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During the last few decades, significant strides have been made in the field of noninvasive imaging for the patient with congenital heart disease. Echocardiography and MRI continue to provide improved means of anatomic and functional assessment in children and adults with congenital heart lesions. This review reports some of the recent advances in tissue Doppler, strain rate, and integrated backscatter, and highlights exciting current and future potential developments in their application. We also discuss advances in MR in evaluation of cardiac anatomy and function in congenital heart disease.

Advances in ultrasound technology will continue to expand the utility of echocardiography in the assessment of structural and functional cardiac disease in children. Tissue Doppler imaging and dobutamine stress echocardiography are 2 promising clinical applications that are expected to become increasingly used with time. Advances in data compression technology, including JPEG and MPEG techniques, will significantly affect digital archival and transmission of echocardiograms, which also have clinical implications, particularly in the expanding use of telemedicine. Continued research and clinical experience will further define the ultimate roles of these technologies in the future.

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.

This study compared gradient echo magnetic resonance imaging, spin echo magnetic resonance imaging, echocardiography, and echocardiography with x-ray cineangiography in the evaluation of major aortopulmonary collateral arteries. Twelve patients (ages 9 months to 35 years, mean 11 +/- 11 years) with known or suspected major aortopulmonary collateral arteries were studied. The aortic insertion and proximal course of 29 major aortopulmonary collateral arteries demonstrated by x-ray contrast angiography were shown in all 29 cases by gradient echo magnetic resonance imaging but in only 23 of the 29 cases by spin echo magnetic resonance imaging. Color Doppler-echocardiography detected aortopulmonary collateral arteries in four patients but did not define the proximal course or distal anatomy. Gradient echo images of distal aortopulmonary collateral anatomy were qualitatively superior to spin echo images. The contrast-to-noise ratio between the vessel lumen and adjacent lung was greater for gradient echo (6.06 +/- 2.91) than for spin echo (1.45 +/- 1.13)(p < 0.05). Gradient echo magnetic resonance imaging is a useful method for identification and characterization of aortopulmonary collateral arteries in patients of all ages and is superior to spin echo magnetic resonance imaging and echocardiography.

Twelve patients more than 8 years of age with complex congenital heart disease were evaluated prospectively with nuclear magnetic resonance (NMR) imaging and with echocardiographic and angiographic imaging techniques. The subpulmonary region, main pulmonary artery, right and left pulmonary arteries, and aorticopulmonary shunts were clearly visualized by means of NMR imaging in all patients. Angiography defined the subpulmonary region and main pulmonary artery in all patients, the right and left pulmonary arteries along their length in 11 of 12 patients, and aorticopulmonary shunts in seven of eight patients. Except for the right pulmonary artery, echocardiography defined the remaining structures in less than or equal to 50% of patients. Measurement of the pulmonary artery diameters on NMR images correlated well with the angiographic measurements of both the left (r = 0.96) and right (r = 0.94) pulmonary arteries. These results suggest that NMR imaging may be the preferable noninvasive imaging technique for defining the anatomy of the subpulmonary region, main and left pulmonary arteries, and aorticopulmonary shunts in older patients with congenital cardiovascular disease and that it compares well with the angiographic standard.

Two-dimensional echocardiography can diagnose hypoplastic left heart syndrome. However, with the advent of the possibility of palliative open heart surgery, complete anatomic diagnosis is necessary. The anatomic findings of 15 neonates with hypoplastic left heart syndrome (age 1 to 10 days, mean 4.1) who had two-dimensional Doppler echocardiographic studies were compared with the results obtained by angiography (6 cases), surgery (11 cases) and autopsy (8 cases). Complete two-dimensional echocardiographic examination of the aortic arch, pulmonary and systemic venous return, atrial septum, ductus arteriosus and proximal coronary arteries was possible in all 15 neonates and correctly diagnosed hypoplastic left heart syndrome in each. Anatomic two-dimensional echocardiographic assessment was accurate in 13 (86%) of the 15 neonates and there were no false positive results. Undiagnosed associated abnormalities were hypoplasia of a left pulmonary artery in one patient and left superior vena cava in another. Accurate quantitation of the size of the tricuspid valve anulus, ascending aorta, pulmonary anulus and right and left pulmonary arteries was possible. Doppler examination was performed in seven patients and confirmed retrograde aortic arch flow and right to left systolic shunting in the patent ductus arteriosus. In selected neonates, surgical palliation can be attempted without angiography.

