Features | Partner Sites | Information | LinkXpress
Sign In
Ampronix
Schiller
ElsMed

Predicting Heart Attack Risk with CT Angiography

By Medimaging International staff writers
Posted on 25 Feb 2013
Coronary computed tomography angiography (CCTA) is an effective tool for determining the risk of myocardial infarctions and other abnormal cardiac events in patients with suspected coronary artery disease (CAD) but no treatable risk factors, such as high blood pressure or high cholesterol.

“CCTA should be considered as an appropriate first-line test for patients with atypical chest pain and suspected but not confirmed coronary artery disease,” said the study’s lead author, Jonathon Leipsic, MD, FRCPC, from the University of British Columbia (Vancouver, BC, Canada).

Treatment for heart disease typically involves tackling modifiable cardiovascular risk factors such as high blood pressure, elevated cholesterol, diabetes, and smoking. However, some risk factors, such as family history, are not modifiable, and no risk models exist to help guide clinicians to identify those symptomatic patients without cardiac risk factors who are at an increased risk of death and myocardial infarction. “This scenario, where patients are symptomatic but have no cardiac risk factors, comes up often in clinical practice,” Dr. Leipsic said. “We lack a good tool to stratify these patients into risk groups.”

CCTA is a noninvasive test that has shown high accuracy for the diagnosis or exclusion of coronary artery disease in individuals. However, referral for patients with suspected coronary artery disease is frequently based on clinical risk factor scoring. Less is known about the prognostic benefits of CCTA in individuals with no medically modifiable risk factors.

In the first study of its sort, published online February 2013 in the journal Radiology, Dr. Leipsic and colleagues correlated CCTA results with the risk of major adverse cardiac events in 5,262 patients with suspected coronary artery disease but no medically modifiable risk factors. They culled the data from the Coronary CT Angiography Evaluation For Clinical Outcomes: An International Multicenter (CONFIRM) registry.

After a median follow-up of 2.3 years, 104 patients had experienced a major adverse cardiovascular event. The researchers identified a high occurrence of CAD in the study group, in spite of the lack of modifiable risk factors. More than 25% of the patients had non-obstructive disease or disease related to the accumulation of plaque in the arteries, and another 12% had obstructive disease with a greater than 50% narrowing in a coronary artery. “We found that patients with narrowing of the coronary arteries on CT had a much higher risk of an adverse cardiac event,” Dr. Leipsic said. “This was true even for those without a family history of heart disease.”

Both asymptomatic and symptomatic patients with obstructive disease faced an increased risk for a major cardiac event. Contrarily, the absence of CAD on CCTA was associated with a very low risk of a major event.

The findings, according to the investigators, emphasize the need for improvement in the evaluation of individuals who may be overlooked by conventional techniques of CAD assessment. “If a patient shows up with vague symptoms and no medically modifiable risk factors, doctors often dismiss them or do a treadmill test, which won’t identify atherosclerosis and only has a modest sensitivity for detecting obstructive disease,” Dr. Leipsic said.

CCTA could help address this problem, Dr. Leipsic added, by helping to detect or rule out coronary artery disease and identifying those who may be helped with more intensive therapy. The researchers continue to examine the CONFIRM data with the goal of further clarifying the association between plaque and myocardial infarctions and the longer-term outlook for patients with coronary artery disease.

“We are now collecting data to determine the prognostic value of CCTA after five years or more of follow-up, which will be very important for the field,” Dr. Leipsic stated.

Related Links:
University of British Columbia



Channels

MRI

view channel
Image: The ScanMed PROCURE wearable MRI prostate coil (Photo courtesy of ScanMed).

World’s First Wearable Prostate Coil Facilitates Simple and Accurate Positioning

A wearable prostate coil has been designed to be similar to wearing a diaper; this specialized magnetic resonance imaging (MRI) device positions the multiple antenna elements as close as possible to the... Read more

Nuclear medicine

view channel

PET-CT Imaging Forecasts Survival of Lymphoma Better Than Standard Imaging Strategies

Positron emission tomography-computed tomography (PET-CT) imaging is more accurate than traditional CT scanning in gauging response to treatment and predicting survival in patients with follicular lymphoma, and should be used routinely in clinical practice. The findings were published September 18, 2014, in the journal... Read more

General/Advanced Imaging

view channel
Image: From left, Guy Genin, PhD, John Boyle and Stavros Thomopoulos, PhD, watch as a sample is exposed to stress and force. They have developed algorithms that may lead to the ability to identify weak spots in tendons, muscles and bones (Photo courtesy of Washington University in St. Louis).

Image Analysis Algorithms Devised to Find Weak Spots in Muscles, Tendons, and Bones prone to Tearing, Breaking

Researchers have developed algorithms to detect weak spots in muscles, tendons, and bones predisposed to tearing or breaking. The technology, which needs to be further refined before it is used in patients,... Read more

Imaging IT

view channel

Interactive Dashboard and Visualization Tool Designed for Oncologists

A new tool has been developed to help users of an information system for radiation oncology to analyze data and use metrics to help make more informed decisions. Varian Medical Systems (Palo Alto CA, USA), a developer of cancer treatment technology and informatics software for managing comprehensive cancer clinics, will... Read more

Industry News

view channel

Global Partnership Provides Treatment Planning Support for Modulated Arc Radiotherapy

Varian Medical Systems (Palo Alto, CA, USA) Eclipse treatment planning software can now be used to plan modulated arc radiotherapy (mARC) treatments at sites using Siemens Healthcare (Erlangen, Germany) medical linear accelerators. Varian Medical Systems and Siemens Healthcare presented their range of solutions that... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.