[Biometric and histological study of human, porcine and sheep internal thoracic arteries (reflections on their use in revascularization of arteries of less than four millimetres diameter)]. / Etude biométrique et histologique comparative des artères thoraciques internes de l'homme, du porc et du mouton (application en chirurgie de revascularisation des artères de moins de quatre millimètres de diamètre).

In order to enhance the knowledge of the internal thoracic arteries of pig, sheep, and man, allowing to constitute a fundamental basis as for the current and later applications in the interventions in surgery of revascularization of the arteries of less than four millimetre of diameter, a biometric and histological comparative study of these arteries was carried out. Forty human corpses, 27 men and 13 women (mean age 75+/-6 years) were dissected, alike with three pigs respectively weighing 80 kg, 80 kg and 84 kg and four sheep weighing 70 kg each. The left and right internal thoracic arteries were harvested: exposure over the entire length and remote dissection before excision. At the same time their internal lengths and gauges were measured. The internal thoracic artery (ITA) of human has an average useful length of 18 cm and an average internal gauge close to 1.5 mm. ITA of the pig has an average length of 27 cm and an average internal gauge close to 2.8 mm. The ITA of the sheep has an average length of 18 cm with an average internal gauge close to 1 mm. The porcine Internal Thoracic Artery is an elastic artery like its human counterpart. Many elastic fibres and few smooth muscle cells are present in the media. On the other hand, the internal thoracic artery of the sheep has a mixed structure. Its media contains more smooth muscle cells than elastic fibres.