Smoking and outcomes following personalized antiplatelet therapy in chronic coronary syndrome patients: A substudy from the randomized PATH-PCI trial

BACKGROUND

This is a sub-analysis of the Personalized Antithrombotic Therapy for Coronary Heart Disease after PCI (PATH-PCI) trial in China to explore the relationship between smoking and outcomes following personalized antiplatelet therapy (PAT) in chronic coronary syndrome (CCS) patients undergoing percutaneous coronary intervention (PCI).

METHODS

As a single-center, prospective, randomized controlled and open-label trial, the PATH-PCI trial randomized CCS patients undergoing PCI into standard group or personalized group guided by a novel platelet function test (PFT), from December 2016 to February 2018. All patients were divided into smokers and nonsmokers according to their smoking status. Subsequently, we underwent a 180-day follow-up evaluation. The primary endpoint was the net adverse clinical events (NACE).

RESULTS

Regardless of smoking status, in the incidence of NACE, there was a reduction with PAT but that the reductions are not statistically significant. In the incidence of bleeding events, we found no statistically significant difference between two groups (smokers: 2.0% vs. 1.4%, HR = 1.455, 95% confidence interval [CI]: 0.595-3.559, p = .412; nonsmokers: 2.2% vs. 1.8%, HR = 1.228, 95% CI: 0.530-2.842, p = .632). In smokers, PAT reduced major adverse cardiac and cerebrovascular events (MACCE) by 48.7% (3.0% vs. 5.9%, HR = 0.513, 95% CI: 0.290-0.908, p = .022), compared with standard antiplatelet therapy (SAT). PAT also reduced the major adverse cardiovascular events (MACE) but there was no statistically difference in the reductions (p > .05). In nonsmokers, PAT reduced MACCE and MACE by 51.5% (3.3% vs. 6.7%, HR = 0.485, 95% CI: 0.277-0.849, p = .011) and 63.5% (1.8% vs. 4.9%, HR = 0.365, 95% CI: 0.178-0.752, p = .006), respectively. When testing p-values for interaction, we found there was no significant interaction of smoking status with treatment effects of PAT (pint-NACE  = .184, pint-bleeding  = .660).

CONCLUSION

Regardless of smoking, PAT reduced the MACE and MACCE, with no significant difference in bleeding. This suggests that PAT was an recommendable regimen to CCS patients after PCI, taking into consideration both ischemic and bleeding risk.

Analysis of the Reactivity of Aspirin and Clopidogrel and Its Influencing Factors in Patients with Coronary Heart Disease at High Altitude

Objective

To evaluate the efficacy of dual-antiplatelet treatment (DAPT) in patients with coronary heart disease (CHD) at high altitude by using thrombelastogram (TEG) and to analyze the related biochemical factors affecting drug reactivity.

Methods

Totally 118 CHD patients who admitted to the Qinghai People's Hospital from September 2019 to September 2020 were enrolled in the group. Those people have lived in Qinghai for a long time. Seven days after DAPT, venous blood was collected on an empty stomach in the early morning of the next day; blood routine, coagulation function, and biochemical items were tested. Thrombelastogram (TEG) was used to draw curves to calculate platelet, coagulation and fibrinolysis functions, and drug inhibition rate. Patients were divided into the aspirin resistance (AR) group, clopidogrel resistance (CR) group, dual-antiplatelet drug resistance (DAR) group, and drug-sensitive group according to different inhibition rates. The drug efficacy was analyzed, and the clinical data, biochemical indexes, and TEG parameters of each group were compared to identify the risk factors of drug resistance.

