News | July 08, 2008

AHA Issues New Guidelines for CT, MR Coronary Angiography

July 9, 2008 – The American Heart Association recently issued new guidelines for computed tomography (CT) and magnetic resonance (MR) angiography, which state CT is the better imaging technology, but MR offers more patient safety because it does not use ionizing radiation.

The authors of the guidelines wrote noninvasive coronary CT and MR represent substantial advances that may ultimately be valuable for diagnosis of significant coronary artery disease. The chief advantages of coronary CT compared with MR are wider availability, higher spatial resolution, and more consistent, shorter examinations with better patient adherence. Advantages associated with coronary MR are a lack of radiation and a lack of administration of iodinated contrast material. However, the authors of the guidelines said both tests are presently suboptimal for patients with atrial fibrillation and other arrhythmias, and image quality may be further reduced by high body mass.

The new AHA guidelines state:

1. Neither coronary CT nor MR should be used to screen for coronary artery disease in patients who have no signs or symptoms suggestive of coronary artery disease.

2. The potential benefit of noninvasive coronary angiography is likely to be greatest and is reasonable for symptomatic patients who are at intermediate risk for coronary artery disease after initial risk stratification, including patients with equivocal stress-test results. Diagnostic accuracy favors coronary CT over MR for these patients.

3. Concerns regarding radiation dose limit the use of coronary CT in high-risk patients who have a very low pretest likelihood of coronary stenoses. Patients with a high pretest likelihood of coronary stenoses are likely to require intervention and invasive catheter angiography for definitive evaluation, so CT is not recommended for these individuals. Pronounced coronary calcification may negatively impact interpretability and accuracy of coronary CT so the usefulness of CT is uncertain in these individuals.

4. Anomalous coronary artery evaluation can be performed by either CT or MR. Radiation-protection concerns indicate that MR is preferred when it is available.

5. Reporting of coronary CT and MR results should describe any limitations to the technical quality of the examination and the size of the vessels, descriptions of coronary anomalies, coronary stenosis, and significant noncardiac findings within the field of view.

6. Continued research in cardiac CT and MR imaging is encouraged to determine the potential of these noncatheter-based modalities to detect, characterize, and measure atherosclerotic plaque burden, as well as its change over time or as the result of therapy. No multi-vendor trial data is available for coronary CT or for present whole-heart coronary MR, so the applicability of these methods beyond the reporting research centers is not known.

Specific recommendations for use of these technologies are expected to change along with advances in scanner hardware and software, the report said.

For more information: www.americanheart.org/presenter.jhtml?identifier=3004557

Related Content

Largest case series (n=30) to date yields high frequency (77%) of negative chest CT findings among pediatric patients (10 months-18 years) with COVID-19, while also suggesting common findings in subset of children with positive CT findings

A and B, Unenhanced chest CT scans show minimal GGOs (right lower and left upper lobes) (arrows) and no consolidation. Only two lobes were affected, and CT findings were assigned CT severity score of 2. Image courtesy of American Journal of Roentgenology (AJR)

News | Coronavirus (COVID-19) | May 29, 2020
May 29, 2020 — An investigation published open-access in the ...
United Imaging's uMR OMEGA is designed to provide greater access to magnetic resonance imaging (MRI) with the world’s first ultra-wide 75-cm bore 3T MRI.
News | Magnetic Resonance Imaging (MRI) | May 27, 2020
May 27, 2020 — United Imaging's...
The Philips Lumify point-of-care ultrasound (POCUS) system assessing a patient in the emergency room combined with telehealth to enable real-time collaboration with other physicians.

The Philips Lumify point-of-care ultrasound (POCUS) system assessing a patient in the emergency room combined with telehealth to enable real-time collaboration with other physicians.

News | Coronavirus (COVID-19) | May 26, 2020
May 26, 2020  — Philips Healthcare recently received 510(k) clearance from the U.S.
An example of DiA'a automated ejection fraction AI software on the GE vScan POCUS system at RSNA 2019.

