Platelet function monitoring guided antiplatelet therapy in patients receiving high-risk coronary interventions

Background Large-scale clinical trials have shown that routine monitoring of the platelet function in patients after percutanous coronary intervention （PCI） is not necessary. However, it is still unclear whether patients received high-risk PCI would benefit from a therapy which is guided by a selective platelet function monitoring. This explanatory study sought to assess the benefit of a therapy guided by platelet function monitoring for these patients. Methods Acute coronary syndrome （ACS） patients （n=384） who received high-risk, complex PCI were randomized into two groups. PCI in the two types of lesions described below was defined as high-risk, complex PCI： lesions that could result in severe clinical outcomes if stent thrombosis occurred or lesions at high risk for stent thrombosis. The patients in the conventionally treated group received standard dual antiplatelet therapy. The patients in the platelet function monitoring guided group received an antiplated therapy guided by a modified thromboelastography （TEG） platelet mapping： If inhibition of platelet aggregation （IPA） induced by arachidonic acid （AA） was less than 50% the aspirin dosage was raised to 200 mg/d; if IPA induced by adenosine diphosphate （ADP） was less than 30% the clopidogrel dosage was raised to 150 mg/d, for three months. The primary efficacy endpoint was a composite of myocardial infarction, emergency target vessel revascularization （eTVR）, stent thrombosis, and death in six months. Results This study included 384 patients; 191 and 193 in the conventionally treated group and platelet function monitoring guided group, respectively. No significant differences were observed in the baseline clinical characteristics and interventional data between the two groups. In the platelet function monitoring guided group, the mean IPA induced by AA and ADP were （69.2＋24.5）% （range, 4.8% to 100.0%） and （51.4＋29.8）% （range, 0.2% to 100.0%）, respectively. The AA- induced IPA of forty-three （22.2%） patients was less than 50% and the ADP-induced IPA of fifty-seven （29.5%） patients was less than 30%; therefore, their drug dosages were adjusted. The TEG was rechecked one to four weeks after PCI, and the results indicated that the IPAs had significantly improved （P 〈0.01）. However, no significant differences were found in the rates of the primary efficacy endpoint. Rates in the conventionally treated group and platelet function monitoring guided group were 4.7% and 5.2%, respectively （hazard ratio： 1.13; P=0.79）. Conclusion An antiplatelet therapy guided by TEG monitored platelet function could not improve clinical efficacy even in ACS patients treated with high-risk complex PCI.

Comparison of Long-term Outcomes in Patients with Premature Triple-vessel Coronary Disease Undergoing Three Different Treatment Strategies： A Prospective Cohort Study

Background： Patients with premature triple-vessel disease （PTVD） have a higher risk of recurrent coronary events and repeat revascularization： however, the long-term outcome of coronary artery bypass grafting （CABG）, percutaneous coronary intervention （PCI）, and medical therapy （MT） alone for PTVD patients is controversial. The aim of this study is to evaluate the long-term outcome of PTVD patients among these three treatment strategies, to find out the most appropriate treatment methods lbr these patients. Methods： One thousand seven hundred and ninety-two patients with PTVD （age： men 〈50 years and women _〈60 years） were enrolled between 2004 and 2011. The primary end point was all-cause death. The secondary end points were cardiac death, myocardial infarction, stroke, or repeat revascularization. Results： PCI, CABG, and MT alone were performed in 933 （52.1%）, 459 （25.6%）, and 400 （22.3%） patients. Both PCI and CABG were associated with lower all-cause death （4.6% vs. 4.1% vs. 15.5%, respectively, P 〈 0.01） and cardiac death （2.8% vs. 2.0% vs. 9.8%, respectively, P 〈 0.01 ） versus MT alone. The rate of repeat revascularization in the CABG group was significantly lower than those in the PCI and MT groups. After adjusting for baseline factors, PCI and CABG were still associated with similar lower risk of all-cause death and cardiac death versus MT alone （all-cause death： hazard ratio [HR]： 0.35, 95% confidence interval [CI]： 0.23-0.53, P 〈 0.01 and HR： 0.35, 95% CI： 0.18-0.70, P= 0.003, respectively, and cardiac death： HR： 0.32, 95% CI： 0.19-0.54, P〈 0.01 and HR： 0.36, 95% CI：0.14-0.93, P = 0.03, respectively）. Conclusions： PCI and CABG provided equal long-term benefits for all-cause death and cardiac death for PTVD patients. Patients undergoing MT alone had the worst long-term clinical outcomes.