OPTIMAL LEAD SELECTION FOR DETECTION OF ST SEGMENT SHIFTS

A comparison was made to determine the ability of optimal sets of 2-6 unipolar leads and a normal Holter lead set to estimate ST potential d istributions changes induced by balloon inflation during angioplasty. The performance of these lead sets was compared to measurements observ ed in recorded 32-lead body surface maps. Unipolar lead potentials wer e estimated using a linear, least mean squared error estimator of the fetal body surface map. The correlation between maximum ST potential c hange in the body surface map and that predicted by the unipolar lead sets ranged from 0.84-0.93. The correlation between maxim um ST segmen t change measured from the body surface map and measured from the Holt er leads was 0.29. Therefore, shifts in ST segment potentials can accu rately be estimated from a small number of unipolar leads. lit contras t, current bipolar ambulatory recording techniques may introduce signi ficant bias to such estimates.