EVALUATION OF VENTRICULAR SEPTAL-DEFECT BY TRANSESOPHAGEAL ECHOCARDIOGRAPHY - INTRAOPERATIVE ASSESSMENT

The miniaturization of transesophageal echocardiography (TEE) probes, together with the development of the capability for biplane imaging fr om the esophagus, have increased the use of TEE in pediatric cardiolog y. The aim of this study was to evaluate the TEE findings in patients with ventricular septal defect (VSD) before and after closure primaril y by means of pediatric biplane probes. This study group included 69 p atients who underwent VSD closure as an isolated repair or as a part o f a definitive repair of a more complicated lesion. Ages ranged from 6 days to 15.6 years (median 1 year, 4 months), with operative weights ranging from 2.9 kg to 68 kg (median 10 kg). Preoperative and follow-u p transthoracic echocardiograms (TTE) were also performed. Intraoperat ive TEE was performed without complication in all 69 patients. Preoper ative results: (1) anatomic findings: Two muscular VSDs were detected by matrix TEE but could not be observed by TTE. A patient with preoper ative TTE diagnosis of an ostium primum ASD was found to have atrioven tricular (AV) canal by TEE. In three of six AV canal type VSDs, both T TE and TEE demonstrated left ventricular-right atrial shunting (2) aor tic regurgitation associated with VSD: Aortic regurgitation as a resul t of right coronary cusp prolapse was detected in one of five supracri stal VSDs in which the biplane or matrix TEE was used. In another two patients with perimembranous VSD, coronary cusp prolapse was detectabl e only by TEE, but no regurgitation was found; (3) tricuspid valve pou ch/aneurysm/straddling and chordal attachment: In 19 of 30 cases with perimembranous VSD and two of 6 cases with AV canal VSDs, the presence of a TV pouch was detected by TEE. Six of these 21 pouches were not s een on the TTE examination. In a patient with AV canal VSD, TV straddl ing was observed only by TEE; (4) diameter measurements (comparison be tween TTE and TEE): A moderate correlation was found when the largest VSD diameter measured in any plane by TTE was compared to the largest diameter measured by TEE (r = 0.76, p < 0.01) in 26 perimembranous VSD s. There was good agreement between diameter measurements obtained by TTE and TEE except with AV canal VSDs, where TEE diameter (especially transverse plane) was consistently larger than the TTE diameter, altho ugh the number of patients was too small for statistical analysis. Pos toperative results: Residual leaks and additional VSDs: In 25 patients residual leaks were diagnosed by TEE (23 of these were considered to be hemodynamically insignificant). The remaining two were recognized t o be clinically important and reoperated before the chest was closed. Intraoperative TEE with biplane capability is of significant value in defining anatomic features and physiologic characteristics of flow thr ough VSDs.