Determinants and Clinical Outcomes of Extended Dual Antiplatelet Therapy over 3 Years after Drug-Eluting Stent Implantation: A Retrospective Analysis

Is the duration of dual antiplatelet therapy (DAPT) excessive in post-angioplasty in chronic coronary syndrome? Data from the France-PCI registry (2014-2019)

Background

while the duration of dual antiplatelet therapy (DAPT) following coronary angioplasty for chronic coronary syndrome (CCS) recommended by the European Society of Cardiology has decreased over the last decade, little is known about the adherence to those guidelines in clinical practice in France.

Aim

To analyze the real duration of DAPT post coronary angioplasty in CCS, as well as the factors affecting this duration.

Methods

Between 2014 and 2019, 8.836 percutaneous coronary interventions for CCS from the France-PCI registry were evaluated, with 1 year follow up, after exclusion of patients receiving oral anticoagulants, procedures performed within one year of an acute coronary syndrome, and repeat angioplasty.

Results

Post-percutaneous coronary intervention (PCI) DAPT duration was > 12 months for 53.1% of patients treated for CCS; 30.5% had a DAPT between 7 and 12 months, and 16.4% a DAPT ≤ 6 months. Patients with L-DAPT (>12 months) were at higher ischemic risk [25.0% of DAPT score ≥2 vs. 18.8% DAPT score ≥2 in S&I-DAPT group (≤12 months)]. The most commonly used P2Y12 inhibitor was clopidogrel (82.2%). The prescription of ticagrelor increased over the period.

Conclusions

post-PCI DAPT duration in CCS was higher than international recommendations in the France PCI registry between 2014 and 2019. More than half of the angioplasty performed for CCS are followed by a DAPT > 12 months. Ischemic risk assessment influences the duration of DAPT. This risk is probably overestimated nowadays, leading to a prolongation of DAPT beyond the recommended durations, thus increasing the bleeding risk.

A Case of Ticagrelor Resistance

Ticagrelor is a directly acting cyclopentyltriazolo-pyrimidine which does not require conversion into an active metabolite. It inhibits the P2Y₁₂ receptors on platelets reversibly. Unlike clopidogrel and prasugrel, resistance to ticagrelor is rarely reported. Various mechanisms have been proposed for this resistance. The case of a 62-year-old man with diabetes who had undergone index percutaneous coronary intervention (PCI) 22 days previously is described. The patient presented to us with stent thrombosis. His primary PCI was successfully carried out with a drug-eluting stent. He showed resistance to ticagrelor on thromboelastography platelet mapping. He responded well to prasugrel (another P2Y₁₂ inhibitor) in combination with aspirin.

LEARNING POINTS

Ticagrelor is a pro-drug and directly inhibits P2Y₁₂ receptors.This makes ticagrelor less susceptible to drug-drug interactions or pharmacogenetic influences.Thromboelastography platelet mapping measures the physical properties of clot formation and can reveals platelet resistance to various P2Y₁₂ inhibitors, including ticagrelor.