Cine magnetic resonance imaging and color Doppler flow mapping in infants and children with pulmonary artery bands

Fludrocortisone in the management of an infant with a single ventricle and an overly tightened pulmonary artery band

We describe a 2-month-old female infant with a univentricular heart and overly tightened pulmonary artery band (PAB) resulting in hypercyanotic episodes. Despite adequate doses of morphine and a beta-blocker, she continued to have multiple hypercyanotic events per day. Treatment with fludrocortisone resulted in resolution of these episodes and allowed performance of a Glenn shunt at 3 half months of age. We conclude that fludrocortisone may be beneficial in the management of an overly tightened PAB until the patient is suitable for surgical intervention.

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.

Role of spin echo and cine magnetic resonance imaging in presurgical planning of heterotaxy syndrome. Comparison with echocardiography and catheterization

BACKGROUND

Patients with heterotaxy syndrome frequently have complex congenital cardiac and noncardiac malformations requiring detailed diagnostic evaluation by noninvasive as well as invasive imaging modalities for management planning. Recent advances in magnetic resonance imaging (MRI) techniques allow detailed delineation of cardiovascular anatomy and blood flow in young infants with rapid heart rates. The present study was undertaken to prospectively evaluate the role of MRI in the presurgical evaluation of patients with heterotaxy syndrome.

METHODS AND RESULTS

Between January 1 and December 31, 1992, 14 consecutive patients with heterotaxy syndrome and complex congenital heart disease were enrolled in a prospective protocol. After evaluation by echocardiography and cardiac catheterization, a tentative management plan was recorded. Subsequently, a MRI study was performed and surgical planning was reevaluated. MRI was found to be comparable to echocardiography in terms of length of examination and sedation requirements. Surgical planning was altered in four patients because MRI provided additional data not evident on echocardiography and catheterization. Comparison of diagnostic yield between echocardiography, catheterization, and MRI showed that MRI is superior to echocardiography and often to catheterization in delineation of systemic and pulmonary venous anatomy and their relation to mediastinal structures. When the anatomic and hemodynamic data obtained by echocardiography and MRI were considered together, cardiac catheterization data were necessary only to determination of pulmonary vascular resistance before Fontan operation.

CONCLUSIONS

MRI provides excellent anatomic and functional information that in some patients was not available by echocardiography or catheterization. Combined with echocardiography, MRI provides the high-quality diagnostic information necessary for management planning in most patients with heterotaxy syndrome. Cardiac catheterization is indicated when determination of pulmonary vascular resistance is necessary for decision making or when an interventional procedures is indicated.