Coronary artery disease (CAD), which affects over 18 million adults in the United States, occurs when one or more coronary arteries narrow due to the buildup of plaque. This plaque is made up of a clump of cholesterol, fats, blood cells, and other materials.

If doctors cannot identify and treat it in time, CAD can lead to a heart attack.

Diffuse coronary artery disease is less common than standard CAD, but can be a more challenging form of heart disease. It’s characterized by multiple or especially long, continuous plaques within the arteries supplying blood to the heart.

Cardiac imaging can usually diagnose diffuse CAD. But some standard treatments for heart disease may not be possible if the disease is diffuse.

With aggressive care and a heart-healthy lifestyle, many people with diffuse CAD can often live a long and active life.

What makes CAD diffuse?

The term diffuse CAD can be used to describe either:

  • a significantly long narrowed portion (greater than or equal to 20 millimeters) of a coronary artery
  • an artery that has several narrowed sections (greater than or equal to 70 percent narrowed) separated by relatively healthy portions of the artery
Was this helpful?

The causes of diffuse CAD are the same as standard CAD. Plaque is more likely to build up inside arteries that have been damaged or burdened by health problems, such as high cholesterol and high blood pressure.

Other risk factors for CAD include:

  • diabetes
  • obesity
  • sedentary lifestyle
  • smoking

Diffuse CAD is often a more advanced stage of CAD. Still, it’s possible to have diffuse CAD without knowing it. A comprehensive heart examination or, in some cases, a heart attack, may be what reveals the presence of multiple blockages or lengthy plaques in one or more coronary arteries.

One of the main imaging tests doctors use to confirm diffuse CAD is coronary computed tomography angiography (CCTA).

The screening uses an injection of contrast material and CT scanning equipment to reveal detailed images of how much the coronary arteries have narrowed. These 3D scans provide a better look at the heart and its blood vessels.

Other standard cardiac imaging may also help diagnose CAD and other conditions, such as valve disease. These tests include:

Doctors treat CAD in a few different ways, including:

The best option will depend on the severity of the disease, age, and overall health. For example, someone who’s particularly frail may not be a good candidate for open heart surgery.

The anatomy of a heart with diffuse CAD may also make certain procedures unsafe. A coronary artery that’s severely narrowed by multiple plaques or one or two long plaques may not be salvageable through stenting or surgery.


Doctors can often treat mild cases of diffuse CAD with medications used to treat standard CAD. These include:


A 2018 study suggests that new generation drug-eluting stents may be safe and effective treatment options for certain people with diffuse CAD.

Stents are small, flexible mesh tubes placed with a catheter inside a coronary artery at the site of a blockage. The stent keeps the artery open in order to improve blood flow.

Drug-eluting stents are coated with a medication that’s slowly released to help prevent the artery from narrowing again (known as restenosis).


Likewise, a 2017 study suggests that certain people with diffuse CAD also may benefit from coronary artery bypass surgery. It’s a procedure that takes a blood vessel from elsewhere in the body and attaches (or grafts) it to a coronary artery affected by CAD.

The surgeon attaches the graft above and below the narrowed portion of the artery. This allows blood to flow around (bypass) the section blocked by plaque.

Stem cell therapy

A 2020 study suggests that some people with diffuse CAD may respond well to stem cell therapy. But this type of treatment is still in its early stages.

Stem cells are cells capable of becoming healthy cells that serve a specific purpose, such as replacing damaged tissue.

A small 2019 study found that people with diffuse CAD had better outcomes with surgery than with medication. The mortality rate for those who had surgery was less than 3 percent, but it was 14 percent for those who only took medication. The researchers did highlight the need for larger studies to confirm the results.

But the outlook for diffuse CAD is still less positive than for standard CAD. A 2015 article on surgical treatment of diffuse CAD suggests that even individuals undergoing lifesaving bypass surgery can face higher mortality rates than those with less complex CAD.

While certain people with diffuse CAD can be treated effectively with stents or bypass surgery, others may not be able to have those treatments. The mortality rate for this group can be very high.

If you’re at risk for CAD, it’s important to talk with your doctor about screening. The sooner your doctor notices plaque forming in your arteries, the better your chances of avoiding severe diffuse CAD.

Having diffuse coronary artery disease is a greater burden than other types of heart disease. But with advances in treatment, it may be an increasingly manageable condition for many people.

Finding a cardiologist and surgical hospital with experience managing diffuse CAD is key. It’s also important to do what you can to live a heart-healthy lifestyle that includes regular exercise, a balanced diet, and no smoking.