Prognostic implications of peak early diastolic strain rate (PEDSR) by feature-tracking cardiac magnetic resonance in patients with st-elevation myocardial infarction

Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): the National Key Research and Development Program of China OnBehalf Renji Hospital Affiliated to Medical College of Shanghai Jiaotong University Background：The prognostic value of Peak Early Diastolic Strain Rate (PEDSR) measured by Cardiac Magnetic Resonance (CMR) in ST-Elevation Myocardial Infarction (STEMI) is not clear. Methods：420 first-STEMI patients from the EARLY Assessment of MYOcardial Tissue Characteristics by CMR in STEMI (EARLY-MYO-CMR) registry (NCT03768453) and 40 normal people were enrolled and followed up. The patients received timely percutaneous coronary intervention (PCI) within 12h and CMR within 1 week (median,5 days; range, 2-7 days) after infarction. LV circumferential, radial, longitudinal PEDSR and other routine CMR parameters were measured. Clinical end point was a composite major adverse cardiovascular events (MACEs) including cardiovascular death, re-infarction and re-hospitalization for heart failure. Results：During follow-up (median: 52 months, inter-quartile range: 29–78 months), 73 (17.4%) patients experienced a MACE event. Compared with normal people, STEMI patients had lower PEDSR (circumf. PEDSR 0.77 vs. 1.27%/s, P < 0.001). Patients who developed MACEs also had lower PEDSR than patients who didn’t (circumf. PEDSR 0.64 vs. 0.78%/s, P < 0.001). Circumf. PEDSR can significantly predict MACEs with an AUC of 0.659 (95%CI 0.587-0.731, P < 0.001) which is not inferior to LVEF (0.659 vs. 0.651, P = 0.843), LVIS (0.659 vs. 0.661, P = 0.678) and LVMVO (0.659 vs. 0.666, P = 0.600). Circumf. PEDSR ≤ 0.665%/s is the independent predictive factor of MACEs in clinical (HR 2.099 [95%CI 1.273-3.461], P = 0.004) and CMR models (HR 1.795 [95%CI 1.065-3.026], P = 0.028). In Kaplan-Meier curve, patients with impaired PEDSR are more likely to experience MACEs (P < 0.001). When subdivided by LVEF, PEDSR still makes a significant difference to MACEs in patients with LVEF > 50.28% (P = 0.003) but not in reduced LVEF patients (P = 0.204). PEDSR is also incremental to LVEF (Continuous NRI 0.515 [95%CI 0.268-0.763], P < 0.001), LVIS (Continuous NRI 0.576 [95%CI 0.330-0.822], P < 0.001), and LVMVO (Continuous NRI 0.576 [95%CI 0.330-0.822], P < 0.001). Finally, worse TIMI flow post-PCI (HR 3.353 [95%CI 1.603-7.016], P = 0.001) and LVEF (HR 0.920 [95%CI 0.900, 0.940], P < 0.001) are the risk factors for PEDSR impairment. Conclusions：CMR-derived PEDSR can significantly predict MACEs with the discriminative power not inferior to LVEF, LVIS and LVMVO. Circumf. PEDSR ≤ 0.665%/s is an independent predictive factor of MACEs and is incremental in the prognostic risk stratification of STEMI.