Effect of discontinuation of ticagrelor and switching-over to other P2Y12 agents in patients with acute coronary syndrome: a single-center real-world experience from India

Discharge of Acute Coronary Syndrome Patients on Sub-Optimal Dual Anti-Platelet Therapy: A Single Center Experience

PURPOSE

To identify and quantify the reasons why acute coronary syndrome (ACS) patients undergoing stenting at the University of New Mexico Hospital (UNMH) were prescribed sub-optimal dual antiplatelet therapy (DAPT) at discharge, and to identify practice patterns that could potentially lead to improved DAPT treatment for these patients.

METHODS

We reviewed electronic medical records and cardiac catheterization records of 326 patients who underwent percutaneous coronary intervention (PCI) at UNMH between January 1, 2021, and June 30, 2022 and identified 229 ACS patients who survived until discharge. Demographic and clinical characteristics relevant to P2Y12 inhibitor selection were obtained from a review of medical records. Pharmacists' notes documenting their efforts to secure appropriate insurance coverage and reasons for discharging patients on clopidogrel rather than ticagrelor/prasugrel were reviewed. Patients discharged on aspirin and clopidogrel underwent review of medical records and cardiac catheterization lab records to determine if the discharge P2Y12 drug was appropriate. Reasons for inappropriate discharge on clopidogrel were categorized as cost/insurance, patient preference, concern for daily adherence to a twice-daily medication, and maintenance of pre-hospital clopidogrel therapy rather than switch to ticagrelor after PCI.

RESULTS

The 229 ACS patients included 87 (38.0%) appropriately discharged on ticagrelor/prasugrel, 63 (27.5%) appropriately discharged on clopidogrel, 75 (32.8%) discharged on sub-optimal clopidogrel, and 4 (1.7%) not discharged on a P2Y12 inhibitor. For patients inappropriately discharged on clopidogrel (n = 75), the most common reasons were cost or lack of insurance (n = 56) and clinical inertia (taking clopidogrel before PCI and maintained on it afterward) (n = 17). Sub-optimal P2Y12 therapy at discharge was significantly associated with lack of insurance (odds ratio 21.5, 95% confidence interval 5.33-156,p < 0.001) but not with ethnicity, age, sex, or diabetes.

CONCLUSION

At the University of New Mexico, a safety-net hospital, increasing financially restricted access to ticagrelor/prasugrel could help up to 24.5% of ACS patients reduce their risk of ischemic events. For patients admitted on clopidogrel DAPT, escalating to ticagrelor/prasugrel could reduce ischemic risk in 7.4%. Expanding and improving healthcare insurance coverage might reduce the frequency of discharge on sub-optimal P2Y12 therapy.

Implications of Pharmacogenetic Testing for Clopidogrel Therapy in a Tertiary Healthcare Hospital in North India

Background Clopidogrel hyporesponsiveness with decreased antiplatelet activity is prevalent in percutaneous coronary intervention (PCI) patients due to reduced function polymorphism in the CYP2C19 enzyme gene which results in poor conversion of this prodrug to an active metabolite. However, pharmacogenetic testing is not part of routine clinical practice in India. Methodology In this retrospective observational study, we observed the prevalence of loss of function (LOF) gene variants of CYP2C19 (*2, *3) in 60 patients undergoing PCI with complex anatomies in a tertiary healthcare hospital in North India. We do not have follow-up data for a few patients. However, the treatment regimen was recorded, and the occurrence of any clinical event was monitored for the remaining 52 patients for six months. Results The mean age of the patients was 61.76 ± 10.14 years. We found that 52% of patients carried these LOF mutations, of which 37% were intermediate metabolizers, while 15% were poor metabolizers of clopidogrel. However, out of 52 patients for whom follow-up data were available, 22 (42.3%) were intermediate metabolizers, while six (11.54%) showed genotypes associated with poor metabolism of clopidogrel. Clopidogrel (75 mg BD) was the primary replacement drug in place of ticagrelor (90 mg BD) during follow-up after four weeks (based on the clinician's discretion). Conclusions No major ischemic event was reported during the follow-up of these 52 patients. The intermediate metabolizers' LOF in one copy of the CYP2C19 gene seems to overcome genetic deficiency with the clopidogrel 75 mg BD regime, which is comparable to maintenance with ticagrelor 90 mg BD. This study can be extrapolated to a larger cohort to observe statistically significant differences among various groups.

De-escalation of Dual Antiplatelet Therapy After Percutaneous Coronary Intervention in Patients With Acute Coronary Syndrome: An Updated Meta-analysis and Trial Sequential Analysis of 21 Studies and 38,741 Patients

ABSTRACT

Dual antiplatelet therapy (DAPT) is recommended among patients with established acute coronary syndrome. In this meta-analysis, we sought to compare the clinical outcomes between de-escalation versus unchanged DAPT based on both randomized controlled trials (RCTs) and observational studies. The primary outcomes were major adverse cardiovascular events for observational studies and net clinical events for RCTs. Four RCTs and 17 observational studies with a total of 38,741 patients were included. Net clinical events were more common with unchanged DAPT than with de-escalation in RCTs [odd ratio (OR): 1.71; 95% confidence interval (CI), 1.21-2.43; I2 = 69.4%], which was mainly due to higher risks of any bleeding (OR: 1.81; 95% CI, 1.14-2.88; I2 = 75.5%) and major bleeding (OR: 1.58; 95% CI, 1.02-2.46; I2 = 0), without significant differences in ischaemic events. However, trial sequential analysis revealed that sufficient information was obtained just for net clinical events, not for respective ischaemic or bleeding events in RCTs. In the analysis based on real-world observational studies, the risks of myocardial infarction (OR: 0.77; 95% CI, 0.61-0.98; I2 = 0) and stroke (OR: 0.42; 95% CI, 0.22-0.81; I2 = 0) were lower with the unchanged DAPT group. Therefore, de-escalation of DAPT led to a marked reduction in net clinical events compared with unchanged DAPT in RCTs, which was mainly due to reduced bleeding events. However, sufficient information for ischaemic events was not obtained. In the analysis based on real-world observational studies, myocardial infarction and stroke were more common with de-escalation, which should arise our attention.