Transcatheter aspiration: The key to successful percutaneous treatment of deep venous thrombosis?

Rationale and Objectives, The purpose of this study was to examine transcat heter aspiration as an adjunct to local thrombolysis in a porcine model of acute deep venous thrombosis (DVT). Materials and Methods. DVT was induced in both hind limbs of five pigs. Thi rty minutes later, bilateral thrombolysis was performed by using infusion g uidewires placed coaxially through occlusion balloon catheters. A temporary venous filter was then placed in the inferior vena cava. The balloon cathe ters and infusion wire were removed, a 14-F sheath was placed on the right side, and aspiration of residual thrombi was attempted with 8- and 6-F cath eters. At autopsy, the mass of any thrombus in the iliofemoral veins was me asured, and residual thrombosis in the venous tributaries was graded at fou r sites. Thromboemboli in the inferior vena cava and the pulmonary circulat ion were also collected and weighed. Results. With aspiration and lysis, the iliofemoral veins were cleared of t hrombus in three of five limbs; from the remaining two, only 0.09 and 0.15 g of thrombus were harvested. Except for the deep femoral vein in two legs, tributaries were free of thrombus. After thrombolysis alone, thrombi range d in mass from 0.54 to 1.14 g (median, 0.70 g). Some thrombi were observed in most tributaries. One or two small emboli were found trapped by the cava l filter and in the pulmonary circulation in four and three pigs, respectiv ely. Conclusion. The primary axial veins and their tributaries can be rapidly cl eared of thrombus by using thrombolysis with transcatheter aspiration, but this procedure is associated with the risk of pulmonary embolism.