Relationship between reduced elasticity of extracardiac vessels and left main stem coronary artery disease

To investigate the elastic properties of medium-size extracardiac arteries and veins between patients with and without left main stem coronary artery disease.

The compliance, distensibility, and incremental elastic modulus (iEmod) of the internal thoracic arteries (n=53), long saphenous veins (n=38), and radial arteries (n=35) from 74 patients undergoing coronary surgery were studied in organ baths. Twenty-four patients had left main stem (LMS) disease and 50 non-LMS coronary disease.

Internal thoracic arteries from patients with LMS presented significantly lower compliance (-17%) and distensibility (-18%) and significantly higher iEmod (19%) than internal thoracic arteries from patients with non-LMS disease. Radial arteries from patients with LMS presented higher iEmod (50%) than radial arteries from patients with non-LMS disease. Furthermore, long saphenous veins from patients with LMS had reduced compliance (-45%), reduced distensibility (-40%) and increased iEmod (34%) compared to those from patients with non-LMS disease.

LMS coronary disease is associated with a significantly reduced elasticity of extracardiac arteries and veins compared to non-LMS coronary disease. This finding suggests that widespread vascular elasticity defects may play a role in the development of LMS disease and be responsible for the higher incidence of early and late cardiovascular morbidity observed in this condition.