Evaluation for patent ductus arteriosus by both Doppler examination and direct two-dimensional echocardiographic visualization has been reported in infants and children. However, visualization of a patent ductus arteriosus in preterm infants with lung disease has been difficult. Using a recently developed 7.5 MHz mechanical scanner with interfaced two-dimensional directed pulsed Doppler ultrasonography, 36 examinations were performed from a suprasternal approach in 27 patients (age range 1 day to 3 months, mean 18 days; weight range 490 to 2,500 g, mean 1,260). Complete imaging for evaluation of patency of the ductus arteriosus was successful in 33 (92%) of 36 examinations, and imaging of the pulmonary end of the ductus arteriosus was successful in all. In 18 examinations, the ductus arteriosus was closed by both two-dimensional echocardiography and Doppler examination. In four cases the ductus arteriosus was widely patent by both two-dimensional echocardiography and Doppler examination. Eleven echocardiographic examinations revealed a narrowed ductus arteriosus, and of these, 10 (91%) showed Doppler findings of patent ductus arteriosus. It is concluded that combined two-dimensional/Doppler echocardiographic assessment allows confident detection of both a large unrestrictive and a small, stenotic patent ductus arteriosus in preterm infants with lung disease.

Obstruction to pulmonary venous return may be associated with a number of congenital cardiovascular abnormalities occurring both before and after surgery. Hemodynamic assessment by cardiac catheterization is often difficult. A noninvasive method for detection and quantitation of obstruction to systemic ventricular inflow would be clinically useful. Two-dimensionally directed pulsed and continuous wave Doppler echocardiography was performed before cardiac catheterization in 31 patients thought clinically to have possible obstruction to left ventricular inflow or pulmonary venous return. Primary diagnoses included transposition of the great arteries after the Mustard or Senning procedure in nine patients, total anomalous pulmonary venous connection in nine (in two after surgical repair), cor triatriatum in eight (in four after surgical repair), congenital mitral stenosis in four (in one after surgical repair) and mitral atresia in one. Severe obstruction was defined as a mean pressure gradient at catheterization of greater than or equal to 16 mm Hg at any level of the pulmonary venous return or of the systemic ventricular inflow. Severe obstruction was predicted if Doppler examination measured a flow velocity of greater than or equal to 2 m/s across any area of inflow obstruction. At catheterization, 12 patients (39%) had severe obstruction to left ventricular inflow or pulmonary venous return and all obstructions were correctly detected by Doppler echocardiography. The site of pulmonary venous obstruction was localized by two-dimensionally directed pulsed Doppler study. Patients with a lesser degree of obstruction had a lower Doppler velocity, but none had a maximal Doppler velocity of greater than or equal to 2 ms/s.(ABSTRACT TRUNCATED AT 250 WORDS)

Combined two-dimensional and Doppler echocardiography has a high sensitivity and specificity for detection of isolated perimembranous ventricular septal defects. However, muscular or multiple ventricular septal defects may be difficult to diagnose with noninvasive methods, particularly in older children, necessitating angiography for accurate diagnosis. Detection of single and multiple ventricular septal defects with two-dimensional color flow mapping was compared with detection by standard two-dimensional imaging and Doppler. Both techniques were compared with four-chamber left ventricular angiography. Fifty-one patients (age 3 months to 25 years, mean 5.6 years) were studied. Eighteen had solitary ventricular septal defects, 18 had multiple ventricular septal defects, and 15 patients with intact ventricular septum served as a control group. At least one ventricular septal defect was detected by color Doppler and two-dimensional/Doppler methods in all patients with ventricular septal defect proved by angiography with no false positives. In the detection of multiple ventricular septal defects, the sensitivity of color Doppler was 72% and that of two-dimensional/Doppler was 38% (100% specificity in both). Color Doppler failed to identify multiple ventricular septal defects in five patients (two weighing less than 4 kg and three with reduced pulmonary blood flow). However, no large additional muscular defects were missed by imaging and color Doppler. Color Doppler is useful for the detection of ventricular septal defects and has higher sensitivity than two-dimensional/Doppler for multiple ventricular septal defects. The contribution of color Doppler appears to be in the detection of additional small muscular ventricular septal defects.