Aspirin Nonresponsiveness in Congenital Heart Disease-Prevalence, Risk Factors, and Management

Area of Science:

• Cardiology
• Pediatrics
• Pharmacology

Background:

• Aspirin is a common antiplatelet therapy for congenital heart disease (CHD).
• Aspirin nonresponsiveness, measured by aspirin reaction units (ARU), increases thrombotic event risk.
• Optimal aspirin dosing strategies for nonresponsive pediatric CHD patients are unclear.

Purpose of the Study:

• To determine the prevalence of aspirin nonresponsiveness in pediatric CHD patients.
• To identify risk factors associated with aspirin nonresponsiveness.
• To evaluate the efficacy of aspirin dose escalation in achieving therapeutic responsiveness.

Main Methods:

• Retrospective review of 142 pediatric patients with CHD treated with aspirin.
• Evaluation of aspirin responsiveness using aspirin reaction units (ARU).
• Analysis of demographic and clinical data, including dose adjustments and thrombotic events.

Main Results:

• 22.5% of patients were initially nonresponsive to aspirin.
• 83% of nonresponsive patients achieved therapeutic ARU levels after dose or duration adjustments.
• Increased aspirin dosage was effective in 63% of patients who became responsive.
• 12% of patients experienced thrombotic events, with most occurring despite initial therapeutic ARU levels.

Conclusions:

• Aspirin nonresponsiveness is prevalent in pediatric CHD patients on initial weight-based dosing.
• Aspirin dose escalation can effectively restore therapeutic responsiveness in many nonresponsive patients.
• Regular monitoring of ARUs is crucial to ensure adequate aspirin antiplatelet effect in pediatric CHD.