THE EFFECTS ON THE HEART OF LONG-STANDING BRONCHIAL ASTHMA

The literature of heart disturbances associated with asthma begins at an early date and is voluminous. It deals largely, however, with cardiac dyspnea or what is now called "cardiac asthma," wherein asthma is an expression of underlying cardiac injury. Einthoven,¹ von Basch,² Dixon and Brodie ³ and others ⁴ induced bronchospasm in animals and noted the circulatory effects. Although in these experiments the pulmonary mechanism of bronchial asthma probably was simulated in part, the results are at wide variance with one another. Only one detailed study was found concerning the effect of true bronchial asthma on the heart, a report by Götzl and Kienböck,⁵ who observed the heart radioscopically in two cases. A perusal of many of the modern textbooks reveals considerable lack of uniformity of opinion on this subject. In 1920 two of the great American systems of medicine were published; in one, Walker ⁶ writes: