News | Computed Tomography (CT) | January 29, 2020

Rapid Aortic Aneurysm Growth Occurs in Presence of Blood Clot

The researchers used high resolution cross-sectional imaging with CT or MRI to assess 225 men with abdominal aortic aneurysm. Follow-up lasted, on average, more than three years.  Slightly more than half of patients had an intraluminal thrombus. The aneurysms of those with intraluminal thrombus were larger at baseline and grew by a rate of 2 mm per year, twice as fast as the 1 mm per year growth rate in people without intraluminal thrombus.

January 29, 2020 – The presence of a blood clot on the wall of the aorta in people with abdominal aortic aneurysms (AAA) is associated with more rapid, potentially dangerous growth in the aneurysm, according to a major study published Jan. 28 in the journal Radiology.[1] Researchers said the findings could help identify which patients need more aggressive treatment and more frequent follow-up imaging after their initial diagnosis.

The aorta is the major artery that carries oxygenated blood from the heart. Abdominal aneurysms occur when a bulge forms in the portion of the artery that runs through the abdomen. About 200,000 people in the U.S. are diagnosed with the condition every year. Over time, the wall can weaken and rupture. Ruptured abdominal aortic aneurysm is the 10th leading cause of death for men over age 55.

Decisions to surgically repair the aneurysm are based on its diameter. Patients with aneurysms larger than 5.5 cm are normally referred for repair, while those smaller than 5.5 cm are most commonly monitored with imaging at regular intervals. Ultrasound and cross-sectional imaging with CT or MRI are commonly used.

However, this diameter-based management strategy has limitations, as a considerable number of small aneurysms rupture, according to the study’s first author, Chengcheng Zhu, Ph.D., assistant researcher from the Department of Radiology and Biomedical Imaging at the University of California in San Francisco.

Zhu and colleagues focused their study on the intraluminal thrombus, a blood clot on the wall of the aorta at the location of the aneurysm. Intraluminal thrombi are present in the majority of aneurysms close to the repair threshold of 5.5 cm, and in a considerable number of smaller aneurysms. Despite their prevalence, the influence of these clots on abdominal aortic aneurysm growth and rupture risk is still not fully understood. 

“Intraluminal thrombus could be a new marker for aneurysm growth,” Zhu said.

The researchers used high resolution cross-sectional imaging with CT or MRI to assess 225 men with abdominal aortic aneurysm. Follow-up lasted, on average, more than three years.

Slightly more than half of patients had an intraluminal thrombus. The aneurysms of those with intraluminal thrombus were larger at baseline and grew by a rate of 2 mm per year, twice as fast as the 1 mm per year growth rate in people without intraluminal thrombus.

“An aneurysm with thrombus grows much faster than one without a thrombus,” Zhu said. “Our study looked at a large number of patients with a relatively long follow-up to confirm that thrombus is a new risk factor that may be potentially reported by radiologists.”

While the study did not examine the reasons why the presence of a thrombus had such a dramatic impact on aneurysms, Zhu noted that it likely has harmful biochemical effects on the vessel wall.

“When the vessel wall is covered with thrombus, the lack of oxygen weakens the wall of the vessel, making the aneurysm likely to grow faster and rupture,” he explained.

The findings suggest that imaging follow-up schedules may need to be adjusted for patients whose aneurysm has a thrombus. Current protocols for follow-up imaging are based on aneurysm size and do not account for the absence or presence of a thrombus.

“A patient at high risk may need closer monitoring,” Zhu said. “If in patients with a thrombus the aneurysm grows twice as fast, then shortening the surveillance interval could be considered.”

Zhu said more research is needed before thrombus detection is integrated into clinical protocols. For now, he said the findings provide another piece of information to use in determining the prognosis of patients with this potentially dangerous condition.

 

Reference: 

1. Dr. Zhu were Joseph R. Leach, M.D., Ph.D., Yuting Wang, M.D., Warren Gasper, M.D., David Saloner, Ph.D., and Michael D. Hope, M.D. Intraluminal Thrombus Predicts Rapid Growth of Abdominal Aortic Aneurysms.” Radiology. Published Online: Jan 28 2020. https://doi.org/10.1148/radiol.2020191723.

Related Content

#COVID19 #Coronavirus #2019nCoV #Wuhanvirus #SARScov2 U.S. Surgeon General Jerome Adams, M.D., M.Ph demonstrates how the general public can make their own face masks for non-clinical use.

