TY - JOUR
AU1 - Hasenkam, J Michael
AB - Surgical technique, Biomechanical tissue properties, Suture deployment forces, Prosthesis–tissue interaction The article from Lim et al. in the current issue of EJCTS is an eye opener for the very basics of surgery. As surgeons we all know that sutures must be tied appropriately: not too loose and not too tight. We teach our young surgeons how to do it right by hands-on practice. If you tie the knots too tight they will either cut through the tissue or cause necrosis and lead to delayed dehiscence of, e.g. an annular ring as the authors investigated here. Auto mechanics use torque wrenches to ensure tight sealing of a top gasket on an engine’s cylinder head by mounting bolts correctly, reproducibly and uniformly. Admittedly, cardiac surgery is more complex than tight sealing of 2 metal blocks. However, in contrast to mechanics we do not, as cardiac surgeons, have an objective measure for how tight we make our knots for deployment of a heart valve or annuloplasty ring. Cardiac surgery is an art. We base everything on fingertip feeling, experience understanding of what kind of tissue and prosthetic material we work with. We all experience sutures tearing through the tissue in the operating field when we tie the knots too tightly, and we see late valve or annuloplasty ring dehiscence, and acknowledge that flawed surgical technique is a main factor in these complications. We can enhance our artistic skills and enhance our experience to reduce complications—and thereby leave surgery in the hands of the experienced. Why not take the route as indicated by Lim et al. and strive to objectivize the very basic surgical element of tying our knots correctly and thereby improve the surgical outcome? It is a long and winding road, starting with very basic assessment of what we do and how reproducibly we do it. We have a feeling of what is the correct force for tying a knot in a given situation, but today, we cannot quantitate this force in the operating room. The skills possessed by the surgical artist are difficult to disseminate to other colleagues; it is difficult to quantitate how much suturing technique determines the level of success with our surgical technique. It becomes complex when we assess the completeness of sealing between cardiac tissue and prosthetic material. What happens during the healing process? The tissue changes it material characteristics over time. The same goes for the implanted material; but we do not know the time course of these processes. We have a feeling and an experience, and we can measure the hard clinical outcomes on our patients. The mechanical characteristics both intra-and postoperatively is so far a black box, where we can speculate and use our artistic understanding to interpret what happens, when we are successful and what has happened when we fail. Lim et al. applies a force measuring tool [1] which has been available to us for quite some years, predominantly as an experimental research tool [2, 3]. These experimental tools have given us a basic understanding about the level of forces, which the cardiac tissues are exposed to, during and after a surgical intervention [4]. However, we are still at the foot of the mountain. Understanding the forces which tissue is exposed to is not only important knowledge for surgical technique and products. All functional tissue have unique biomechanical characteristics, which is adapted to their particular function (e.g. tendons, muscle, vessels). From basic physiology, we have learned and understand fairly much about tissue strength, elasticity, etc., from composition of collagen, vascularity and other cellular structures. Various disease processes, which lead our patients to treatment, are very often a reflection of alteration in biomechanical properties (vessel stenosis, valve degeneration, aneurysm ruptures). These disease processes enhance the complexity for understanding how diseases develop, how they should be prevented and timing and procedure for intervention. It is a simplistic approach to look at material characteristics in isolation. There are many other elements into understanding and performing our art of surgery. However, we do have tools to measure and interpret the impact of forces acting on biologic and prosthetic material. It is important to acknowledge these instruments and use them to advance surgery. In the relation to the quantitation of tissue and prosthetic material characteristics, animal experiments offer fantastic opportunities for force measurements in human compatible settings. Surgical procedures can be made in a reproducible way and both tissue and prosthetic material can be harvested at predetermined intervals. It is also possible to perform invasive, extensive and time-consuming measurements, which cannot be made in clinical settings. We need to travel much further along the winding road to convey training to our young surgeons and teach them how to handle sutures, instruments and prosthetic material. We also need a quantitative approach to assess our surgical technique and strive to improve the treatment we offer our patients. We also need baseline information about force, wear and tear for assessment and introduction of new surgical products in order to introduce them appropriately. The experimental study by Lim et al. is not unique in terms of tools or product, but it is an additional easy-to-understand eye opener for cardiac surgeons to climb the mountain of detailed and quantitative understanding of our surgical technique and the products we use. There is a mountain of work ahead of us. REFERENCES 1 Lim JH , Shin H , Shin DA , Kim DH , Sohn SK et al. Suture tie-down forces and cyclic contractile forces after an undersized tricuspid annuloplasty using three-dimensional rigid ring: ovine model experiment . Eur J Cardiothorac Surg , in this issue. Google Scholar Google Preview OpenURL Placeholder Text WorldCat COPAC 2 Jensen MO , Jensen H , Honge JL , Nygaard H , Hasenkam JM , Nielsen SL. External approach to in vivo force measurement on mitral valve traction suture . J Biomech 2012 ; 45 :2012: 908 – 12 . Google Scholar Crossref Search ADS PubMed WorldCat 3 Bechsgaard T , Lindskow T , Lading T , Hasenkam JM , Røpcke DM , Nygaard H et al. Biomechanical characterization of the native porcine aortic root . J Biomech 2018 ; 74 : 156 – 62 . Google Scholar Crossref Search ADS PubMed WorldCat 4 Benhassen LL , Røpcke DM , Lading T , Skov JK , Bechsgaard T , Skov SN et al. Asymmetric dynamics of the native aortic annulus evaluated by force transducer and sonomicrometry in a porcine model . Cardiovasc Eng Technol 2019 ; 10 : 482 – 9 . Google Scholar Crossref Search ADS PubMed WorldCat © The Author(s) 2021. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model)
TI - An evolution from the art of cardiac surgery to science-based objective measures for crucial elements in surgical procedures
JF - European Journal of Cardio-Thoracic Surgery
DO - 10.1093/ejcts/ezab263
DA - 2021-05-31
UR - https://www.deepdyve.com/lp/oxford-university-press/an-evolution-from-the-art-of-cardiac-surgery-to-science-based-fILxc4jAUp
SP - 1
EP - 1
VL - Advance Article
IS - 
DP - DeepDyve
ER -