"Stent Thrombosis With Ticagrelor Versus Clopidogrel in Patients With Acute Coronary Syndromes"
Circ Jul 30 (online)
http://circ.ahajournals.org/content/128/10/1055.abstract 
"Conclusion—Ticagrelor compared with clopidogrel reduces the incidence of stent thrombosis in patients with acute coronary syndromes, with consistent benefit across a broad range of patient, stent, and treatment characteristics."