James J. Waring 613 



show the split and prolonged Q-R-S complex of delayed intraventricular con- 

 duction, which also appears under thyroid medication. 



Since the negative Q-R-S group in lead III, thought by many to be charac- 

 teristic of left ventricular hypertrophy, becomes positive in these cases after 

 thyroid medication, Fahr concluded that a negative Q-R-S group in lead III 

 is not due to a preponderance of musculature of the left ventricle. 



In 1927, Fahr" reiterated his conviction that heart failure, as evidenced by 

 dilatation of the heart, dyspnea on exertion, anasarca of the dependent por- 

 tion of the body, passive congestion of the liver, and edema of the lungs, is 

 not very infrequent in myxedema. If relief of these symptoms by thyroid ex- 

 tract in amount sufficient to bring the basal metabolism up to normal and to 

 cause the myxedema to disappear is evidence that both the myxedema and 

 the heart failure have the same cause, namely thyroid deficiency, then the 

 term "myxedema heart" is justified. 



Christian^ in his earliest paper (1925) did not note the changes so clearly 

 described by Zondek. In 1928^ he said that digitalis was without effect in a few 

 patients with enlarged heart and signs of congestive failure due to myxedema 

 but that thyroid medication resulted in marked improvement. In 1935'" he 

 thought pericardial effusions were probably present in those instances in 

 which gieat apparent enlargement of the heart markedly and rapidly de- 

 creased under thyroid therapy. In other instances atony as well as edema of 

 the heart muscle played a part in producing enlargement. 



Of 162 cases of severe myxedema studied with special reference to the cardio- 

 vascular system by Willius and Haines," 148 or 90 per cent showed no sub- 

 jective symptoms or objective evidence of organic cardiovascular disease. 

 Eleven or 7 per cent showed definite signs of organic cardiovascular disease 

 which was, in only one instance, appreciably influenced by the disappearance 

 of myxedematous symptoms under thyroid treatment. Analysis of X rays of the 

 hearts in this series was not given. Willius and Haines conclude that their 

 observations do not justify the establishment of a cardiac syndrome charac- 

 teristic of myxedema. 



Christian^ warned against the possibility of circulatory failure from the 

 incautious use of thyroid medication in myxedema. Although some cardio- 

 circulatory disturbance may be due to hypothyroidism and correctable in the 

 earlier stages, the later stages of circulatory disturbance will not be changed 

 because of their permanent organic nature. In intermediate stages a properly 

 balanced treatment with digitalis and thyroid substance is indicated and may 

 produce good results, provided the thyroid dosage does not overburden the 

 heart. 



In forty-eight myxedematous patients seen at the thyroid clinic of the Massa- 

 chusetts General Hospital in the preceding twelve years, Means, White and 

 Krantz"^ found only one in which there was a definite cardiac enlargement 

 which subsided under thyroid. They concluded that "myxedema heart" in 

 the sense of Zondek and Fahr, is far from common. On the other hand they 



