Trajectories and determinants of left ventricular ejection fraction after the first myocardial infarction in the current era of primary coronary interventions

Prognostic impact of new-onset atrial fibrillation in myocardial infarction with and without improved ejection fraction

AIMS

Improvement in left ventricular ejection fraction (impEF) often presents in contemporary acute myocardial infarction (AMI) patients. New-onset atrial fibrillation (NOAF) during AMI is an important predictor of subsequential heart failure (HF), while its impact on the trajectory of post-MI left ventricular ejection fraction (LVEF) and prognostic implication in patients with and without impEF remains undetermined. We aimed to investigate the prognostic impacts of NOAF in AMI patients with and without impEF.

METHODS AND RESULTS

Consecutive AMI patients without a prior history of AF between February 2014 and March 2018 with baseline LVEF ≤ 40% and had ≥1 LVEF measurement after baseline were included. ImpEF was defined as a baseline LVEF ≤ 40% and a re-evaluation showed both LVEF > 40% and an absolute increase of LVEF ≥ 10%. Persistently reduced EF (prEF) was defined as the second measurement of LVEF either ≤40% or an absolute increase of LVEF < 10%. The primary endpoint was a major adverse cardiac event (MACE) that was composed of cardiovascular death and HF hospitalization. Cox regression analysis and competing risk analysis were performed to assess the association of post-MI NOAF with MACE. Among 293 patients (mean age: 66.6 ± 11.3 years, 79.2% of males), 145 (49.5%) had impEF and 67 (22.9%) developed NOAF. Higher heart rate (odds ratio [OR]: 0.84, 95% confidence interval [CI]: 0.73-0.97; P = 0.015), prior MI (OR: 0.25, 95% CI: 0.09-0.69; P = 0.008), and STEMI (OR: 0.40, 95% CI: 0.21-0.77; P = 0.006) were independent predictors of post-MI impEF. Within up to 5 years of follow-up, there were 22 (15.2%) and 53 (35.8%) MACE in patients with impEF and prEF, respectively. NOAF was an independent predictor of MACE in patients with impEF (hazard ratio [HR]: 7.34, 95% CI: 2.49-21.59; P < 0.001) but not in those with prEF (HR: 0.78, 95% CI: 0.39-1.55; P = 0.483) after multivariable adjustment. Similar results were obtained when accounting for the competing risk of all-cause death (subdistribution HR and 95% CIs in impEF and prEF were 6.47 [2.32-18.09] and 0.79 [0.39-1.61], respectively).

CONCLUSIONS

The NOAF was associated with an increased risk of cardiovascular outcomes in AMI patients with impEF.

Iron deficiency and all-cause mortality after myocardial infarction

BACKGROUND

Data on the clinical significance of iron deficiency (ID) in patients with myocardial infarction (MI) are conflicting. This may be related to the use of various ID criteria. We aimed to compare the association of different ID criteria with all-cause mortality after MI.

METHODS

Consecutive patients hospitalized for their first MI at a large tertiary heart center were included. We evaluated the association of different iron metabolism parameters measured on the first day after hospital admission with all-cause mortality.

RESULTS

From the 1,156 patients included (aged 64±12 years, 25 % women), 194 (16.8 %) patients died during the median follow-up of 3.4 years. After multivariate adjustment, iron level ≤13 µmol/L (HR 1.67, 95 % CI 1.19-2.34) and the combination of iron level ≤12.8 µmol/L and soluble transferrin receptor (sTfR) ≥3 mg/L (HR 2.56, 95 % CI 1.64-3.99) termed as PragueID criteria were associated with increased mortality risk and had additional predictive value to the GRACE score. Compared to the model including iron level, the addition of sTfR improved risk stratification (net reclassification improvement 0.61, 95 % CI 0.52-0.69) by reclassifying patients into a higher-risk group. No association between ferritin level and mortality was found. 51 % of patients had low iron levels, and 58 % fulfilled the PragueID criteria.

CONCLUSION

Iron deficiency is common among patients with the first MI. The PragueID criteria based on iron and soluble transferrin receptor levels provide the best prediction of mortality and should be evaluated in future interventional studies for the identification of patients potentially benefiting from intravenous iron therapy.

Remote Heart Failure Symptoms Assessment After Myocardial Infarction Identifies Patients at Risk for Death

BACKGROUND

Heart failure is a common complication after myocardial infarction (MI) and is associated with increased mortality. Whether remote heart failure symptoms assessment after MI can improve risk stratification is unknown. The authors evaluated the association of the 23-item Kansas City Cardiomyopathy Questionnaire (KCCQ) with all-cause mortality after MI.

METHODS AND RESULTS

Prospectively collected data from consecutive patients hospitalized for MI at a large tertiary heart center between June 2017 and September 2022 were used. Patients remotely completed the KCCQ 1 month after discharge. A total of 1135 (aged 64±12 years, 26.7% women) of 1721 eligible patients completed the KCCQ. Ranges of KCCQ scores revealed that 30 (2.6%), 114 (10.0%), 274 (24.1%), and 717 (63.2%) had scores <25, 25 to 49, 50 to 74, and ≥75, respectively. During a mean follow-up of 46 months (interquartile range, 29-61), 146 (12.9%) died. In a fully adjusted analysis, KCCQ scores <50 were independently associated with mortality (hazard ratio [HR], 6.05 for KCCQ <25, HR, 2.66 for KCCQ 25-49 versus KCCQ ≥50; both P<0.001). Adding the 30-day KCCQ to clinical risk factors improved risk stratification: change in area under the curve of 2.6 (95% CI, 0.3-5.0), Brier score of -0.6 (95% CI, -1.0 to -0.2), and net reclassification improvement of 0.71 (95% CI, 0.45-1.04). KCCQ items most strongly associated with mortality were walking impairment, leg swelling, and change in symptoms.

CONCLUSIONS

Remote evaluation of heart failure symptoms using the KCCQ among patients recently discharged for MI identifies patients at risk for mortality. Whether closer follow-up and targeted therapy can reduce mortality in high-risk patients warrants further study.