AIM To explore the basic status and main influencing factors of the platelet aggregation rate by measuring the platelet aggregation rate before the first use of postoperative aspirin in children with congenital heart disease at high risk of thrombosis, so as to provide a preliminary basis for the accurate evaluation of aspirin effect.
METHODS A prospective cohort study was conducted in our Pediatric Cardiac Center. Congenital heart disease children at high risk of thromboembolism who were hospitalized for surgery from April 2020 to September 2020 were included in this study. An informed consent was signed and the arachidonic acid induced platelet aggregation rate (PAG-AA) was measured just before the first dose of aspirin after the operation. Thus, the basic status of PAG-AA values for this population were obtained. Through the single factor and multiple factors analysis, the influencing factors were investigated.
RESULTS A total of 196 patients met the inclusion criteria and signed informed consent (116 males; median age of 13 months, 13 days～6 years; and mean weight of 10.2 ± 4.9 kg). The median PAG-AA in basal state was 20.7% (1.3%-86.59%), with 67.3% distributed under 55% and 47.9% under 20%. Patients undergoing cardiopulmonary bypass had a significantly lower basic PAG-AA than those without cardiopulmonary bypass (31 ± 27 vs. 58 ± 28, P<0.05) and the basic PAG-AA values within 3 days after the cardiopulmonary bypass were significantly lower than those 3 days after cardiopulmonary bypass (26 ± 26 vs. 49 ± 26, P<0.01). Cyanosis patients had an obvious higher basic PAG-AA than patients without cyanosis (39 ± 27 vs. 26 ± 26, P<0.05). Multivariate regression analysis showed that cardiopulmonary bypass and the time point of testing after the operation were the main factors affecting the basic PAG-AA values in children with congenital heart disease, and cyanosis had no significant influence.
CONCLUSION The basic value of platelet aggregation rate after operation in children with congenital heart disease at high risk of thromboembolism fluctuates widely, with the majority below normal and nearly 50% of them in severely low state. The main influencing factors are cardiopulmonary bypass and the time point of testing. PAG-AA is significantly lower when the test is done within 3 days after the cardiopulmonary bypass and cyanosis has no significant impact on the baseline value. PAG-AA values 3 days after the cardiopulmonary bypass are recommended for accurate evaluation of the effect of aspirin.
DownLoad: