Chagas disease, which is caused by the parasite Trypanosoma cruzi
, is an important cause of heart failure. We investigated modifications in the cellular electrophysiological and calcium-handling characteristics of an infected mouse heart during the chronic phase of the disease. The patch-clamp technique was used to record action potentials (APs) and L-type Ca2+
and transient outward K+
changes were determined using confocal microscopy. Infected ventricular cells showed prolonged APs, reduced transient outward K+
and L-type Ca2+
currents and reduced Ca2+
release from the sarcoplasmic reticulum. Thus, the chronic phase of Chagas disease is characterised by cardiomyocyte dysfunction, which could lead to heart failure.