1
|
Montelione N, Catanese V, Nenna A, Gabellini T, Ferrisi C, Paolini J, Ciolli A, Barillà D, Loreni F, Chello M, Spinelli F, Stilo F. External Scaffold for Venous Graft to Treat Chronic Limb-Threatening Ischemia: Results of the FRAME Vascular Support. J Clin Med 2024; 13:2095. [PMID: 38610860 PMCID: PMC11012784 DOI: 10.3390/jcm13072095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 03/22/2024] [Accepted: 03/30/2024] [Indexed: 04/14/2024] Open
Abstract
Background: The surgical treatment of chronic limb-threatening ischemia and optimal conduit choice are extensively debated. The presence of suboptimal autologous material, such as varicosities or venous aneurysms, might impair long-term outcomes. Therefore, kink-resistant external supports have been advocated in the recent literature to improve the conduit quality and outcomes. This study analyzes the FRAME external support in venous ectasic grafts in patients with chronic limb-threatening ischemia. Methods: From September 2017 to September 2023, a total of sixteen patients underwent CLTI surgery with FRAME external support for venous grafts. The inclusion criteria for FRAME applications were varicose or ectasic autologous material with a diameter ≥ 4.5 and ≤ 8 mm in an isolated segment or in the entire vein and a higher risk of bypass extrinsic compression (e.g., extra-anatomical venous bypass course). Results: Technical success and intraoperative patency were achieved in all cases. At 30 days, the limb salvage and survival rates were 100%. The primary bypass patency was 93.7% due to an early graft occlusion. No graft infection was registered. In one case, dehiscence of the surgical wound was treated by surgical debridement and antibiotic therapy. Minor amputation was required in four patients. Over a median follow-up of 32 months, two occlusions were observed; one was treated with reoperation and the other with major amputation. The primary patency was 68.7% and the assisted primary patency was 75%. Limb salvage rates observed during the entire follow-up period were 87.5%. No graft infections or dilatation of the reinforced veins were registered. Conclusions: For patients with CLTI undergoing infrainguinal bypass, satisfactory results in terms of patency and limb salvage rates were achieved using the autologous venous material, even if ectasic or varicose, with the vascular external support FRAME.
Collapse
Affiliation(s)
- Nunzio Montelione
- Vascular Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (N.M.); (V.C.); (T.G.); (J.P.); (A.C.); (F.S.); (F.S.)
| | - Vincenzo Catanese
- Vascular Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (N.M.); (V.C.); (T.G.); (J.P.); (A.C.); (F.S.); (F.S.)
| | - Antonio Nenna
- Cardiac Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (C.F.); (F.L.)
| | - Teresa Gabellini
- Vascular Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (N.M.); (V.C.); (T.G.); (J.P.); (A.C.); (F.S.); (F.S.)
- Vascular Surgery Residency Program, University of Ferrara, 44124 Ferrara, Italy
| | - Chiara Ferrisi
- Cardiac Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (C.F.); (F.L.)
- Cardiac Surgery Residency Program, Università Campus Bio-Medico di Roma, 00128 Rome, Italy
| | - Julia Paolini
- Vascular Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (N.M.); (V.C.); (T.G.); (J.P.); (A.C.); (F.S.); (F.S.)
- Vascular Surgery Residency Program, Università Cattolica del Sacro Cuore, 00128 Rome, Italy
| | - Alessandro Ciolli
- Vascular Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (N.M.); (V.C.); (T.G.); (J.P.); (A.C.); (F.S.); (F.S.)
- Vascular Surgery Residency Program, Università Cattolica del Sacro Cuore, 00128 Rome, Italy
| | - David Barillà
- Vascular Surgery, Humanitas Clinical and Research Center—IRCCS, Rozzano, 20148 Milan, Italy
| | - Francesco Loreni
- Cardiac Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (C.F.); (F.L.)
- Cardiac Surgery Residency Program, Università Campus Bio-Medico di Roma, 00128 Rome, Italy
| | - Massimo Chello
- Cardiac Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (C.F.); (F.L.)
| | - Francesco Spinelli
- Vascular Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (N.M.); (V.C.); (T.G.); (J.P.); (A.C.); (F.S.); (F.S.)
| | - Francesco Stilo
- Vascular Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (N.M.); (V.C.); (T.G.); (J.P.); (A.C.); (F.S.); (F.S.)
