Exploring major breakthroughs in cardiac imaging
Recent advancements in cardiac imaging are revolutionizing the field, offering more precise diagnostics and better patient outcomes. Ron Blankstein, MD, director of cardiac computed tomography (CT) at Brigham and Women’s Hospital and a professor of medicine and radiology at Harvard Medical School, spoke with Cardiovascular Business about the latest developments in cardiac MRI, nuclear imaging, and CT.
Nuclear imaging: Enhancing diagnostic precision with PET
In nuclear imaging, one significant advancement is the use of positron emission tomography (PET) for quantifying myocardial blood flow at both rest and stress. Blankstein highlighted the growing adoption of myocardial blood flow reserve, a technique that significantly enhances the accuracy of PET exams. This method improves the detection of diffuse atherosclerosis and microvascular disease, offering greater prognostic value in patients who present without clear blockages of the larger arteries. Additionally, he said, it bolsters the confidence in negative test results, ensuring more accurate diagnoses.
"It enhances the prognostic value of PET. Ultimately it just makes us more accurate when we say a test is negative and there's no disease if that myocardial blood flow ratio is normal. That gives us a lot more confidence in those results," Blankstein explained.
Another exciting application of nuclear imaging is the detection of amyloidosis, which has garnered attention due to new drug therapies now available to treat the condition. Nuclear imaging is also being used more and more for identifying infections and cardiac sarcoidosis through FDG imaging, he said.
Read more about advancements in cardiac nuclear imaging
Cardiac MRI: Advanced techniques for myocardial characterization
Cardiac MRI has seen remarkable advancements, particularly in its ability to characterize the myocardium. Blankstein noted the importance of quantifying myocardial characteristics, such as T1 and T2 signals and extracellular volume (ECV). These quantitative parametric imaging techniques have transformed the diagnosis of diseases like amyloidosis and non-ischemic cardiomyopathies. By detecting fibrosis and even specific types of fibrosis that were previously undetectable, MRI is providing more comprehensive insights into the severity of these conditions.
"One of the big strengths of cardiac MRI is the ability to characterize diseases of the myocardium. These may be infiltrative diseases like amyloid or sarcoid, or they can be cardiac masses. One of the biggest changes in MRI in the last decade, has been the ability to quantify different characteristics in the myocardium," Blankstein said.
Artificial intelligence (AI) is also making its mark in cardiac MRI, streamlining both the acquisition and post-processing of imaging data. AI algorithms are speeding up the quantification of ventricular volumes, function, and parametric mapping, enhancing the efficiency and accuracy of cardiac MRI.
Find out more trends in an overview of MRI market and technology trends.
Cardiac CT: Breakthroughs in photon-counting and quantitative plaque imaging
Cardiac CT is another rapidly advancing area, and Blankstein discussed some advancements he observed at the recent Society of Cardiovascular Computed Tomography (SCCT) meeting. Blankstein, a former SCCT president, said photon-counting CT is emerging as a game-changing technology. It boasts dramatically improved image resolution, now down to 0.2 millimeters, compared to the previous standard of 0.6 millimeters. This advancement allows for a more accurate detection of stenosis and reduced calcium and metal blooming inside arteries, enabling clearer visualization of the lumen inside stents and other pathologies.
Blankstein said quantitative coronary plaque imaging is another significant development in cardiac CT. Cardiac imagers or radiologists could manually assess the types of plaques and quantify them in the past, but it was too time-consuming. Artificial intelligence algorithms now offered by several vendors can now analyze the types of plaque and automatically quantify the plaque burden in each vessel segment in seconds. The ability to quantify both the amount and type of plaque is becoming increasingly valuable for predicting patient risk and guiding clinical trials.
"We're now seeing studies that are using quantitative plaque imaging as the endpoint for various clinical trials. So we can essentially see what is the effect of different therapies on the plaque," Blankstein explained.
Some cardiac imaging experts believe automated AI plaque assessments could be used to detect the start of coronary disease years before anything would show up in low-dose calcium scoring CT screenings the are now used to assess risk. Soft plaque assessments could be used in the years to come as a new screening method to show patients need to go on statin therapy, sometimes years before current guidelines recommend. These scans also could show patients who do not have any plaques and could help them avoid taking statins. Experts in the field have also said this technology could help better identify which patients would benefit from the more expensive, newer cholesterol-lower drugs now on the market.
Cardiac CT is also playing a crucial role in structural heart imaging, particularly in procedures related to the growing volume of procedures for transcatheter aortic valve replacement, transcatheter mitral valve replacement, tricuspid valve interventions, and left atrial appendage occlusion devices. Blankstein said CT imaging is now central to both pre- and post-procedural assessments, contributing to better planning and improved outcomes in structural heart disease interventions.
Dave Fornell has covered healthcare for more than 17 years, with a focus in cardiology and radiology. Fornell is a 5-time winner of a Jesse H. Neal Award, the most prestigious editorial honors in the field of specialized journalism. The wins included best technical content, best use of social media and best COVID-19 coverage. Fornell was also a three-time Neal finalist for best range of work by a single author. He produces more than 100 editorial videos each year, most of them interviews with key opinion leaders in medicine. He also writes technical articles, covers key trends, conducts video hospital site visits, and is very involved with social media. E-mail: dfornell@innovatehealthcare.com