Left ventricular remodelling and systolic function measurement with 64 multi-slice computed tomography versus second harmonic echocardiography in patients with coronary artery disease: A double blind study

Cardiac Computed Tomography: Application in Valvular Heart Disease

The incidence and prevalence of valvular heart disease (VHD) is increasing and has been described as the next cardiac epidemic. Advances in imaging and therapeutics have revolutionized how we assess and treat patients with VHD. Although echocardiography continues to be the first-line imaging modality to assess the severity and the effects of VHD, advances in cardiac computed tomography (CT) now provide novel insights into VHD. Transcatheter valvular interventions rely heavily on CT guidance for procedural planning, predicting and detecting complications, and monitoring prosthesis. This review focuses on the current role and future prospects of CT in the assessment of aortic and mitral valves for transcatheter interventions, prosthetic valve complications such as thrombosis and endocarditis, and assessment of the myocardium.

Simultaneous Assessment of Left Ventricular Function and Coronary Artery Anatomy by Third-generation Dual-source Computed Tomography Using a Low Radiation Dose

BACKGROUND

To assess left ventricular function and coronary artery simultaneously by third-generation dual-source computed tomography (CT) using a low radiation dose.

METHODS

A total of 48 patients (36 men, 12 women; mean age 57.0 ± 9.5 years) who underwent both electrocardiography-gated cardiac CT angiography (CCTA) using 70–90 kVp and echocardiography were included in this retrospective study. The correlation between left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and left ventricular ejection fraction (LVEF) measured using CCTA and echocardiography was determined. The quality of coronary artery images was analyzed using a 4-point scale (1, excellent; 4, poor). The effective radiation dose of CCTA was calculated.

RESULTS

Mean heart rate during the CT examination was 59.9 ± 9.9 bpm (range 38–79) and the body mass index of 48 patients was 24.5 ± 2.6 kg/m² (range 17.0–29.4). LVEDV, LVESV, and LVEF measured using CCTA and echocardiography demonstrated a fair to moderate correlation (Pearson correlation coefficient: r = 0.395, p = 0.005 for LVEDV; r = 0.509. p < 0.001 for LVESV; r = 0.551, p < 0.001 for LVEF). Average image quality score of coronary arteries was 1.0 ± 0.1 (range 1–2). A total of 99.0% (783 of 791) of segments had an excellent image quality score, and 1.0% (8 of 791) of segments had a good score. Mean effective radiation dose was 2.2 ± 0.7 mSv.

CONCLUSIONS

Third-generation dual-source CT using a low tube voltage simultaneously provides information regarding LV function and coronary artery disease at a low radiation dose. It can serve as an alternative option for functional assessment, particularly when other imaging modalities are inadequate.

Cardiac Computed Tomography - More Than Coronary Arteries? A Clinical Update

BACKGROUND

 Rapid improvement of scanner and postprocessing technology as well as the introduction of minimally invasive procedures requiring preoperative imaging have led to the broad utilization of cardiac computed tomography (CT) beyond coronary CT angiography (CTA).

METHOD

 This review article presents an overview of recent literature on cardiac CT. The goal is to summarize the current guidelines on performing cardiac CT and to list established as well as emerging techniques with a special focus on extracoronary applications.

RESULTS AND CONCLUSION

 Most recent guidelines for the appropriate use of cardiac CT include the evaluation of coronary artery disease, cardiac morphology, intra- and extracardiac structures, and functional and structural assessment of the myocardium under certain conditions. Besides coronary CTA, novel applications such as the calculation of a CT-derived fractional flow reserve (CT-FFR), assessment of myocardial function and perfusion imaging, as well as pre-interventional planning in valvular heart disease or prior pulmonary vein ablation in atrial fibrillation are becoming increasingly important. Especially these extracoronary applications are of growing interest in the field of cardiac CT and are expected to be gradually implemented in the daily clinical routine.

