[Negative inotropic effect of flecainide on the post-ischemic heart with limited contractile function]

The hemodynamic effects of 7 min i.v. flecainide were examined in rats with postischemic left ventricular dysfunction. For quantification of contractile function the isovolumic left ventricular pressure generating capacity and dp/dtmax were determined. Fifteen min after infusion the isovolumic maximum pressure was reduced for 33 mm Hg after flecainide (2 mg/kg; n = 12), whereas in the controls only a minimal reduction (12 mm Hg; n = 13) was found; dp/dtmax was also significantly reduced after flecainide. The results indicate - in contrast to prior investigations on normal hearts - a considerable negative action of 2 mg/kg flecainide i.v. on postischemic myocardium with reduced contractile function.