TRANSVENOUS PROCUREMENT OF PULMONARY-ARTERY SMOOTH-MUSCLE AND ENDOTHELIAL-CELLS USING A NOVEL ENDOARTERIAL BIOPSY CATHETER IN A CANINE MODEL

Objectives. The aim of this study was to evaluate the performance of a new arterial biopsy catheter in obtaining pulmonary endovascular samp les in a canine model. Background. Percutaneous endomyocardial biopsy is a widely used and valuable procedure in the management of posttrans plant rejection and selected cardiomyopathies. A similar method of obt aining endoarterial biopsy samples would aid in the study, diagnosis a nd management of arterial diseases. Methods. Catheterization was perfo rmed in 19 dogs, each weighing 20 to 30 kg, through an 8F sheath in th e external jugular vein to obtain pulmonary endoarterial samples, The catheter consists of two sliding tubes: an inner one with a beveled op ening that accommodates endoarterial tissue by means of a vacuum and a n outer tube with a sharp distal edge that cuts the tissue when activa ted, Results. Overall, a total of 266 separate biopsy attempts were pe rformed, and 161 tissue samples were obtained (success rate 61%), With modifications in technique in the last nine dogs, 54 (93%) of 58 atte mpts were successful. There were no deaths, extravasation of contrast material on angiography or thrombi. Of 20 vessels,vith prebiopsy and p ostbiopsy angiograms, 1 developed transient spasm (5%). On microscopic examination of cross sections of 50 separate pulmonary endoarterial b iopsy samples, all had smooth muscle cells and 30 contained endothelia l cells (60%). The arteries of origin showed small intimal and medial tears and mild perivascular hemorrhage. Angiographic and pathologic ex amination of previously biopsied arterial segments 2 weeks (two dogs) and 8 weeks (two dogs) after the procedure showed patent vessels and n o thrombi, Histologically, the biopsy sites revealed mild neointimal a nd medial proliferation. Conclusions. This new endoarterial biopsy cat heter is safe and effective in obtaining pulmonary artery samples in n ormotensive dogs.