The heart muscle needs a constant supply of oxygen-rich blood. The coronary arteries, which branch off the aorta just after it leaves the heart, deliver this blood. Coronary artery disease that narrows one or more of these arteries can block blood flow, causing chest pain (angina) or an acute coronary syndrome (see also Overview of Coronary Artery Disease).
In an acute coronary syndrome, sudden blockage in a coronary artery greatly reduces or cuts off the blood supply to an area of the heart muscle (myocardium). The lack of blood supply to any tissue is termed ischemia. If the supply is greatly reduced or cut off for more than a few minutes, heart tissue dies. A heart attack, also termed myocardial infarction (MI), is death of heart tissue due to ischemia.
There are many different reasons doctors give medications to people with coronary artery disease:
To relieve chest pain by reducing the heart's workload and widening arteries (usually nitrates)
To prevent and reverse coronary artery narrowing from atherosclerosis (angiotensin-converting enzyme [ACE] inhibitors, angiotensin II receptor blockers [ARBs], statins, and antiplatelet medications)
To open a blocked artery (clot-dissolving medications, anticoagulants)
Often, oxygen is given through nasal prongs or a face mask. Providing more oxygen to the heart can help keep heart tissue damage to a minimum.
Nitrates
Morphine
antiplatelet medications and reduce their effectiveness and may slightly increase the risk of death.
Beta-blockers
Because decreasing the heart’s workload also helps limit tissue damage, a beta-blocker is usually given to slow the heart rate. Slowing the rate enables the heart to work less hard and reduces the area of damaged tissue.
Calcium channel blockers
Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers
Angiotensin-converting enzyme (ACE) inhibitors and (ARBs) can reduce heart enlargement and increase the chance of survival for many people. Therefore, these medications are usually given in the first few days after a heart attack and prescribed indefinitely.
Statins
Statins have long been used to help prevent coronary artery disease, but they also have short-term benefit for people with an acute coronary syndrome. Doctors give a statin to people who are not already taking one.
Antiplatelet medications
aspirin
Clot-dissolving medications
Clot-dissolving medications (thrombolytic medications) are given intravenously to open the arteries if percutaneous coronary interventions cannot be done within 90 minutes after the person arrives at the hospital.
Anticoagulants
Ranolazine and ivabradine
PCSK-9 inhibitors
hyperlipidemia, including familial hypercholesterolemia. They can be particularly useful for people who have difficulty tolerating the side effects of other medications that lower cholesterol levels.