Results

Those 118 CHD patients at high altitude were incorporated into the study, ranging from 38 to 84 years of age, including 81 males (68.64%) and 37 females (31.36%). The platelet function and coagulation-fibrinolysis function were detected by TEG, and MA_THROMBI, MA_ADP, and MA_AA were higher than the reference range. There were 82 cases (69.49%) of drug resistance, 36 cases (32.53%) of drug sensitivity, 17 cases (14.41%) of AR alone, and 16 cases (12.71%) of CR alone. There was no significant difference in age, gender, BMI, oxygen saturation, TG, GFR, and history of diabetes and hypertension between ACS and CCS groups (P > 0.05). PLT and FIB in the ACS group were higher than those in the CCS group, and the difference was statistically significant (P < 0.05). In addition, MA_THROMBIN, MA_FIBRIN, E, A, A30, and coagulation composite index were also higher than those in the CCS group, with a statistically significant difference (P < 0.05). Univariate analysis and logistic regression analysis suggested that age, HbA1c, FBG, and diabetes were the main factors of drug resistance.

Conclusion

Antiplatelet drugs aspirin and clopidogrel resistance are associated with increased age, elevated HbA1c and FBG, and diabetes. Therefore, it is necessary to take reasonable treatment measures based on the actual situation of patients.

Efficacy and safety of ticagrelor versus prasugrel in smokers and nonsmokers with acute coronary syndromes

BACKGROUND

The efficacy and safety of ticagrelor versus prasugrel according to smoking status in patients with acute coronary syndromes (ACS) are not known. We assessed the efficacy and safety of ticagrelor versus prasugrel according to smoking status in patients with ACS undergoing invasive management.

METHODS

This pre-specified analysis of the ISAR-REACT 5 trial included 1349 smokers and 2652 nonsmokers randomized to receive ticagrelor or prasugrel. The primary endpoint was the incidence of death, myocardial infarction, or stroke; the secondary endpoint was the incidence of Bleeding Academic Research Consortium (BARC) type 3 to 5 bleeding (both endpoints assessed at 12 months).

RESULTS

There was no significant treatment arm-by-smoking status interaction regarding the efficacy outcome. The primary endpoint occurred in 47 patients (7.0%) in the ticagrelor group and 41 patients (6.2%) in the prasugrel group in smokers (hazard ratio [HR] = 1.15; 95% confidence interval [CI] 0.76-1.75; P = 0.510) and in 133 patients (10.2%) in the ticagrelor group and 94 patients (7.2%) in the prasugrel group in nonsmokers (HR = 1.44 [1.10-1.87]; P = 0.007; P for interaction = 0.378). The secondary endpoint occurred in 27 patients (4.6%) in the ticagrelor group and 33 patients (5.6%) in the prasugrel group in smokers (HR = 0.81 [0.49-1.35]; P = 0.412) and in 66 patients (6.0%) in the ticagrelor group and 46 patients (4.4%) in the prasugrel group in nonsmokers (HR = 1.38 [0.94-2.01]; P = 0.097).

CONCLUSIONS

In patients with ACS undergoing an invasive management strategy, the smoking status did not significantly interact with the relative treatment effect of ticagrelor vs. prasugrel.

CLINICAL TRIAL REGISTRATION

NCT01944800.

Assessing platelet reactivity after drug eluting stent implantation: state of the art

Introduction: Platelets play a pivotal role in the occurrence of recurrent ischemic events in coronary artery disease patients who are treated with drug-eluting stents and are on dual antiplatelet therapy (DAPT).Areas covered: High platelet reactivity (HPR) to adenosine diphosphate during clopidogrel therapy is a strong predictor of post-stenting ischemic event occurrences. However, uniform use of potent P2Y₁₂ receptors blockers to overcome HPR is associated with elevated bleeding risk. Selective de-escalation of P2Y₁₂ receptor blocker therapy based on PFT in patients with acute coronary syndrome treated with stenting has been shown to be associated with a similar risk of ischemic event occurrence but with a reduced risk of bleeding. This review aims to discuss the role of PFT in guiding DAPT in patients treated with DES. We searched electronic databases from January 2000 to December 2019 for literatures evaluating the role of platelet function assessment after drug eluting stents.Expert opinion: Platelet function guided therapy improves patient outcomes by lessening bleeding and limiting the overuse of highly potent P2Y₁₂ inhibitors. Interest in this area of de-escalation of therapy will likely grow as the consequences of bleeding are better recognized and the cost of healthcare gains greater focus.