Cardiothoracic MRIs in the ICU, are they effective enough?

For patients in the ICU setting, a successful cardiothoracic MRI is challenging yet possible and beneficial for patients with intact renal function, according to a new retrospective study published by Academic Radiology. Specially, the imaging procedure can diagnose myocardial and aortic disease in a critically ill population.  

Critically ill patients pose several problems that make imaging with gadolinium-based contrast agents like MRIs challenging. 

"Although the examination can be logistically difficult to perform, it can help provide diagnostic information that may not be obtained from other imaging modalities, especially when performed for the evaluation of myocardial disease," said lead author Narmadan Kumarasamy, MD, MPH, from the Montefiore Medical Center at Albert Einstein College of Medicine in New York. “Patient selection is essential to success and clinicians should aim to image patients with intact renal function and the absence of mechanical ventilation, as well as image patients for clinical indications of aortic and myocardial disease rather than for viability."

From 2005 to 2014, researchers identified adult ICU patients at Montefiore Medical Center scheduled for cardiothoracic imaging to participate in the study along with a control group of ICU patients scheduled for brain MRIs. Researchers then performed a chart review to identify factors impacting a patient's ability to have an MRI. Differences between completed and canceled exams for each group were also evaluated. 

According to the study, a total of 143 cardiothoracic MRIs and 1,011 brain MRIs were requested. Researchers found that cardiothoracic MRIs were less frequently completed, and patients were more likely male and young, less likely mechanically ventilated, more likely to require intravenous contrast and had longer examination times compared to brain MRI patients. 

Overall, myocardial disease was the most common indication for a cardiothoracic MRI exam, researchers concluded. Additional findings showed that successful completion of cardiothoracic MRI was associated with lower serum creatinine, higher glomerular filtration rate and no mechanical ventilation. Additionally, the most common reason for cancellation was renal failure for the cardiothoracic MRI cases and patient condition for the brain MRI cases, researchers wrote. 

"We believe that the differences between the two groups provide valuable insights to the challenges in performing cardiothoracic MRI in ICU patients," Kumarasamy said.