title: [Anatomopathological and biochemical correlation of lesions produced by standard and irrigated 4 mm radiofrequency catheters].
abstract: OBJECTIVE
  The influence on the size of radiofrequency lesions by cooling of the tip of the electrode remains unclear. Moreover, the possible effects of two different cooling systems, closed and open, have not been well differentiated. We designed this study to compare both systems of irrigated-tip catheters and the lesions produced with standard 4 mm catheters and also to evaluate the pathological and biochemical marker release correlation (cardiac troponin I) in an experimental model.
  
  
  METHODS
  The study was performed in 20 pigs. Applying between 1-8 radiofrequency pulses, at a power of 15, 25 or 50 watts, for 15-60 seconds to each animal. After 7 days, the pigs were sacrificed for anatomopathological study.
  
  
  RESULTS
  A total of 54 lesions were produced, 25 with standard catheters and 29 with irrigated catheters. The mean volume of the lesions produced with standard catheters was 146 +/- 110 microl and with irrigated-tip catheters 856 +/- 864 microl (p < 0.001). Peak values of cardiac troponin I were also higher for irrigated catheters (18 +/- 15 ng/ml) than for standard (6.5 +/- 3 ng/ml). The correlation between the size of the lesion and the levels of cardiac troponin I were 0.86 and 0.79 with the standard and irrigated-tip catheters, respectively. The incidence of cratering was higher with standard catheters (60%) than with irrigated (27%).
  
  
  CONCLUSIONS
  The lesions produced with an irrigated catheter are greater than those observed with standard catheters. The mean peak value of postablation cardiac troponin demonstrate a good correlation with the real size of the necrosis.
authors.affiliation: Servicio de Cardiología. Unidad de Arritmias. Hospital Ramón y Cajal. Departamento de Medicina. Universidad de Alcalá. Madrid.
authors.forename: A
authors.initials: A
authors.lastname: Hernández Madrid
authors.forename: J M
authors.initials: JM
authors.lastname: del Rey Sánchez
authors.forename: J M
authors.initials: JM
authors.lastname: González Rebollo
authors.forename: T
authors.initials: T
authors.lastname: Alvarez Mogollón
authors.forename: C
authors.initials: C
authors.lastname: Correa
authors.forename: A I
authors.initials: AI
authors.lastname: Ortiz Chercoles
authors.forename: A
authors.initials: A
authors.lastname: Socas
authors.forename: R
authors.initials: R
authors.lastname: Lobelo
authors.forename: G
authors.initials: G
authors.lastname: Peña
authors.forename: J
authors.initials: J
authors.lastname: Mercader
authors.forename: E
authors.initials: E
authors.lastname: Ripoll
authors.forename: C
authors.initials: C
authors.lastname: Moro
mesh_terms: D000818:Animals; D017115:Catheter Ablation; D009206:Myocardium / Q000473:pathology; D013552:Swine