Jan Lam

Usefulness of biplane transesophageal echocardiography in neonates, infants and children with congenital heart disease.

A study was performed to assess the feasibility, additional diagnostic value and potential applications of biplane transesophageal echocardiography in neonates, infants and children. One hundred thirty-two consecutive studies were attempted in 111 anesthetized children with congenital heart disease. Longitudinal and transverse planes were compared using 3 methods: (1) separate 7 mm longitudinal and transverse pediatric transducers used sequentially; (2) an experimental 9 x 8 mm biplane pediatric transducer; and (3) a standard adult biplane transducer (12 x 9 or 13 x 9 mm). In all but 1 patient, a probe could be inserted. The longitudinal plane provided superior visualization of both the right and left ventricular outflow tracts, the interatrial septum, the main pulmonary artery, the ascending aorta and the right coronary artery. In 18 patients (16%), the longitudinal plane provided completely new diagnostic information that was not obtained with combined transthoracic and transverse plane transesophageal echocardiography. However, the transverse plane was mandatory for demonstration of the 4-chamber view, short-axis cross sections through the great arteries, the distal right pulmonary artery and bifurcation of the left coronary artery. The longitudinal plane is complementary to the transverse plane, but cannot substitute for it.

Transesophageal Echocardiography in Pediatric Patients: Preliminary Results

Transesophageal echocardiography was attempted in 59 pediatric patients with congenital heart disease in the operating room (n = 33) or during heart catheterization or in the intensive care unit (n = 26). Six different commercially available transducers were used with diameters ranging from 7 to 15 mm. Age ranged from 1 day to 16 years, and body weight ranged from 3.7 to 65 kg. Objectives of the study were to determine (1) minimum body weight in which transesophageal echocardiography with various probes is possible, (2) additional diagnostic value, and (3) potential applications. In three cases (one surgical and two nonsurgical) the probe could not be inserted. Minimum body weight was 17 to 20 kg for probes with a diameter of greater than or equal to 13 mm and approximately 12 kg for the 11 mm probes. A 7 mm probe, on the other hand, could be inserted easily in all patients (including a neonate) in whom transesophageal echocardiography was attempted. In 11 of 56 patients, additional diagnostic information was obtained. Thus, transesophageal echocardiography is feasible in the pediatric age group provided that special probes are used in small children. Additional diagnostic information can be obtained, and the technique is of value during cardiac surgery or balloon interventions for evaluation of the efficacy of the procedure and for monitoring ventricular function.

Transesophageal echocardiography with the use of a four-millimeter probe

Transesophageal echocardiography with the use of pediatric probes is nowadays commonly performed. However, in small children, insertion of a probe with a diameter of 7 mm may be traumatic or even impossible. We therefore tested a 17-element, 4 mm transverse plane probe in 136 pediatric patients, mainly in the operation room, catheterization laboratory, or the intensive care unit, and in three healthy adult volunteers. This probe was easy to insert, particularly during emergency situations, did not cause any complication in any patient, and provided satisfactory information despite the low number of elements. The use of a 4 mm transesophageal probe can improve the management of neonates with congenital heart disease in the operating room or the neonatal intensive care unit.

Ventricular Exclusion during Fontan Operation: An Evolving Technique

The modified Fontan operation, which consists of ventricular exclusion by obliteration of the right atrioventricular ostium, requires a technique that provides firm and permanent occlusion while preserving the atrioventricular node and bundle. Ten patients underwent such an operation. In 5 of them, closure of the right atrioventricular ostium was achieved by suturing a patch into the valve leaflets; in the other 5, the ventricle was excluded by a patch sutured into the right atrial wall above the annulus fibrosus. None of the patients who underwent this procedure experienced heart block postoperatively. However, three instances of late patch dehiscence occurred, each in the group of patients in whom the patch had been attached to the valve leaflets. We conclude that both patching techniques are safe as far as the atrioventricular node and bundle are concerned but that permanent occlusion is better obtained by implanting the patch into the atrial wall. Therefore, we prefer to use this technique.

Unusual combination of congenital heart lesions in a child with Noonan's syndrome

SummaryCongenital heart disease occurs in about 50% of patients with Noonans syndrome. We report the unusual association of stenotic dysplastic pulmonary valve, peripheral pulmonary stenosis, right aortic arch, aberrant left subclavian artery, and complex aortic coarctation in a 9-year-old boy with Noonans syndrome.