Desenvolupament de la microcirculació coronària: remodelació i angiogènesi. Influència de l'edat en el cor sa i en presènci a de patologia

Collateral circulation may play a role when the main vascular channels become stenosed and occluded and the tissue be comespotentially ischemic. Recruitment, enlargement and functionation of the pre-formed channels or new vessels growth (angiogenesis) appears to take place when no prior vascular channels exist. This support the importance of collateral circulation in preserving myocardial funtion after infarction or angor pectoris. Experimental studies show that the survival rate after a gradual coronary occlusion depends on the existence of a rich pre-formed anastomotic network that follows a growth process for getting used to the new haemodynamic situation. This study will be carried out in a series of normal and diseased human hearts. Microvascular architecture will be studied by scanning electron microscopy of corrosion casts and by morphometry (average capillary density and heteroge