Variability in Reassessment of Left Ventricular Ejection Fraction After Myocardial Infarction in the Acute Myocardial
Stephen B Wilton1, Matthew T Bennett2, Ratika Parkash3
1Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
Insights
One-third of heart attack patients with reduced ejection fraction did not get follow-up imaging within 6 months. Persistent reduction in left ventricular ejection fraction (LVEF) was common, highlighting a gap in post-myocardial infarction care.
Area of Science:
- Cardiology
- Cardiovascular Medicine
- Clinical Research
Background:
- Persistently depressed left ventricular ejection fraction (LVEF) after myocardial infarction (MI) indicates poor prognosis and necessitates evidence-based treatments to prevent sudden cardiac death and heart failure.
- Guideline-recommended LVEF reassessment is crucial for guiding post-MI management.
Purpose of the Study:
- To evaluate adherence to recommended LVEF reassessment protocols within six months following acute myocardial infarction (MI).
- To analyze the changes in LVEF over a six-month follow-up period in patients post-MI.
Main Methods:
- A multicenter cohort study involving 501 patients with acute MI and LVEF ≤ 45% across Canadian hospitals.
- Patients were followed for six months, with data collected on baseline characteristics, in-hospital care, and LVEF.
- Outcomes included repeat LVEF assessment by six months and identification of persistent LVEF reduction at thresholds of ≤40% or ≤35%.
Main Results:
- Only 66.2% of patients underwent LVEF reassessment within six months.
- Patients from community hospitals and those with lower baseline LVEF were more likely to have reassessment.
- Over one-third of patients (34.1%) exhibited a clinically relevant persistent LVEF reduction, with 17.2% having LVEF ≤ 35%.
Conclusions:
- A significant proportion of patients (approximately one-third) with reduced LVEF post-MI did not receive timely reassessment as per guidelines.
- Persistent LVEF reduction was identified in over one-third of patients who underwent follow-up imaging.
- Quality improvement initiatives are needed to ensure timely cardiac imaging and optimal management for post-MI patients with reduced LVEF.
Importance:
Persistently depressed left ventricular ejection fraction (LVEF) after myocardial infarction (MI) is associated with adverse prognosis and directs the use of evidence-based treatments to prevent sudden cardiac death and/or progressive heart failure.
Objective:
To assess adherence with guideline-recommended LVEF reassessment and to study the evolution of LVEF over 6 months of follow-up.
Design, Setting, And Participants:
This was a multicenter cohort study at Canadian academic and community hospitals with on-site cardiac catheterization services. Patients with type 1 acute MI and LVEF less than or equal to 45% during the index hospitalization were enrolled between January 2018 and August 2019 and were followed-up for 6 months. Data analysis was performed from May 2020 to September 2021.
Exposures:
Baseline clinical factors, in-hospital care and LVEF, and site-specific features.
Main Outcomes And Measures:
The main outcomes were receipt of repeat LVEF assessment by 6 months and the presence of a persistent LVEF reduction at 2 thresholds: LVEF less than or equal to 40%, prompting consideration of additional medical therapy for heart failure, or LVEF less than or equal to 35%, prompting referral for implanted cardioverter defibrillator in addition to medical therapy.
Results:
This study included 501 patients (mean [SD] age, 63.3 [13.0] years; 113 women [22.6%]). Overall, 370 patients (73.4%) presented with STEMI, and 454 (90.6%) had in-hospital revascularization. The median (IQR) baseline LVEF was 40% (34%-43%). Of 458 patients (91.4%) who completed the 6-month follow-up, 303 (66.2%; 95% CI, 61.7%-70.5%) had LVEF reassessment, with a range of 46.7% to 90.0% across sites (χ213 = 19.6; P = .11). Participants from community hospitals were more likely than those from academic hospitals to undergo LVEF reassessment (73.6% vs 63.2%; χ21 = 4.50; P = .03), as were those with worse LVEF at baseline. Follow-up LVEF improved by an absolute median (IQR) of 8% (3%-15%). However, 103 patients (34.1%) met the definitions of clinically relevant LVEF reduction, including 52 patients (17.2%) with LVEF less than or equal to 35% and 51 patients (16.9%) with LVEF of 35.1% to 40.0%.
Conclusions And Relevance:
In this cohort study, approximately 1 in 3 patients with at least mild LVEF reduction after acute MI did not undergo indicated LVEF reassessment within 6 months, suggesting that programs to improve the quality of post-MI care should include measures to ensure that indicated repeat cardiac imaging is performed. In those with follow-up imaging, clinically relevant persistent LVEF reduction was identified in more than one-third of patients.
