Curriculum · Cardiovascular and Hypertension
Chronic stable angina
What it is
Stable angina pectoris is due to fixed atherosclerotic lesions that narrow the major coronary arteries. Coronary ischemia is due to an imbalance between blood supply and oxygen demand, leading to inadequate perfusion, and stable angina occurs when oxygen demand exceeds available blood supply. Stable angina occurs when the myocardium becomes ischemic. Ischemic heart disease may be clinically silent and asymptomatic, or symptomatic. Symptomatic disease is stable angina or one of the acute coronary syndromes: unstable angina, non ST-segment elevation MI, and ST-segment elevation MI.
Causes and risk
The fixed lesions are atherosclerotic plaque in the intima and media of the coronary artery. Progression of atherosclerotic plaque, a ruptured plaque and thrombosis formation are what carry ischemic heart disease on to the acute coronary syndromes. Risk factor modification is part of treatment, and the risk factors named for it are HTN, DM, lipids and smoking.
How it presents
Typical anginal chest pain is substernal, worse with exertion, and better with rest or nitro-glycerin. All the three must be there or it is atypical angina. The pain is typically a substernal pressure lasting 5–15 minutes, improved with rest and GTN. The ECG change during an attack is ST depression.