when the hearts were perfused with isoprenaline ( 1 mumol/liter ) in the presence of tropolone ( 100 mumol/liter ) at 40-41 degrees c , the duration of ventricular fibrillations was significantly prolonged , but the incidence of ventricular fibrillations was similar to that produced with isoprenaline ( 1 mumol/liter ) alone .
C0042510
ventricular fibrillations
C0022245
isoprenaline