xii, B, 2 Mendoza-Guazon: Anatomicopathologic Lesions 75 



others believe that the degeneration of the vagus nerve is the 

 cause of the cardiac dilatation. Albert thinks that the increase 

 of tone of the vagus or its abnormal irritability is the immediate 

 cause of the hypertrophy and dilatation of the right ventricle, 

 while Villareal mentioned that in Japan Miura laid great em- 

 phasis on the increase of the second pulmonic sound in diagnos- 

 ing cases of beriberi. 



Miura (35) explains the condition of dilatation-hypertrophy 

 of the right heart in beriberi as due to a diminution in the mass 

 of the lungs through the raising of the diaphragm and the con- 

 traction of the ultimate branches of the pulmonary artery 

 through the action of the beriberi poison; Yamagiva,(54) to the 

 contraction of the pulmonary arterioles. Ogata (38) states that 

 there is no diminution of the lumen of the pulmonary vessels in 

 the said disease, and that, if there is any contraction of these 

 vessels, it is only due to post-mortem rigidity. 



Matsuoka,(3l) in 1911, studied the pulmonary oedema in beri- 

 beri and came to the conclusion that in that disease the con- 

 dition is due to an early weakening of the left ventricle and 

 that the hypertrophy of the right ventricle found in beriberi 

 favors the raising of the pressure in the pulmonary artery and 

 the occurrence of pulmonary oedema. Later in 1915 the same 

 author, after an exhaustive work on changes in the lungs in 

 beriberi, came to the following conclusions: 



1. Although pathognomonic pictures of beriberi lungs are still wanting, 



they have the following characteristics: 



a. Diminished air capacity or collapse (in spite of vicarious emphysema 



in one part), and following generally upon this small volume and 

 sharp margins. 



b. Especially important is the congestion-oedema; this is not confined to 



the agonic period, in which there may be paralysis, but a true con- 

 gestion-oedema. Heart-failure cells are to be found not infrequently. 

 Distinct splenisation is present in marked cases of beriberi. 



2. The above-mentioned oedema is of constant occurrence, in many areas 



circumscribed or diffuse. 



3. Besides the ascent of the diaphragm following on paresis, there exist for 



the explanation of the collapse (of varying degrees) numerous im- 

 portant factors, of which hydrothorax is perhaps the most important. 



4. For the setting up of dilatation and hypertrophy of the right heart, 



congestion and congestion-oedema must work hand in hand with the 

 collapse. 



Tadaharu Maruyama(48) thinks that the cause of the nerve 

 and muscle degenerations is probably some poison of the exis- 

 tence of which there is as yet no proof. 



Hess (26) believes that the pathogenesis of the cardiac enlarge- 



148932 3 



