Figure 1

Schematic drawing of the coronary artery circulation with (left panel) and without (right panel) interarterial anastomoses between the right coronary artery and the occluded left anterior descending artery (LAD; occluded beyond the third diagonal branch). The gray area indicates the area at risk for myocardial infarction in case of the LAD occlusion and in the absence of collaterals (corresponding to the infarct size in the example on the right side). (Illustration by Anne Wadmore, Medical Illustrations Ltd, London, UK).