The Effect of Ticagrelor on Platelet Reactivity in Patients with Clopidogrel Resistance Undergoing Neuroendovascular Procedures

Abstract

BACKGROUND AND PURPOSE: Suboptimal platelet inhibition by clopidogrel (clopidogrel resistance) may be associated with high rates of stent thrombosis and ischemic events. Our objective was to determine if ticagrelor, a P2Y 12 receptor inhibitor, can result in platelet inhibition in patients with clopidogrel resistance. METHODS: A thromboelastography-platelet mapping assay was used in all patients undergoing neuroendovascular procedures requiring oral clopidogrel. In patients with suboptimal platelet inhibition (<60%) on clopidogrel, ticagrelor was imitated after an oral bolus of 180 mg followed by 90 mg twice daily and the platelet mapping assay was repeated. The primary endpoint was hemorrhagic complications classified as major (hemoglobin decrease >5 g/dL or intracranial hemorrhage with deficits), minor (hemoglobin decrease 3-5 g/dL or intracranial hemorrhage without residual deficits), or insignificant. RESULTS:Suboptimal platelet inhibition on clopidogrel was seen in 70 of 106 patients undergoing neuroendovascular procedures. There was a significantly higher magnitude of platelet inhibition with ticagrelor compared with clopidogrel in patients with clopidogrel resistance (mean ± SD: 85.90 ± 10.74% vs. 29.26 ± 17.71%; P < .001); 50 of 70 patients showed optimal inhibition. Two patients had major (fatal) hemorrhagic events (both received either intravenous thrombolytics and/or eptifibatide infusion). Three patients had minor hemorrhagic events, and two patients had insignificant hemorrhagic events. Four of seven hemorrhagic events occurred in patients with optimal response to clopidogrel, two occurred in patients with suboptimal response to ticagrelor, and one occurred in a patient with optimal response to ticagrelor. CONCLUSIONS: Oral ticagrelor can augment platelet inhibition in patients who have clopidogrel resistance.

Early Treatment of Ruptured Blood Blister-Like Aneurysms of the Internal Carotid Artery With Flow Diverters Using Single Antiplatelet Therapy: A Single-Center Experience With Long-Term Follow-Up

“…Due to the lack of appropriate platelet inhibition following clopidogrel administration (clopidogrel resistance), which inhibits the P2Y12 adenosine diphosphate (ADP) receptor and has been associated with higher rates of ischemic complications following neuroendovascular procedures ( 39 ), our institutional approach is to use new P2Y12 antagonists for intracranial stenting, especially for FDs. Although DAPT with acetylsalicylic acid plus clopidogrel is still the main choice for FDs, Podlasek et al recently reported in their meta-analyses that new-generation P2Y12 antagonists (ticagrelor and prasugrel) are safe for patients undergoing flow diversion ( 11 ).…”

Vorapaxar as an Alternative for Ticagrelor Resistance in Neuroendovascular Intervention

“…A meta‐analysis of 19 published studies with patients undergoing PED for IA did not find preoperative P2Y 12 reaction unit (PRU) values from VerifyNow P2Y 12 assay helpful in guiding reduction of ischemic or hemorrhagic complications, 11 contradicting a previously reported ideal range of 70–150 12 . As for TEG‐PM, one study evaluating the effect of ticagrelor in neuroendovascular patients with clopidogrel resistance used a seemingly arbitrary cutoff value of <60% ADP receptor inhibition to define suboptimal platelet function 13 . Another study assessing TEG‐PM as a reliable platelet function test in neuroendovascular patients identified an optimal percentage ADP receptor inhibition range of 10%–90% 14 .…”

“…12 As for TEG-PM, one study evaluating the effect of ticagrelor in neuroendovascular patients with clopidogrel resistance used a seemingly arbitrary cutoff value of <60% ADP receptor inhibition to define suboptimal platelet function. 13 Another study assessing TEG-PM as a reliable platelet function test in neuroendovascular patients identified an optimal percentage ADP receptor inhibition range of 10%-90%. 14 Although TEG-PM has not been proven superior to Ver-ifyNow P2Y 12 assay, our institution prefers TEG-PM as we have found it to be more consistent than PRU values.…”

Risk of new cerebral ischemic events in patients with symptomatic internal carotid artery stenosis while awaiting carotid stent placement

“…Twenty patients were transitioned to oral ticagrelor after exhibiting subtherapeutic adenosine diphosphate (ADP) receptor inhibition defined as ADP inhibition <60%. 13 One patient was allergic to aspirin; therefore, he was placed on cilostazol and clopidogrel. One patient was on aspirin and prasugrel for concomitant cardiovascular disease.…”