22 Fibrillation in the MaTumalian Heart. 



direct improvement of conductivity or (h) secondarily through the slowing 

 of the rate of succession which they may induce, i.e. by lowering excitability, 

 provided that this effect is not attended by a proportionate lowering of 

 conductivity. Adrenalin is notably useful in this respect, as indicated by 

 the remarkable improvement in conduction often seen under its influence, 

 especially evident in the auricles, where a strikingly slow contraction wave, 

 present during gravely depressed conduction, may be replaced by an 

 approximation or a return to the normal type. Hence the special utility of 

 adrenalin in dealing with forms of slow coarse fibrillation, already described, 

 and also with fibrillar beats — unless the damage in the latter case has been 

 carried to an irreparable stage (fig. 9). 



The success of the above-mentioned methods of obtaining recovery from 

 typical fibrillation, induced by means that did not permanently damage the 

 heart, has been such that in recent years of experimentation there has not 

 been failure in any instance. 



For valued assistance in some of the experiments of this investigation, I 

 have to record my thanks to Drs. Gr. Spencer Melvin and J. R. Murray. 

 A portion of the costs was defrayed by a grant from the Carnegie Trust. 



Harbison and Sons, Printers in Ordinary to His Majesty, St. Martin's Lane. 



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