Glagov Phenomenon

Glagov phenomenon

Glagov phenomenon is the positive remodeling of arteries described by Seymour Glagov in 1987 [1]. By meticulous serial sectioning of left main coronary arteries in necropsy specimens, Glagov observed that the arterial size is proportional to the plaque burden. The process of enlargement of the artery to accommodate the plaque and maintain the lumen has been called as the Glagov phenomenon. It also known as compensatory enlargement or positive remodeling of the artery.

In the their histological study of 136 left main coronary arteries, they found that in the initial stages, the coronary plaque does not compromise the lumen as the plaque grows abluminally, away from the lumen. They noted that the lumen did not decrease for plaque diameter from zero to 40%, beyond which the lumen starts getting compromised. This preservation of a nearly normal luminal cross sectional area despite a large plaque, should be considered while evaluating coronary atherosclerosis by coronary angiogram which is typically a ‘luminogram’.

Although the phenomenon was initially described for arterial remodeling in response to the growth of atherosclerotic plaques, later studies indicate that blood flow properties influence remodeling after angioplasty, in hypertension and in flow diversion [2].

References

1. S Glagov, E Weisenberg, C K Zarins, R Stankunavicius, G J Kolettis. Compensatory Enlargement of Human Atherosclerotic Coronary Arteries. N Engl J Med
   . 1987 May 28;316(22):1371-5.
2. Vyacheslav A Korshunov, Stephen M Schwartz, Bradford C Berk. Vascular Remodeling: Hemodynamic and Biochemical Mechanisms Underlying Glagov’s Phenomenon. Arterioscler Thromb Vasc Biol
   . 2007 Aug;27(8):1722-8.