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Background older patients with ST-segment elevation myocardial infarction (STEMI) represent a very high-risk population. Data on the prognostic value of cardiac magnetic resonance (CMR) in this scenario are scarce. Methods the registry comprised 247 STEMI patients over 70 years of age treated with percutaneous intervention and included in a multicenter registry. Baseline characteristics, echocardiographic parameters and CMR-derived left ventricular ejection fraction (LVEF, %), infarct size (% of left ventricular mass) and microvascular obstruction (MVO, number of segments) were prospectively collected. The additional prognostic power of CMR was assessed using adjusted C-statistic, net reclassification index (NRI) and integrated discrimination improvement index (IDI). Results during a 4.8-year mean follow-up, the number of first major adverse cardiac events (MACE) was 66 (26.7%): 27 all-cause deaths and 39 re-admissions for acute heart failure. Predictors of MACE were GRACE score (HR 1.03 [1.02–1.04], P  < 0.001), CMR–LVEF (HR 0.97 [0.95–0.99] per percent increase, P  = 0.006) and MVO (HR 1.24 [1.09–1.4] per segment, P  = 0.001). Adding CMR data significantly improved MACE prediction compared to the model with baseline and echocardiographic characteristics (C-statistic 0.759 [0.694–0.824] vs. 0.685 [0.613–0.756], NRI = 0.6, IDI = 0.08, P  < 0.001). The best cut-offs for independent variables were GRACE score > 155, LVEF < 40% and MVO ≥ 2 segments. A simple score (0, 1, 2, 3) based on the number of altered factors accurately predicted the MACE per 100 person-years: 0.78, 5.53, 11.51 and 78.79, respectively (P  < 0.001). Conclusions CMR data contribute valuable prognostic information in older patients submitted to undergo CMR soon after STEMI. The Older-STEMI–CMR score should be externally validated. [ABSTRACT FROM AUTHOR]

Background: Magnetic resonance imaging (MRI) is the most accurate imaging technique for left ventricular ejection fraction (LVEF) quantification, but as yet the prognostic value of LVEF assessment at any time after ST‐segment elevation myocardial infarction (STEMI) for subsequent major adverse cardiac event (MACE) prediction is uncertain. Purpose: To explore the prognostic impact of MRI‐derived LVEF at any time post‐STEMI to predict subsequent MACE (cardiovascular death or re‐admission for acute heart failure). Study Type: Prospective. Population: One thousand thirteen STEMI patients were included in a multicenter registry. Field Strength/Sequence: 1.5‐T. Balanced steady‐state free precession (cine imaging) and segmented inversion recovery steady‐state free precession (late gadolinium enhancement) sequences. Assessment: Post‐infarction MRI‐derived LVEF (reduced [r]: <40%; mid‐range [mr]: 40%–49%; preserved [p]: ≥50%) was sequentially quantified at 1 week and after >3 months of follow‐up. Statistical Tests: Multi‐state Markov model to determine the prognostic value of each LVEF state (r‐, mr‐ or p‐) at any time point assessed to predict subsequent MACE. A P‐value <0.05 was considered to be statistically significant. Results: During a 6.2‐year median follow‐up, 105 MACE (10%) were registered. Transitions toward improved LVEF predominated and only r‐LVEF (at any time assessed) was significantly related to a higher incidence of subsequent MACE. The observed transitions from r‐LVEF, mr‐LVEF, and p‐LVEF states to MACE were: 15.3%, 6%, and 6.7%, respectively. Regarding the adjusted transition intensity ratios, patients in r‐LVEF state were 4.52‐fold more likely than those in mr‐LVEF state and 5.01‐fold more likely than those in p‐LVEF state to move to MACE state. Nevertheless, no significant differences were found in transitions from mr‐LVEF and p‐LVEF states to MACE state (P‐value = 0.6). Data Conclusion: LVEF is an important MRI index for simple and dynamic post‐STEMI risk stratification. Detection of r‐LVEF by MRI at any time during follow‐up identifies a subset of patients at high risk of subsequent events. Level of Evidence: 2 Technical Efficacy Stage: 2 [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is available in the text. Background: Cardiac magnetic resonance (CMR) permits robust risk stratification of discharged ST-segment–elevation