Influence of Reader Expertise on Myocardial Infarction Detection: A Comparative Study of Dark-Blood and Bright-Blood Late Gadolinium Enhancement MRI.

Abstract

Objectives: This study aimed to evaluate the influence of reader training and experience on the detection of (small) myocardial infarctions (MIs) and the assessment of ischemic scar transmurality using dark-blood late gadolinium enhancement (LGE) and bright-blood LGE magnetic resonance imaging. It was hypothesized that dark-blood LGE simplifies the detection of (small) MIs for less experienced readers, compared with bright-blood LGE imaging.

Materials and methods: One hundred patients referred for cardiac magnetic resonance imaging for suspected ischemic scar were retrospectively included. Dark-blood LGE was performed first, followed by bright-blood LGE. Nine clinicians, grouped into three levels based on their training and experience, assessed the LGE images for the presence of MI and ischemic scar transmurality. Their assessment was subsequently compared with a European Association of Cardiovascular Imaging level 3 consultant. Reader confidence was evaluated with a 4-point Likert scale. Multilevel logistic regression was used to compare the 2 LGE methods and assess differences in myocardial infarction detection and transmurality among the 3 experience levels. Wilcoxon signed rank tests were performed to compare the reader confidence between the 2 LGE methods, whereas Friedman omnibus tests were conducted to assess differences in reader confidence among the 3 experience levels.

Results: Dark-blood LGE resulted in increased correct detection of MIs compared with bright-blood LGE for both level 1 (87.3% vs 82.7%, odds ratio [OR]: 1.55 [95% confidence interval (CI): 0.94-2.54], P  = 0.083) and level 2 readers (89.7% vs 83.0%, OR: 2.05 [95% CI: 1.20-3.51], P  = 0.009). There was no significant difference observed between dark-blood LGE and bright-blood LGE for level 3 readers (88.7% vs 87.0%, OR: 1.20 [95% CI: 0.70-2.06], P  = 0.495). Level 2 readers significantly detected more small MIs correctly when using dark-blood LGE compared with bright-blood LGE (66.7% vs 50.8%, OR: 2.40 [95% CI: 1.03-5.60], P  = 0.042). All experience levels showed significantly increased confidence in presence of ischemic scar and transmurality with dark-blood LGE.

Conclusions: Readily available dark-blood LGE can assist less experienced readers in correctly detecting and assessing (small) MIs compared with conventional bright-blood LGE. Regardless of experience level, dark-blood LGE improves reader confidence in assessing the presence and transmurality of MIs.