Snapshot A 70-year-old man presents to his primary care physician with recurrent, intermittent, sudden-onset chest pain and shortness of breath. He reports that he often tires easily climbing the stairs. Initially, he experienced chest pain with activity, but now it occurs throughout the day. Medical history is significant for hypertension and type II diabetes. An electrocardiogram demonstrates mild ST-segment depressions in V1-V2. Cardiac troponins are not elevated. (Unstable angina) Introduction Clinical definition substernal chest discomfort secondary to myocardial ischemia; however, myocyte necrosis is not present note that patient will likely report discomfort rather than pain Types of AnginaTypesPathologyClinical PresentationCommentsStable anginaTypically secondary to atherosclerosisthis impairs coronary perfusion in the setting of increased cardiac demand (e.g., exertion)Chest pain that develops with exertion but relieves with rest or nitroglycerinElectrocardiogrammay demonstrate ST segment depressionsUnstable anginaIncomplete coronary artery occlusion by a thrombusindicative of a ruptured plaque with subsequent clot formationChest pain that persists whether with decreasing physical activity or restElectrocardiogrammay demonstrate ST segment depressions or T wave inversionsPrinzmetal anginaCoronary artery spasmsChest discomfort unrelated to physical activity and is episodicTriggerscocainealcoholtriptansElectrocardiogramappears similar to a STEMImay demonstrate ST segment elevations with reciprocal ST depressionsTreatmentcalcium channel blockerssmoking cessationnitrates Epidemiology Risk factors smoking atherosclerosis poor dietary habits Etiology Pathogenesis background myocardial ischemia occurs when the heart's demand for oxygen exceeds oxygen supply login to view 11 more bullets pathology myocardial ischemia leads to acidosis, a ↓ ATP supply, and the release of chemical substances (e.g., adenosine) login to view 4 more bullets Imaging Initial EKG Cardiac biomarkers: troponin, CK, and/or CK-MB CXR Cardiac catheterization for definitive diagnosis for high-risk patients locate and assess severity of the lesion(s) +/- treatment (i.e., stent) Low risk patients with negative work-up can be discharged with reassurance young (<50 years of age), female, active, non-smoker, chest pain not associated with exertion Studies Stress-testing to evaluate simultaneously with EKG, echo, and radionuclide perfusion studies for suspected stable angina, initial exercise stress EKG +/- echo is indicated in patients with no contraindications to exercise login to view 2 more bullets for patients with intermediate-risk (i.e., chest pain that develops with exertion, but is relieved with rest or nitroglycerin, CAD risk factors) all antianginal medications (beta-blockers, nitrates, calcium channel blockers) should be held for 48 hours before a stress test for pharmacological stress tests using adenosine or regadenoson, use of dipyridamole should be held for 48 hours and intake of caffeine held for 12 hours to minimize false negative findings of ischemia