Doctor's Notes on Heart Disease
Heart disease (cardiac disease) describes any disorder that affects the heart. It is not the same as cardiovascular disease, which is any disease of the heart blood vessels.
Some people with heart disease may have no apparent symptoms. Arteries may be blocked 50% or more without causing any symptoms. When symptoms of heart disease do occur they may include
- palpitations (a sensation of rapid or very strong heart beats in your chest),
- dizziness,
- light-headedness,
- fainting,
- weakness on exertion or at rest,
- irregular heartbeat (arrhythmia), and
- chest pain on exertion (angina pectoris).
Sudden cardiac arrest can occur when the heart suddenly stops beating effectively. This condition can be fatal. Cardiac arrest typically occurs in people who have had previous heart attacks, but it may occur as the first symptom of heart disease.
Heart Disease : Test Your Medical IQ Quiz

In the U.S., 1 in every 4 deaths is caused by heart disease.
See AnswerREFERENCE:
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.