Coronary artery disease (CAD) is the most common form of heart disease and the leading cause of death worldwide. It develops when the arteries that supply blood to your heart muscle become narrowed or blocked by a buildup of plaque. Understanding CAD is the first step toward preventing heart attacks and living well with this condition.
Your heart is a muscle that needs a constant supply of oxygen-rich blood to function. This blood is delivered through the coronary arteries — a network of vessels that wrap around the outside of the heart. Coronary artery disease develops when atherosclerosis — a gradual buildup of cholesterol, fat, calcium, and other substances (collectively called "plaque") — narrows these arteries over time.
As plaque accumulates, less blood can flow to the heart muscle. In stable disease, this may cause symptoms only during exertion. But if a plaque ruptures suddenly and a blood clot forms, it can completely block the artery — this is a heart attack (myocardial infarction).
CAD develops over decades and is influenced by both modifiable and non-modifiable risk factors. The major modifiable risk factors include high blood pressure, high cholesterol (particularly elevated LDL, or "bad cholesterol"), diabetes, smoking, obesity, physical inactivity, and chronic stress. Non-modifiable factors include age, male sex (though women's risk increases after menopause), and a family history of premature coronary disease.
The good news is that many of these risk factors are addressable through lifestyle changes and medications, even in patients who have already been diagnosed with CAD.
CAD can present in several ways depending on the degree of blockage and whether a heart attack is occurring.
Chest discomfort (pressure, tightness, or heaviness) that occurs predictably with physical activity or emotional stress and resolves with rest. Some patients experience the discomfort in the jaw, shoulder, arm, or back rather than the chest. Shortness of breath with exertion is another common presentation, particularly in women and patients with diabetes.
When a plaque ruptures and a clot forms, symptoms are more severe and persistent. These include intense chest pressure lasting more than a few minutes, pain radiating to the arm, jaw, or back, shortness of breath, sweating, nausea, or lightheadedness.
If you or someone you know experiences persistent chest pain, pressure, or tightness — especially with sweating, shortness of breath, or pain radiating to the arm or jaw — call 911. Time is critical in a heart attack. Do not drive yourself to the hospital.
Diagnosis typically begins with a thorough history and physical exam, followed by testing. Common diagnostic approaches include electrocardiogram (ECG) to detect electrical changes in the heart, stress testing (exercise or pharmacologic) to assess blood flow during exertion, echocardiography to evaluate heart function, coronary CT angiography for non-invasive imaging of the coronary arteries, and cardiac catheterization (coronary angiography) — the gold standard — where a thin catheter is threaded into the coronary arteries and contrast dye is used to visualize blockages in real time.
Treatment for CAD is tailored to the severity of disease, the number and location of blockages, symptoms, and overall health. It generally falls into three categories:
This is the foundation of CAD management for all patients, regardless of whether a procedure is performed. It includes risk factor modification (smoking cessation, exercise, diet, weight management), medications to lower cholesterol (statins), control blood pressure, manage diabetes, and prevent blood clots (aspirin and other antiplatelet drugs). For many patients with stable CAD, optimal medical therapy can be as effective as procedures at preventing future heart attacks.
PCI — commonly called "stenting" or "angioplasty" — is a catheter-based procedure to open blocked coronary arteries. A cardiologist inserts a thin wire and balloon through an artery in the wrist or groin, navigates to the blockage, inflates the balloon to open it, and deploys a small metal mesh tube (stent) to keep the artery open. Modern drug-eluting stents are coated with medication to prevent re-narrowing.
PCI is the primary treatment during an acute heart attack (emergent PCI) and is also used electively for patients with significant blockages causing symptoms despite medications.
Bypass surgery is an open-heart operation in which a cardiac surgeon uses blood vessels harvested from the chest wall, leg, or arm to create new routes (grafts) around blocked coronary arteries. CABG is typically recommended for patients with complex multi-vessel disease, left main coronary artery disease, or diabetes with extensive blockages — situations where surgery has been shown to improve long-term outcomes compared to stenting.
A minimally invasive procedure performed through the wrist or groin.
An open-heart operation to bypass blocked arteries using grafts.
The decision between PCI and CABG is individualized. Your heart team considers the number, location, and complexity of blockages; your overall health and surgical risk; diabetes status; heart function; and your own preferences and goals. For some patients, either option may be appropriate — this is where shared decision-making with your cardiologist and surgeon is most important.
Coronary artery disease is a chronic condition that requires lifelong management. Even after a successful stent or bypass, the underlying process of atherosclerosis continues if risk factors are not addressed. Patients who commit to cardiac rehabilitation, take prescribed medications consistently, maintain a heart-healthy diet, exercise regularly, and see their cardiologist for follow-up can significantly reduce the risk of future events and live full, active lives.