Snap Shot A 67-year-old construction foreman is brought to the emergency department by ambulance after complaining to his coworkers of sudden onset chest tightness and shortness of breath. He has a 45 pack-year smoking history, takes aspirin and simvastatin, and has a BMI of 33. Introduction Definition An imbalance between heart oxygen supply and demand resulting in ischemia Cause Primarily atherosclerotic occlusion of the coronary arteries Types angina pectoris myocardial infarction sudden cardiac death chronic ischemic heart disease myocardial stunning Major risk factors include diabetes mellitus (most important and considered a CAD equivalent) smoking (#1 preventable factor) HTN cholesterol/lipid abnormalities LDL > 160 HDL < 35 family history age >45 (men), age >55 (women) Minor risk factors include obesity lack of estrogens why men have earlier onset elevated homocysteine levels cocaine use amphetamine use Presentation Symptoms range from asymptomatic particularly in older women and diabetics to substernal tightness and/or pain and shortness of breath often diagnosed and characterized as stable angina predictable; presents with consistent amount of exertion patient can achieve relief with rest or nitroglycerin indicative of a stable, flow-limiting plaque unstable angina unpredictable; often presents at period of inactivity defined as any new angina or rapidly worsening stable angina limited improvement with nitroglycerin, and usually recurs soon afterward indicative of a ruptured plaque with subsequent clot-formation in vessel lumen Differential Diagnosis Costochondritis GERD Generalized anxiety/panic attacks Aortic dissection Evaluation Cardiac catheterization for definitive diagnosis locate and assess severity of the lesion(s) CXR to rule out aortic dissection Elevated cardiac biomarkers troponin, CK, and/or CK-MB may be present EKG ST elevation or depression depending on severity of ischemia Q waves Stress-testing to evaluate simultaneously with EKG, echo, and radionuclide perfusion studies Treatment In acute coronary syndrome use "MONA-B" morphine oxygen nitroglycerin aspirin ACE-inhibitors may also use B-blockers, GPIIb/IIIa antagonists and angioplasty Drugs that improve post-MI mortality rates include Aspirin B-blockers ACE-inhibitors ARBs and HMG-CoA reductase inhibitors (statins) NOT calcium channel blockers