Oxygen demand and collateral vessels of the heart. Factors influencing the severity of myocardial ischaemic injury after experimental coronary artery occlusion.

Epicardial electrocardiographic maps were used to assess the effect of heart rate, myocardial contractility, and oxygen need on the severity of myocardial ischaemic injury after acute coronary artery occlusion in dogs. The experimental data indicate statistically significant dependence of the severity of ischaemia on heart rate, contractility, and oxygen need of the heart. These dependences are highly influenced by the spontaneous collateral vessels of the heart.