Decreased amplitude of left ventricular posterior wall motion with notch movement to determine the left posterior septal accessory pathway in Wolff-Parkinson-White syndrome

Objective-To determine preoperatively, by analysing asynchronous left ventr icular wall motion, whether to approach through the right ventricle or the left ventricle when carrying out catheter ablation of the accessory pathway in Wolff-Parkinson-White syndrome, especially in patients with the pathway located on the septum. Methods-73 patients with manifest Wolff-Parkinson-White syndrome who underw ent successful catheter ablation were studied. Location of accessory pathwa y was classified as right ventricular side: right anterior paraseptum, righ t anterior, right lateral, right posterior, anterior septum, midseptum, rig ht posterior septum; left ventricular side: left posterior septum, left pos terior, left lateral, left anterior. Asynchronous systolic wall motion was analysed by cross sectional echocardiography. Results-Echocardiography showed that the amplitude of left ventricular post erior systolic wall motion was reduced when the pathway was located on the left ventricular side as opposed to the right ventricular side (mean (SD), 11.1 (1.7) v 12.9 (1.1) nun, p < 0.001), especially in patients with left p osterior septal accessory pathway (9.7 (0.8) mm). There were no overlapping values between the left posterior septal accessory pathway and the right v entricular side accessory pathway. Posterior wall notch motion was observed in all patients with a left posterior septal accessory pathway (9/9), but not at all in patients with pathways located on the right ventricular side of the septum. In patients with a septal accessory pathway, an ECG algorith m provided poor information (relatively low sensitivity, specificity, and p redictive value) for determining whether the subsite faced either the left (left posterior septum) or the right ventricle (anterior septum, midseptum, right posterior septum). Conclusions-Decreased amplitude of left ventricular posterior wall motion w ith notch movement is an important finding for accessory pathways located o n the left posterior septum. These findings provided clinically useful info rmation for determining whether to approach catheter ablation from the righ t or the left ventricle.