Coronary Artery diseases

Coronary Artery Diseases (CAD)
? Most commonly defined as a >50% luminal Stenosis of any epicardial coronary artery.
? CAD (leading cause of M & M in Western Society.
? Prevalence of CAD in the US (7.6% - 2006).
? CAD (35.3%) U.S. deaths in 2005.
Etiology
? luminal obstruction by atheromatous plaque.
? Congenital coronary abnormalities
? Myocardial bridging
? Vasculitis
? Prior radiation therapy
? Cocaine
? Aortic stenosis
? Hypertrophic cardiomyopathy
? Coronary vasospasm
? Spontaneous coronary dissection
? Syndrome X.
Pathophysiology
? CAD (stable angina, Acute Coronary syndrome (ACS), CHF, sudden cardiac death, and silent ischemia.
? Stable angina (most often results from fixed coronary lesions that produce a mismatch between myocardial oxygen supply and demand. This mismatch is accentuated by increasing cardiac workload).
? ACS (clinical presentations ranging from UA to ST-segment elevation MI (STEMI)- Acute thrombosis of a coronary artery at the site of atheromatous plaque rupture or ulceration.
? Anginal symptoms usually develop when a fixed stenosis reaches ? 70%. In the setting of increased myocardial demand or diminished oxygen supply, the fixed stenosis does not permit adequate distal perfusion and ischemia results, manifesting itself as angina.
Risk Factors
• Hypertension
• DM : 2-4 X. Insulin resistance (Metabolic syndrome).
• Obesity BMI of >25 kg/m2 & >30 kg/m2 .
• Dyslipidemia: ?LDL, ? HDL, and ? TG.
• Family history of premature CAD: 1ST degree male relative with CAD before age 55 or female relative before age 65.
• Tobacco use is associated with a marked increase in risk of CAD. The risk is reversible and smoking cessation restores the risk of CAD to that of a nonsmoker within approximately 15 years
Prevention
? Aspirin
(75 -162 mg/d) in patients at higher risk of CV events (>10% risk of stroke or MI over 10 years). Men 45 -79 & Women 55-79yr
? Regular cardiovascular risk assessment
At age 20 and recurring every 5 years. The Framingham Risk Score .
? Risk factor modification
Tobacco cessation, treatment of hypertension, DM, obesity, &lipid control.
? Initiation of Statin therapy (CRP).
? Current exercise guidelines