Pre-hospital loading with ticagrelor/prasugrel trumps clopidogrel in STEMI patients

Pre-hospital loading with ticagrelor or prasugrel reduces infarct size and greater myocardial salvage index in patients with ST-elevation myocardial infarction (STEMI) relative to clopidogrel, a recent study has found.

The study included STEMI patients who were loaded with either clopidogrel (n=351; mean age, 58.8±10.6 years) or ticagrelor/prasugrel (n=342; mean age, 57.8±10.4 years) in the ambulance before receiving primary percutaneous coronary injury. Cardiac magnetic resonance (CMR) was used in the calculation of infarct size and the myocardial salvage index. Outcomes were measured at baseline and after 3 months.

At baseline, all CMR findings were comparable between the clopidogrel and ticagrelor/prasugrel groups, except for left ventricular mass index, which was significantly higher in the latter group (p=0.002).

By the 3-month follow-up, infarct size was significantly lower in the ticagrelor/prasugrel group (10.0 vs 12.9 percent of left ventricular mass; p<0.001), while the myocardial salvage index was significantly higher (71 percent vs 66 percent; p<0.001). Left ventricular mass index remained significantly elevated in the ticagrelor/prasugrel group (p=0.003).

These differences were reported despite no significant gaps in the time to CMR between the clopidogrel and ticagrelor/prasugrel groups (p=0.18). Agent choice had no significant effect on left ventricular ejection fraction, and left ventricular end-diastolic and end-systolic volume indices.

“This is a retrospective study with non-prespecified sub-analysis. Antiplatelet treatment was not randomized. No specific data were available on the timing of loading in relation to symptom onset and time of wiring/PCI,” the researchers said, referring to the study’s limitations.