Cardiac Hypertrophy in Arteriovenous Aneurysm.

Arteriovenous aneurysm offers an opportunity for the study of factors concerned in the production of cardiac hypertrophy. In the presence of an arteriovenous fistula between the carotid artery and jugular vein, we have confirmed the observation of an immediate enlargement of the cardiac shadow as the fistula is opened. This we feel can be nothing other than dilatation of the heart as a result of the blood shunt. Thus, one of the primary factors in this condition seems to be cardiac dilatation.It is interesting to note that in a series, 10 dogs in each of which an arteriovenous aneurysm was produced, but thrombosed within a day or two, we found heart weight-body weight ratios ranging from .00690 to .00900, with an average of .00850, which, in our opinion, are not increased enough to be considered significant of actual hypertrophy. The ratios of left ventricular weight were likewise within our normal limits. (See Table I.)In one dog, No. 366, 2 unsuccessful femoral fistulae and one unsuccessful carotid jugu...