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.

Prognostic impact of non-improvement of global longitudinal strain in patients with revascularized acute myocardial infarction.

Global longitudinal strain (GLS) is a more sensitive prognostic factor than left ventricular ejection fraction (LVEF) in various cardiac diseases. Little is known about the clinical impact of GLS changes after acute myocardial infarction (AMI). The present study aimed to explore if non-improvement of GLS after 3 months was associated with higher risk of subsequent composite cardiovascular events (CCVE). Patients with AMI were consecutively included at a secondary care center in Norway between April 2016 and July 2018 within 4 days following percutaneous coronary intervention. Echocardiography was performed at baseline and after 3 months. Patients were categorized with non-improvement (0 to - 100%) or improvement (0 to 100%) in GLS relative to the baseline value. Among 214 patients with mean age 65 (± 10) years and mean LVEF 50% (± 8) at baseline, 50 (23%) had non-improvement (GLS: - 16.0% (± 3.7) to - 14.2% (± 3.6)) and 164 (77%) had improvement (GLS: - 14.0% (± 3.0) to - 16.9% (± 3.0%)). During a mean follow-up of 3.3 years (95% CI 3.2 to 3.4) 77 CCVE occurred in 52 patients. In adjusted Cox regression analyses, baseline GLS was associated with all recurrent CCVE (HR 1.1, 95% CI 1.0 to 1.2, p < 0.001) whereas non-improvement versus improvement over 3 months follow-up was not. Baseline GLS was significantly associated with the number of CCVE in revascularized AMI patients whereas non-improvement of GLS after 3 months was not. Further large-scale studies are needed before repeated GLS measurements may be recommended in clinical practice.Trial registration: Current Research information system in Norway (CRISTIN). Id: 506563.

Three-dimensional versus two-dimensional transthoracic echocardiography for left ventricular outflow tract measurements in severe aortic stenosis. A cross-sectional study using computer tomography and Haegar sizers as reference.

Objectives. In grading of aortic stenosis, two-dimensional transthoracic echocardiography (2D TTE) routinely results in underestimation of the left ventricular outflow tract (LVOT) area, and hence the aortic valve area (AVA). We investigated whether three-dimensional (3D) TTE measurements of the LVOT would be more accurate. We evaluated the feasibility, agreement and inter-observer variability of 3D TTE LVOT measurements with computed tomography (CT) and Haegar sizers as reference. Design. Sixty-one patients with severe aortic stenosis were examined with 2D and 3D TTE. 41 had CT and 13 also had perioperative Haegar sizing. Pearson's correlation and Bland-Altman plots were used to compare methods. Inter-observer variability was tested for 2D and 3D TTE. Trial registration: Current research information system in Norway (CRISTIN). Id: 555249. Results. Feasibility was 67% with 3D TTE and 100% with 2D TTE and CT. Mean LVOT area for 2D, 3D, CT and Haegar sizers were 3.7 ± 0.6 cm2, 4.0 ± 0.9 cm2, 5.2 ± 0.8 cm2 and 4.4 ± 1.0 cm2 respectively. Bias and limits of agreements for 2D TTE was 1.5 ± 1.3 cm2, compared with CT and 0.4 ± 1.5 cm2 with Haegar sizers. Corresponding results for 3D TTE were 1.2 ± 1.6 cm2 and 0.2 ± 1.8 cm2. Intraclass correlation coefficients for LVOT area were 0.62 for 3D and 0.86 for 2D. Conclusions. 2D TTE showed better feasibility and inter-observer variability in measurements of LVOT than 3D TTE. Both echocardiographic methods underestimated LVOT area compared to CT and Haegar sizers. These observations suggest that 2D TTE is still preferable to 3D TTE in the assessment of aortic stenosis.

The impact of semi-automatic versus manually adjusted assessment of global longitudinal strain in post-myocardial infarction patients.

