IN-VITRO IDENTIFICATION OF ANGIOPLASTY-INDUCED INJURY BY USE OF VASCULAR ACOUSTIC EMISSIONS

Background We have developed a novel method of diagnosing stress-induc ed vascular injury. This approach uses the sound energy released from atherosclerotic arterial tissue during in vitro balloon angioplasty to characterize type and severity of induced trauma. Methods and Results Thirty-two postmortem human peripheral arterial specimens 1.0 cm long were subjected to in vitro balloon angioplasty with simultaneous acou stic emission monitoring. Specimens were examined before and after ang ioplasty to ascertain the extent of angioplasty-induced injury. Gross observation was used to identify dissection A three-dimensional intrav ascular ultrasound reconstruction technique was used to estimate the l uminal surface area of the specimen. Change in luminal surface area (p ostangioplasty minus preangioplasty) was used to quantify induced inju ry. The energy content and spectral distribution of the digitally acqu ired vascular acoustic emission (VAE) signals were computed. Compariso ns of angioplasty-induced trauma with VAE signal characteristics were made. Dissection (mural laceration of variable depth) was observed in 15 of 32 specimens. Eleven showed no evidence of induced dissection, a nd 6 had preexisting intimal disruptions. The energy content of the VA E signals collected from specimens with dissection was greater than th at obtained from those in which dissection was absent: 845+/-89.4 mJ ( mean+/-SEM; n=15) versus 128+/-40.8 mi (n=11; P<.001). Comparison of i nduced trauma and VAE signal energy demonstrated a proportional relati onship (r=.87, P<.001, n=32). Conclusions VAE signals contain informat ion characterizing type and severity of angioplasty-induced arterial i njury. Because vascular injury is related to adverse procedural outcom e, development of VAE technology as an adjunct to conventional diagnos tic modalities may facilitate optimal balloon angioplasty delivery and postprocedural care.