Angiocardiographic demonstration of occlusive auricular thrombi in dogs.

Simulated occlusive auricular thrombi were produced in six dogs by surgically invaginating the left auricular appendage. Angiocardiographic studies were performed in five of the dogs and in each case revealed these thrombi as clear cut filling defects. The significance and clinical application of these observations is discussed. IN a previous paper' it was postulated that in view of the encouraging progress made in both the diagnosis and surgical allevia-tion of a variety of cardiovascular lesions, it might be hoped that ultimately such thrombi could be demonstrated by angiocardiographic technique and subsequently removed in conjunction with a mitral valvotomy. Since such thrombi have invariably terminated fatally, early and accurate diagnosis could conceivably represent a life saving measure. The incidence of occlusive auricular thrombi has been variously reported to range from 1 in 30002 to 1 in 5403 autopsies. The incidence of such thrombi in patients with rheumatic heart disease has been reported as 1 in 52 cases by Garvin4 and 1 in 32 cases by Wallach and coworkers.3 Evans and Benson5 found an incidence of one out of eight patients coming to autopsy with mitral stenosis. The value of angiocardiography in detecting a similar object within the heart has already been demonstrated in man by Bahnson and Newman.6 They presented the case of a large pedunculated myxoma, which was demonstrated as a large filling defect in the right auricle following injection of Diodrast through a number 8 catheter. The tumor was successfully removed but the patient succumbed 24 days later of postoperative complications. As a FIG. 1. The heart from dog 1 is shown viewed from apex to base with the lower two thirds of both ventricles removed. The invaginated left auricular appendage, T, can be seen protruding into the left auricular cavity LA. result of our experience with four case of oc-clusive auricular thrombi, we decided to study the diagnostic efficacy of angiocardiography in dogs following the insertion of anl artificial thrombits into the left auricle.