Keywords:
Cardiac, Paediatric, MR, Diagnostic procedure, Sedation, Congenital
Authors:
M. Shariat1, L. Mertens1, L. Grosse-Wortmann1, M. Seed1, F. Golding1, L. Mercer-Rosa 2, M. Harris2, K. Whitehead2, C. Li2, M. Fogel2, S.-J. Yoo1; 1Toronto, ON/CA, 2Philadelphia/US
Methods and Materials
This was a prospective dual-center cohort study over a two-year period.
Following approval by the institutional research ethics boards and obtaining written parental informed consent,
all infants younger than 6 months old with complex congenital cardiovascular anomaly who had a comprehensive echocardiographic evaluation but required further cross-sectional imaging with CMR were recruited for this study.
The exclusion criteria included mechanical ventilation,
oxygen dependence,
feeding difficulties,
and any contraindication to CMR or CMR contrast media.
The feed-and-sleep study was performed by fasting the infant for a period of 4 hours prior to the scan.
Just before starting the CMR scan,
an intravenous line and electrocardiographic (ECG) leads were placed.
The infant was swaddled with one or two infant sheets before being placed in a vacuum immobilizer (MedVac® bag,
CFI Medical Solutions/Contour Fabricators,
Fenton,
MI,
USA) (Figure 1).
The infant was fed just prior to the scan.
A pulse oximetry probe and ear muffs were applied.
At this stage,
the infant was generally calm and in most cases had fallen asleep.
Air was then removed from the bag and the infant was contained within a rigid cradle shaped to his or her body.
This maneuver comfortably swaddled the infant and effectively limited the infant’s movement.
The lighting in the scanner room was dimmed to a level that would allow the patient to remain sleeping while permitting the staff to observe the infant.
If the infant woke up at any point during the study,
an extra feed of milk or sucrose solution was given which was generally effective.
All CMR examinations were performed on1.5 Tesla magnets (MAGNETOM Avanto,
Siemens Healthcare,
Erlangen,
Germany).
The unanswered clinical questions were listed and the CMR sequences were tailored and prioritized in the order of importance.
The length of each CMR examination was recorded as the time between the start of the first sequence and the end of last sequence.
A study was considered complete if all the required information was gathered,
image quality was optimal and the clinical questions were answered.
Descriptive statistical analysis was performed.
All continuous data is presented as means and standard deviations,
as well as ranges.