Carbon monoxide poisoning at a lowered myocardial adaptation capacity: animal ECG models

Two animal models for testing foreign substances for the hypoxic type of cardiotoxicity proved to be valid and reproducible: i.e. decreased reserve capacity of the heart in rats recovered from the calciferol cardiopathy and increased heart work provoked by isoproterenol (5 mg/kg i.p.). In both cases obvious hypoxic ECG changes appeared at lower levels of exposure to carbon monoxide (500 ppm, 572 mg.m-3) and carboxyhemoglobin (18%), when compared with nonpretreated animals. The models have shown, that injured or overloaded heart displays a substantially increased sensitivity to CO poisoning.