Isoarea maps during the PQRST sequence were computed in 22 healthy subjects and 48 patients with Wolff-Parkinson-White (WPW) syndrome. Thirty-eight patients with WPW were on no medication and 10 were treated with class I, II, or III antiarrhythmic drugs. Seventeen isoarea maps were recorded before and 17 were recorded after accessory pathway ablation. One patient had intermittent preexcitation. Body surface maps from all healthy subjects were similar, although the magnitudes of the maxima and minima showed significant variability. In all patients with WPW who were on no medication and in those on class I and II agents, PQRST maps were normal. Two patients taking amiodarone had abnormal PQRST maps, as did patients early after surgery. In the patient with intermittent preexcitation, PQRST maps were very similar during normal and preexcited beats. In conclusion, our results support the theory that the PQRST time integral reflects intrinsic recovery properties of the heart and is independent of the activation sequence.