Precision and targeted therapy in cardiac surgery
Editorial

Precision and targeted therapy in cardiac surgery

Ali Fatehi Hassanabad, Paul W. M. Fedak

Department of Cardiac Science, Section of Cardiac Surgery, Cumming School of Medicine, University of Calgary, Libin Cardiovascular Institute of Alberta, Calgary, Alberta, Canada

Correspondence to: Paul W. M. Fedak, MD, PhD. Department of Cardiac Science, Section of Cardiac Surgery, Cumming School of Medicine, University of Calgary, Libin Cardiovascular Institute of Alberta, C880, 1403-29 Street NW, Calgary, Alberta T2N 2T9, Canada. Email: paul.fedak@gmail.com.

Comment on: Gulack BC, Kirkwood KA, Shi W, et al. Secondary surgical-site infection after coronary artery bypass grafting: A multi-institutional prospective cohort study. J Thorac Cardiovasc Surg 2018;155:1555-62.e1.


Submitted Aug 17, 2018. Accepted for publication Sep 12, 2018.

doi: 10.21037/jtd.2018.09.90


With more than 300,000 cases being performed annually in the United States alone, a coronary artery bypass grafting (CABG) is the preferred method for revascularization for most patients that are suffering from a multivessel coronary artery disease or diabetes (1). Secondary to its long term patency and survival benefits, if suitable and surgically feasible, the left internal mammary artery remains the conduit of choice for the bypassing of the left anterior descending coronary artery (2). Moreover, the use of a second arterial conduit, whether it is the right internal mammary artery or a radial artery, has gained increased attention since the 1990’s. This is due to the practices varying greatly in this time-period, due to the perceived conflicting ideas about the long-term outcomes about a total arterial revascularization in a coronary artery procedure (3). Nevertheless, the great saphenous vein remains the most widely used conduit for a coronary artery bypass surgery. There are some factors that make the great saphenous vein a compelling option. For example, harvesting is relatively easy, it is readily available in most cases, it is resistant to spasm, and its patency has been extensively studied (1,4).

The traditional method for harvesting the great saphenous vein involves making a large incision on the patient’s leg. Unsurprisingly, this incision is associated with more pain, which can result in a less and more delayed mobility and ambulation, thereby prolonging hospitalization. I is also associated with wound complications such as an including infection or an aesthetically unappealing scar (1). With this method, wound complications are typically seen in about 2–24% of the cases, conferring a significant health and economic burden (5). After the development of the endoscopy as a new technology for surgery in the 1990’s, endoscopic vein harvesting was incorporated in cardiac surgery to address some of the challenges of a traditional open vein harvesting. In the ensuing years, endoscopic vein harvesting has rapidly grown in popularity with many centres across the world, adopted as the primary option. A prospective randomized parallel-group trial demonstrated that endoscopic vein harvesting was associated with a lower amount of post-surgical complications when it was compared to the traditional open vein harvesting method (5).

In this multi-centre prospective cohort study, Gulack et al. analyzes the patient risk factors and processes of care which are associated with a secondary surgical-site infection (SSI) after coronary artery bypass surgery. The authors should be applauded for conducting the study, and addressing an important issue in cardiac surgery. The study has a few strengths; for example, a large sample size of 2,714 patients, as well as having a clear, comprehensive, and elegant design. It also has an impressive follow-up completion rate of 98%, and appropriate statistical analysis to go along with it all. Gulack and colleagues have acknowledged that the study was not powered to examine the endpoint of SSI, so its predictive power is limited. They also highlight that the follow-up duration of 65 days may have been too short for fully identifying patients who had developed an SSI post CABG. By virtue of the data available for this cohort study, it was unfortunate that the authors were not able to capture more details; such as technique of open vein harvest or whether or not an endoscopic vein harvest was initially planned. Nevertheless, their results had showed there was a 3% increase in the rate for being afflicted by a secondary SSI, which the study had associated this increase with an increased body mass index and packed red blood cell transfusion. Interestingly enough, this study didn’t find any increase in post-operative hyperglycemia when determining the risk-factors for acquiring an SSI.

Like other studies of its kind, Gulack et al. highlight the main advantages of endoscopic vein harvesting technique which is reducing the wound area. This leads to the improved cosmetic outcomes and the lowered incidence of a lower limb morbidity rate which is related to wound infection, hematoma, seroma, lymphedema, lymphorrhea, saphenous neuropathy and neuralgia. In the grand scheme of things, it is suggested that these benefits also maintain the cost-effectiveness of endoscopic vein harvesting (6). Despite this, endoscopic vein harvesting has not been free of controversy, as some groups have suggested a lower graft patency for intermediate all the way to long-term follow up studies. They have attributed this compromised outcome to the endothelial damage elicited by using a scope (7-10). On the other hand, there are different types of studies which have illustrated the safety of endoscopic vein harvesting, and have dismissed the concerns regarding a higher graft patency failure rate (11-14). In reality, graft patency rates can probably be mediated in endoscopic vein harvesting by an experienced user. However, more studies, with more of particularly randomized controlled trials, are needed to fully assess the clinical outcomes of endoscopic versus open vein harvesting (15,16).

To further aid patient recovery post cardiac surgery, our group assessed the safety and efficacy of prophylactic negative pressure wound therapy (NPWT) following an open saphenous vein harvest in cardiac surgery (17). This single-centre, single-blind, randomized controlled trial considered 64 patients undergoing CABG, and assessed the rates of surgical site infection as one its secondary endpoints. We were able to show that NPWT following saphenous vein graft harvesting is safe, well-tolerated, and its utility improves the post-operative recovery time, with a prolonged impact on mobility at six weeks.

