aspirin resistance in children with congenital heart disease and its relationship with laboratory and clinical parameters

Background: patients with congenital heart disease (chd) are more prone to thromboembolism. aspirin is the most commonly used medication around the world to prevent thrombosis in cardiovascular diseases. objectives: this study aimed to define the frequency of aspirin resistance in pediatric patients with chd and to evaluate the correlation of clinical and laboratory parameters with aspirin resistance. methods: the study population consisted of 103 patients using aspirin, including 53 cases of cyanotic chd and 50 cases of noncyanotic chd. platelet aggregation was measured by the aggreguide a-100 adp assay. results: the prevalence of aspirin resistance was 36.9% in children with chd. although aspirin resistance in cyanotic chd patients (41.5%) was higher than in non-cyanotic patients (32%), the difference was not statistically significant (p = 0.414). there was no significant association between aspirin responsiveness or resistance and the patient’s sex, age, duration of aspirin use, and concomitant medication use. comparison of the laboratory data of aspirin-responsive and -resistant patients showed no significant difference between these groups, except for albumin (p = 0.032) and serum fibrinogen (p = 0.0001) levels. the fibrinogen level and thromboembolism history were independent risk factors for aspirin resistance. also, there was a significant correlation between platelet aggregation in peripheral blood smears and aspirin resistance (p = 0.0001). conclusions: our findings suggest that measurement of the serum fibrinogen level and platelet aggregation in blood smears may be the first step to predict aspirin resistance.