Prognostic implications of left ventricular torsion by feature-tracking cardiac magnetic resonance in patients with ST-elevation myocardial infarction

Abstract

Abstract 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 implications of left ventricular (LV) torsion on the long-term prognosis of patients with acute ST-elevation myocardial infarction (STEMI) is not clear. Methods We analyzed Cardiac Magnetic Resonance (CMR) images and followed up 420 first STEMI patients from the EARLY Assessment of MYOcardial Tissue Characteristics by CMR in STEMI (EARLY-MYO-CMR) registry (NCT03768453). These patients received timely primary percutaneous coronary intervention (PCI) within 12h and CMR examination within 1 week (median,5 days; range, 2-7 days) after infarction. Besides, CMR images of 40 normal people were enrolled as the control group. LV torsion, torsion rate and other conventional CMR indexes were measured. Ultrasound cardiogram examinations were performed in the acute phase and 1 year post-STEMI to assess LV remodeling (≥ 20% increase in LV end-diastolic volume). Primary end point was composite major adverse cardiac and cerebrovascular events (MACCEs) including cardiovascular death, re-infarction, re-hospitalization for heart failure and stroke. Secondary end points were the formation of LV aneurysm/thrombus in hospital as well as LV remodeling at 1 year post-STEMI. Results During follow-up (median: 52 months, inter-quartile range: 29–78 months), 80 patients developed MACCEs. Compared with normal people, patients with STEMI had more decreased LV torsion (P < 0.001) and torsion rate (P = 0.033). Patients who experienced MACCEs had more impaired LV torsion (P < 0.001) and torsion rate (P < 0.001) than those who didn’t. LV torsion ≤ 0.876 deg/cm in the acute phase of STEMI was an independent predictive factor of MACCE (P = 0.001) and LV remodeling (P = 0.001). Patients with impaired LV torsion were more likely to experience MACCEs (P < 0.001). The impairment of LV torsion was also associated with the higher incidence of LV aneurysm (P < 0.001) and thrombus (P = 0.006). The addition of LV torsion to a risk model comprising LV ejection fraction (LVEF), infarct size (IS), and microvascular obstruction (MVO) led to a net reclassification improvement (continuous NRI 0.499 [95% CI, 0.261–0.737]; P < 0.001). Hypertension (P = 0.047), tobacco use (P = 0.005), worse TIMI flow post-PCI (P < 0.001), more extensive IS (P < 0.001) / MVO size (P = 0.002) were associated with the impairment of LV torsion. Conclusions Compared with normal people, patients with STEMI had more decreased LV torsion and torsion rate. LV torsion ≤ 0.876 deg/cm in the acute phase was an independent predictive factor of MACCE and LV remodeling. The addition of LV torsion to a risk model comprising LVEF, LV-IS and LV-MVO significantly improved risk stratification of patients with STEMI .