With the advent and exponential growth of the newer minimally invasive techniques, a lot of excitement has been generated for incorporating such newer approaches in cardiac surgery. Many studies are investigating the safety of these approaches, and a variety of groups are aiming to demonstrate the superiority these innovations can confer in optimal patient care. These methods will undoubtedly shape the future landscape of cardiac surgery as a profession, but as is the case for any intervention, every procedure should be considered in the context of what is most beneficial to the patient. To ensure a technology or technique has a lasting and meaningful impact, this consideration should be driven by evidence based practices which have been targeted for the precise individualized application of medicine.


Acknowledgements

None.


Footnote

Conflicts of Interest: The authors have no conflicts of interest to declare.


References

  1. Nezafati P, Kahrom M, Nezafati MH. Endoscopic vein harvesting: the growing role in cardiac surgery. Arch Med Sci Atheroscler Dis 2017;2:e34-6. [Crossref] [PubMed]
  2. Likosky DS, Dacey LJ. To use or not to use: a focus on endoscopic vein harvesting. Future Cardiol 2011;7:277-80. [Crossref] [PubMed]
  3. Gaudino M, Mack MJ, Taggart DP. Additional Arterial Conduits in Coronary Artery Bypass Surgery: Finally Coming of Age. J Am Coll Cardiol 2018;71:2974-6. [Crossref] [PubMed]
  4. Hess CN, Lopes RD, Gibson CM, et al. Saphenous vein graft failure after coronary artery bypass surgery: insights from PREVENT IV. Circulation 2014;130:1445-51. [Crossref] [PubMed]
  5. Chernyavskiy A, Volkov A, Lavrenyuk O, et al. Comparative results of endoscopic and open methods of vein harvesting for coronary artery bypass grafting: a prospective randomized parallel-group trial. J Cardiothorac Surg 2015;10:163. [Crossref] [PubMed]
  6. Hussaini BE, Lu XG, Wolfe JA, et al. Evaluation of endoscopic vein extraction on structural and functional viability of saphenous vein endothelium. J Cardiothorac Surg 2011;6:82. [Crossref] [PubMed]
  7. Eid RE, Wang L, Kuzman M, et al. Endoscopic versus open saphenous vein graft harvest for lower extremity bypass in critical limb ischemia. J Vasc Surg 2014;59:136-44. [Crossref] [PubMed]
  8. Harky A, Balmforth D, Shipolini A, et al. Is endoscopic long saphenous vein harvesting equivalent to open harvesting technique in terms of graft patency? Interact Cardiovasc Thorac Surg 2017;25:323-6. [Crossref] [PubMed]
  9. Kopjar T, Dashwood MR. Endoscopic Versus "No-Touch" Saphenous Vein Harvesting for Coronary Artery Bypass Grafting: A Trade-Off Between Wound Healing and Graft Patency. Angiology 2016;67:121-32. [Crossref] [PubMed]
  10. Lopes RD, Hafley GE, Allen KB, et al. Endoscopic versus open vein-graft harvesting in coronary-artery bypass surgery. N Engl J Med 2009;361:235-44. [Crossref] [PubMed]
  11. Deppe AC, Liakopoulos OJ, Choi YH, et al. Endoscopic vein harvesting for coronary artery bypass grafting: a systematic review with meta-analysis of 27,789 patients. J Surg Res 2013;180:114-24. [Crossref] [PubMed]
  12. Krishnamoorthy B, Critchley WR, Thompson AJ, et al. Study Comparing Vein Integrity and Clinical Outcomes in Open Vein Harvesting and 2 Types of Endoscopic Vein Harvesting for Coronary Artery Bypass Grafting: The VICO Randomized Clinical Trial (Vein Integrity and Clinical Outcomes). Circulation 2017;136:1688-702. [Crossref] [PubMed]
  13. Luckraz H, Cartwright C, Nagarajan K, et al. Major adverse cardiac and cerebrovascular event and patients' quality of life after endoscopic vein harvesting as compared with open vein harvest (MAQEH): a pilot study. Open Heart 2018;5:e000694. [Crossref] [PubMed]
  14. Nezafati MH, Nezafati P, Amoueian S, et al. Immunohistochemistry comparing endoscopic vein harvesting vs. open vein harvesting on saphenous vein endothelium. J Cardiothorac Surg 2014;9:101. [Crossref] [PubMed]
  15. Grant SW, Grayson AD, Zacharias J, et al. What is the impact of endoscopic vein harvesting on clinical outcomes following coronary artery bypass graft surgery? Heart 2012;98:60-4. [Crossref] [PubMed]
  16. Raja SG, Sarang Z. Endoscopic vein harvesting: technique, outcomes, concerns & controversies. J Thorac Dis 2013;5 Suppl 6:S630-7. [PubMed]
  17. Lee AJ, Sheppard CE, Kent WD, et al. Safety and efficacy of prophylactic negative pressure wound therapy following open saphenous vein harvest in cardiac surgery: a feasibility study. Interact Cardiovasc Thorac Surg 2017;24:324-8. [PubMed]

(English Language Editor: Jeremy Dean Chapnick, AME Publishing Company)

Cite this article as: Fatehi Hassanabad A, Fedak PW. Precision and targeted therapy in cardiac surgery. J Thorac Dis 2018;10(Suppl 33):S3986-S3988. doi: 10.21037/jtd.2018.09.90