Balloon atrial septostomy under transesophageal echocardiographic guidance

An evolving role of transesophageal echocardiography for the monitoring of interventional catheterization in children

BACKGROUND AND HYPOTHESIS

Transesophageal echocardiography (TEE) is increasingly utilized for the monitoring of interventional cardiac catheterization in children. The initial nondiscriminant use is giving way to a more selective approach. The current role and usefulness of this imaging modality are described.

METHODS

Between 1991 and 1995, 44 patients (mean age 7.4 +/- 5 years, weight 22.8 +/- 14.2 kg) underwent interventional cardiac catheterizations performed under TEE monitoring. The interventional procedures included (1) those involving creation, enlargement, or closure of an interatrial communication; (2) balloon dilatation of stenotic lesions; and (3) occlusion of arterial ducts. Transesophageal echocardiographic monitoring was judged to be either of great value, contributory, or of little use if the interventional procedure and choice of instrument relied heavily upon, was guided, or not affected by the information obtained from the ultrasonic investigation, respectively.

RESULTS

Transesophageal echocardiography was judged to be of great value in the monitoring of 18 (40%) procedures involving either the creation, enlargement, or closure of interatrial communications. This included 4 transseptal punctures, 4 blade septectomies for relieving restrictive atrial septal defects (n = 3) and an enlargement of the communication between the superior and inferior chambers of the divided left atrium in cortriatriatum, and 11 closures of a secundum atrial septal defect. Only the ultrasonic monitoring could clearly visualize the interatrial partition to provide real-time guidance on the positioning of the instrument to carry out the invasive procedures. Transesophageal echocardiography provided clear images of the hinge points of the aortic and mitral valves, the dimension of the narrowed pulmonary venous pathway in patients after venous switch operation. This facilitated the choice of the correct size of the balloon for dilatation in 11 patients (24%) and provided immediate postdilatation hemodynamic assessment. As for balloon dilation of subvalvar ventricular outflow tract obstruction (n = 3), aortic coarctation (n = 6), and occlusion of persistent arterial duct (n = 7), TEE offered no obvious advantage over fluoroscopy with angiography. The monitoring was judged to be of little value for the 16 (36%) procedures.

CONCLUSION

Transesophageal echocardiographic monitoring is of great value in interventional procedures involving the atrial septum and enhances interventional procedures involving obstructive lesions of the left heart in children.