Coronary Plaque
Coronary plaque is a buildup of cholesterol, fat, calcium, inflammatory cells, and other materials within the wall of the coronary arteries—the vessels that supply blood to the heart muscle. Plaque is the underlying lesion of coronary artery disease and can range from small, stable deposits to large, unstable lesions that may rupture and cause a heart attack. Modern cardiac imaging—including coronary CT angiography (CCTA) and coronary artery calcium (CAC) scoring—can identify and characterize plaque, often before symptoms develop, helping to guide prevention and treatment.
What is it?
The coronary arteries are the vessels that supply the heart muscle itself with oxygen-rich blood. Coronary plaque is a buildup of fatty material, cholesterol, inflammatory cells, smooth muscle cells, calcium, and other substances within the wall of these arteries. Plaque is the underlying lesion of coronary artery disease and the slow, progressive process by which it forms is called atherosclerosis. Plaque can develop silently over many years before causing any symptoms.
Coronary plaque is generally described by its composition and behavior on imaging. Calcified plaque contains significant calcium deposits and is visible on a coronary artery calcium (CAC) scoring scan. Noncalcified (soft) plaque contains predominantly fatty and fibrous material and is best seen on coronary CT angiography (CCTA); soft plaque is generally considered more biologically active and potentially more prone to rupture than densely calcified plaque. Mixed plaque contains both calcified and noncalcified components. Plaque is also described as obstructive when it significantly narrows the artery (typically more than 50% of the lumen) or non-obstructive when narrowing is less severe; importantly, both obstructive and non-obstructive plaque are clinically important, and many heart attacks actually arise from non-obstructive plaque that ruptures.
The development of coronary plaque is driven by a combination of biological and lifestyle factors. Major risk factors include high LDL cholesterol, high blood pressure, diabetes, smoking, obesity, physical inactivity, unhealthy diet, family history of early coronary disease, increasing age, and certain inflammatory and metabolic conditions. Some plaque features—such as a thin fibrous cap, a large lipid-rich core, positive remodeling of the artery, low attenuation on CT, and “napkin-ring” sign—are associated with higher risk of plaque rupture and acute coronary events. These higher-risk features can sometimes be identified on advanced imaging.
Many people with coronary plaque have no symptoms, particularly when plaque is small or non-obstructive. As plaque grows and reduces blood flow, especially during exertion, patients may develop angina (chest pressure, tightness, or discomfort that occurs with activity or stress and improves with rest), shortness of breath, reduced exercise tolerance, or fatigue. Plaque rupture or erosion can trigger sudden formation of a blood clot, leading to acute coronary syndromes such as unstable angina or heart attack, often with severe and sustained chest pain, shortness of breath, sweating, nausea, lightheadedness, or other emergency symptoms.
Imaging plays a central role in identifying and characterizing coronary plaque. Coronary artery calcium (CAC) scoring uses a low-dose, noncontrast CT scan to detect and quantify calcified plaque, providing a calcium score (often the Agatston score) that is one of the strongest predictors of future cardiovascular events. A CAC score of zero is associated with very low short-term risk, while higher scores generally indicate greater overall plaque burden. Coronary CT angiography (CCTA) uses contrast-enhanced CT to directly visualize the coronary arteries and can assess both calcified and noncalcified plaque, the degree of luminal narrowing, and additional plaque features that influence risk. Stress testing assesses how the heart performs under increased demand and helps identify obstructive disease. Cardiac catheterization with invasive coronary angiography remains the standard for definitive evaluation and is typically used when intervention is anticipated.
Important to Know
The presence of coronary plaque does not necessarily mean immediate problems, but it does represent an opportunity—often early—to take meaningful steps to reduce the risk of heart attack and other complications. The intensity of treatment is generally guided by the amount and type of plaque, the patient’s overall cardiovascular risk, and the presence or absence of symptoms.
Lifestyle measures are foundational and benefit nearly all patients. These include not smoking, regular physical activity, a heart-healthy diet (rich in vegetables, fruits, whole grains, healthy fats, and lean proteins; lower in saturated and trans fats, processed foods, added sugars, and excessive salt), weight management, limited alcohol, stress reduction, good sleep, and treatment of sleep apnea when present.
Medications play a central role for many patients with detected coronary plaque. Statins are particularly important because they lower LDL cholesterol and stabilize plaque, reducing the risk of rupture and cardiovascular events; other lipid-lowering therapies (such as ezetimibe, PCSK9 inhibitors, and newer agents) may be added when more aggressive LDL lowering is needed. Blood pressure control, diabetes management (with cardioprotective agents such as SGLT2 inhibitors and GLP-1 receptor agonists when appropriate), antiplatelet therapy in selected patients, and treatment of other contributing conditions are tailored to individual needs.
For patients with significant obstructive plaque and symptoms despite optimal medical therapy, or for those with acute coronary syndromes, procedures may be needed. These include percutaneous coronary intervention (PCI) with stenting and, in selected patients with complex disease, coronary artery bypass grafting (CABG). The choice between medical therapy and procedural treatment is individualized.
Cardiac rehabilitation is highly beneficial after acute coronary events, PCI, or CABG, and in many patients with stable disease. Care is typically coordinated by primary care clinicians and cardiologists, with input from preventive cardiologists, interventional cardiologists, dietitians, and others.
Detecting coronary plaque, even in patients without symptoms, can be a powerful motivator and a guide for personalized risk reduction. Studies have shown that early identification and intensive treatment of risk factors can slow plaque progression and reduce future cardiovascular events.
Red flag symptoms include sudden severe chest pain or pressure (especially with radiation to the jaw, arm, or back), severe shortness of breath, fainting, palpitations with lightheadedness, signs of stroke, profuse sweating, or signs of shock. These warrant immediate emergency evaluation, as they may indicate a heart attack or another life-threatening cardiovascular condition.