Essen, Germany - A pilot study in 20 German centers suggests that cardiac magnetic resonance (CMR) imaging is safe, used frequently in clinical practice, provides high-quality images, and strongly affects patient care .
The main indications for CMR imaging were for patients with hypertrophic cardiomyopathy, CHF, and CAD.
Importantly, in 16% of cases, CMR imaging led to a new, unsuspected final diagnosis, and in 45% of cases, patient treatment was altered as a result of CMR findings.
"Having a constantly growing number of sites clearly demonstrates that CMR has already made its way into clinical routine," lead author Dr Oliver Bruder (Elisabeth Hospital, Essen, Germany) told heart wire . "However, more widespread use in some countries is still limited by the availability of CMR scanners, trained personnel, and low reimbursement rates."
The study is published online August 12, 2009 in the Journal of the American C ollege of Cardiology .Three main clinical indications
In the past five years CMR has been increasingly used in clinical practice in European countries such as Germany, Spain, the United Kingdom, and Portugal, coauthor Dr Anja Wagner (Drexel University College of Medicine, Philadelphia, PA) told heart wire . However, little information existed about the impact of this procedure on clinical practice.
To evaluate the indications, image quality, safety, and impact on patient management from using CMR imaging, the researchers analyzed data from the European Cardiovascular Magnetic Resonance (EuroCMR) registry for 11 040 consecutive patients who underwent CMR imaging in 20 centers in Germany.
Two-thirds of the patients had prior echocardiography, but CMR imaging was the first imaging procedure for 23% of the patients.
Severe complications requiring an overnight stay in hospital occurred in only five patients and were related to stress testing. No patients died during or due to the procedure. Mild complications occurred in 1.1% of patients.
Most patients (86%) did not require further imaging tests after CMR imaging.
The top three indications of CMR were workup of myocarditis/cardiomyopathies (32% of patients), risk stratification in CAD (31%), and myocardial viability imaging (15%).
"The presence and pattern of late gadolinium enhancement of the left ventricular myocardium is particularly helpful to differentiate the etiology of reduced left ventricular function in patients with new onset of heart failure," Bruder said.
Risk stratification in patients with suspected CAD is another important application, he added, noting that "single-center data, such as studies from the Eike Nagel group , have clearly demonstrated that patients with a normal stress CMR have an excellent prognosis."
These findings from multiple centers with imaging instruments from multiple vendors document the potential of CMR imaging for clinical, routine use, since CMR was capable of answering relevant clinical questions in more than 98% of cases, the authors write.Impact of CMR on prognosis
Next, the researchers will analyze data from the EuroCMR registry to determine the prognosis for patients who undergo CMR imaging for the three most common indications.
"As soon as these prognostic data are available, we speculate that CMR will become the main imaging procedure in many major clinical indications," Bruder said.
Unlike other procedures, CMR does not involve ionizing radiation. The current study also suggests that a substantial number of invasive coronary angiographies can be avoided in patients undergoing CMR stress testing for workup of suspected CAD, he added.
"We are very excited that we will soon expand our research [from currently more than 50 European centers] to the United States," Wagner, who will coordinate the US research, said.Implications for US practice
"In the US, CMR is available in clinical practice but is limited to large hospitals, academic centers, and advanced outpatient clinics," Dr Ricardo C Cury (Baptist Cardiac and Vascular Institute, Miami, FL), who was not involved in the study, commented to heart wire .
He identified three key findings:
The main clinical indications that MRI was used for in this registry are similar to those in the US.
MRI is a very safe procedure, even during pharmacological stress.
In two-thirds of patients, CMR affected patient management, and in 16% of patients there was a new important finding that was not suspected before the MRI study.
CMR can be used to replace or supplement more invasive procedures, he noted, and although the use of CMR in clinical practice is growing, this is occurring at a slower pace than in research, he added.
According to Cury, "More physicians need to be trained in CMR, and referring cardiologists need better education about CMR."
| The EuroCMR r egistry is supported by unrestricted educational grants from Medtronic, Novartis, Servier Societ é , and Siemens Healthcare. I ndustry grants w ere exclusively used for registry data management and analysis. CMR scans were funded by German health care provide rs.
Heartwire from Medscape © 2009
Cite this: Cardiac MRI shows promise in European study - Medscape - Aug 12, 2009.