A Case of Ticagrelor Resistance

Area of Science:

• Cardiology
• Pharmacology
• Hematology

Background:

• Ticagrelor is a direct-acting P2Y12 inhibitor, unlike clopidogrel and prasugrel which are prodrugs.
• Resistance to ticagrelor is infrequently reported, with various proposed mechanisms.
• Platelet function monitoring is crucial in patients undergoing percutaneous coronary intervention (PCI).

Purpose of the Study:

• To report a rare case of ticagrelor resistance.
• To highlight the utility of thromboelastography platelet mapping in identifying P2Y12 inhibitor resistance.
• To demonstrate an alternative treatment strategy in cases of ticagrelor non-responsiveness.

Main Methods:

• Case report of a 62-year-old male patient with diabetes presenting with stent thrombosis post-PCI.
• Thromboelastography platelet mapping was performed to assess platelet inhibition.
• Treatment was switched from ticagrelor to prasugrel in combination with aspirin.

Main Results:

• The patient exhibited resistance to ticagrelor as confirmed by thromboelastography.
• Following the switch to prasugrel and aspirin, the patient showed a positive clinical response.
• This case underscores the potential for rare instances of ticagrelor resistance.

Conclusions:

• Ticagrelor, a direct P2Y12 inhibitor, is generally less prone to resistance than prodrugs.
• Thromboelastography platelet mapping is a valuable tool for detecting resistance to P2Y12 inhibitors.
• Alternative antiplatelet strategies may be necessary for patients resistant to ticagrelor.