Important, although by no means frequent, arc the changes in the structure of the heart valves. Next to rheumatism, scarlet fever is the most common cause for the development of valvular defects. There does not appear to be any definite relationship between the scarlatinous synovitis and the endocarditis.
That both complications may occur in the same patient is seen in the following case, that of an eleven-year-old girl, who suffered from a mild attack of the disease (maximum temperature, 39.2° C., 102.5° F., on the second day). Lysis was interrupted on the sixth (lay by the occur rence of a svnovitis in both wrists (swelling of the right wrist). On the eighth clay the swelling diminished in extent; on the ninth clay the tem perature fell to 3S° C. (100° F.), but not until the fifteenth day was the normal temperature reached. The heart was normal until the twelfth day, when the apex beat passed from the fourth intercostal space, inside of the mammillary line to 1 cm. to the left of the mammillary line. Heart action became more rapid, of pendulum-like rhythm.
On the fourteenth clay, increased heart action, soft systolic and short diastolic sounds at the apex. Both sounds, as well as increased area or cardiac dulness, present until the dismissal of the patient on the thirty-second clay. According to the mother of the patient, the child has remained perfectly well since.
It is not often possible to determine the exact time when the endo carditis first appears. As a rule, the onset of this complication is extremely insidious, without any subjective manifestations. Eternal vigilance is necessary if one wishes to learn of the existence of the endo carditis at the earliest possible moment. Otherwise, its presence may go unnoticed.
Also of great importance are those cardiac complications which make their appearance in about five per cent. of the cases at the end of the first or the beginning of the second week, seldom later than this (fifth week).
Anna P., ten years old, entered hospital on first clay of disease. Mild attack of scarlet fever (maximum temperature, 39.3°C. on third day). No evidence of circulatory disturbance other than the typical primary increased frequency of pulse rate. Decline of temperature by lysis, beginning on third day; uninterrupted decline.
In spite of this apparently smooth progress of the disease, the cardiac disturbance is none the less severe, the first symptom being noted on the sixth clay, at a time when all the active manifestations of the disease are receding. The first heart tone becomes impaired. The following day the pulse and heart action are lessened in frequency (pulse, SO) and become arrhythmic: on the eighth day cardiac dulness extends to the left, the apex beat is heaving and more visible. At the same time the first tone is displaced by a distinctly systolic murmur. In the evening the patient complains of palpitation. The arrhythmia, bratty cardia, dilatation and systolic murmur continue unchanged till the end of the third week. No subjective symptoms are noted. On the twenty third day no symptoms are evident.
In sonic cases the symptomatology of cardiac disturbances is more complicated, because the condition becomes worse. The second pulmonic sound is accentuated; there is duplication of the second tone at the apex, less often of the first. The pulse is small and weak; the afternoon tem perature may rise to 3S° C. (100.4° F.), but not higher. Some children become strikingly pale; the face is puffy. There is usually more or less feeling of lassitude and weariness. In marked contrast to the post diphtheritic cardiac disturbances, of which the condition strongly reminds one, the majority of these children feel entirely well. The clinical picture of these cases is never so severe as is seen in diphtheria. Sudden death never occurs. The fact that these cardiac disturbances arc met with almost exclusively in the mild eases of scarlet fever may be accepted as evidence that they are caused by the products of the infection, i.e., a toxremia. But it is impossible to determine whether a myocarditis is the basis of this disturbance. I have proposed the name myasthenia corths for this affection. In almost fifty per cent. of these cases resolution occurs in from two to three weeks; in the remaining fifty per cent. there is a permanent systolic murmur, arrhythmia and enlargement of the heart, although the patient is not invalided in the least.