Skeletonized vs Pedicled Internal Mammary Artery Graft Harvesting in Coronary Artery Bypass Surgery
Authors: André Lamy, Austin Browne, Tej Sheth, Zhe Zheng, François Dagenais, Nicolas Noiseux, Xin Chen, Faisal G. Bakaeen, Miroslav Brtko, Louis-Mathieu Stevens, Mariam Alboom, Shun Fu Lee, Ingrid Copland, Yusuf Salim, John Eikelboom, Rafael Diaz, Andrew M. Tonkin, John D. Varigos, Peter B. Verhamme, Alvaro Avezum, Leopoldo S. Piegas, Gilles R. Dagenais, Eva M. Lonn, Fernando Lanas, Jun Zhu, Lisheng Liu, Yan Liang, Patricio Lopez-Jaramillo, Petr Widimsky, Christian Torp-Pedersen, Camilo Felix, Kaj P. Metsarinne, Philippe Gabriel Steg, Victor Aboyans, Georg Ertl, Stefan Stoerk, Katalin Keltai, Matyas Keltai, Martin O'Donnell, Keith A. Fox, Ajay Kakkar, Basil S. Lewis, Aldo P. Maggioni, Masatsugu Hori, Khalid Yusoff, Marco Alings, Antonio L. Dans, Tomasz J. Guzik, Dragos Vinereanu, Nana Goar Pogosova, Patrick J. Commerford, Jae-Hyung Kim, Lars Ryden, Alexander N. Parkhomenko, Deepak L. Bhatt, Kelley R.H. Branch, Jeffrey L. Probstfield, Sonia Anand, Jackie Bosch, Stuart Connolly, John W. Eikelboom, Robert Hart, Andre Lamy, Paul Moayeddi, Mike Sharma, Salim Yusuf, Scott Berkowitz, Eva Muehlhofer
Journal: JAMA Cardiology (2021)

<h3>Importance</h3> The relative safety and patency of skeletonized vs pedicled internal mammary artery grafts in patients undergoing coronary artery bypass graft (CABG) surgery are unknown. <h3>Objective</h3> To investigate the association of skeletonized vs pedicled harvesting with internal mammary artery graft patency and clinical outcomes 1 year after CABG surgery. <h3>Design, Setting, and Participants</h3> This study was a post hoc analysis of the multicenter, randomized, double-blind, placebo-controlled Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) clinical trial, which enrolled 27 395 patients from 602 centers in 33 countries from March 2013 through May 2016. Eligibility criteria for the trial included CABG surgery for coronary artery disease with at least 2 grafts implanted and an estimated glomerular filtration rate of at least 30 mL/min. A total of 1002 of 1448 patients were randomized to the CABG arm of the COMPASS trial and underwent skeletonized (282 [28.1%]) or pedicled (720 [71.9%]) internal mammary artery harvesting. The patients had evaluable angiography results 1 year after surgery. Data were analyzed from October 11, 2019, to May 14, 2020. <h3>Interventions</h3> Patients underwent graft harvesting with either the pedicled technique or skeletonized technique. <h3>Main Outcomes and Measures</h3> The primary outcome was graft occlusion 1 year after CABG surgery, as assessed by computed tomography angiography. <h3>Results</h3> A total of 1002 patients underwent skeletonized (282 [28.1%]; mean [SD] age, 65.9 [8.1] years; 229 men [81.2%]; 194 White patients [68.8%]) or pedicled (720 [71.9%]; mean [SD] age, 64.8 [7.6] years; 603 men [83.8%]; 455 White patients [63.2%]) internal mammary artery harvesting. Rates of internal mammary artery graft occlusion 1 year after CABG surgery were higher in the skeletonized group than in the pedicled group (33 of 344 [9.6%] vs 30 of 764 [3.9%]; graft-level adjusted odds ratio, 2.41; 95% CI, 1.39-4.20;<i>P</i> = .002), including the left internal mammary artery to left anterior descending artery (21 of 289 [7.3%] vs 25 of 725 [3.4%]; graft-level adjusted odds ratio, 2.10; 95% CI, 1.14-3.88,<i>P</i> = .02). After a mean follow-up of 23 months, skeletonized graft harvesting was also associated with a higher rate of major adverse cardiovascular events (20 [7.1%] vs 15 [2.1%]; adjusted hazard ratio, 3.19; 95% CI, 1.53-6.67;<i>P</i> = .002) and repeated revascularization (14 [5.0%] vs 10 [1.4%]; adjusted hazard ratio, 2.75; 95% CI, 1.10-6.88;<i>P</i> = .03). <h3>Conclusions and Relevance</h3> This post hoc analysis of the COMPASS randomized clinical trial found that harvesting of the internal mammary artery during CABG surgery using a skeletonized technique was associated with a higher rate of graft occlusion and worse clinical outcomes than the traditional pedicled technique. Future randomized clinical trials are needed to establish the safety and patency of the skeletonized technique. <h3>Trial Registration</h3> ClinicalTrials.gov Identifier:NCT01776424