title: Low pressure radiofrequency balloon angioplasty: evaluation in porcine peripheral arteries.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the efficacy of radiofrequency-powered thermal balloon angioplasty in an in vivo porcine model.
  
  
  BACKGROUND
  Various modes of thermal energy used adjunctively during balloon angioplasty have demonstrated the potential to enhance the results of acute lumen dilation.
  
  
  METHODS
  In normal pigs, 75 peripheral arteries were dilated with a newly designed, radiofrequency-powered, thermal angioplasty balloon. All inflations were performed at 2-atm pressure for 85 s. Dilations were performed either with (hot) or without (cold) the application of heat. Lumen dimensions and vessel morphology were assessed with intravascular ultrasonography. At the end of each study, dilated arterial segments were harvested for histologic examination.
  
  
  RESULTS
  Single cold balloon inflations resulted in a 12.7% increase in arterial cross-sectional area whereas single hot inflations resulted in a 22.9% increase (p < 0.03). Similarly, when multiple cold inflations were compared with multiple hot inflations, two, three and four sequential hot inflations resulted in a significantly greater increase in cross-sectional area than an equivalent number of cold inflations (p < 0.03). Histologic examination demonstrated a temperature-dependent effect on the depth of medial necrosis and extent of arterial wall thinning (p < 0.001) as well as evidence for uniform alteration of elastic tissue fibers at temperatures of > or = 60 degrees C (p < 0.03).
  
  
  CONCLUSIONS
  Low pressure radiofrequency thermal balloon angioplasty results in a greater increase in cross-sectional area in porcine peripheral arteries than does nonheated conventional balloon angioplasty. The pathologic basis for this enhanced dilation may be a temperature-dependent effect on medial necrosis, thinning of the arterial wall or alteration of vascular elastic fibers, alone or in combination.
authors: Department of Internal Medicine and Cardiology, Hartford Hospital, University of Connecticut 06115.
authors: D B
authors: DB
authors: Fram
authors: L D
authors: LD
authors: Gillam
authors: T A
authors: TA
authors: Aretz
authors: R V
authors: RV
authors: Tangco
authors: J F
authors: JF
authors: Mitchel
authors: J P
authors: JP
authors: Fisher
authors: B W
authors: BW
authors: Sanzobrino
authors: F J
authors: FJ
authors: Kiernan
authors: S
authors: S
authors: Nikulasson
authors: A
authors: A
authors: Fieldman
mesh_terms: D000800:Angioplasty, Balloon / Q000009:adverse effects / Q000379:methods*; D000818:Animals; D002339:Carotid Arteries / Q000473:pathology; D004564:Electrocoagulation; D005069:Evaluation Studies as Topic; D005260:Female; D005263:Femoral Artery / Q000473:pathology; D007083:Iliac Artery / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D016491:Peripheral Vascular Diseases / Q000628:therapy*; D011846:Radio Waves; D013552:Swine; D013696:Temperature; D014463:Ultrasonography