The Capillaries in Ischemic Border Zone: Origin And Role in Myocardial Infarction and Heart Failure

It is a general believe that a blocked artery and its capillary are the main factor to determine myocardial infarction (MI) size and cardiac dysfunction. We have be plagued by the problem in repairing and regeneration of MI for many decades. How to improve the infarcted myocardium? By relieving the obstruction in coronary artery or promoting the angiogenesis of capillaries in the ischemic border zone? How to regrow the deteriorated capillary? From where? It is incredible to image the role of nearby non-ligated vessels in myocardial death and cardiac depression. In the present study, we show evidences that ischemic MI are not determined solely by the occluded artery, but also involved the nearby non-occluded artery, especially its capillaries that contributed nearly one-third effort to the MI. The mechanism is unclear yet, but this phenomenon is very interesting, offers a novel perspective to study heart failure. Arterial resistance to ischemia is a new object in heart failure research. It is unclear why some arterial vessel could survive in transmural MI, more interestingly it is unknown if capillaries could be regenerated from the residue arterial vessel in MI. The role of capillary both in ischemic artery and nearby non-ischemic branch in MI development is an amazing challenge. It is unknown why occlusion of left branch of LCA could degenerate capillaries on right branch of LCA. Inflammation probably plays a role in this phenomenon, but the knowledge of its mechanism is totally lacking even it indicates a potential path to new treatment strategy of ischemic heart disease.