The aim of the present study was to investigate the long-term impact of early intravenous
metoprolol in
ST-segment elevation myocardial infarction (
STEMI) patients in terms of left ventricular (LV) strain with feature-tracking cardiovascular magnetic resonance (CMR) and its association with prognosis. A total of 270 patients with first anterior
STEMI enrolled in the randomized METOCARD-CNIC clinical trial, assigned to receive up to 15 mg intravenous
metoprolol before primary
percutaneous coronary intervention versus conventional
STEMI therapy, were included. LV global circumferential (GCS) and longitudinal (GLS) strain were assessed with feature-tracking CMR at 1 week after
STEMI in 215 patients. The occurrence of
major adverse cardiac events (
MACE) at 5-year follow-up was the primary end point. Among 270 patients enrolled, 17 of 139 patients assigned to
metoprolol arm and 31 of 131 patients assigned to control arm experienced
MACE (hazard ratio [HR] 0.500, 95% confidence interval [CI] 0.277 to 0.903; p = 0.022). Impaired LV GCS and GLS strain were significantly associated with increased occurrence of
MACE (GCS: HR 1.208, 95% CI 1.076 to 1.356, p =0.001; GLS: HR 1.362, 95% CI 1.180 to 1.573, p < 0.001). On multivariable analysis, LV GLS provided incremental prognostic value over late
gadolinium enhancement (LGE) and LV ejection fraction (LVEF) (LGE + LVEF chi-square = 12.865, LGE + LVEF + GLS chi-square = 18.459; p =0.012). Patients with GLS ≥-11.5% (above median value) who received early intravenous
metoprolol were 64% less likely to experience
MACE than their counterparts with same degree of GLS impairment (HR 0.356, 95% CI 0.129 to 0.979; p = 0.045). In conclusion, early intravenous
metoprolol has a long-term beneficial prognostic effect, particularly in patients with severely impaired LV systolic function. LV GLS with feature-tracking CMR early after
percutaneous coronary intervention offers incremental prognostic value over conventional CMR parameters in risk stratification of
STEMI patients.