Journal d'histologie moléculaire et de physiologie médicale

Histological Characterization of the Internal Thoracic Artery as Preferred Conduit for Coronary Bypass

Abstract

Antonio Manenti, Luca Roncati, Luca Caprili, and Corrado Fedeli

Background

The Internal thoracic artery is today the preferred conduit for coronary bypass. This correlates with the histological characteristics of this artery. This particular topic was considered worthy of morphological researches, by the modern immune-histo-chemical techniques.

Methods

Histological researches, performed also with immune-histo-chemical techniques were performed on surgical specimens of internal thoracic artery of patients submitted to coronary surgery.

Results

Internal thoracic artery is a small-medium vessel with prevalent characteristics of elastic vessel, especially in its proximal part. It demonstrates a particular resistance to atherosclerosis, also in elderly. A possible elastotic degeneration, often secondary to age, can interests the elastic fibers of the internal membrane and of the tunica media. These degenerative lesions are repaired through a remodeling process. In this way, new smooth muscle-like cells are formed, which appear morphologically and functionally different from the vascular smooth muscle cells.

Conclusions

The internal thoracic artery, also when remodeled preserves its elastic capacity and resistance to atherosclerosis, ensuring good functional characteristics with a reactivity normal to vasodilators, but decreased to vasoconstrictors.