OBJECTIVE: To determine the importance of the variables: Energy Intensity (I), Power (P) and Time of Application (T) in the histological changes occurring in lower limb varicose vein submitted to endovascular electrocauterization. METHOD: Prospective experimental study conducted in patients undergoing great saphenous vein electrocauterization according to a randomization table - GI: I=0J, P=0W, T=15s; GII: I=300J, P=60W, T=5s; GIII: I=600, P=60W, T=10s; GIV: I=900J, P=60W, T=15s; GV: I=450J, P=90W, T=5s; GVI: I=900J, P=90W, T=10s; GVII: I=1350W, P=90W, T=15s; GVIII: I=600, P=120W, T=5s; GIX: I=1200J, P=120W, T=10s; GX: I=1800J, P=120W, T=15s. The fragments were submitted to histopathological examination in order to analyze the depth of tissue changes, classified as follows: Group A - endothelium and media; Group B - endothelium, media and adventitia. RESULTS: The intensity of histological changes - Groups A and B - that occur in the fragments were proportional to Energy Intensity of electrocauterization (p=0.0001), Power (p=0.017) and Time of Application (p=0.0001). The Spearman correlation coefficient was more powerful for the variable Time of Application: 0.42269 (p=0.002) when compared with the variable Power of Energy (P): 0.3542 (p=0.005). CONCLUSION: Time of Application of Energy is a stronger predictor than the Power of Energy in determining the depth of the histological effects observed in the wall of the varicose vein submitted to electrocauterization.
varicose veins; endovascular procedures; catheter ablation