Can intraoperative TEE correctly measure residual shunt after surgical repair of ventricular septal defects?
OBJECTIVE
No groups have yet succeeded in identifying the need for re-repair of residual shunt after surgical repair of ventricular septal defect (VSD) based on quantitative evaluation of the ratio of the pulmonary blood flow to the systemic blood flow (Qp/Qs) by transesophageal echocardiography (TEE). Hence, we studied the accuracy of Qp/Qs as estimated by intraoperative TEE.


METHODS
Twenty-six patients undergoing VSD closure were studied. After separation from the cardiopulmonary bypass, the presence and severity of residual leakage was evaluated by color Doppler image, and the Qp/Qs (TEE-derived Qp/Qs) was calculated by measuring the vessel diameter and the velocity-time integral of the flow profiles in the main pulmonary artery and left ventricular outflow tract. Transthoracic echocardiography (TTE) was performed at pre-discharge and at 6-12 months after the correction to confirm the presence and severity of residual leakage.


RESULTS
TEE detected only minor leakage, with no indication for re-repair, in 8 of the 26 patients. Nevertheless, TEE-derived Qp/Qs varied from 0.57 to 2.07 and were incorrect in 17 patients (65.4%). This meant that when TEE-derived Qp/Qs was outside the acceptable range, the patient was judged not to be in need of re-repair. TTE at pre-discharge confirmed trivial leakage in 3 patients in whom TEE had also identified similar leakages. These leakages were not observed at the follow-up TTE.


CONCLUSIONS
TEE-derived Qp/Qs lacks the accuracy required to play a crucial role in quantitatively measuring the severity of residual shunt, while two-dimensional TEE can reliably detect residual leakage after VSD closure and lead to optimal judgment on the need for re-repair.
Kurokawa
Satoshi
S
Department of Anesthesiology, Faculty of Medicine, Tokyo Women's Medical University, 8-1 Kawadacho, Shinjuku-ku, Tokyo 162-8666, Japan. satokuro@sea.plala.or.jp
Honma
Takayuki
T
Taneoka
Miki
M
Imai
Hidekazu
H
Baba
Hiroshi
H
Nomura
Minoru
M
D000293:Adolescent; D000465:Algorithms; D001166:Arteriovenous Shunt, Surgical; D001784:Blood Gas Analysis; D006328:Cardiac Catheterization; D002648:Child; D002675:Child, Preschool; D017548:Echocardiography, Transesophageal; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006345:Heart Septal Defects, Ventricular / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007223:Infant; D008297:Male; D011652:Pulmonary Circulation / Q000502:physiology; D012086:Reoperation; D055815:Young Adult