An example of DiA'a automated ejection fraction AI software on the GE vScan POCUS system at RSNA 2019. Photo by Dave Fornell.

News | Ultrasound Imaging | May 26, 2020
May 12, 2020 — DiA Imaging Analysis, a provider of AI based ultrasound analysis solutions, said it received a governm
A new technique developed by researchers at UC Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from normal tissue. The team created a probe that generates two magnetic resonance signals that suppress each other until they reach the target, at which point they both increase contrast between the tumor and surrounding tissue

A new technique developed by researchers at UC Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from normal tissue. The team created a probe that generates two magnetic resonance signals that suppress each other until they reach the target, at which point they both increase contrast between the tumor and surrounding tissue. Image courtesy of Xiandoing Xue, UC Davis

News | Magnetic Resonance Imaging (MRI) | May 26, 2020
May 26, 2020 — Researchers at the University of California, Davis offers a...
Researchers from Tokyo Metropolitan University have surveyed the amount of gadolinium found in river water in Tokyo. Gadolinium is contained in contrast agents given to patients undergoing medical magnetic resonance imaging (MRI) scans, and it has been shown in labs to become toxic when exposed to ultraviolet rays. The researchers found significantly elevated levels, particularly near water treatment plants, highlighting the need for new public policy and removal technologies as MRI become even more commonp

Samples were taken along rivers around Tokyo. Measurements of rare earth element quantities indicate a clearly elevated amount of gadolinium compared to that in natural shale. Graphics courtesy of Tokyo Metropolitan University

News | Magnetic Resonance Imaging (MRI) | May 26, 2020
May 26, 2020 — Researchers from Tokyo Metropolitan...
Examples of chest CT images of COVID-19 (+) patients and visualization of features correlated to COVID-19 positivity. For each pair of images, the left image is a CT image showing the segmented lung used as input for the CNN (convolutional neural network algorithm) model trained on CT images only, and the right image shows the heatmap of pixels that the CNN model classified as having SARS-CoV-2 infection (red indicates higher probability). (a) A 51-year-old female with fever and history of exposure to SARS-

Figure 1: Examples of chest CT images of COVID-19 (+) patients and visualization of features correlated to COVID-19 positivity. For each pair of images, the left image is a CT image showing the segmented lung used as input for the CNN (convolutional neural network algorithm) model trained on CT images only, and the right image shows the heatmap of pixels that the CNN model classified as having SARS-CoV-2 infection (red indicates higher probability). (a) A 51-year-old female with fever and history of exposure to SARS-CoV-2. The CNN model identified abnormal features in the right lower lobe (white color), whereas the two radiologists labeled this CT as negative. (b) A 52-year-old female who had a history of exposure to SARS-CoV-2 and presented with fever and productive cough. Bilateral peripheral ground-glass opacities (arrows) were labeled by the radiologists, and the CNN model predicted positivity based on features in matching areas. (c) A 72-year-old female with exposure history to the animal market in Wuhan presented with fever and productive cough. The segmented CT image shows ground-glass opacity in the anterior aspect of the right lung (arrow), whereas the CNN model labeled this CT as negative. (d) A 59-year-old female with cough and exposure history. The segmented CT image shows no evidence of pneumonia, and the CNN model also labeled this CT as negative.  

News | Coronavirus (COVID-19) | May 19, 2020
May 19, 2020 — Mount Sinai researchers are the first in the country to use...
Advanced imaging data exchange is now live in Colorado due to the partnership of Health Images and the Colorado Regional Health Information Organization

Getty Images

News | Radiology Business | May 18, 2020
May 18, 2020 — 
Radiologists from Shanghai discuss modifying exam process and disinfecting exam room, while outlining personal protection measures during the coronavirus disease outbreak

(HIS = hospital information system, RIS = radiology information system) Image courtesy of American Journal of Roentgenology (AJR)

News | Coronavirus (COVID-19) | May 18, 2020
May 18, 2020 — In an open-access article published ahead-of-print