| Snapshot |
| A 54-year-old man presents to the emergency department 30 minutes after developing crushing sternal chest pain that radiates down the left arm and to the jaw. His symptoms are accompanied by anxiety. Medical history is significant for hypertension, hypercholesterolemia, and type II diabetes mellitus. On physical exam, the patient appears restless and is diaphoretic. An electrocardiogram is performed, which shows ST-segment elevated in leads V1-4. The cardiac catheterization lab is activated and the patient is awaiting stenting after appropriate acute management for acute coronary syndrome. |
| Introduction |
| Definitiona pathological process that causes damage to theaortacerebrovasculaturecoronary arteriesperipheral arteriesEpidemiologyrisk factorsmodifiablehypertensioncigarette smokinghyperlipidemiaespecially hypercholesterolemianonmodifiableagemale genderfamily historygenetic abnormalities (e.g., LDL receptor gene mutations)Pathophysiology backgroundLDL transports cholesterol into peripheral tissues and HDL mobilizes cholesterol from the periphery and into the liver for excretion via bilepathogenesis injury (e.g., smoking, hypertension, and hypercholesterolemia) to the endothelium leads to endothelial dysfunction resulting in increased vessel permeabilitymonocyte adhesion and emigrationmacrophages become activated within the vessel intima and smooth muscles are recruited smooth muscle cells migrate to the intima via FGF and PDGFsmooth muscle cells and macrophages engulf lipids (e.g., LDL), forming foam cells, along with recruitment of T lymphocytes forming a fatty streak smooth muscle cells proliferate and there is deposition of the extracellular matrix, resulting in the fatty streak becoming a fibrofatty atheroma slow forming plaques allow for the formation of collateral circulation locationabdominal aorta > coronary artery > popliteal artery > carotid artery |
| Presentation |
| Symptomsanginaif > 75% obstruction myocardial demand ischemia type of stable angina where individuals with known atherosclerotic coronary disease experience relative myocardial ischemia during episodes of high metabolic demandsubendocardial vessels are susceptible to ischemia during systole due to high resistance and systolic back flow from endocardial to epicardial vessels left ventricular subendocardial muscle most likely due to left coronary vessel systolic compression supply/demand mismatch can cause anginal pain and ischemic changes on EKGclaudicationcan be asymptomatic |
| Complications |
| Aneurysms Myocardial infarctionIschemic stroke Peripheral vascular disease Atheromatous plaque disruption can result in thrombosis thrombus fragments can break off and result in an embolism |