FLORENCE, Italy, May 13 (UPI) -- Using a technique to reduce motion from breathing, researchers in Switzerland found higher quality cardiac imaging is possible, faster and with less discomfort to patients.
High frequency percussive ventilation during cardiac magnetic resonance imaging was shown in exploratory research to reduce the motion of patients comfortably and allow doctors to capture more precise images, according to researchers at University Hospital Lausanne.
HFPV is a ventilator delivering 300 to 500 small ventilations per minute, compared to the 10 or 15 larger breaths normally taken, keeping the chest and lungs relatively still while also continuing to provide oxygen to the body.
Typically, cardiac MRI scans are captured in steps, with patients asked to hold their breath for each image, recover and repeat for the next one. With the new technique, however, patients do not need to hold their breath -- or even breathe on their own -- and a full image of the heart can be taken at once.
"In many imaging techniques, but particularly in CMR, you need a relatively long acquisition time and must correct for respiratory motion," Dr. Juerg Schwitter, director of the Cardiac MR Center at the University Hospital Lausanne. "For decades we have had to correct for respiration when estimating the position and motion of the heart by CMR, and this is not always accurate."
For the study, presented today at the annual meeting of the European Association for Cardiovascular Imaging, researchers recruited one 38-year-old healthy volunteer and one 55-year-old patient with a thymic lesion to undergo imaging using HFPV.
The ventilation did not pose problems for either participant, though Schwitter said some patients in the past reported their chest felt inflated, but "otherwise it feels okay."
In the images, researchers reported they could clearly see coronary arteries, and that lung volumes appeared "frozen" and pulmonary vessels could also be seen clearly.
The big upshot, Schwitter said, is that eliminating the need to work around breathing motion means the images are as precise as possible.
Calling the small study "promising first steps" to using HFPV, the researchers say much more testing needs to be done, both to refine methods and the quality of images from the technique, as well as to test the comfortability to patients in a much larger group.
"The possibilities with high frequency percussive ventilation are huge," Schwitter said. "You could run all the CMR sequences in one batch, which would be much faster. Data could be acquired constantly with fewer artifacts. We might be able to use this technique for diagnosis of sicker patients, who find breath holding difficult and need the imaging to be done quickly."