Is Aspirin (acetylsalicylic acid) indicated for patients undergoing aortic valve replacement?

From the Guidelines

Aspirin is recommended after aortic valve replacement, specifically for bioprosthetic valves, at a dose of 75-100 mg daily for at least 3-6 months after surgery, and may be continued indefinitely based on individual risk factors. The use of aspirin in this context is supported by the 2021 guideline for the prevention of stroke in patients with stroke and transient ischemic attack, which suggests that long-term therapy with only aspirin 75 to 100 mg daily is recommended after 3 to 6 months after bioprosthetic valve surgery 1. This recommendation is based on the results of observational studies that have reported an increased risk of ischemic stroke early after surgery.

For patients with bioprosthetic aortic valves, the addition of aspirin to anticoagulant therapy may decrease the postoperative thromboembolic risk, but it also increases the bleeding risk, and therefore, cannot be recommended routinely 1. However, the 2020 ACC/AHA guideline for the management of patients with valvular heart disease suggests that aspirin may be used in conjunction with warfarin for the first 3 months after surgery, during which time the valve surface is becoming endothelialized 1.

The decision to use aspirin after aortic valve replacement should be individualized, taking into account the patient's risk factors for thromboembolism and bleeding. Patients should be monitored regularly by their cardiac surgeon or cardiologist to adjust anticoagulation therapy as needed. Key considerations include:

• The type of valve used (bioprosthetic or mechanical)
• The patient's risk factors for thromboembolism and bleeding
• The need for anticoagulation therapy after surgery
• The potential benefits and risks of aspirin therapy in this context

In terms of specific dosing, aspirin 75-100 mg daily is a commonly recommended dose for patients with bioprosthetic aortic valves, and it should be taken with food to minimize gastrointestinal side effects. Patients should also be informed about the potential risks of bleeding and bruising, and should report any unusual symptoms to their healthcare providers. Overall, the use of aspirin after aortic valve replacement is an important aspect of thromboembolic prevention, and should be tailored to the individual patient's needs and risk factors.

From the Research

Aspirin for Aortic Valve Replacement

• The use of aspirin after aortic valve replacement, particularly transcatheter aortic valve replacement (TAVR), has been studied in several research papers 2, 3, 4.
• Current practice guidelines recommend dual antiplatelet therapy (DAPT) following TAVR using a combination of low-dose aspirin and clopidogrel for 3-6 months 2.
• However, recent studies have suggested that aspirin alone may be sufficient and could decrease the risk of bleeding without increasing the risk of mortality, stroke, or myocardial infarction compared to DAPT 3, 4.
• A systematic review and meta-analysis found that aspirin alone was not associated with a statistically significant difference in the rate of bleeding events, all-cause mortality, stroke, and myocardial infarction compared to DAPT at 30 days follow-up 3.
• Another study found that aspirin alone significantly reduced the composite of thromboembolic and bleeding events compared to DAPT in patients without an indication for oral anticoagulation undergoing TAVR 4.

Antithrombotic Therapy

• The optimal antithrombotic regimen and duration of therapy following TAVR are still being studied and debated 2, 3, 4.
• The decision to use aspirin alone or DAPT should be made on a patient-specific basis, taking into account the individual's risk of bleeding and thromboembolic events 3, 4.
• Patients with established cardiovascular disease but without a coronary stent may likely continue aspirin during the perioperative period unless undergoing closed-space surgery 5.

Aortic Stenosis and Coronary Artery Disease

• Aortic stenosis and coronary artery disease frequently coexist and share pathophysiological mechanisms 6.
• The management of patients with aortic stenosis and coronary artery disease requiring revascularization has expanded with the advent of TAVR, and the decision between surgical and transcatheter management should be made on a patient-specific basis 6.