Removal of focal atheromatous lesions by angioscopically guided high-speed rotary atherectomy. Preliminary experimental observations.

A new high-speed rotary atherectomy device, inserted over a guide wire and directed with an angioscope, offers the potential of restoring patency of outflow vessels by "boring out" the atheromatous lesion of the orifices of runoff vessels. The device was tested on 68 cadaver arteries with atheromatous lesions involving the superficial femoral, popliteal, and tibial arteries. This was performed with either free segments or in situ with the device placed through a popliteal arteriotomy. The gross results of rotary atherectomy were assessed by angioscopy, angiography, or both. The luminal surfaces were studied with scanning electron microscopy and transverse sections of vessels were studied with light microscopy. The pulverized atheroma, in colloidal suspension, was analyzed for particle size by Coulter counter. The effect of a colloidal suspension of atheromatous particles on distal capillary circulation was measured in animal experiments. Obstructive lesions were successfully removed in 36 of 37 stenotic arteries (97%) and 18 of 31 completely occluded arteries (58%), an overall efficacy of 54 of 68 (79%). In successfully atherectomized arteries, angioscopy and angiography demonstrated a widely patent, smooth, polished surface. Light microscopy demonstrated removal of the diseased intima with maintenance of the outer media and adventitia. The pulverized atheroma particles were generally smaller than red blood cells and injection of the colloidal atheroma into canine femoral arteries failed to produce local tissue injury. We conclude that in the human cadaver this atherectomy device effectively enlarges and recanalizes obstructed superficial femoral, popliteal, and tibial arteries.(ABSTRACT TRUNCATED AT 250 WORDS)