combined therapy group almost tripled (10.2% vs. 3.4%, respectively). This calls into question the safety of this dual regimen.
Assessment of Efficacy: The addition of aspirin did not result in any additional benefit in terms of preventing atherothrombotic events (such as myocardial infarction or stent thrombosis).
Study Prematurely Terminated: Due to the significantly increased mortality in the dual therapy group.
Ultimately, the AQUATIC study supports the opinion that for subjects who have Chronic Coronary Syndrome and are receiving long-term oral anticoagulant therapy (including after stenting), discontinuing aspirin may be a safer choice without reducing the therapeutic effect.
Source: nejm
