Novel regional longitudinal strain by speckle tracking to detect significant coronary artery disease in patients admitted to the emergency department for chest pain suggestive of acute coronary syndrome.

BACKGROUND

Global longitudinal strain has shown variable results in detecting ischemia in patients admitted to the emergency department with chest pain, but without other clear evidence of coronary artery disease (CAD). Our aim was to investigate whether assessment of regional longitudinal myocardial function could assist in detecting significant CAD in these patients.

METHODS

Clinical evaluation, electrocardiogram, echocardiogram and troponin T were evaluated in 126 patients admitted with chest pain. A subsequent invasive coronary angiography divided patients into two groups: significant CAD (CAD+) or non-significant CAD (CAD-). Global and regional myocardial function were evaluated by speckle tracking echocardiography. Regional longitudinal strain was defined as the highest longitudinal strain values in four adjacent left ventricular segments and termed 4AS.

RESULTS

CAD+ was found in 37 patients (29%) of which 51% had elevated troponin. Mean 4AS was - 13.1% (± 3.5) in the CAD+ and - 15.2% (± 2.7) (p = 0.002) in the CAD- group. Predictors for CAD+ were age [OR 1.06 (1.01-1.11, p = 0.026)], smoking [OR 3.39 (1.21-9.51, p = 0.020)], troponin [OR 3.32 (1.28-8.60, p = 0.014)) and 4AS (OR 1.24 (1.05-1.46, p = 0.010)]. A cutoff for 4AS of > - 15% showed the best diagnostic performance with event-reclassification of 0.41 (p < 0.001), non-event-reclassification of - 0.34 (p < 0.001) and net reclassification improvement 0.07 (p = 0.60).

CONCLUSION

Decreased myocardial function in four adjacent LV segments assessed by strain has the potential to detect significant CAD in patients admitted with chest pain and negative/slightly elevated initial troponin.

TRIAL REGISTRATION

Current Research information system in Norway (CRISTIN). Id: 555249.