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Improvement of myocardial ischaemia by lipid lowering drugs.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Tzivoni, Dan Klein, Jeffrey C. |
| Copyright Year | 1998 |
| Abstract | Coronary artery disease is characterized by the presence of atherosclerotic plaques that may limit or obstruct coronary flow, and by abnormal endothelial function, which may reduce luminal diameter either at rest or during stress conditions. The role of endothelial dysfunction in the clinical expression and progression of coronary artery disease is not very well defined. As regression of atherosclerotic plaques cannot be achieved in most coronary artery disease patients, research has focused on the potential role of risk factor modification to improve endothelial function, retard progression of coronary artery disease and alleviate myocardial ischaemia and anginal symptoms. Soft coronary atherosclerotic plaques with a high concentration of cholesterol-esters are highly likely to undergo disruption. These cholesterol rich ‘active plaques’ are also characterized by a high concentration of monocytes and macrophages. Atherectomy specimens obtained from patients with acute coronary syndromes (mainly unstable angina) revealed a higher concentration of macrophages compared to specimens obtained from patients with stable angina. Similar findings were reported from autopsy studies. The macrophage releases metalloproteins such as interstitial collagenase, gelatinase and stromalysin, which can accelerate the breakdown of extracellular matrix and promote plaque disruption. Reduction of cholesterol may not only reduce the lipid content of the plaque, but can also reduce the accumulation of monocytes and macrophages, thereby contributing to transformation of the ‘active plaque’ into a less active or quiescent plaque. In addition, lowering of LDL levels increases nitric oxide formation, which reduces platelet adhesion and thrombus formation. In coronary segments with atherosclerotic plaque, local secretion of endothelium-derived relaxing factor is reduced and release of endothelin-1 is increased leading to an exaggerated vasoconstrictive response in the areas of atherosclerotic plaque. This excessive vasoconstriction probably plays a significant role not only during unstable angina, but also in the many daily occurrences of ischaemic episodes in which increased coronary tone plays an important role. It appears that the reduced risk of acute ischaemic events is the result of a reduced tendency to exaggerate local vasoconstriction, secondary to lipid lowering. Improved vasomotor tone may improve daily occurrences of ischaemia and its main clinical expression, angina pectoris. |
| Starting Page | 1 |
| Ending Page | 6 |
| Page Count | 6 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | https://oup.silverchair-cdn.com/oup/backfile/Content_public/Journal/eurheartj/19/2/10.1053_euhj.1997.0724/1/230.pdf?Expires=1492394041&Key-Pair-Id=APKAIUCZBIA4LVPAVW3Q&Signature=R-LclzyKT8r0JeEyj~lIPd09DuEWEwU1wCDy~ZWirNBdb6aBrrFwQl4UDB9xgU-J2TapA2DUKoxqZ2gQyScDId6G0H6kDSjDzugstkvVD84XKugLmyD5q7Lqst1P8APRvGu8mov2RGaluNyvVyNLmK-B-iYokg3-Y5fe1zbtaQy3SYbKsXbSHn-JYy21yJtDAT0rZccyC-FUqYIlIzSPoVsFMWoMGYNQqv4T9mGNlk2zulvp8KZDRKkOSnSJuFjwg4ZWTlxecqSEDIhlA3nagM5X5-JDV0R5rbsK9Z95JUHfUCykb9ABpJSMSHDtTcMkhGIipvR~u9KQm~bz-gfdWw__ |
| PubMed reference number | 9519315v1 |
| Volume Number | 19 |
| Issue Number | 2 |
| Journal | European heart journal |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Angina Pectoris Arteriopathic disease Atherosclerosis Blood Platelets COLLAGENASE Catabolism Cholesterol Contribution Coronary Artery Disease Dental Plaque Diameter (qualifier value) Endothelin-1 Episode of Care Esters Extracellular Matrix Gelatinases Leukemia, Myelocytic, Acute Metalloproteins Myocardial Ischemia Patients Phenobarbital Plaque, Atherosclerotic Senile Plaques Specimen Syndrome Thrombosis Unstable Medical Device Problem Vascular constriction (function) nitric oxide biosynthetic process |
| Content Type | Text |
| Resource Type | Article |
