Association of α_(2A)-Adrenergic Receptor Genetic Variants with Platelet Reactivity in Chinese Patients on Dual Antiplatelet Therapy Undergoing Percutaneous Coronary Intervention

Objective The alpha 2A-adrenergic receptor gene （ADRA2A） polymorphism in individuals antiplatelet response to sympathetic stimulation. The aim of this study was to investigate ADRA2A variants on platelet reactivity in Chinese patients on dual antiplatelet therapy undergoing percutaneous coronary intervention （PCI）. modifies the the effect of （DAPT） after Methods From March 2011 to March 2013, 1,024 patients were enrolled in this prospective, single-center, observational study in China. Four single nucleotide polymorphisms （SNPs） of ADRA2A gene （rs11195419, rs3750625, rs13306146, and rs553668） and CYP2C19^＊2 were detected by ligase detection reaction （LDR）, and adenosine diphosphate （ADP） inhibition was detected by thromboelastography （TEG）. Results The minor allele frequencies of ADRA2A SNPs were common. Platelet ADP inhibition was significantly different among patients carrying rs11195419 （adjusted P = 0.022） and rs3750625 （adjusted P = 0.016）. The homozygous allele carriers had the lowest ADP inhibition. However, ADP inhibition was not significantly different in rs553668 and rs13306146. At the multivariate analysis, rs11195419 （P = 0.033）, rs3750625 （P = 0.020） and CYP2C19＂2 （P = 0.002） were independent predictors of ADP inhibition. Subgroups analysis based on sex showed rs11195419 （P = 0.003） and rs3750625 （P = 0.002） were significantly associated with ADP inhibition in males, but not in females. Conclusion ADRA2A genetic variations were associated with ADP-induced platelet aggregation during DAPT in Chinese patients undergoing PCI, and the effect was particularly more pronounced in males.

Efficacy of Intra-aortic Balloon Pump before versus after Primary Percutaneous Coronary Intervention in Patients with Cardiogenic Shock from ST-elevation Myocardial Infarction

Background： Previous studies showed that patients with cardiogenic shock （CS） from ST-elevation acute myocardial infarction （STEMI） supported by intra-aortic balloon pump （IABP） before primary percutaneous coronary intervention （PCI） decreased the risk of in-hospital mortality than patients who received IABP after PCI. However, little evidence is available on the optimal order of IABP insertion and primary PCI. The aim of this study was to investigate the impact of the sequence of IABP support and PC1 and its association with major adverse cardiac and cerebrovascular events （MACCEs）. Methods： Data were obtained from 218 consecutive patients with CS due to STEMI in Beijing Anzhen Hospital between 2008 and 2014% who were treated with 1ABP and PCI. The patients were divided into two groups： Group A in whom IABP received before PCI （n = 106） and Group B in whom IABP received after PCI （n = 112）. We evaluated the myocardial perfusion using myocardial blush grade and resolution of ST-segment elevation. The primary endpoint was 12-month risk of MACCE. Results： Most baseline characteristics were similar in patients between the two groups. However, patients received 1ABP before PCI were associated with a delay of door-to-balloon time （DBT） and higher troponin I level （P 〈 0.05）. However, myocardial perfusion was significantly improved in patients treated with IABP before PCI （P 〈 0.05）. Overall, IABP support before PCI was not associated with significantly lower risk of MACCE （P 〉 0.05）. In addition, risk of all-cause mortality, bleeding, and acute kidney injury （AKI） was similar between two groups （P 〉 0.05）. Multivariate analysis showed that DBT （odds ratio [OR] 2.5, 95% confidence interval [C/] 1.1-4.8, P=0.04）, lABP support after PCI （OR 5.7, 95% Cl 2.7-8.4, p〈0.01）, and AKI （OR 7.4, 95% CI 4.9 10.8, P- 0.01） were the independent predictors of mortality at 12-month follow-up. Conclusions： Early IABP insertion before primary PCI is associated with improved myocardial perfusion although DBT increases. IABP support before PCI does not confer a 12-month clinical benefit when used for STEMI with CS.