myocardial infarction patients, but its indiscriminate use in all cases is not feasible. We evaluated the utility of left ventricular ejection fraction (LVEF) by echocardiography for a selective use of CMR after ST-segment–elevation myocardial infarction. Methods: Echocardiography and CMR were performed in 1119 patients discharged for ST-segment–elevation myocardial infarction included in a multicenter registry. The prognostic power of CMR beyond echocardiography-LVEF was assessed using adjusted C statistic, net reclassification improvement index, and integrated discrimination improvement index. Results: During a 4.8-year median follow-up, 136 (12%) first major adverse cardiac events (MACE) occurred (47 cardiovascular deaths and 89 readmissions for acute heart failure). In the entire group, CMR-LVEF (but not echocardiography-LVEF) independently predicted MACE occurrence. The MACE rate significantly increased only in patients with CMR-LVEF<40% (≥50%: 7%, 40%–49%: 9%, <40%: 27%, P <0.001). Most patients displayed echocardiography-LVEF≥50% (629, 56%), and they had a low MACE rate (57/629, 9%). In patients with echocardiography-LVEF<50% (n=490, 44%), the MACE rate was also low in those with CMR-LVEF≥40% (24/278, 9%) but significantly increased in patients with CMR-LVEF<40% (55/212, 26%; P <0.001). Compared with echocardiography-LVEF, CMR-LVEF significantly improved MACE prediction in the group of patients with echocardiography-LVEF<50% (C statistic, 0.80 versus 0.72; net reclassification improvement index, 0.73; integrated discrimination improvement index, 0.10) but not in those with echocardiography-LVEF≥50% (C statistic 0.66 versus 0.66; net reclassification improvement index, 0.17; integrated discrimination improvement index, 0.01). Conclusions: A straightforward strategy based on a selective use of CMR for risk prediction in ST-segment–elevation myocardial infarction patients with echocardiography-LVEF<50% can provide insights into patient care. The cost-effectiveness of this approach, as well as the direct implications in clinical management, should be further explored. [ABSTRACT FROM AUTHOR]

Cardiac magnetic resonance (CMR) performed early after ST-segment elevation myocardial infarction (STEMI) can improve major adverse cardiac event (MACE) risk prediction. We aimed to create a simple clinical-CMR risk score for early MACE risk stratification in STEMI patients. We performed a multicenter prospective registry of reperfused STEMI patients (n = 1118) in whom early (1-week) CMR-derived left ventricular ejection fraction (LVEF), infarct size and microvascular obstruction (MVO) were quantified. MACE was defined as a combined clinical endpoint of cardiovascular (CV) death, non-fatal myocardial infarction (NF-MI) or re-admission for acute decompensated heart failure (HF). During a median follow-up of 5.52 [2.63–7.44] years, 216 first MACE (58 CV deaths, 71 NF-MI and 87 HF) were registered. Mean age was 59.3 ± 12.3 years and most patients (82.8%) were male. Based on the four variables independently associated with MACE, we computed an 8-point risk score: time to reperfusion >4.15 h (1 point), GRACE risk score > 155 (3 points), CMR-LVEF <40% (3 points), and MVO >1.5 segments (1 point). This score permitted MACE risk stratification: MACE per 100 person-years was 1.96 in the low-risk category (0–2 points), 5.44 in the intermediate-risk category (3–5 points), and 19.7 in the high-risk category (6–8 points): p < 0.001 in multivariable Cox survival analysis. A novel risk score including clinical (time to reperfusion >4.15 h and GRACE risk score > 155) and CMR (LVEF <40% and MVO >1.5 segments) variables allows for simple and straightforward MACE risk stratification early after STEMI. External validation should confirm the applicability of the risk score. • CMR is being increasingly used after STEMI for prognostic assessment. • Clinical variables (time to reperfusion and GRACE score) predict MACE occurrence. • Early CMR variables (LVEF and microvascular obstruction) also improve risk prediction. • A simple clinical-CMR risk score including these variables enabled effective MACE risk stratification. • The implications of risk stratification by this score early after STEMI should be further explored. [ABSTRACT FROM AUTHOR]