FIGURE 7.

Voltage and Ca²⁺ signal-to-noise in the normal zone (NZ), border zone (BZ), and infarct zone (IZ) from individual hearts. Voltage (black) and Ca²⁺ (red) S/N were plotted through depth for individual hearts in (A) NZ, (B) BZ, and (C) IZ. S/N in the IZ for two hearts [left and right panels in (C)] were plotted between depths where a voltage signal was detected. S/N values of 1 (no distinguishable signal) are illustrated by the dotted line. S/N values of 1.4 (indicating a real signal) are illustrated by the dashed line.