FIGURE 3.

Optical mapping recordings using voltage and calcium sensitive dyes. (A,B) Baseline fluorescence images of sample pig (A) and rabbit (B) hearts after loading with voltage sensitive dye (VSD) di-4-ANBDQBS (left panels). Normalized fluorescence signals, at 400 ms pacing cycle length (pig heart) and 350 and 250 ms pacing cycle lengths (rabbit heart), from representative pixels on the action potential duration (APD) maps at baseline (upper map) and after nifedipine administration (lower map; middle panels). Quantification of APD90 at baseline and after nifedipine administration in the pig and rabbit hearts (right panels). (C) Baseline fluorescence image of a second rabbit heart after loading with VSD di-4-ANBDQBS (left panel). Normalized fluorescence signals at 350 and 250 ms pacing cycle lengths from a representative pixel on the local activation time (LAT) map at baseline (upper map) and after flecainide administration (lower map; middle panels). Quantification of conduction velocity (CV) at baseline and after flecainide administration (right panel). (D) Baseline fluorescence image of a third rabbit heart after loading with calcium-sensitive dye rhod-2AM (left panel). Normalized fluorescence signals of calcium transients at 200 ms pacing cycle length from a representative pixel on the signal intensity map at baseline (upper map) and after isoproterenol administration (lower map; middle panels). All signals are from spatially averaged pixels (3 × 3 pixels). All maps shown used spatial and temporal filtering (3 × 3 to 5 × 5 pixels and third-order median filtering, respectively). The boxplots show data from each respective map considering values between the 1st and 99th percentile. LV, left ventricle; RV, right ventricle.