The impact of in-hospital P2Y12 inhibitor switch in patients with acute coronary syndrome

Background/purpose: Dual antiplatelet therapy (DAPT) varies after placement of drug-eluting stents (DES) in patients presenting with acute coronary syndromes (ACS). Our aim was to study patient characteristics and predictors of switching, in-hospital or at discharge, from clopidogrel (CLO) to ticagrelor (TIC) or vice versa.

Methods/materials: The study population included patients with ACS who had DES and initially received either CLO or TIC between January 2011 and December 2017. Patients were divided into 4 groups based on initial DAPT choice and whether DAPT was switched in-hospital or during discharge. Clinical outcomes of interest were bleeding events, need for anticoagulation, and need for in-hospital coronary artery bypass graft (CABG).

Results: We identified 2837 patients who received DES and started on DAPT. DAPT switch from 1 P2Y12 inhibitor to another occurred in 9%, either in-hospital or at discharge. Of 1834 patients started on CLO, 112 were switched to TIC. Of 1003 patients started on TIC, 142 were switched to CLO. The need for in-hospital CABG was 7.8% in the TIC-CLO group compared to none in the CLO-TIC group (p = 0.002). Adjusted for covariates, the TIC-CLO group was 3 times more likely to need anticoagulation with warfarin than the CLO-CLO group (p < 0.001) and over 5 times more likely than the CLO-TIC group and the TIC-TIC group (p < 0.005 for both).

Conclusions: Switching from 1 generation P2Y12 inhibitor to another does occur in ACS patients. Clinical needs such as in-hospital CABG or oral anticoagulation upon discharge are real and dictate the switch from TIC to CLO.

Summary: A single-center observational study of 2837 patients with acute coronary syndromes treated with drug-eluting stents found that some do get switched from one generation P2Y12 inhibitor to another. The switch from clopidogrel to ticagrelor is driven by clinical needs such as in-hospital coronary artery bypass grafting or the need for oral anticoagulation upon discharge.