Assessing the Clinical Treatment Dynamics of Antiplatelet Therapy Following Acute Coronary Syndrome and Percutaneous Coronary Intervention in the US

Stent thrombosis in the setting of ST-segment elevation acute myocardial infarction in the contemporary practice: results from the TOTAL randomized trial

The aim was to know the risk and predictive factors of stent thrombosis (ST) in patients with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI) in the contemporary practice. The TOTAL [ThrOmbecTomy with percutaneous coronary intervention (PCI) versus PCI ALone] randomized trial, being the largest trial performed in the setting of STEMI with a general application of the recent recommendations, represents a unique opportunity to know the current real-world incidence of ST as well as its associated factors. A total of 10 064 patients that received ≥1 coronary stent in the TOTAL trial comprise the study population. The risk, predictive factors, and clinical implications of ST was studied. During 1-year follow-up, 155 patients (1.54%) suffered definitive or probable ST (59 acute, 67 subacute, and 29 late). Previous infarction, the number of stents, the previous use of clopidogrel, and the use of diuretics at discharge were independent predictors for ST, whereas the use of upfront glycoprotein IIb/IIIa inhibitors, radial access, and treatment with statins at discharge were independent protective factors. The number of stents, stent diameter, upfront treatment with IIb/IIIa inhibitors, previous treatment with clopidogrel, and treatment with statins at discharge were independently associated with the risk of early ST. Only previous infarction was associated with the risk of late ST. In the contemporary practice, ST still constitutes a frequent complication of primary PCI for STEMI, occurring in 1.5% of patients. Independent predictors are different depending on the time of ST.

Genetic Determinants of Response to P2Y12 Inhibitors and Clinical Implications

The CYP2C19 enzyme metabolizes clopidogrel, a prodrug, to its active form. Approximately 30% of individuals inherit a loss-of-function (LoF) polymorphism in the CYP2C19 gene, leading to reduced formation of the active clopidogrel metabolite. Reduced clopidogrel effectiveness has been well documented in patients with an LoF allele following an acute coronary syndrome or percutaneous coronary intervention. Prasugrel or ticagrelor is recommended in those with an LoF allele as neither is affected by CYP2C19 genotype. Although data demonstrate improved outcomes with a CYP2C19-guided approach to P2Y12 inhibitor selection, genotyping has not yet been widely adopted in clinical practice.

Patient and Physician Perspectives on the Benefits and Risks of Antiplatelet Therapy for Acute Coronary Syndrome

This article is co-authored by a patient with acute coronary syndrome (ACS) who is receiving long-term antiplatelet therapy in the USA and a cardiologist who routinely treats patients with ACS. The patient describes his experience from diagnosis to the present day and discusses his concerns regarding treatment and management of the condition, including the balance between the benefits and risks of antiplatelet therapy. The patient also describes his work as an advocate for cardiac health. The physician perspective on treating and managing patients with ACS is provided by a cardiologist based in the USA who is and was not involved in this patient's care. The physician reviews the benefits and risks of antiplatelet therapies for the treatment of patients with ACS and discusses his own clinical experience of managing these patients, including how issues such as treatment adherence, as well as the potential inertia to prescribing certain medications that may be seen among physicians, could be overcome.

Precision Antiplatelet Therapy after Percutaneous Coronary Intervention (Precision PCI) Registry - Informing optimal antiplatelet strategies

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor (clopidogrel, prasugrel, or ticagrelor) is indicated after percutaneous coronary intervention (PCI) to reduce the risk of atherothrombotic events. Approximately 30% of the US population has a CYP2C19 no-function allele that reduces the effectiveness of clopidogrel, but not prasugrel or ticagrelor, after PCI. We have shown improved outcomes with the integration of CYP2C19 genotyping into clinical care to guide the selection of prasugrel or ticagrelor in CYP2C19 no-function allele carriers. However, the influence of patient-specific demographic, clinical, and other genetic factors on outcomes with genotype-guided DAPT has not been defined. In addition, the impact of genotype-guided de-escalation from prasugrel or ticagrelor to clopidogrel in patients without a CYP2C19 no-function allele has not been investigated in a diverse, real-world clinical setting. The Precision Antiplatelet Therapy after Percutaneous Coronary Intervention (Precision PCI) Registry is a multicenter US registry of patients who underwent PCI and clinical CYP2C19 testing. The registry is enrolling a diverse population, assessing atherothrombotic and bleeding events over 12 months, collecting DNA samples, and conducting platelet function testing in a subset of patients. The registry aims to define the influence of African ancestry and other patient-specific factors on clinical outcomes with CYP2C19-guided DAPT, evaluate the safety and effectiveness of CYP2C19-guided DAPT de-escalation following PCI in a real-world setting, and identify additional genetic influences of clopidogrel response after PCI, with the ultimate goal of establishing optimal strategies for individualized antiplatelet therapy that improves outcomes in a diverse, real-world population.

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.

Impact of Society Guidelines on Trends in Use of Newer P2Y12 Inhibitors for Patients With Acute Coronary Syndromes Undergoing Percutaneous Coronary Intervention

BACKGROUND

Over the past decade, major society guidelines have recommended the use of newer P2Y12 inhibitors over clopidogrel for those undergoing percutaneous coronary intervention for acute coronary syndrome. It is unclear what impact these recommendations had on clinical practice.

METHODS AND RESULTS

All percutaneous coronary intervention procedures (n=534 210) for acute coronary syndrome in England and Wales (April 1, 2010, to March 31, 2022) were retrospectively analyzed, stratified by choice of preprocedural P2Y12 inhibitor (clopidogrel, ticagrelor, and prasugrel). Multivariable logistic regression models were used to examine odds ratios of receipt of ticagrelor and prasugrel (versus clopidogrel) over time, and predictors of their receipt. Overall, there was a significant increase in receipt of newer P2Y12 inhibitors from 2010 to 2020 (2022 versus 2010: ticagrelor odds ratio, 8.12 [95% CI, 7.67-8.60]; prasugrel odds ratio, 6.14 [95% CI, 5.53-6.81]), more so in ST-segment-elevation myocardial infarction than non-ST-segment-elevation acute coronary syndrome indication. The most significant increase in odds of receipt of prasugrel was observed between 2020 and 2022 (P<0.001), following a decline/plateau in its use in earlier years (2011-2019). In contrast, the odds of receipt of ticagrelor significantly increased in earlier years (2012-2017, Ptrend<0.001), after which the trend was stable (Ptrend=0.093).

CONCLUSIONS

Over a 13-year-period, there has been a significant increase in use of newer P2Y12 inhibitors, although uptake of prasugrel use remained significantly lower than ticagrelor. Earlier society guidelines (pre-2017) were associated with the highest rates of ticagrelor use for non-ST-segment-elevation acute coronary syndrome and ST-segment-elevation myocardial infarction cases while the ISAR-REACT 5 (Prospective, Randomized Trial of Ticagrelor Versus Prasugrel in Patients With Acute Coronary Syndrome) trial and later society guidelines were associated with higher prasugrel use, mainly for ST-segment-elevation myocardial infarction indication.