Ticagrelor versus Clopidogrel in the Dual Antiplatelet Regimen for Unruptured Intracranial Aneurysm Treated with Stent-Assisted Coil Embolization: A Single-Center Cohort Study

BACKGROUND

Dual antiplatelet therapy (DAPT) of aspirin plus clopidogrel is commonly used in patients with unruptured intracranial aneurysms treated with stent-assisted coil (SAC) embolization. However, the unpredictable clopidogrel efficacy of the 5%-55% nonresponders limits its use. Ticagrelor, as a potential alternative of clopidogrel, is an antiplatelet agent with low resistance rates but uncertain efficacy and safety in these patients.

METHODS

A single-center cohort study was performed to compare the efficacy and safety of ticagrelor with clopidogrel in the DAPT regimen in patients with unruptured intracranial aneurysms and treated with SAC. The patients with clopidogrel resistance identified as inadequate adenosine diphosphate inhibition rate determined by thromboelastography were treated with ticagrelor instead, and both drugs achieved adequate suppression of platelet aggregation when stents were implanted. The occurrence of major adverse cardiovascular and cerebrovascular events (MACCE) and bleeding events was recorded through 6 months follow-up.

RESULTS

Data from 86 patients with 99 unruptured intracranial aneurysms and treated by SAC with clopidogrel were compared with those from 108 patients with 111 aneurysms and treated with ticagrelor. Neither the baseline characteristics nor the incidence of the MACCE or bleeding events differed between the groups. Ticagrelor exerted significantly higher adenosine diphosphate inhibition rate than that of the clopidogrel. Multivariable logistic regression analysis showed that the incidence of MACCE was related to hematocrit and fibrinogen levels.

CONCLUSIONS

Ticagrelor seemed to be as effective and safe as clopidogrel for SAC in unruptured intracranial aneurysms. Hematocrit and fibrinogen levels were independent risk factors for the incidence of MACCE.

Variability of daily creatinine excretion in healthy adults

In order to determine the within-subject variability of creatinine excretion, the 24-h output was measured over 5 consecutive d in 12 subjects. The mean within-subject coefficient of variation was 3.6 per cent. There was much greater variation between subjects. The creatinine excretion in g/d was 30-40 per cent lower in Burmese subjects than in Europeans and North Americans, but the excretion per kg was slightly higher, suggesting that the Burmese are more muscular.

BCG test reaction in previously BCG vaccinated children

BCG test reactions were studied in 1095 non-tuberculous children from 6 months to 5 years of age, who had received BCG vaccination in the newborn period, in order to find out the diagnostic value of the BCG test in previously BCG vaccinated children. Previous BCG vaccination has an effect on the BCG test reaction in the form of an accelerated BCG reaction. Although the degree of reaction decreases with time, 51.4% of children still showed a strongly accelerated BCG reaction 4 1/2-5 years after BCG vaccination. It is concluded that the BCG test cannot be used as a diagnostic test for tuberculosis in children under 5 years of age who have had previous BCG vaccination.

Diagnosis of right ventricular outflow obstruction in infants by cross sectional echocardiography

Cross sectional echocardiographic studies were assessed prospectively in 58 infants in whom right ventricular outflow obstruction was subsequently shown angiographically. A subcostal cut was used to display simultaneously the short axis of the aortic root and the long axis of the right ventricular outflow tract. This facilitated the differentiation of the common right ventricular outflow tract obstructive lesions. Tetralogy of Fallot was diagnosed correctly in 22 of 26 infants; pulmonary atresia with intact septum in all of 14 neonates; isolated severe pulmonary valve stenosis in all of nine infants; and pulmonary atresia with ventricular septal defect in eight of nine infants. The subcostal approach is the technique of choice for evaluating right ventricular outflow tract obstruction as it is more reliable than the left parasternal approach.