Basically cardiac asthma is not the actual asthma but it is a clinical condition which is caused by severe reflexive blocking and/or by the permanent edema of glands such as left ventricular failure. It is called asthma because it involves the asthmatic-type breathing due to the sudden blockage of pulmonary circulation. The wheezing in cardiac asthma is associated with heart failure not the inflammated airways caused due to the triggers as in asthma.

The major reason for cardiac asthma is the mechanical fault of the heart which may even be life threatening if not cured at the right time. The reduced pumping efficacy of the heart builds up fluid in the lungs which causes airways to narrow and consequently developing wheezing and other related symptoms. And thus it is given the name cardiac asthma since the symptoms of actual asthma and cardiac asthma are more or less similar.

Cardiac asthma is characterized by shortening of breath (with or without breathing), severe coughs, increased blood pressure, increased heart rate, and feeling of apprehension. Unlike shortening of breath early in the morning as experienced in any other asthma, the episodes of breathlessness is after a few hours of going to bed and the person has to sit upright to get the breath back.