SCMR meeting advances clinical horizons of cardiac MRI

Techniques destined to improve the surgical response to aortic valve surgery, 3T whole-heart coronary MR angiography assessments approaching the accuracy of multislice CTA, definitive diagnoses for previously unexplained heart failure, and improved risk assessments are among the clinically relevant themes that will be addressed Feb. 1 to 3 at the 2008 Society for Cardiovascular Magnetic Resonance in Los Angeles.

More than 1000 radiologists and cardiologists are expected to attend the meeting at the Century Plaza Hotel. It will feature 150 invited talks and 400 presentations and posters.

Numerous papers break new ground in the advancement of CMR applications, system design, pulse sequence development, and research data investigating the modality's appropriate place in routine practice, according to scientific program chair Dr. Matthias Friedrich.

Past attendees of the SCMR meeting have come to understand its role in setting the agenda for cardiac MR research and in presenting subsequent studies that answer questions previously posed at the annual gathering. Plenary sessions at previous meetings, for example, emphasized the need for research into the potential applications of CMR for heart failure and cardiomyopathy. Studies presented at the 2008 meeting will advance the clinician's ability to phenotype cardiomyopathies such as hemochromatosis, amyloidosis, sarcoidosis, and myocarditis.

"The assessment of tissue abnormalities, such as scar and its regional distribution, will give you the clue you need to make a diagnosis," Friedrich said. "All those nonischemic cardiomyopathies that have typically been very difficult to diagnosis have become much more approachable with CMR."

Papers by young investigators Dr. Saul Myerson and Dr. Joseph Selvanayagam are highlights of this year's show. A study by Myerson, a CMR researcher at Oxford University, potentially establishes a more effective standard for determining when aortic valve surgery should be performed, Friedrich said. The current standard (an end-diastolic diameter of 55 mm) often appears after the heart has been damaged. Myerson's study indicates that the volume of regurgitated blood flow and left ventricle volume are better and earlier indicators for needed intervention.

"This would have a tremendous impact on patients because it would allow for much better surgical planning," Friedrich said.

Selvanayagam worked with Myerson in the same Oxford University lab before accepting a CMR research position with Flinders University in Adelaide, Australia. He will fly to Los Angeles to present a clinical study using delayed-enhancement CMR to measure the extent of myocardial injury caused by revascularization. His results show that CMR may be a stronger prognostic marker for the affects of intervention-related injury than cardiac troponin measurement, Friedrich said.

Researchers from China will present data demonstrating the value of contrast-enhanced whole-heart coronary MRA performed on a 3T imager. Radiologist Dr. Qi Yang of Xuanwu Hospital in Beijing will present results approaching the diagnostic accuracy of volumetric whole heart CTA imaging, Friedrich said.

"Whole-heart CMR doe not have the spatial resolution of whole-heart CTA, but its sensitivity and specificity are in the 90% range," he said.

Whole-heart CMR would spare the patient the radiation exposure of CTA and could be added to the standard CMR protocols for assessing myocardial viability, wall motion, and left ventricular function, he said.

The opening plenary sessions will consider the growing accuracy of CMR for cardiac risk assessment. Ongoing clinical research has positioned CMR to address three levels of risk assessment, Friedrich said. It can detect risks for primary prevention of asymptomatic subjects. In this context, it can assess their risk of future cardiac events based on abdominal, pericardial, and intramyocardial fat accumulation.

For secondary prevention among symptomatic patients, CMR can provide unique information on the presence and stability of cardiovascular plaques.

'This technology could be used to assess the short-term prognosis of symptomatic patients and to plan therapy," he said.

Following myocardial infarction, CMR is already the modality of choice for assessing the appropriateness and potential effectiveness of revascularization. That research continues. Researchers are gaining a better appreciation about the relative roles of myocardial lesion size and heterogeneity in peri-infarcted tissue as depicted with delayed-enhancement CMR for risk assessment.

Research to be presented at the 2008 meeting will also consider the potential of microvascular damage, measured with CMR, as another tool to predict the risk of mortality following myocardial infarction.

For more information from the Diagnostic Imaging archives:

Perfusion predicts six-month survival

MRI demonstrates heart morphology and function

Consensus remains elusive for best left ventricle test