Figure 6. Effects of bupivacaine on the incidence of conduction disturbances and arrhythmias during simulated reperfusion. For each time interval (2 min) of the reperfusion period (30 min), values are expressed as percentages of preparations presenting (1) conduction disturbances, or conduction blocks between the two myocardial regions (closed circles) and loss of excitability in altered zone (AZ, open circles); and (2) repetitive responses induced by an extrastimulus (ES, open bars) and spontaneous arrhythmias (closed bars). Patterns are shown in the absence of drug (control) and in the presence of 1 micro Meter, 5 micro Meter, and 10 micro Meter bupivacaine.