CAT and myocardial infarction: Oral administration of betel leaf hydroalcoholic extract significantly modulated the haemodynamic of systolic pressure, diastolic pressure, mean arterial pressure (DAP, MAP and SAP) and parameters for ventricular function such as contractility (+LVdP/dt) and relaxation (LVdP/dt), heart rate (HR); the extract restored the level of catalase (CAT), glutathione peroxidase (GPx), GSH and SOD, decreased leakage of creatine phosphokinase‐MB (CK‐MB) isoenzyme of and LDH, reduced lipid peroxidation in the heart showing a protection effect against ISP‐induced myocardial infarction.155