Cardiac Computed Tomography

Purpose Metallic artifacts can result in an artificial thickening of the coronary stent wall which can significantly impair computed tomography (CT) imaging in patients with coronary stents. The objective of this study is to assess in vivo visualization of coronary stent wall and lumen with an edge-enhancing CT reconstruction kernel, as compared to a standard kernel. Methods This is a prospective cross-sectional study involving the assessment of 71 coronary stents (24 patients), with blinded observers. After 256-slice CT angiography, image reconstruction was done with medium-smooth and edge-enhancing kernels. Stent wall thickness was measured with both orthogonal and circumference methods, averaging thickness from diameter and circumference measurements, respectively. Image quality was assessed quantitatively using objective parameters (noise, signal to noise (SNR) and contrast to noise (CNR) ratios), as well as visually using a 5-point Likert scale. Results Stent wall thickness was decreased with the edge-enhancing kernel in comparison to the standard kernel, either with the orthogonal (0.97 ± 0.02 versus 1.09 ± 0.03 mm, respectively; p<0.001) or the circumference method (1.13 ± 0.02 versus 1.21 ± 0.02 mm, respectively; p = 0.001). The edge-enhancing kernel generated less overestimation from nominal thickness compared to the standard kernel, both with the orthogonal (0.89 ± 0.19 versus 1.00 ± 0.26 mm, respectively; p<0.001) and the circumference (1.06 ± 0.26 versus 1.13 ± 0.31

We present a large single-center series (&gt;2200 cases) operated for Tetralogy of Fallot (TOF). We analyzed the incidence of associated unusual and uncommonly described cardiac lesions and their diagnostic and therapeutic implications in TOF patients. This retrospective study was conducted by reviewing records of patients operated for TOF at a large tertiary care pediatric cardiac centre. From 2002 to 2008, a total of 2235 cases of TOF were evaluated with echocardiography, cardiac catheterization, and/or cardiac computed tomography followed by cardiac surgery. Known and well-described associations were excluded from the study. Unusual associations were tabulated. Several unusual associations having an incidence &gt;0.1% were detected. These included subaortic membrane (1%), pulmonary venous abnormalities (0.5%), small left ventricle (0.5%), interrupted inferior vena cava (0.5%), mitral valve abnormalities (0.4%), hemitruncus (0.4%), tricuspid valve abnormalities (0.4%), biventricul...

Subjects aged over 65 years without symptomatic chest pain were recruited for the KLoSHA in 2006 by random stratified sampling (439 men and 561 women). Anthropometrics, biochemical parameters, body composition, and abdominal fat by computed tomography (CT) were ...

Multidetector computed tomography (MDCT) using 64 detectors is widely used for cardiac imaging in the clinical setting. Despite promising results, 64-slice MDCT has important limitations for cardiac applications related to detector coverage, which leads to longer scan times, image artifacts, increased radiation and the need for higher contrast doses. The advent of wide or full cardiac coverage with 256- or

Background This study evaluates whether non-contrast cardiac computed tomography (CCT) can detect chronic myocardial infarction (MI) in patients with irreversible perfusion defects on nuclear myocardial perfusion imaging (MPI). Methods One hundred twenty-two symptomatic patients with irreversible perfusion defect (N = 62) or normal MPI (N = 60) underwent coronary artery calcium (CAC) scanning. MI on these non-contrast CCTs was visually detected based on the hypo-attenuation areas (dark) in the myocardium and corresponding Hounsfield units (HU) were measured. Results Non-contrast CCT accurately detected MI in 57 patients with irreversible perfusion defect on MPI, yielding a sensitivity of 92%, specificity of 72%, negative predictive value (NPV) of 90%, and a positive predictive value (PPV) of 77%. On a per myocardial region analysis, non-contrast CT showed a sensitivity of 70%, specificity of 85%, NPV of 91%, and a PPV of 57%. The ROC curve showed that the optimal cutoff value of LV myocardium HU to predict MI on non-contrast CCT was 21.7 with a sensitivity of 97.4% and specificity of 99.7%. Conclusion Non-contrast CCT has an excellent agreement with MPI in detecting chronic MI. This study highlights a novel clinical utility of non-contrast CCT in addition to assessment of overall burden of atherosclerosis measured by CAC.

