TREAT: Are we one step closer? by Rajesh M. Dave, MD
It is well established that Primary PCI in a timely fashion leads to the best outcomes in patients with STEMI. However, in large part of the world fibrinolytic therapy is the mainstay in treatment of STEMI. Moreover, the availability of PCI and optimal PCI techniques in STEMI varies greatly by region and operators. Henceforth, pharmacotherapy induced lysis has significant impact on cardiovascular health of large population globally. Antiplatelet therapy is a major component of management of acute myocardial infarction. In certain studies, fibrinolysis has shown to cause platelet activation. Ticagrelor is a more potent and faster P2Y12 Inhibitor than Clopidogrel and may have advantages in the setting of fibrinolysis.
In the study of Platelet Inhibition and Patients outcomes (PLATO), which evaluated patients with STEMI as well as NSTEMI, immediate use of Ticagrelor has been shown to be superior to Clopidogrel with small increase in bleeding risk. TREAT Trial examined question of safety of Ticagrelor in STEMI patients treated with Fibrinolysis. Converting patient to Ticagrelor after initial exposure to Clopidogrel in nearly 90% of patients is safe and not inferior for major bleeding. Major bleeding at 30 days, per thrombolysis in myocardial infarction (TIMI) major bleeding criteria, occurred in 0.73% of patients receiving Ticagrelor and 0.69% of those receiving Clopidogrel (absolute difference, 0.04%; 95%CI, −0.49% to 0.58%; p < 0.001 for no inferiority). Fatal (0.16% vs 0.11%; p = 0.67) and intracranial (0.42%vs 0.37%; p = 0.82) bleeding events were not different between the study groups. Minor bleeding occurred in 3.24% of Ticagrelor patients and 2.01% of Clopidogrel patients (p = 0.02).
However, there are few limitations of the study. First, large number of patients in this trial had Clopidogrel pre-exposure. Secondly, only patients younger than age 75 years were included. In my opinion, the most important question is whether initial loading of Ticagrelor with fibrinolysis would lead to better outcomes without increasing bleeding. I am however comforted that even patients with pre-exposure to Clopidogrel did not have greater bleeding risk with conversion to Ticagrelor in TREAT bringing us one step closer to the ultimate question about outcome as stated above. We will await future investigations for this important question.