Fatal derecruitment of occluded left anterior descending collaterals after left circumflex revascularization.

Coronary arteries are not definitely functionally terminal arteries, as previously thought; indeed, they are linked and interconnected by a rich network of collaterals. Chronic total occlusions (CTOs) represent a subset of frequent lesions encountered in everyday catheterization laboratory practice, generally associated with a developed system of collateral connections. These latter have the capacity to prevent myocardial necrosis and may even uphold metabolic supply to the ischemic territory to maintain its contractile capacity. Authors have reported a rapid and progressive reduction of collateral function and their decline after antegrade flow restoration, resulting in higher myocardial susceptibility to ischemia in the CTO territory. Here, we report the case of a fatal derecruitment of collaterals for a left anterior descending CTO not reopened, after left circumflex subocclusion revascularization.