Production of Temporary Valvular Lesions. 87 



started at the same point and traveled either along different 

 routes, or at varying rates along the same route. 



Complete heart-block without anatomical lesion in the auriculo- 

 ventricular system may possibly be of neurogenic or of circulatory 

 origin, or it may be ascribed to chemical agents, to asphyxia, or 

 to some hindrance to the passage of impulses from the terminal 

 arborizations of the conducting system to the ventricular muscula- 

 ture. 



A previous example of possible functional heart-block was 

 reported by Dr. Alfred Cohn. 1 In his case of transient complete 

 dissociation showing constantly varying ventricular complexes, 

 the patient recovered, so that there was no opportunity of deter- 

 mining whether or not there was an organic lesion in the aur idio- 

 ventricular system. 



58 (754) 



Methods for the production of temporary valvular lesions. 



By Carl J. Wiggers and Eugene F. Du Bois. 



[From the Physiological Laboratory, Cornell University Medical 

 College, New York City.] 



Experimental valvular lesions have been induced by a number 

 of investigators — stenoses by tightening of ligatures or clamps 

 about the valvular orifices, insufficiencies by tearing of valves 

 with sounds and glass rods or by cutting with specially constructed 

 valvulotomes. Such experimental stenoses may, if desired, be 

 temporary, and normal circulatory conditions may be subsequently 

 reestablished. Experimental insufficiencies such as have been 

 described, must, owing to the traumatic nature of the lesion, be 

 permanent. As no method for the production of temporary in- 

 sufficiencies has apparently been described, the following method, 

 which also permits a study of the intraventricular pressure changes, 

 was devised. 



Method. — A curved metal catheter (22 cm. long, internal 

 diameter 6 mm.) having toward the tip one or two openings 

 (6 mm. in diameter) and three centimeters from the tip a longi- 



1 Cohn, Proc. Soc. for Exper. Biol, and Med., Vol. IX, No. 2, p. 24, December, 

 ion. 



