title: Effects of Triple Cryoenergy Application on Lesion Formation and Coronary Arteries in the Developing Myocardium.
abstract: To improve long-term outcome after cryoablation of substrates of supraventricular tachycardia, application of two and three consecutive freeze-thaw cycles has been performed. The effect of triple freeze-thaw cycles on lesion formation within developing myocardium and coronary arteries, however, has not been studied yet. In eight piglets (mean age 15 weeks, weight 15-20 kg), 30 cryolesions (three consecutive freeze-thaw cycles) were applied to the atrial aspect of both AV valve annuli (n = 18) as well as to ventricular myocardium below the valves (n = 12). Coronary angiography was performed before and after cryoenergy application. The animals were reevaluated by coronary angiography and intracoronary ultrasound (ICUS) after 48 h. All hearts were removed for histological examination of the lesions subsequently. After staining (hematoxylin-eosin, desmin immunohistochemistry), lesions was measured by planimetry with a digital virtual miscroscope analysis system and volumes of the cryolesions were calculated. Mean atrial lesion volume was 190.68 ± 167.53 mm3(n = 18), and mean ventricular lesion volume was 184.34 ± 107.42 mm3(n = 12). Compared with previously reported data on lesion volumes after single and double freeze-thaw cycles, lesions were significantly larger. Coronary arteries were unaffected on coronary angiography as well as on ICUS. No affection of coronary arteries was found on histological examination. Application of three consecutive freeze-thaw cycles resulted in increased lesion volume compared with single and double freeze-thaw cycles. No affection of the coronary arteries was evident. To evaluate the clinical benefit and safety of triple cryoenergy application for catheter ablation, prospective randomized trials are required.
authors.affiliation: Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Center, Georg August University, Robert-Koch-Str. 40, 37099, Göttingen, Germany. ukrause1@gwdg.de.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Krause
authors.affiliation: Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Center, Georg August University, Robert-Koch-Str. 40, 37099, Göttingen, Germany.
authors.forename: Filipe D
authors.initials: FD
authors.lastname: Abreu da Cunha
authors.affiliation: Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Center, Georg August University, Robert-Koch-Str. 40, 37099, Göttingen, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Backhoff
authors.affiliation: Department of Cardiology and Pneumology, University Medical Center, Georg August University, Robert-Koch-Str. 40, 37099, Göttingen, Germany.
authors.forename: Claudius
authors.initials: C
authors.lastname: Jacobshagen
authors.affiliation: Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Center, Georg August University, Robert-Koch-Str. 40, 37099, Göttingen, Germany.
authors.forename: Sophia
authors.initials: S
authors.lastname: Klehs
authors.affiliation: Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Center, Georg August University, Robert-Koch-Str. 40, 37099, Göttingen, Germany.
authors.forename: Heike E
authors.initials: HE
authors.lastname: Schneider
authors.affiliation: Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Center, Georg August University, Robert-Koch-Str. 40, 37099, Göttingen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Paul
mesh_terms: D000818:Animals; D006348:Cardiac Surgical Procedures / Q000379:methods; D017115:Catheter Ablation; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000293:injuries; D003452:Cryosurgery / Q000379:methods; D006352:Heart Ventricles / Q000473:pathology / Q000601:surgery*; D008943:Mitral Valve / Q000473:pathology / Q000601:surgery*; D009206:Myocardium / Q000473:pathology; D013552:Swine; D013617:Tachycardia, Supraventricular / Q000601:surgery*; D014261:Tricuspid Valve / Q000473:pathology / Q000601:surgery*
keywords: Catheter ablation; Coronary artery; Cryoenergy; Developing myocardium; Supraventricular tachycardia