There are unresolved questions related to the proper use of editing the region of interest (ROI) for measurements of global longitudinal strain (GLS). The purpose of the present study was to compare the semi-automatic default GLS value by the vendor's software with manually adjusted GLS and test the impact on GLS measures with different ROI widths. We selected 25 patients post myocardial infarction treated with PCI who had excellent echocardiographic recordings after 2-5 days and 3 months. The different GLS values were assessed from these 50 analyses in three steps. The semi-automatically GLS by default ROIs was compared with manually adjusted ROIs widths selected by an expert and then with manual adjustments, but with fixed ROIs being narrow, medium and wide. Their mean age was 64 (± 12) years, 52% had ST elevation MI and mean LVEF was 52 (± 4)%. Mean default GLS was - 15.3 (± 2.5)% with the widest ROI level selected semi-automatically in 78% of all widths. The mean expert GLS with manually adjusted ROI was - 14.7 (± 2.4)%, and the medium ROI level was selected by the expert in 85% of all examinations. The mean adjusted GLS, but with fixed ROIs widths was - 15.0 (± 2.5%)% with narrow ROI, - 14.7 (± 2.6)% with medium and - 13.5 (± 2.3)% with wide ROI width (p < 0.001 vs. default GLS). The Intra Class Coefficient Correlation between default and manually adjusted expert GLS was 0.93 (p < 0.001). The difference between the default and the manually adjusted expert GLS was neglectable. These findings may represent a simplification of the assessment of GLS that might increase its use in clinical practice. The GLS measurements with a fixed wide ROIs were significantly different from the expert measurements and indicate that a wide ROI should be avoided.

Focused cardiac ultrasound by unselected residents-the challenges.

BACKGROUND: Focus Cardiac Ultrasound (FoCUS) performed by internal medicine residents on call with 2 h of training can provide a means for ruling out cardiac disease, but with poor sensitivity. The purpose of the present study was to evaluate diagnostic usefulness as well as diagnostic accuracy of FoCUS following 4 h of training. METHODS: All residents on call were given a 4-h training course with an additional one-hour training course after 6 months. They were asked to provide a pre- and post-FoCUS diagnosis, with the final diagnosis at discharge as reference. RESULTS: During a 7 month period 113 FoCUS examinations were reported; after 53 were excluded this left 60 for evaluation with a standard echocardiogram performed on average 11.5 h after FoCUS. Examinations were performed on the basis of chest pain and dyspnoea/edema. The best sensitivity was found in terms of the detection of reduced left ventricular (LV) ejection fraction (EF) (92%), LV dilatation (85%) and pericardial effusion (100%). High values were noted for negative predictive values, although false positives were seen. A kappa > 0.6 was observed for reduced LVEF, right ventricular area fraction and dilatation of LV and left atrium. In 48% of patients pre- and post-FoCUS diagnoses were identical and concordant with the final diagnosis. Importantly, in 30% examinations FoCUS correctly changed the pre-FoCUS diagnosis. CONCLUSIONS: A FoCUS protocol with a 4-h training program gained clinical usefulness in one third of examinations. False positive findings represented the major challenge.

Diagnostic accuracy of left ventricular longitudinal function by speckle tracking echocardiography to predict significant coronary artery stenosis. A systematic review.

BACKGROUND: Patients evaluated for acute and chronic chest pain comprise a large, heterogeneous group that often provides diagnostic challenges. Although speckle tracking echocardiography (STE) has proved to have diagnostic value in acute coronary syndrome it is not commonly incorporated in everyday practice. The purpose of the present systematic review was to assess the diagnostic accuracy of left ventricular (LV) longitudinal function by STE to predict significant coronary artery stenosis (CAD+) or not (CAD-) verified by coronary angiography in patients with chest pain suspected to be of cardiac ischemic origin. METHODS: 4 electronic databases; Embase, Medline, Cochrane and PubMed ahead-of print were searched for per 19.05.14. Only full-sized articles including >40 patients were selected. RESULTS: A total of 166 citations were identified, 16 full-size articles were assessed of which 6 were found eligible for this review. Of 781 patients included 397 (60%) had CAD+. The overall weighted mean global longitudinal strain (GLS) was -17.2% (SD=2.6) among CAD+ vs. -19.2% (SD=2.8) in CAD- patients. Mean area under curve in 4 studies for predicting CAD+ ranged from 0.68 to 0.80. The study cut-off levels for prediction of CAD+ in the ROC analysis varied between -17.4% and -19.7% with sensitivity from 51% to 81% and specificity between 58% and 81%. In 1 study GLS obtained during dobutamine stress echocardiography (DSE) had the best accuracy. Regional strain measurements were not uniform, but may have potential in detecting CAD. CONCLUSIONS: GLS measurements at rest only have modest diagnostic accuracy in predicting CAD+ among patients presenting with acute or chronic chest pain. The results from regional strain, layer specific strain and DSE need to be verified in larger studies.