TACHYCARDIA The heart action of a child, always rapid, shows an acceleration under the most varied conditions. Fever, excitement, bodily over exertion cause a more rapid increase in the pulse frequency in childhood than in later life. The pulse beats regularly and the accelerated heart continues to beat with the same force, as long as the canse is operative. Paroxysmal tachycardia is different, in that very decided acceleration of the heart-beat occurs in sudden attacks, in conjunction with unpleas ant sensations, palpitation, feeling of anxiety, outbreaks of perspira tion, general weakness and exhaustion.
The dispute as to whether paroxysmal tachycardia is simply a neurosis or an acceleration of the heart-beat dependent upon an organic basis. has not been decided since Bouveret's fundamental work. The occurrence of this affection in childhood and its disappearance, without leaving a trace, during childhood or later in life, shows that this anomaly may certainly depend upon purely functional (listurbances of the ner VOUS system of the heart also. Only older children suffer from this con dition. The duration of the attack varies between several hours and days, during which time the pulse-rate is rarely under 200.
The causes of paroxysmal tachycardia are in doubt, but in children especially, traumatic and psychic influences are considered the first occasions for the attacks, which sometimes alternate with other ner vous symptoms, such as asthma, migraine, vertigo, fear of noises. In childhood especially, relations between paroxysmal tachycardia and clinical signs of cardiac affectiom3 are absolutely absent. Hochsinger knows of two cases of this condition in which attacks occurred regularly with high-grade constipation, and always ceased after thorough evacua tion of the bowels. In the first child the attacks, began in the eighth, in the second, in the tenth year. The latter recovered.
attack may be of short or of long duration.
Respiration is not accelerated during the attack, while the secretion of urine considerably increases, except in a case of Herringham's, in which it decreased. When the attacks are very frequent and the con dition has lasted a long time, it may lead to cardiac hypertrophy, even in childhood, but this disappears with the disease.
'Whether, in the cases in which there is no organic heart affection, the cause is paralysis of the vagus (Bouveret), stimulation of the celerans (Tunker), or bulbar disturbance (Debove) remains undecided. According to Hochsinger's observation, a third form of tachycardia occurs in childhood, perennial tachycardia, as the result of compression of the vagus by enlarged bronchial glands. Tachycardia may be the single clinical symptom of hyperplasia of the bronchial glands. singer has observed three conclusive cases in children from three to five years of age, in whom permanent tachycardia occurred for about a year, following whooping-cough and rubeola, the pulse-rate, remain ing between 160 and 180; then it gradually ceased spontaneously. This could have been due to compression of the vagus only.
treatment of paroxysmal tachycardia in chil dren must regard the nervous origin of the condition and must pre vent the reflex product of attacks. Stimulating drinks, copious meals and violent exertion are forbidden; the bowels must be kept regular. In some cases the paroxysm may be stopped by strong pressure in the epigastrium, by forcibly stopping respiration or by compression of the carotids until vertigo occurs. In severe attacks the application of cold to the cardiac region, or a spray of ether or ethyl chloride is of use. Drugs are useless during the attack. Narcotics, taken internally or applied externally, may lighten the subjective symptoms during the attack.