What is cardiac asthma?

Cardiac asthma is not a form of asthma. It's a type of coughing or wheezing that happens with left heart failure. Depending on how severe the symptoms are, this wheezing can be a medical emergency.

Heart failure can cause fluid to build up in the lungs, a condition called pulmonary edema. It also can cause fluid to build up in and around the airways. This buildup of fluid can cause shortness of breath, coughing and wheezing. Because these symptoms are like those of asthma, the condition is called cardiac asthma.

True asthma is a long-term condition caused by inflammation of the airways. The inflammation narrows the airways, causing breathing trouble. True asthma is not caused by fluid in the lungs or heart disease. But growing research shows a connection between asthma and a higher risk of heart disease.

Knowing the difference between asthma and heart failure is important. That's because each condition has different treatments. Treatments for heart failure can help improve the symptoms of both heart failure and cardiac asthma. Overuse of treatments for true asthma, such as rescue inhalers, may be harmful and may worsen heart issues.

Dec. 30, 2025