Abstract

Prior myocardial infarction (MI) is associated with increased mortality and is prevalent in certain high risk patient groups. Electrocardiogram may be used in diagnosis, however, sensitivity is limited, thus non-invasive imaging techniques may improve diagnosis. We investigated whether global longitudinal strain (GLS) and longitudinal strain parameters are reduced in patients with prior MI but preserved left ventricular ejection fraction (LVEF). The study included 40 clinical patients with prior MI occurring >3 months previously (defined as subendocardial hyperenhancement on late Gadolinium enhancement imaging) with LVEF ≥ 55% and 40 controls matched for age and LVEF. GLS, global longitudinal strain rate (GLSR) and early diastolic longitudinal strain rate (GLSRe) were measured from cine imaging feature tracking analysis. Presence of wall motion abnormality (WMA) and minimum systolic wall thickening (SWT) were calculated from cine imaging. GLS was −17.3 ± 3.7% in prior MI versus −19.3 ± 1.9% in controls (p = 0.012). GLSR was −88.0 ± 33.7%/s in prior MI versus −103.3 ± 26.5%/s in controls (p = 0.005). GLSRe was 76.4 ± 28.4%/s in prior MI versus 95.5 ± 26.0%/s in controls (p = 0.001). GLS accurately identified prior MI [AUC 0.662 (95% CI 0.54–0.785) p = 0.012] whereas WMA [AUC 0.500 (95% CI 0.386–0.614) p = 1.0] and minimum SWT [AUC 0.609 (95% CI 0.483–0.735) p = 0.093] did not. GLS, GLSR and GLSRe are reduced in prior MI with preserved LVEF. Normal LVEF and lack of WMA cannot exclude prior MI. Prior MI should be considered when reduced GLS, GLSR or GLSRe are detected by non-invasive imaging.

Highlights

  • Prior myocardial infarction (MI) is defined as either the presence of pathological Q waves on an electrocardiogram (ECG), regional loss of myocardium on cardiovascular (CV) imaging in the absence of a non-ischemic cause or pathological findings supportive of prior MI [1]

  • This was a single centre case control study involving 40 clinical patients with prior MI occurring >3 months previously and preserved left ventricular ejection fraction (LVEF) (≥55%) and 40 controls matched for age and sex with LVEF (≥55%)

  • Impairment of global longitudinal strain rate (GLSR) and GLSRe had superior diagnostic accuracy than the quantitative assessment of wall motion abnormality (WMA) in the detection of prior MI. These results demonstrate that prior MI may be detected when global longitudinal strain (GLS) is impaired when LVEF is preserved, its ability to detect prior MI in this context is moderate

Read more

Summary

Introduction

Prior myocardial infarction (MI) is defined as either the presence of pathological Q waves on an electrocardiogram (ECG), regional loss of myocardium on cardiovascular (CV) imaging in the absence of a non-ischemic cause or pathological findings supportive of prior MI [1]. Myocardial infarction is frequently unrecognized at the time of its occurrence, accounting for 20–40% of all prior MI in high risk populations diagnosed on ECG criteria [2, 3]. Cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) imaging offers a more sensitive means of diagnosis than ECG and is considered the reference standard non-invasive imaging technique for the detection of prior MI [4, 5]. Studies using this approach have suggested that unrecognized MI is more common than recognized prior MI in certain populations, with a prevalence of 18% in an elderly, community-based cohort [6]. Recognition of the condition is important and secondary prevention therapy aimed at reducing long-term CV risk is recommended when prior MI is diagnosed [8]

Methods
Results
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call