More than cholesterol: the complexity of coronary artery disease
Ijem, J.; Granlie, C.
South Dakota Journal of Medicine 53(11): 489-491
2000
ISSN/ISBN: 0038-3317 PMID: 11098718 Document Number: 513552
There have been many recent articles published that emphasize the fact that cholesterol deposits are only one of many mechanisms through which acute coronary artery disease develops. Recently, a meta-analysis shows that only 14% of acute coronary events occur in stenotic lesions in coronary arteries that are greater than 70% occluded. The majority of acute coronary events (68%) occur in coronary arteries that have less than 50% stenotic lesions. The acute coronary syndrome is a very complex and unpredictable disease. Recent information now points to the endothelium as a modulating factor in the pathogenesis of coronary artery disease through the production of nitric oxide and angiotensin-II which maintain the homeostatic environment influencing the progression of coronary artery disease. With dysfunctional endothelium there seems to be an imbalance in terms of angiotensin production with regards to the nitric oxide production. This imbalance tends to promote coronary artery disease in individuals who have multiple risk factors. Furthermore, it has been suggested that certain inflammatory compounds are produced in a very dysfunctional endothelium, thereby propagating or leading to acute coronary syndromes. Specifically, this includes C-reactive protein which promotes chronic inflammation at various sites. There are also other acute phase reactants, such as fibrinogen, which may play a role in atherogenesis. Certain statin drugs, as they are called, tend to ameliorate the levels of the above acute phase reactants, while other statins do not. This reduction of coronary events by statins is independent of the LDL lowering benefits from statin drugs. This article delineates some of the beneficial effects of the different statin agents and points out that all statins are not equal in terms of their known lipid beneficial effects. For the practicing physician, choosing a particular statin agent is important. Some have more drug/drug interaction potential as compared with the others because of their inability to be metabolized through the cytochrome P450 system. There are also some, because of their lipophilic and hydrophilic nature, that tend to enter cells more readily than other statin agents. The effects conferred by these subtle differences among the currently available statins tend to be beneficial in patients with low to moderate levels of LDL cholesterol.