THE ABSENCE OF LYMPHATICS IN NORMAL AND ATHEROSCLEROTIC CORONARY ARTERIES IN MAN: A MORPHOLOGIC STUDY

It has been suggested by various investigatorsthat the impairment of lymphaticdrainage from the coronary arteries may playa role in predisposition to coronary atherosclerosis,the pathogenesis of which iscertainly multifactorial. In our study, nolymphatic vessels were found in the walls ofthe coronary arteries (adventitia, media andintima) in 51 human hearts from patientsranging in ages from 3 months to 83 yearswith normal coronary arteries, coronaryatherosclerosis, and cardiomyopathy.Visualized lymphatics were located solely inthe periadventitial area, and these lymphaticswere more irregular in hearts from olderpersons. With injection, histology, andelectronmicroscopy methods we could notdetect penetration of lymphatics into the wallof coronary trunks in normal as wellatherosclerotic arteries. In all coronaryarteries studied, and particularly in theatherosclerotic lesions, blood vasa vasorumcould be visualized. In the atheroscleroticareas, vasa vasorum (angiogenesis) could beseen penetrating into the media and intima.Many of the thin-walled vasa vasorum couldeasily be mistaken for lymphatics. Theabsence of lymphatics draining the epicardialcoronary arteries may be a predisposing factorto coronary atherosclerosis.