Clinical role, accuracy, and technical aspects of cardiovascular magnetic resonance imaging in infants.

Cardiovascular magnetic resonance imaging (CMRI) has been shown to be an important alternative to echocardiography and catheterization for diagnostic imaging in older patients with congenital heart disease. However, little information is available on its clinical role, accuracy, and technical aspects in infants. We retrospectively identified all patients <1 year of age who underwent a CMRI examination at our institution over a 4-year period (from 1999 to 2002) and reviewed their medical records. Ninety-nine CMRI examinations were performed in 91 patients (median weight 4.9 kg; range 1.2 to 16.3) at a median age of 102 days (range 1 to 358). Technical modifications were used to improve signal-to-noise ratio and temporal resolution, and specialized personnel and equipment were employed. All CMRI studies were performed under general anesthesia without any complications, and all outpatients (n = 44) were discharged the same day. The primary referral questions for CMRI were delineation of the thoracic vasculature (n = 54), assessment of possible airway compression (n = 25), evaluation of cardiac tumor (n = 6), and other (n = 14). For the thoracic vasculature group, findings at surgery (n = 37) and catheterization (n = 16) were concordant with the CMRI diagnoses. In the airway compression group, findings at surgery (n = 16) were also in agreement with CMRI findings. Tumor types by CMRI in the 3 patients with preoperative studies were confirmed by histologic results. Thus, CMRI has a limited but important diagnostic role in infants with cardiovascular disease. It is an accurate and safe method to delineate the thoracic vasculature, evaluate possible airway compression, and characterize cardiac tumors. CMRI may obviate cardiac catheterization and bronchoscopy in selected cases.