Study The Effect Of Dofetilide On Ventricular Myocardial Electrophysiological Property By MEA

Objective: The morphology of field potentials(FPs) was studied by microeiectrode arrays (MEA) mapping technique. The effect of amiodarone and dofetilide on ventricular myocardial field action potential duration (fAPD) and heart rate was mapped by MEA in guinea pigs. Methods: The morphology of field potentials(FPs) was mapped by a microeiectrode arrays (MEA) recording techniques in eighty guinea-pig. The eighty guinea-pigs were randomly divided into four groups: control group, amiodarone group, 10^-6 mol/1 and 10^-7 mol/1 dofetilide group. Both ventricular muscle field potential(FPs) and fAPD were observed by MEA. Results: These results showed that MEA could record sixty different shapes of fAPDs and ventricular activation sequence. The fAPD of ventricular myocytes was remarkably prolonged and the heart rate was reduced in both amiodarone and dofetilide group (P<0.001), still clear difference of fAPD was produced between 10^-6 mol/1 and 10^-7 mol/1 dofetilide groups by (P<0.001). Conclusions: MEA was a reliable 60 sites tissue potential mapping system in Langendorff perfused guinea pig's heart with Thyrode in 86 minutes means. MEA proved the prolongation of fAPD and reduction of heart rate by both amiodarone and dofetilide, and discrepancy of fAPD produced by10^-6 mol/1 and 10^-7 mol/1 difference dofetilide concentration. Thus MEA is an idea tool in investigating new antiarrhythmia drugs and proarrhythmia mechanism of antiarrhythmia drugs.