Clopidogrel Hyperresponsiveness and Hemorrhagic Complications Using On-Label Clopidogrel Dosing after Pipeline...

Area of Science:

• Neuroendovascular Surgery
• Pharmacology
• Clinical Outcomes

Background:

• Clopidogrel hyperresponsiveness is linked to bleeding risks after neuroendovascular procedures.
• Optimal clopidogrel dosing and timing for minimizing complications remain under investigation.
• Hemorrhagic complications are a significant concern following flow diversion procedures.

Purpose of the Study:

• To investigate hemorrhagic complications associated with standard clopidogrel doses after Pipeline Embolization Device (PED) placement.
• To compare bleeding rates between clopidogrel hyperresponsive and normoresponsive patients.
• To determine the timing of hemorrhagic complications in relation to neuroendovascular procedures.

Main Methods:

• Retrospective cohort study of 148 adult patients undergoing PED flow diversion.
• Patients were categorized based on clopidogrel response using VerifyNow P2Y12 reaction units (PRU).
• Hyperresponsive (PRU ≤ 70) and normoresponsive (PRU 71-194) groups were compared for hemorrhagic complications.

Main Results:

• 36.5% of patients were clopidogrel hyperresponsive (PRU ≤ 70).
• No hemorrhagic complications occurred in the hyperresponsive group; 5 occurred in the normoresponsive group (P=0.09).
• Intracranial hemorrhages were most common (60%), occurring intra-procedure or within the first week. Age > 60 was a predictor (P=0.004).

Conclusions:

• Findings contradict prior literature, showing fewer bleeding complications in clopidogrel hyperresponders.
• Hemorrhagic complications predominantly occurred in the acute peri-procedural period.
• Age over 60 is a significant risk factor for bleeding complications after PED placement.