Cardiac magnetic resonance imaging (MRI) can be performed effectively on preterm infants without the need for anesthesia or sedation through the use of a high magnetic field strength -- 3.0-tesla instead of the standard 1.5-T MRI. Cardiac magnetic resonance imaging (MRI) can be performed effectively on preterm infants without the need for anesthesia or sedation through the use of a high magnetic field strength -- 3.0-tesla instead of the standard 1.5-T MRI.

Dr. Adrienne M. Foran of Imperial College, London and colleagues note that cardiac MRI in infants is challenging because of their small heart size and rapid heart rate, and image degradation due to movement. Because a small heart size would theoretically be an advantage in higher field strength imaging, the team of used 3.0-T cardiac MRI on 12 preterm infants without sedation or breath-holding to assess left ventricular function.

Median gestational age of the cohort was 29 weeks and median birthweight was 1,240 gm. Mean post-conception age at the time of the imaging study was 33 weeks.

"Imaging was successful for ten of 12 infants," the team reports in the July issue of Pediatrics.

Cardiac MRI allows assessment of "quantitative blood flow, intracardiac flow patterns, wall stress mapping, characterization of normal and damaged tissue and molecular events in the epithelium," Dr. Foran and colleagues observe.

They add, "Precise quantitative data on cardiac function should also allow studies of therapeutic intervention such as inotropic or antiinflammatory treatments for cardiac dysfunction with acceptable and practical sample sizes."

In their conclusion, Dr. Foran's team maintains that "Cardiac MRI has the potential to make significant contributions to research and the improvement of care for sick preterm infants.