In a patient with intermittent type A Wolff-Parkinson-White (WPW) syndrome, the echocardiogram revealed late "double peaked" anterior motions (the former in the late systole, the latter in the early diastole) of left ventricular posterior wall during WPW conduction. In the same condition, phonocardiographic and mechanocardiographic observations indicated a prolonged electromechanical interval, but the external isovolumic contraction time (EICT) and left ventricular ejection time/EICT ratio remained unaltered. In addition, definite but slight alteration in the spatial ventricular gradient was observed. These observations by non-invasive methods present additional informations supporting the concept that conduction abnormalities per se are not responsible for abnormalities of ventricular function unless there is severe underlying heart disease.