Asthma and cardiac dyspnea; a differential diagnosis.

There appear to be no infallible guides by which to differentiate between cardiac insufficiency and asthma as a cause of dyspnea, wheezing and coughing in elderly patients. Many of the symptoms of one condition are also symptoms of the other. Even the results of therapeutic trial cannot be relied upon to establish diagnosis, for drugs effective in treatment of heart disease may also help relieve asthma, and vice versa. Although there is no single factor that can be considered pathognomonic, there are certain symptoms and results of tests which are more strongly indicative of one condition than of the other. Careful evaluation of all factors, while it may not serve to establish unequivocal diagnosis, will provide a basis for judicious treatment of the patient.