KEY POINTS

  · Coronary artery imaging remains the main indication for cardiac CT. · Novel computational fluid dynamics allow the calculation of a CT-derived fractional flow reserve in patients with known or suspected coronary artery disease. · Cardiac CT delivers information on left ventricular volume as well as myocardial function and perfusion. · CT is the cardinal element for pre-interventional planning in transcatheter valve implantation and pulmonary vein isolation.

CITATION FORMAT

· Taron J, Foldyna B, Eslami P et al. Cardiac Computed Tomography - More Than Coronary Arteries? A Clinical Update. Fortschr Röntgenstr 2019; 191: 817 - 826.

Quantitative Assessment of Left Ventricular Function and Myocardial Mass: A Comparison of Coronary CT Angiography with Cardiac MRI and Echocardiography

Background

The purpose of this study was to compare the left ventricular parameters obtained from multi-detector row computed tomography (MDCT) studies with two-dimensional echocardiography (2DE), and magnetic resonance imaging (MRI), which is accepted as the gold standard in the evaluation of left ventricular functions. The study also aimed to evaluate whether or not there is a relationship between the MR-Argus and CMR tools software programs which are used in post-process calculations of data obtained by MRI.

Material/Methods

Forty patients with an average age of 51.4±14.9 years who had been scanned with cardiac MDCT were evaluated with cardiac MRI and 2DE. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), cardiac output (CO), and myocardial mass values calculated by MDCT, MRI, and 2DE were compared with each other. Two different MR software programs were used to compare left ventricular functions. The CMR tools LV tutorials method is accepted as the gold standard because it can be used in three-dimensional functional evaluation. The Pearson Correlation and Bland-Altman analysis were performed to compare the results from the two MR methods (MR-Argus and CMR tools) and the results from both the MDCT and the 2DE with the CMR tools results.

Results

Strong positive correlations for EF values were found between the MDCT and CMR tools (r=0.702 p<0.001), and between the MR-Argus and CMR tools (r=0.746 p<0.001). The correlation between the 2DE and CMR tools (r=0.449 p<0.004), however, was only moderate. Similar results were obtained for the other parameters. The strongest correlation for ESV, EDV, and EF was between the two MR software programs. The correlation coefficient between the MDCT and CMR tools is close to the correlation coefficient between the two software programs. While the correlation between 2DE and CMR tools was satisfactory for ESV, EDV, and CO values, it was at a moderate level for the other parameters.

Conclusions

Left ventricular functional analysis can be performed easily and reliably with cardiac MDCT used for coronary artery evaluation and it also gives more accurate results than 2DE.

Analysis of ventricular function by CT

The assessment of ventricular function, cardiac chamber dimensions, and ventricular mass is fundamental for clinical diagnosis, risk assessment, therapeutic decisions, and prognosis in patients with cardiac disease. Although cardiac CT is a noninvasive imaging technique often used for the assessment of coronary artery disease, it can also be used to obtain important data about left and right ventricular function and morphology. In this review, we will discuss the clinical indications for the use of cardiac CT for ventricular analysis, review the evidence on the assessment of ventricular function compared with existing imaging modalities such cardiac magnetic resonance imaging and echocardiography, provide a typical cardiac CT protocol for image acquisition and postprocessing for ventricular analysis, and provide step-by-step instructions to acquire multiplanar cardiac views for ventricular assessment from the standard axial, coronal, and sagittal planes. Furthermore, both qualitative and quantitative assessments of ventricular function as well as sample reporting are detailed.

Accuracy of multi-slice computed tomography for measurement of left ventricular ejection fraction compared with cardiac magnetic resonance imaging and two-dimensional transthoracic echocardiography: a systematic review and meta-analysis

BACKGROUND

Multi-slice computed tomography (MSCT) allows non-invasive assessment of the coronary arteries and simultaneously can provide measurement of left ventricular ejection fraction (LVEF). The accuracy of newer MSCT generations (64-slice or more) for assessment of LVEF compared with magnetic resonance imaging (MRI) and two-dimensional transthoracic echocardiography (TTE) has not been evaluated in a meta-analysis.

