Comparative study of five preoperative methods for the localization of accessory pathways in the Wolff-Parkinson-White syndrome

One hundred and thirty-four cases of Wolff-Parkinson-White syndrome were studied to evaluate the relative usefulness of electrocardiography (ECG), electrophysiological studies (EPS), body surface mapping (BSM), gated blood-pool phase analysis (nuclear studies), and vectorcardiography (VCG) in the localization of the accessory pathway (ACP). In comparison with the final localization verified by intraoperative studies, 93.4% in 8-region ACP localization (97.7% in 4-region ACP localization) could be correctly localized by ECG using our criteria, 83.9% (86.8%) by EPS, 82.6% (95.8%) by BSM, 78.8% (87.7%) by nuclear studies, and 67.3% (78.0%) by VCG. It was concluded that: (a) ACP can be localized preoperatively with considerable accuracy by using our simple ECG criteria. (b) The EPS method has some limitation, especially with respect to 8-region ACP localization. (c) Our observation showed no evidence that BSM, VCG, or nuclear studies were superior to ECG in ACP localization. (d) Among the 5 methods studied, ECG and EPS appear to be the appropriate procedures for preoperative ACP identification.