Effectiveness of lipid microbubbles and ultrasound in declotting thrombosis.
The objectives of this study were to determine the effectiveness of lipid-encapsulated microbubbles and ultrasound (US) in recanalizing arteriovenous graft thrombi and the effect that tissue attenuation has on the success rate. A total of 55 thrombotic occlusions were created in four canines. The thrombosed grafts were randomly treated with two different 1-MHz US intensities, low (0.4 to 0.6 W/cm(2)) and high (10 W/cm(2)). Intragraft microbubbles were compared with intragraft saline and with the same dose of microbubbles given IV. IV microbubbles were also given both in the presence and absence of a tissue-mimicking phantom. High-intensity US (10 W/cm(2)) with intragraft microbubbles produced significantly higher patency and flow scores than did US with saline (p < 0.01). US with IV microbubbles had higher success rates in recanalizing thrombosed grafts than did US alone at all intensities. Attenuation reduced the rate at which successful recanalization occurred at both low and high intensities. US and microbubbles are capable of recanalizing acute arteriovenous graft thromboses. Higher intensities may be needed in the presence of tissue attenuation.
Internal Medicine/Cardiology Department, University of Nebraska Medical Center, Omaha, NE 68196-1165, USA.
Feng
F
Xie
Jeane M
JM
Tsutsui
John
J
Lof
Evan C
EC
Unger
Jason
J
Johanning
William C
WC
Culp
Terry
T
Matsunaga
Thomas R
TR
Porter
D000208:Acute Disease; D000818:Animals; D001166:Arteriovenous Shunt, Surgical; D004285:Dogs; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000628:therapy*; D008055:Lipids; D045423:Microbubbles; D019047:Phantoms, Imaging; D011859:Radiography; D011897:Random Allocation; D012965:Sodium Chloride; D013927:Thrombosis / Q000000981:diagnostic imaging / Q000628:therapy*; D014464:Ultrasonic Therapy / Q000379:methods*; D018615:Ultrasonography, Doppler, Color; D014654:Vascular Patency
D008055:Lipids; D012965:Sodium Chloride