Dyspnea or Shortness of Breath - Symptoms, cardiac & non-cardiac causes

Dyspnea is difficulty breathing or an uncomfortable awareness of breathing. It is one of the cardinal symptoms of cardiac (heart) disease.

If you experience dyspnea, you may have difficulty getting enough air into your lungs. You may feel claustrophobic or you may sigh a lot. Sometimes shortness of breath can be relieved by taking a few deep breaths or by resting.

What are the noncardiac causes of dyspnea?
Dyspnea is a relatively common occurrence. It does not always indicate illness. Strenuous activity or anxiety may produce shortness of breath. Dyspnea may be caused by obesity or may develop as part of an allergic reaction.

Dyspnea occurs as a symptom of a variety of illnesses. These include neuromuscular, pulmonary (lung), cardiac (heart), and other diseases.. Some of the pulmonary illnesses which have shortness of breath as a symptom include: emphysema, obstructive airway disease, pulmonary embolism, bronchitis, and asthma.

What are the cardiac causes of dyspnea?
A major cardiac cause of dyspnea is heart failure - in particular, failure of the left lower heart chamber (left ventricle). In addition to shortness of breath, you may experience upper abdominal pain, and excessive night time urination (nocturia). Usually the shortness of breath worsens on exertion, and is partially or completely relieved by rest. If you have left ventricular heart failure, you may avoid dyspnea in bed by sleeping with two or more pillows.

If you have heart failure, you may experience dyspnea when you are sleeping. This is known as "paroxysmal nocturnal dyspnea.". Shortness of breath usually occurs two to four hours after falling asleep. You will awaken with dyspnea, sweating, coughing and perhaps wheezing. Your symptoms may be relieved by getting out of bed or by sitting on the side of the bed. The relief comes gradually, and may take ten to twenty minutes.

Dyspnea on exertion may signify another cardiac illness called, "coronary artery disease." If you have coronary artery disease, dyspnea may be accompanied by chest discomfort or pain (angina). Dyspnea which is also accompanied by chest pain, may indicate an acute myocardial infarction(heart attack).

If you have a history of mitral valve disease (deformity of one of the heart's valves), the sudden onset of dyspnea may mean that you have developed a specific arrhythmia (irregular heart rhythm). This arrhythmia is called, "atrial fibrillation", and is rarely life threatening.

The onset of dyspnea in cardiac disease is a serious occurrence. It may indicate a worsening of your condition. If you have a history of heart disease and you suddenly have episodes of shortness of breath, call you health care professional.

How are the underlying diseases diagnosed?
Your doctor will take a complete medical history and perform a physical examination to determine the cause(s) of your shortness of breath. He will be particularly interested in hearing your account of the intensity, severity, and frequency of the dyspnea. He will also question you as to the quality of the dyspnea and your reactions and feelings about the episodes.

If a cough accompanies your dyspnea, your physician will want to know if it occurs before or after the shortness of breath.

Your doctor may order include blood tests, x-rays and electrocardiograms .

How is dyspnea treated?
Therapy for dyspnea usually consists of treating the underlying illness(es). Depending on the cause, treatment may range from instruction as to what to do when you experience shortness of breath, to medications, to hospitalization.