OBJECTIVE: To compare the free blood flow, caliber, and length of the left internal thoracic artery (LITA), dissected in the pedicled (P) and skeletonized (S) manners, during surgery before and after topical vasodilator (TV) application. METHODS: A randomized, blind, clinical trial was carried out with 50 patients undergoing elective myocardial revascularization to assess the use of the LITA in situ in its pedicled or skeletonized form. The 25 patients in the pedicled group (GP) had NYHA class II or III angina, ejection fraction (EF) of 50.8±9.2%, and 16 were of the male sex. The patients in the skeletonized group (SG) had NYHA class II angina, EF of 46.8±9.3%, and 19 were of the male sex. The measurements were performed before extracorporeal circulation and divided into 2 phases: phase 1 (before topical papaverine application) and phase 2 (15 min after topical application of papaverine, 2.5 mg/mL, at 37ºC). During the measurements, mean blood pressure, central venous pressure, and heart rate were monitored. RESULTS: The phase 1 and 2 results are as follows: 1) PG: blood flow, 46±16 and 77±28 mL/min; caliber, 1.4±0.1 and 1.7±0.1 mm, respectively; 2) SG: blood flow, 57±27 and 97±35 mL/min; and caliber, 1.4±0.1 and 1.8±0.2 mm, respectively. No significant differences were observed in length. CONCLUSION: The LITA in SG had a significant increase in blood flow and caliber after the use of TV compared with blood flow and caliber in PG (P=0.03 and P=0.01, respectively).