Angina Pectoris – Top USMLE Diseases

Coronary heart disease (CHD), or ischemic heart disease, describes a situation in which an inadequate supply of blood to the myocardium exists due to a stenosis of the coronary arteries, typically from atherosclerosis. The myocardium becomes ischemic when oxygen supply does not meet oxygen demand. Diagnosis is based on history and ECG findings; cardiac stress tests and catheterizations may also be needed. Treatment is primarily based on reducing the heart's oxygen demand and increasing the delivery of oxygen.

An incongruous alteration in the flow of blood in the form of steal syndromes is a well-known complication of coronary artery bypass grafting (CABG). It might be discovered incidentally, that is during an ultrasonographic or angiographic examination performed for any other indications, or during the clinical examination, finding of reduced blood pressure or unilateral upper-limb pulse. Treatment mostly comprises of open subclavian artery revascularization, normally via carotid-subclavian bypass or subclavian artery transposition, and new less invasive options which are endovascular intervention with recanalization, angioplasty with stenting if needed.

The main symptom of coronary heart disease is angina pectoris, which can be divided into a stable and an unstable form.

Acute coronary syndrome is defined as acute anginal pain because of partial or total occlusion of one or more coronary arteries due to advanced coronary heart disease. Three clinical entities can be identified: Unstable angina (UA), Non-ST-segment elevation MI (NSTEMI) and ST-segment elevation MI. They can be differentiated based on the ECG changes and the cardiac markers. ACS is initially managed medically with a well-known algorithm. Revascularization of the coronaries either by cardiac catheterization or surgery should be planned as soon as possible.

Myocardial infarction is one of the most common causes of death in industrialized countries and requires immediate intervention, according to the principle “Time is Muscle”. 40 % of all patients die before their first post-infarction day, and 50 % die in the first four weeks. Early detection and swift action are of crucial significance, especially in the case of ST-segment elevation myocardial infarction.