Novel Collagen Vascular Plug for Femoral Arteriotomy Sealing: Acute and Chronic In Vivo Studies
Authors: MITCHEL JOSEPH F. , AZRIN MICHAEL A. , FRAM DANIEL B. , QUIST WILLIAM C. , ARETZ THOMAS A. , SHWEDICK MICHAEL W. , WATERS DAVID D. , McKAY RAYMOND G. 
Published: June 2007

Background: The current use of collagen vascular hemostasis devices to percutaneously seal femoral arteriotomy sites is limited by a significant incidence of vascular complications. The purpose of the present study was to assess the efficacy of new collagen plug specifically designed to avoid these complications by accurately gauging the depth of the femoral artery and by minimizing the risk of intra‐arterial collagen deployment. Methods: The hemostasis device used in this study consists of a multicomponent collagen plug with an external rigid collagen tube lined by an inner layer of absorptive sponge collagen. Placement of this plug is facilitated with a specialized two‐lumen dilator, which localizes the arterial surface using a “bleedback” mechanism from one of the lumens, and prevents the placement of collagen through the arteriotomy site. The acute efficacy of this device was assessed in 26 adult dogs in which 36 collagen plugs were used to seal 8Fr femoral arteriotomies. An additional 16 arteriotomies treated with standard manual compression served as study controls. Following plug placement or manual compression, all puncture sites were observed for bleeding and hematoma formation over a 45‐minute period. Patency of each instrumented artery was assessed with serial femoral angiography and localization of each plug was confirmed with surgical cutdown at the puncture site. The chronic efficacy of this device was assessed in three pigs in which three collagen plugs were used to seal 8Fr femoral arteriotomies. The three animals were subsequently sacrificed at 7,14, and 30 days, respectively, for histologic analysis. Results: In acute animals, all 36 plugs were successfully placed without evidence of vascular compromise or intra‐arterial collagen deployment. In nonanticoagulated animals, hemostasis was achieved within 5 minutes in 10 of 10 plugs placed with a skin‐to‐arlery distance > 1.8 cm, in 4 of 7 plugs with a skin‐to‐artery distance of 1.2–1.7 cm, and in 0 of 9 plugs with a skin‐to‐artery distance < 1.2 cm. In anticoagulated animals, hemostasis within 5 minutes was demonstrated with 8 of 10 plugs with a skin‐to‐artery distance > 1.8 cm; small hematomas occurred in the remaining two animals in the setting of a PTT > 100 seconds. Time to hemostasis was significantly less for collagen plugs than manual compression in both nonanticoagulated animals (plug 17 ± 16 minutes; manual compression 28 ± 5 minutes; P < 0.03) and anticoagulated animals (plug 6 ± 2 minutes; manual compression 42 ± 4 minutes; P < 0.01). Chronic studies demonstrated femoral artery patency in all three pigs. Histologic analysis demonstrated progressive collagen resorption with no difference between collagen plug placement or manual compression at 30 days. Conclusions: The local hemostasis device utilized in this study resulted in accurate placement of a collagen plug immediately adjacent to the arteriotomy site with no evidence of acute or chronic vascular compromise or intra‐arterial collagen deposition. Hemostasis with shorter compression times than with standard manual techniques was achieved at puncture sites in which the skin‐to‐artery distance was > 1.8 cm and the anticoagulation profile was not excessive. At 1 month postplacement, there is no histologic difference between plug use and standard manual compression. (J Interven Cardiol 1996;9:25–33)