Cardiac computed tomography (CT) requires intravascular injection of iodinated contrast agent to visualize the cardiac chambers, large vessels, and coronary arteries. Currently, the standard injection protocol used clinically is uniphasic (fixed volume of contrast agent injected at a single flow rate). This results in non-uniform enhancement of the blood pool in some patients. The purpose of this work was to

The purpose of this study was to determine imaging predictors of aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) and the agreement and reproducibility of cardiovascular magnetic resonance (CMR), cardiac computed tomography (CCT), and transthoracic echocardiography (TTE) in aortic root assessment.The optimal imaging strategy for planning TAVI is unclear with a paucity of comparative multimodality imaging data. The association between aortic root morphology and outcomes after TAVI also remains incompletely understood.A total of 202 consecutive patients assessed by CMR, CCT, and TTE for TAVI were studied. Agreement and variability among and within imaging modalities was assessed by Bland-Altman analysis. Postoperative AR was assessed by TTE.Of the 202 patients undergoing TAVI assessment with both CMR and TTE, 133 also underwent CCT. Close agreement was observed between CMR and CCT in dimensions of the aortic annulus (bias, −0.4 mm; 95% limits of agreement: −5.7 to 5.0 mm), and similarly for sinus of Valsalva, sinotubular junction, and ascending aortic measures. Agreement between TTE-derived measures and either CMR or CCT was less precise. Intraobserver and interobserver variability were lowest with CMR. The presence and severity of AR after TAVI were associated with larger aortic valve annulus measurements by both CMR (p = 0.03) and CCT (p = 0.04) but not TTE-derived measures (p = 0.10). Neither CCT nor CMR measures of annulus eccentricity, however, predicted AR after TAVI (p = 0.33 and p = 0.78, respectively).In patients undergoing imaging assessment for TAVI, the presence and severity of AR after TAVI were associated with larger aortic annulus measurements by both CMR and CCT, but not TTE. Both CMR and CCT provide highly reproducible information in the assessment of patients undergoing TAVI.

This review deals with noninvasive imaging for risk stratification and with a conceptual approach to the selection of noninvasive tests in patients with suspected or known chronic coronary ar- tery disease (CAD). Already widely acknowledged with SPECT, there is an increasing body of literature data demonstrating thatCTcoronarycalciumassessmentisalsoofprognosticvalue. The amount of coronary atherosclerosis, as can be extrapolated from CT coronary calcium

The American College of Cardiology Foundation (ACCF), along with key specialty and subspecialty societies, conducted an appropriate use review of common clinical scenarios where cardiac computed tomography (CCT) is frequently considered. The present document is an update to the original CCT/cardiac magnetic resonance (CMR) appropriateness criteria published in 2006, written to reflect changes in test utilization, to incorporate new clinical data, and to clarify CCT use where omissions or lack of clarity existed in the original criteria (1). The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Ninety-three clinical scenarios were developed by a writing group and scored by a separate technical panel on a scale of 1 to 9 to designate appropriate use, inappropriate use, or uncertain use. In general, use of CCT angiography for diagnosis and risk assessment in patients with low or intermediate risk or pretest probability for coronary artery disease (CAD) was viewed favorably, whereas testing in high-risk patients, routine repeat testing, and general screening in certain clinical scenarios were viewed less favorably. Use of noncontrast computed tomography (CT) for calcium scoring was rated as appropriate within intermediate- and selected low-risk patients. Appropriate applications of CCT are also within the category of cardiac structural and functional evaluation. It is anticipated that these results will have an impact on physician decision making, performance, and reimbursement policy, and that they will help guide future research.

Results. On MSCT 36% had normal coronaries, 24% had significant CAD requiring revascularization, and the remainder had mild CAD. MSCT had reasonably high diagnostic accuracy at segment level (negative predictive value of 95%, positive predictive value 81%, ...

Methods and Results— We analyzed 356 patients (mean age, 53±12 years; 62% men) with acute chest pain and inconclusive initial emergency department evaluation. Patients underwent 64-slice contrast-enhanced cardiac computed tomography before hospital admission. ...

We report a case of a 26-year-old female, who presented at 34 weeks of an uncomplicated pregnancy with an acute ST elevation anterior wall myocardial infarction. Cardiac catheterization suggested a left main coronary artery dissection with pseudoaneurysm formation. The patient&#x27;s ...