PURPOSE

To evaluate, via a systematic literature review and meta-analysis, whether MSCT can assess LVEF with high accuracy compared with MRI and TTE.

METHODS

Electronic databases and reference lists for relevant published studies were searched. Twenty-seven eligible studies provided mean LVEF% with its standard deviation (SD) measured by MSCT versus MRI and TTE. Meta-analysis of weighted mean difference (WMD) and Bland-Altman method were used to quantify the mean difference and agreement between MSCT compared with MRI and TTE.

RESULTS

The results of combining 12 studies showed no significant difference in LVEF% between MSCT and MRI with a WMD of -0.11 (-1.48, 1.26, 95% CI), p=0.88. Bland-Altman analysis showed excellent agreement between MSCT and MRI with a bias of 0.0 (-3.7, 3.7 ± 1.96SD) with 95% CI. The results of combining 15 studies showed no significant difference in LVEF between MSCT versus TTE measurements with a WMD of 0.19 (-1.13 to 1.50; 95% CI), p=0.87. Bland-Altman analysis showed excellent agreement between MSCT and TTE with a bias of 0.3 (-4.7, 5.7 ± 1.96SD) with 95% CI.

CONCLUSION

The newer MSCT generations can provide accurate LVEF measurement compared to MRI and TTE. MSCT represents a valid technique for the combined evaluation of LVEF and coronary artery disease.

Percutaneous Treatment of Primary and Secondary Mitral Regurgitation: Overall Scope of the Problem

Mitral regurgitation is a heterogeneous disorder requiring the understanding of complex mitral anatomy and pathophysiology. Advanced imaging has furthered our knowledge and ability to treat patients with this disorder. As the demand for less invasive treatment increases, a multitude of percutaneous options have emerged. This review is written for interventionalists to fully appreciate the overall scope of the problem of mitral regurgitation. Understanding and integrating mitral anatomy with pathophysiology, multimodality imaging, and current transcatheter mitral therapies are paramount for treating this disorder.

Role of computed tomography imaging for transcatheter valvular repair/insertion

During the last decade, the development of transcatheter based therapies has provided feasible therapeutic options for patients with symptomatic severe valvular heart disease who are deemed inoperable. The promising results of many nonrandomized series and recent landmark trials have increased the number of percutaneous transcatheter valve procedures in high operative risk patients. Pre-procedural imaging of the anatomy of the aortic or mitral valve and their spatial relationships is crucial to select the most appropriate device or prosthesis and to plan the percutaneous procedure. Multidetector row computed tomography provides 3-dimensional volumetric data sets allowing unlimited plane reconstructions and plays an important role in pre-procedural screening and procedural planning. This review will describe the evolving role of multidetector row computed tomography in patient selection and strategy planning of transcatheter aortic and mitral valve procedures.

Screening and construction of Saccharomyces cerevisiae strains with improved multi-tolerance and bioethanol fermentation performance

In this study, a systemic analysis was initially performed to investigate the relationship between fermentation-related stress tolerances and ethanol yield. Based on the results obtained, two elite Saccharomyces cerevisiae strains, Z8 and Z15, with variant phenotypes were chosen to construct strains with improved multi-stress tolerance by genome shuffling in combination with optimized initial selection. After three rounds of genome shuffling, a shuffled strain, YZ1, which surpasses its parent strains in osmotic, heat, and acid tolerances, was obtained. Ethanol yields of YZ1 were 3.11%, 10.31%, and 10.55% higher than those of its parent strains under regular, increased heat, and high gravity fermentation conditions, respectively. YZ1 was applied to bioethanol production at an industrial scale. Results demonstrated that the variant phenotypes from available yeast strains could be used as parent stock for yeast breeding and that the genome shuffling approach is sufficiently powerful in combining suitable phenotypes in a single strain.