title: Experimental determination of the best time and duration for endovenous great saphenous vein electrocoagulation.
abstract: OBJECTIVE
  Endovenous electrocoagulation provokes immediate selective venous wall necrosis. In this study, we aim to determine the best power and time of electrocoagulation necessary to cause intima and media but not adventitia layer damage in great saphenous vein (GSV) insufficiency treatment.
  
  
  METHODS
  We studied 100 varicose GSV fragments submitted to endovenous electrocoagulation. The power (60, 90, or 120 W) and time (5, 10, or 15 seconds) were randomly assigned. The fragments were submitted to histopathologic examination to analyze the depth of tissue necrosis. Dose-response models for the analysis of binary data were used to identify the best association between power and the time of electrocoagulation necessary to cause intima and media but not adventitia layer necrosis. We also applied a logistic regression model to investigate the impact of body mass index and GSV diameter on the electrocoagulation effects.
  
  
  RESULTS
  The time (odds ratio [OR], 1.26; P = .0009) was found to be a stronger predictor of the depth of vessel necrosis than the power of electrocoagulation applied (OR, 1.05; P < .0001). The power and time that were most likely to cause intima and media but not adventitia layer destruction were 60.4 W × 5 seconds, 58.8 W × 10 seconds, and 8.9 W × 15 seconds. The initial GSV diameter (median, 5.36 mm; minimum, 2.3 mm; maximum, 10 mm; OR, 0.96; P = .82) and body index mass (median, 24.7 kg/m(2); minimum, 15.6 kg/m(2); maximum, 36.2 kg/m(2); OR, 1.08; P = .26) showed a poor correlation with the depth of histologic vessel destruction.
  
  
  CONCLUSIONS
  The time of electrocoagulation strongly predicts the depth of GSV wall necrosis more than the amount of power applied. Determination of the best time and power of electrocoagulation ratio may help optimize GSV endovenous electrocoagulation closure rates and decrease the complications index. The GSV diameter and body mass index do not influence endovenous electrocoagulation effects.
authors.affiliation: Dante Pazzanese Cardiovascular Institute, São Paulo, Brazil. Electronic address: vascular369@hotmail.com.
authors.forename: Fabio Henrique
authors.initials: FH
authors.lastname: Rossi
authors.affiliation: Dante Pazzanese Cardiovascular Institute, São Paulo, Brazil.
authors.forename: Camila Baumann
authors.initials: CB
authors.lastname: Beteli
authors.affiliation: Dante Pazzanese Cardiovascular Institute, São Paulo, Brazil.
authors.forename: Mabel Barros
authors.initials: MB
authors.lastname: Zamorano
authors.affiliation: Dante Pazzanese Cardiovascular Institute, São Paulo, Brazil.
authors.forename: Patrick Bastos
authors.initials: PB
authors.lastname: Metzger
authors.affiliation: Dante Pazzanese Cardiovascular Institute, São Paulo, Brazil.
authors.forename: Cybelle Bossolani
authors.initials: CB
authors.lastname: Onofre Rossi
authors.affiliation: Dante Pazzanese Cardiovascular Institute, São Paulo, Brazil.
authors.forename: Nilo Mitsuru
authors.initials: NM
authors.lastname: Izukawa
authors.affiliation: Dante Pazzanese Cardiovascular Institute, São Paulo, Brazil.
authors.forename: Amanda Guerra
authors.initials: AG
authors.lastname: de Moraes Rego Sousa