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

Implementation of new echocardiographic modalities in routine practice in a general hospital – Pocket-size cardiac ultrasound and 3 dimensional echocardiography. Studies on feasibility and diagnostic accuracy

This thesis is based upon the implementation of pocket-size cardiac ultrasound (PCU) among medical students and residents in internal medicine and 3 dimensional echocardiography (3DE) in routine care at a general hospital. The introduction of widely available and handy ultrasound devices has represented a challenge to the medical community as implementation in clinical practice can be made by non-specialists. In view of favorable results from the non-expert use of the larger laptop-sized devices, the thesis at hand aimed at evaluating the feasibility and diagnostic accuracy of PCU. Twenty one medical students and 26 internal medicine residents performed PCU at Oslo University Hospital, Rikshospitalet and Vestfold Hospital Trust respectively. After a brief 4 hour training with a Vscan device the medical students could detect mitral regurgitation significantly better than with a physical examination alone. Left ventricular (LV) dysfunction was detected with high sensitivity, whereas detection of aortic regurgitation and aortic stenosis did not improve. PCU was used infrequently used by the 26 medical residents after only 2 hours of training, and with an overall low sensitivity to detect disease. In view of a high specificity and negative predictive value, the PCU method, however, could provide a suitable means of ruling out significant disease. 3DE, the more advanced contemporary echocardiographic technique available, is at present more relevant than before due to faster acquisition and imaging. Thus, it has the potential to replace traditional 2 dimensional echocardiography (2DE) in cardiology care. To explore this, we performed a systematic literature search of studies comparing transthoracic 3DE with a standard 2DE in the evaluation of valvular heart disease and LV function. We found that 3DE was to be recommended rather than 2DE in usual patient care in order to evaluate cardiac LV volumes and ejection fraction (EF). These two parameters are considered to be essential in the therapeutic and prognostic assessment of several cardiac disorders. 3DE does, however, require better image quality and regular heart rhythm in the assessment of cardiac disease, and the search we performed did not adequately answer how many could not be examined with the 3DE technique. To that end, we designed a study of consecutive patients who had been through successful LV assessment by PCU, 2DE and 3DE. Of 273 patients successfully examined with PCU and 2DE, only 202 (74%) had satisfactory 3DE images. Contrary to many other studies in this field, a significant overestimation of LV volumes was observed in 2DE compared to 3DE, whereas no such difference was found for LV EF. We conclude that 2DE is still an important tool for LV studies and that it is essential to introduce concise recommendations for endocardial tracing of the LV cavity for both 2DE and 3DE echocardiography

Prevalence and prognosis of non-specific chest pain among patients hospitalized for suspected acute coronary syndrome - a systematic literature search

BACKGROUND: The term non-specific chest pain (NSCP) is applied to hospitalized patients in order to designate that they neither have an acute coronary syndrome (ACS) nor display evidence of a coronary ischemia. The number of NSCP patients is increasing and comprehensive guidelines specifying their optimal management have not yet been introduced. The objective of this review was to explore the prevalence and prognosis of NSCP versus ACS among patients recruited in consecutive series hospitalized for chest pain suspected to be ACS. METHODS: This is a systematic literature search where three databases were searched from 1990 to 14 November 2011. In addition, one database was searched for Epub ahead of print per 24 March 2012. Three inclusion criteria were applied: 1. documentation of an unselected consecutive series of patients admitted for chest pain, where this review is based upon two groups of patients defined as follows: a) 'ACS/high-risk' and b) NSCP; 2. at least 100 cases with NSCP; and 3. follow-up of hospital readmissions and mortality for at least six months. RESULTS: A total of 2,204 citations were screened after removal of duplicates. Out of 80 full text articles assessed for eligibility 12 studies were included, comprising 24,829 patients (inter-study range 250 to 13,762), with 11,008 (44%) categorized as NSCP and 13,821 (56%) as 'ACS/high-risk'. The mean one-year total mortality rate among patients with NSCP in nine studies was 3.2% (inter-study range 1.4% to 8.1%), with the highest mortality among patients with pre-existing coronary heart disease (CHD). The mean one-year mortality rate among 'ACS/high-risk' patients was 18.0% (inter-study range 14.0% to 19.9%) in four studies with available data. In six studies the mean one-year readmission rate for patients with NSCP was 17.5% (inter-study range 2.5% to 40%). CONCLUSIONS: Patients with NSCP represent a large, heterogeneous and important group. Due to co-existing CHD in nearly 40% of these patients, their prognosis is not necessarily benign. Although their average one-year mortality rate was almost six times lower than those with 'ACS/high-risk', the subset with concomitant CHD had a relatively poor prognosis when compared with NSCP patients without evidence of CHD

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 avoide

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

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

Effect of Oral β-blocker Treatment on Mortality in Contemporary Post-myocardial Infarction Patients: a systematic review and meta-analysis

Aims: Guidelines concerning β-blocker treatment following acute myocardial infarction (AMI) are based on studies undertaken before the implementation of reperfusion and secondary prevention therapies. We aimed to estimate the effect of oral β-blockers on mortality in contemporary post-AMI patients with low prevalence of heart failure and/or reduced left ventricular ejection fraction. Methods and results: A random effects model was used to synthetize results of 16 observational studies published between 1 January 2000 and 30 October 2017. Publication bias was evaluated, and heterogeneity between studies examined by subgroup and random effects meta-regression analyses considering patient-related and study-level variables. The pooled estimate showed that β-blocker treatment [among 164 408 (86.8%) patients, with median follow-up time of 2.7 years] was associated with a 26% reduction in all-cause mortality [rate ratio (RR) 0.74, 95% confidence interval (CI) 0.64–0.85] with moderate heterogeneity (I2 = 67.4%). The patient-level variable mean age of the cohort explained 31.5% of between study heterogeneity. There was presence of publication bias, or small study effect, and when controlling for bias by the trim and fill simulation method, the effect disappeared (adjusted RR 0.90, 95% CI 0.77–1.04). Also, small study effect was demonstrated by a cumulative meta-analysis starting with the largest study showing no effect, with increasing effect as the smaller studies were accumulated. Conclusion: Evidence from this study suggests that there is no association between β-blockers and all-cause mortality. A possible beneficial effect in AMI survivors needs to be tested by large randomized clinical trials