Internal mammary artery harvesting using the harmonic scalpel

Internal mammary artery (IMA) harvesting using the harmonic scalpel (HS) was recently introduced. We studied 541 IMAs harvested by the same surgeon through a standard median sternotomy in 472 coronary bypass patients; 252 (47%) with the HS, while 289 (53%) were with electrocautery (EC). Patient demographics included mean ages: 67 years HS vs. 65 years EC (p = NS); male:female ratio: 3:1; and insulin dependent diabetes mellitus (IDDM): 11% HS vs. 12.5% EC (NS). Mean ultrasonic IMA flow at a mean SBP of 70 mm Hg in 10 consecutive patients of each group were: preharvest, HS 11.9 +/- 2.3 ml/min vs. EC 8.5 +/- 1.6 ml/min (p = 0.256); postharvest, HS 35.7 +/- 10.7 ml/min vs. EC 22 +/- 2.9 ml/min (0.235); and postcardiopulmonary bypass (post-CPB), HS 47.8 +/- 6.2 ml/min vs. EC 41.7 +/- 2.5 ml/min (0.381). Histologic samples of 50 consecutive IMAs showed no evidence of vessel injury in either group. Clinical results revealed postoperative bleeding in 6/217 (2.7%) HS vs. 7/255 (2.7%) EC (p = 0.783), none attributed to bleeding from the IMA; phrenic paresis: 0/217 in HS but 1/255 (0.4%) in EC (p = 0.960); sternal wound infection: 5/217 (2.3%) HS vs. 6/255 (2.4%) EC (p = 0.787); postoperative IABP: 6/217 (2.7%) HS vs. 5/255 (2%) EC (p = 0.859); mortality: 2/217 (0.9%) HS vs. 2/255 (0.8%) EC (p = 0.710). Hemodynamic, histologic, and clinical results were comparable in both groups. The authors believe the HS is safe and effective for IMA harvesting.