| |
Collapse
|
2
|
Russu E, Arbanasi EM, Chirila TV, Muresan AV. Therapeutic strategies based on non-ionizing radiation to prevent venous neointimal hyperplasia: the relevance for stenosed arteriovenous fistula, and the role of vascular compliance. Front Cardiovasc Med 2024; 11:1356671. [PMID: 38374996 PMCID: PMC10875031 DOI: 10.3389/fcvm.2024.1356671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 01/23/2024] [Indexed: 02/21/2024] Open
Abstract
We have reviewed the development and current status of therapies based on exposure to non-ionizing radiation (with a photon energy less than 10 eV) aimed at suppressing the venous neointimal hyperplasia, and consequentially at avoiding stenosis in arteriovenous grafts. Due to the drawbacks associated with the medical use of ionizing radiation, prominently the radiation-induced cardiovascular disease, the availability of procedures using non-ionizing radiation is becoming a noteworthy objective for the current research. Further, the focus of the review was the use of such procedures for improving the vascular access function and assuring the clinical success of arteriovenous fistulae in hemodialysis patients. Following a brief discussion of the physical principles underlying radiotherapy, the current methods based on non-ionizing radiation, either in use or under development, were described in detail. There are currently five such techniques, including photodynamic therapy (PDT), far-infrared therapy, photochemical tissue passivation (PTP), Alucent vascular scaffolding, and adventitial photocrosslinking. The last three are contingent on the mechanical stiffening achievable by the exogenous photochemical crosslinking of tissular collagen, a process that leads to the decrease of venous compliance. As there are conflicting opinions on the role of compliance mismatch between arterial and venous conduits in a graft, this aspect was also considered in our review.
Collapse
Affiliation(s)
- Eliza Russu
- Clinic of Vascular Surgery, Mures County Emergency Hospital, Targu Mures, Romania
- Department of Vascular Surgery, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
| | - Emil-Marian Arbanasi
- Clinic of Vascular Surgery, Mures County Emergency Hospital, Targu Mures, Romania
- Department of Vascular Surgery, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
- Doctoral School of Medicine and Pharmacy, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
- Centre for Advanced Medical and Pharmaceutical Research (CCAMF), George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
| | - Traian V. Chirila
- Centre for Advanced Medical and Pharmaceutical Research (CCAMF), George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
- Queensland Eye Institute, Woolloongabba, QLD, Australia
- Faculty of Medicine, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
- School of Chemistry and Physics, Queensland University of Technology, Brisbane, QLD, Australia
- Australian Institute of Bioengineering and Nanotechnology (AIBN), University of Queensland, St Lucia, QLD, Australia
| | - Adrian V. Muresan
- Clinic of Vascular Surgery, Mures County Emergency Hospital, Targu Mures, Romania
- Department of Vascular Surgery, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures, Targu Mures, Romania
| |
Collapse
|
3
|
Fashina O, Abbasciano RG, McQueen LW, Ladak S, George SJ, Suleiman S, Punjabi PP, Angelini GD, Zakkar M. Large animal model of vein grafts intimal hyperplasia: A systematic review. Perfusion 2022:2676591221091200. [PMID: 35624557 DOI: 10.1177/02676591221091200] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Coronary artery bypass grafting remains the treatment of choice for a large cohort of patients with significant coronary disease. Despite the increased use of arterial grafts, the long saphenous vein remains the most commonly used conduit. Long-term graft patency continues to be the Achilles heel of saphenous vein grafts. This is due to the development of intimal hyperplasia, a chronic inflammatory disease that results in the narrowing and occlusion of a significant number of vein grafts. Research models for intimal hyperplasia are essential for a better understanding of pathophysiological processes of this condition. Large animal models resemble human anatomical structures and have been used as a surrogate to study disease development and prevention over the years. In this paper, we systematically review all published studies that utilized large animal models of vein graft disease with a focus on the type of model and any therapeutic intervention, specifically the use of external stents/mesh.
