Coronary disease, also called coronary artery disease (CAD), is a condition where the arteries supplying blood to your heart become narrowed or blocked by a buildup of fatty deposits called plaque. It is the most common type of heart disease in the United States, affecting about 1 in 20 adults age 20 and older, and it killed 371,506 people in 2022.
How Plaque Builds Up in Your Arteries
Coronary disease develops gradually, often over decades. It starts when the inner lining of a coronary artery gets damaged by risk factors like high cholesterol, high blood pressure, or smoking. Once that lining is irritated, it becomes sticky, attracting white blood cells from the bloodstream. Those immune cells burrow into the artery wall, triggering inflammation.
At the same time, cholesterol particles (specifically LDL, the “bad” cholesterol) seep into the artery wall and get trapped there. Once stuck, these particles undergo chemical changes that make the inflammation worse. Smooth muscle cells migrate into the area and start building a fibrous cap over the growing deposit. Beneath that cap, fat and dead cells accumulate into what’s called a necrotic core. This entire structure is an atherosclerotic plaque.
A plaque can grow slowly for years, gradually narrowing the artery and reducing blood flow. Or its fibrous cap can crack open suddenly, causing a blood clot to form on the spot. That clot can partially or completely block the artery in minutes, which is what triggers a heart attack.
Symptoms to Recognize
Many people with coronary disease have no symptoms at all for years. For some, the first sign is a heart attack. When symptoms do appear, the most common one is angina, a pressure, squeezing, or tightness in the chest. Angina comes in two forms, and the difference between them matters.
Stable angina follows a predictable pattern that has been consistent for at least two months. It typically shows up during physical exertion or emotional stress, lasts a few minutes, and goes away with rest. Unstable angina is more dangerous. It can strike without any physical trigger, lasts longer, feels more intense, and does not reliably go away with rest. Unstable angina is treated as a medical emergency because it often signals that a plaque has ruptured or a clot is forming.
Other symptoms can include shortness of breath, fatigue during routine activities, pain radiating to the jaw, neck, shoulder, or arm, and nausea or lightheadedness. Women are more likely than men to experience these less typical symptoms without the classic chest pressure.
Who Is Most at Risk
Nearly half of adults in the United States have at least one of three key risk factors for coronary disease: high blood pressure, high cholesterol, or smoking. Those are all modifiable, meaning you can change them. Other modifiable risks include physical inactivity, diabetes, obesity, excessive alcohol intake, chronic stress, poor sleep, and unhealthy eating patterns high in saturated fat and refined carbohydrates.
Some risk factors are outside your control. For men, the risk starts climbing significantly around age 45. For women, it rises more sharply around age 55, after menopause reduces the protective effects of estrogen. A family history of early heart disease is also important, especially if a father or brother was diagnosed before 55, or a mother or sister before 65. People of South Asian ancestry face a higher risk of developing coronary disease and its serious complications.
Environmental and workplace factors also play a role. Exposure to air pollution (including wildfire smoke), working more than 55 hours a week, long or irregular night shifts, and prolonged sitting all contribute to higher risk. These factors don’t get as much attention as cholesterol or blood pressure, but they add up over time.
How Coronary Disease Is Diagnosed
Doctors use a combination of tools depending on how likely it is that you have significant blockages. The process often starts with an electrocardiogram (EKG), which records the heart’s electrical activity, and a stress test, where your heart is monitored while you exercise or receive a medication that mimics the effects of exercise.
If those initial tests suggest a problem, imaging provides a closer look. Cardiac CT angiography (CCTA) is a noninvasive option: a contrast dye is injected into a vein in your arm, and a CT scanner takes rapid images that are combined into a detailed 3D picture of your coronary arteries. No catheter is needed, making it a lower-risk test for people at moderate risk of blockages.
For people at higher risk, invasive coronary angiography may be more appropriate. This involves threading a thin catheter through an artery in your leg or arm up to the heart. The advantage is that if doctors find a severe blockage, they can treat it during the same procedure by placing a stent, a tiny wire mesh tube that props the artery open.
Coronary Calcium Scoring
A coronary artery calcium (CAC) scan is a specialized CT scan that detects calcified plaque in the artery walls. It’s particularly useful for people whose risk level is uncertain. Guidelines generally recommend considering it starting around age 45, though it may be appropriate for younger adults who have multiple major risk factors or a family history of premature heart disease. A score of zero suggests very low near-term risk and may allow some people to safely defer cholesterol-lowering medication.
Treatment Options
Treatment depends on how severe the disease is and what symptoms you’re experiencing. For most people, the foundation is a combination of lifestyle changes and medications.
Cholesterol-lowering medications (statins) slow plaque buildup and can stabilize existing plaques so they’re less likely to rupture. Blood pressure medications reduce the workload on your heart. Low-dose aspirin (75 to 100 milligrams daily) acts as a blood thinner, and for people at higher risk of clots, such as those who have had a stent placed or a heart attack, a second anti-clotting medication is often added.
When medications and lifestyle changes aren’t enough, two main procedures can restore blood flow. Percutaneous coronary intervention (PCI), commonly called angioplasty with stenting, opens a blocked artery with a balloon and holds it open with a stent. This is typically used when one or two arteries are blocked. Coronary artery bypass grafting (CABG) is a surgical option where a blood vessel from another part of your body is used to reroute blood around the blocked section. It’s generally recommended when the main left coronary artery is significantly blocked or when multiple arteries are diseased and the anatomy is complex. The choice between the two is individualized, often made by a multidisciplinary heart team weighing factors like which arteries are involved, how severe the blockages are, and your overall health.
What Happens Without Treatment
Left unmanaged, coronary disease gets worse. Plaque continues to build, arteries narrow further, and the heart muscle gradually weakens from chronic reduced blood flow. Over time, this can lead to heart failure, where the heart can no longer pump blood effectively enough to meet the body’s needs. Damaged heart tissue can also develop abnormal electrical rhythms (arrhythmias), some of which are life-threatening.
The most acute danger is a heart attack. When a plaque ruptures and a clot blocks an artery, the section of heart muscle fed by that artery begins to die within minutes. How much muscle is lost depends on how quickly blood flow is restored. This is why recognizing symptoms early and managing risk factors matters so much: a large portion of heart attacks occur in people who didn’t know they had coronary disease.
Reducing Your Risk
The American Heart Association recommends keeping saturated fat below 6% of total daily calories. On a typical 2,000-calorie diet, that means no more than about 13 grams per day, roughly the amount in a couple of tablespoons of butter. Replacing saturated fats with unsaturated fats from sources like olive oil, nuts, and fish makes a measurable difference in cholesterol levels.
Beyond diet, regular physical activity, maintaining a healthy weight, not smoking, limiting alcohol, managing stress, and getting enough quality sleep all lower risk. If you already have high blood pressure, high cholesterol, or diabetes, keeping those conditions well controlled is one of the most effective things you can do to slow or prevent coronary disease from progressing.