ClotHound testing in a live porcine model

ClotHound uses two manually expandable spheres that open 3 to 16 mm, independently of each other.  The near sphere can slide 5cm back-and-forth along the shaft to loosen clot, and the far sphere is fixed to provide embolic protection downstream.

The study asked whether opening and moving these spheres injures the inner lining (intima) of arteries and veins.  It tested the first-generation device and the second-generation, design-freeze device.

• Study 1 (first-generation device, 2 pigs): spheres opened 40% wider than each vein's measured diameter, then moved back and forth five times over 3-5 cm in the jugular and iliac veins.
• Clot removal: a clot was placed in the lung artery (left lower lobe) of two pigs and removed with the device, using a 16F aspiration catheter.
• Study 2 (second-generation device, 2 pigs): veins and arteries were tested with the spheres at the native vessel diameter and at 20% wider.
• The vessels were then removed and examined under the microscope (H&E staining bv a veterinary pathologist). The study was done at the University at Buffalo under IRB approval.

Angiograms after the device was used showed no significant damage to the lining

of the veins or arteries. Under the microscope vessel wall integrity was intact and

tissue looked essentially normal with no significant inflammation. Some samples

showed small areas of lost lining that the pathologist described as artifact,

without inflammation or bleeding.

In the lung-artery clot model, the first pig had complete clot removal without

vessel damage. In the second. about 80% of the clot came out on the first pass

and a second pass removed the rest.