U.S. Surgeon General Jerome Adams, M.D., M.Ph. demonstrates how the general public can make their own face masks for non-clinical use.

News | Coronavirus (COVID-19) | April 04, 2020 | By Melinda Taschetta-Millane
April 4, 2020 — The Centers for Disease Control and Prevention (CDC)
#COVID19 #Coronavirus #2019nCoV #Wuhanvirus #SARScov2

Getty Images

Feature | Coronavirus (COVID-19) | April 03, 2020 | By Melinda Taschetta-Millane and Dave Fornell
In an effort to keep the imaging field updated on the latest information being released on coronavirus (COVID-19), th
Recommended best practices for nuclear imaging departments under the COVIF-19 pandemic have been issues by the ASNC and SNMMI. #COVID19 #ASNC #SNMMI #Coronavirus #SARScov2
News | Coronavirus (COVID-19) | April 03, 2020
April 3, 2020 — A new guidance document on best practices to maintain safety and minimize contamination in nuclear im
Jeannie Danker, M.D. #COVID19 #Coronavirus #2019nCoV #Wuhanvirus #SARScov2

Jeannie Danker, M.D. Photo courtesy of The Ohio State University Wexner Medical Center

News | Coronavirus (COVID-19) | April 03, 2020 | By Melinda Taschetta-Millane
April 3, 2020 — The radiology world has lost a dedicated leader due to...
An estimated 44 million people worldwide are currently living with Alzheimer’s disease, the most common form of dementia. About 5.8 million people in the United States live with the disease, where it is the sixth leading cause of death overall. While there is not yet a cure for Alzheimer’s, researchers are working to find treatment options to delay its onset and prevent it from developing.

Image courtesy of Insightec

Feature | Ultrasound Imaging | April 02, 2020 | By Katie Caron
An estimated 44 million people worldwide are currently living with...
An example of Philips’ TrueVue technology, which offers photo-realistic rendering and the ability to change the location of the lighting source on 3-D ultrasound images. In this example of two Amplazer transcatheter septal occluder devices in the heart, the operator demonstrating the product was able to push the lighting source behind the devices into the other chamber of the heart. This illuminated a hole that was still present that the occluders did not seal.

An example of Philips’ TrueVue technology, which offers photo-realistic rendering and the ability to change the location of the lighting source on 3-D ultrasound images. In this example of two Amplazer transcatheter septal occluder devices in the heart, the operator demonstrating the product was able to push the lighting source behind the devices into the other chamber of the heart. This illuminated a hole that was still present that the occluders did not seal. Photo by Dave Fornell

Feature | Radiology Imaging | April 02, 2020 | By Katie Caron
A new year — and decade — offers the opportunity to reflect on the advancements and challenges of years gone by and p
#COVID19 #Coronavirus #2019nCoV #Wuhanvirus

Getty Images

Feature | Coronavirus (COVID-19) | April 02, 2020 | Jilan Liu and HIMSS Greater China Team
Information technologies have played a pivotal role in China’s response to the novel coronavirus...
#COVID19 #Coronavirus #2019nCoV #Wuhanvirus #SARScov2 Esaote won a tender launched by Consip on behalf of Civil Protection for the distribution of diagnostic equipment in Italy to face COVID-19 emergency.

Esaote won a tender launched by Consip on behalf of Civil Protection for the distribution of diagnostic equipment in Italy to face COVID-19 emergency.

News | Ultrasound Imaging | April 02, 2020
April 2, 2020 — Esaote, an Italian company among the world leader
#COVID19 #Coronavirus #2019nCoV #Wuhanvirus #SARScov2 Updated CT scoring criteria from AJR considers both lobe involvement and changes in CT findings to quantitatively and accurately evaluate the progression of COVID-19 pneumonia

CT scoring criteria were applied to images from sequential chest CT examinations. A, Initial chest CT image obtained 2 days after onset of symptoms shows small region of subpleural ground-glass opacities in right lower lobe, for CT score of 1. B, Chest CT image obtained on day 3 of treatment shows slightly enlarged region of subpleural ground-glass opacities with partial crazy-paving pattern and consolidation, for CT score of 3. C, Chest CT image obtained on day 5 of treatment shows partial resolution of consolidation, for CT score of 2. D, Chest CT image obtained on day 14 of treatment shows continued resolution of consolidation with minimal residual ground-glass opacities, for CT score of 1. Image courtesy of American Journal of Roentgenology (AJR)

News | Computed Tomography (CT) | April 02, 2020
April 2, 2020 — Updated computed t...