Improved assessment of left ventricular volumes and ejection fraction by contrast enhanced harmonic color Doppler echocardiography

LVEF by Multigated Acquisition Scan Compared to Other Imaging Modalities in Cardio-Oncology: a Systematic Review

PURPOSE OF REVIEW

The prevalence of cancer therapy-related cardiac dysfunction (CTRCD) is increasing due to improved cancer survival. Serial monitoring of cardiac function is essential to detect CTRCD, guiding timely intervention strategies. Multigated radionuclide angiography (MUGA) has been the main screening tool using left ventricular ejection fraction (LVEF) to monitor cardiac dysfunction. However, transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (CMR) may be more suitable for serial assessment. We aimed to assess the concordance between different non-radiating imaging modalities with MUGA to determine whether they can be used interchangeably.

RECENT FINDINGS

In order to identify relevant studies, a PubMed search was performed. We included cross-sectional studies comparing MUGA LVEF to that of 2D TTE, 3D TTE, and CMR. From 470 articles, 22 were selected, comprising 1017 patients in total. Among others, this included three 3D TTE, seven 2D harmonic TTE + contrast (2DHC), and seven CMR comparisons. The correlations and Bland-Altman limits of agreement varied for CMR but were stronger for 3D TTE and 2DHC. Our findings suggest that MUGA and CMR should not be used interchangeably whereas 3D TTE and 2DHC are appropriate alternatives following an initial MUGA scan. We propose a multimodality diagnostic imaging strategy for LVEF monitoring in patients undergoing cancer treatment.

Short-lag spatial coherence imaging of cardiac ultrasound data: initial clinical results

Short-lag spatial coherence (SLSC) imaging is a novel beamforming technique that reduces acoustic clutter in ultrasound images. A clinical study was conducted to investigate clutter reduction and endocardial border detection in cardiac SLSC images. Individual channel echo data were acquired from the left ventricle of 14 volunteers, after informed consent and institutional review board approval. Paired B-mode and SLSC images were created from these data. Contrast, contrast-to-noise, and signal-to-noise ratios were measured in paired images, and these metrics were improved with SLSC imaging in most cases. Three cardiology fellows rated the visibility of endocardial segments in randomly ordered B-mode and SLSC cine loops. SLSC imaging offered 22%-33% improvement (p < 0.05) in endocardial border visibility when B-mode image quality was poor (i.e., 80% or more of the endocardial segments could not be visualized by the three reviewers). The percentage of volunteers with poor-quality images was decreased from 21% to 7% with the SLSC beamformer. Results suggest that SLSC imaging has the potential to improve clinical cardiac assessments that are challenged by clutter.

Results from an Australian and New Zealand audit of left ventricular ejection fraction from gated heart pool scan analysis

AIM

A voluntary audit was undertaken to compare left ventricular ejection fraction (LVEF) calculations from gated heart pool studies using software packages currently available throughout Australia and New Zealand (ANZ).

METHODS

A data set previously developed by a task group of the Institute of Physics and Engineering in Medicine (IPEM) consisting of 12 planar gated studies with LVEF ranging from 17 to 67% was provided to each site with worksheets to record individual technologist's results as well as information about individual department's equipment, software used for calculation of LVEF and experience of the analysers. Data analysis included calculation of an overall mean LVEF and standard deviation (SD) for all patients, which were compared with the mean IPEM LVEF. A comparison among software packages was done to examine differences in mean LVEF.

RESULTS

Results were received from a total of 22 sites using six different software packages, with 187 processed studies included for analysis. Reproducibility of studies 4 and 8 showed good agreement, with an SD of 1.0 EF units (P=0.5290). Good correlation was found between the ANZ mean LVEF and the corresponding IPEM value per patient study, with R=0.98. The ANZ overall mean LVEF was 47%, which was higher that the IPEM mean by 4.9 EF units. The average difference among all software packages was +5.1 EF units.

CONCLUSION

Differences were found between the IPEM mean and the ANZ mean LVEF. Variability in LVEF values between software packages was demonstrated, with an average of 5.1 EF units. The ANZ overall mean for LVEF was 47.2%, being 4.9 EF units higher than the IPEM value.

Importance of transesophageal echocardiography in the critically ill and injured patient

Echocardiography, particularly transesophageal echocardiography (TEE), is a vital diagnostic and monitoring imaging modality for the intensivist. The field of echocardiography spans different venues and pathologies, ranging from surface transthoracic echocardiography and portable hand-held echocardiography, to contrast echocardiography, stress echocardiography, and TEE, among others. Numerous investigations have proven the worth of echocardiography, especially TEE, in the critically ill and injured patient, changing lives with the identification of obvious and subtle cardiothoracic diseases. Because this powerful imaging tool is immediately available and portable, crucial delays in diagnosis are not commonplace; rather than echocardiography, TEE, specifically, should be (and is in some institutions) the standard of care and management in assisting the intensivist in diagnosis of a variety of maladies. The effect of TEE technology is quite formidable, and numerous investigations have borne this out. The therapeutic effect of TEE ranges from 10% to 69%, with the majority of investigations falling into the 60% to 65% range. The diagnostic yield of TEE is far greater, approaching 78%. This article will detail the importance of echocardiography, its efficacy, and its high-yield imaging capability, particularly when compared with other imaging modalities, even transthoracic echocardiography.