No superiority of ticagrelor over prasugrel in remote myocardial inflammation in patients with acute myocardial infarction with ST elevation: a CMR T1 and T2 mapping study
Authors: Zugwitz D , Everaars H , Van Der Hoeven N.W , Janssens G.N , Vart P , Van Leeuwen M.A.H , Van Rossum A.C , El Messaoudi S , Riksen N.P , Van Royen N , Nijveldt R 
Published: November 2020

Abstract

Background
A number of studies suggest that acute myocardial ischaemia triggers a non-specific systemic inflammatory response of remote myocardium through the increase of plasma concentrations of acute-phase proteins, which causes myocardial oedema. As ticagrelor has been shown to significantly decrease the circulating levels of several pro-inflammatory cytokines in patients after acute myocardial infarction with ST elevation (STEMI), we sought to investigate a potential suppressive effect of ticagrelor over prasugrel on cardiac magnetic resonance (CMR) T1 and T2 values in remote myocardium.

Methods
Ninety patients presenting with acute STEMI were prospectively included and randomised to receive either ticagrelor or prasugrel maintenance treatment after successful primary percutaneous coronary intervention (PPCI). The patients underwent CMR 2–7 days after the PPCI. Studies were done on a 1.5 T clinical scanner, the protocol included long and short axis cine imaging, T1 mapping through the infarct core using a single breath-hold Shortened Modified Look-Locker Inversion Recovery (ShMOLLI), T2 mapping and late gadolinium enhancement imaging.

Results
After excluding 30 patients due to either missing images or insufficient quality of T1 or T2 maps, 60 patients were included in our analysis. Of those, 29 patients have been randomised to the ticagrelor arm and 31 patients to the prasugrel arm of the study. The mean age at inclusion was 61±10 years, 81.7% of included patients were men, the distribution was even between the two groups. There were no statistically significant differences between groups regarding past medical history and medication prior to the inclusion in the study.
CMR scans were performed 5.03±1.96 days after successful PPCI in the ticagrelor group, and 5.10±0.87 days in the prasugrel group.
Remote myocardium T1: The mean T1 value of the remote myocardium was 937±27 ms in the ticagrelor group and 936±23 ms in the prasugrel group, showing no statistical difference (p=0.85) between the groups receiving different P2Y12 inhibitor after PPCI.
Remote myocardium T2: The mean T2 value of the remote myocardium was 53.8±4.6 ms in the ticagrelor group and 53.6±4.7 ms in the prasugrel group, showing no statistical difference (p=0.86) between compared groups.
Both T1 and T2 values of the remote myocardium were above normal values published in literature.

Conclusion
In patients with STEMI after PPCI, ticagrelor maintenance therapy did not show superiority to prasugrel in preventing early remote myocardial inflammation as assessed by T1 and T2 mapping.
Additionally, findings support the premise of remote myocardial oedema following STEMI.

Funding Acknowledgement
Type of funding source: Other. Main funding source(s): Presented abstract is from a sub-study of the REDUCE-MVI study, which was conducted with financial support from Astra Zeneca through an unrestricted research grant. In addition, the study was financed by the Ministry of Economic Affairs of the Netherlands by means of a PPP Allowance made available by the Top Sector Life Sciences & Health to stimulate public-private partnerships. The first author was awarded the ESC training grant in 2019; this research was conducted during the training for which the grant was awarded.