Collapse
Affiliation(s)
- Oluwatomini Fashina
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, UK
| | - Riccardo G Abbasciano
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, UK
| | - Liam W McQueen
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, UK
| | - Shameem Ladak
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, UK
| | - Sarah J George
- Bristol Heart Institute and Translational Biomedical Research Centre, Bristol Medical School, University of Bristol, Bristol Royal Infirmary, Bristol, UK
| | - Sadeeh Suleiman
- Bristol Heart Institute and Translational Biomedical Research Centre, Bristol Medical School, University of Bristol, Bristol Royal Infirmary, Bristol, UK
| | - Prakash P Punjabi
- Department of Cardiovascular Sciences, Imperial College, Hammersmith Hospital, London, UK
| | - Gianni D Angelini
- Bristol Heart Institute and Translational Biomedical Research Centre, Bristol Medical School, University of Bristol, Bristol Royal Infirmary, Bristol, UK
| | - Mustafa Zakkar
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, UK
| |
Collapse
|
4
|
Yasuda S, Goda M, Shibuya T, Uchida K, Suzuki S, Noishiki Y, Yokoyama U, Ishikawa Y, Masuda M. An appropriately sized soft polyester external stent prevents enlargement and neointimal hyperplasia of a saphenous vein graft in a canine model. Artif Organs 2019; 43:577-583. [DOI: 10.1111/aor.13399] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 11/06/2018] [Accepted: 11/20/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Shota Yasuda
- Department of Surgery Yokohama City University Yokohama Japan
| | - Motohiko Goda
- Department of Surgery Yokohama City University Yokohama Japan
| | - Taisuke Shibuya
- Department of Surgery Yokohama City University Yokohama Japan
| | - Keiji Uchida
- Cardiovascular Center Yokohama City University Medical Center Yokohama Japan
| | - Shinichi Suzuki
- Department of Surgery Yokohama City University Yokohama Japan
| | - Yasuharu Noishiki
- Department of Neurological Anatomy Yokohama City University Yokohama Japan
| | - Utako Yokoyama
- Cardiovascular Research Institute Yokohama City University Yokohama Japan
| | - Yoshihiro Ishikawa
- Cardiovascular Research Institute Yokohama City University Yokohama Japan
| | - Munetaka Masuda
- Department of Surgery Yokohama City University Yokohama Japan
| |
Collapse
|
5
|
Fernández-Alfonso MS, Somoza B, Tsvetkov D, Kuczmanski A, Dashwood M, Gil-Ortega M. Role of Perivascular Adipose Tissue in Health and Disease. Compr Physiol 2017; 8:23-59. [PMID: 29357124 DOI: 10.1002/cphy.c170004] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Perivascular adipose tissue (PVAT) is cushion of fat tissue surrounding blood vessels, which is phenotypically different from other adipose tissue depots. PVAT is composed of adipocytes and stromal vascular fraction, constituted by different populations of immune cells, endothelial cells, and adipose-derived stromal cells. It expresses and releases an important number of vasoactive factors with paracrine effects on vascular structure and function. In healthy individuals, these factors elicit a net anticontractile and anti-inflammatory paracrine effect aimed at meeting hemodynamic and metabolic demands of specific organs and regions of the body. Pathophysiological situations, such as obesity, diabetes or hypertension, induce changes in its amount and in the expression pattern of vasoactive factors leading to a PVAT dysfunction in which the beneficial paracrine influence of PVAT is shifted to a pro-oxidant, proinflammatory, contractile, and trophic environment leading to functional and structural cardiovascular alterations and cardiovascular disease. Many different PVATs surrounding a variety of blood vessels have been described and exhibit regional differences. Both protective and deleterious influence of PVAT differs regionally depending on the specific vascular bed contributing to variations in the susceptibility of arteries and veins to vascular disease. PVAT therefore, might represent a novel target for pharmacological intervention in cardiovascular disease. © 2018 American Physiological Society. Compr Physiol 8:23-59, 2018.
Collapse
Affiliation(s)
| | - Beatriz Somoza
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad CEU-San Pablo, Madrid, Spain
| | - Dmitry Tsvetkov
- Department of Anestesiology, Perioperative and Pain Medicine, HELIOS Klinikum, Berlin-Buch GmbH, Germany.,Institute of Experimental and Clinical Pharmacology and Toxicology, Department of Pharmacology and Experimental Therapy, Eberhard Karls University Hospitals and Clinics, and Interfaculty Center of Pharmacogenomics and Drug Research, Tübingen, Germany
| | - Artur Kuczmanski
- Department of Anestesiology, Perioperative and Pain Medicine, HELIOS Klinikum, Berlin-Buch GmbH, Germany
| | - Mick Dashwood
- Royal Free Hospital Campus, University College Medical School, London, United Kingdom
| | - Marta Gil-Ortega
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad CEU-San Pablo, Madrid, Spain
| |
Collapse
|
6
|
Fernández-Alfonso MS, Gil-Ortega M, Aranguez I, Souza D, Dreifaldt M, Somoza B, Dashwood MR. Role of PVAT in coronary atherosclerosis and vein graft patency: friend or foe? Br J Pharmacol 2017; 174:3561-3572. [PMID: 28150299 DOI: 10.1111/bph.13734] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 01/02/2017] [Accepted: 01/19/2017] [Indexed: 01/18/2023] Open
Abstract
Perivascular adipose tissue (PVAT) releases numerous factors and adipokines with paracrine effects on both vascular structure and function. These effects are variable as they depend on regional differences in PVAT among blood vessels and vary with changes in adiposity. There is considerable evidence demonstrating an association between coronary PVAT and the development and progression of coronary artery disease, which is associated with inflammation, oxidative stress, angiogenesis, vascular remodelling and blood clotting. However, PVAT also has a protective role in vascular grafts, especially the no-touch saphenous vein, in patients undergoing coronary artery bypass. This beneficial influence of PVAT involves factors such as adipocyte-derived relaxing factor, nitric oxide (NO), leptin, adiponectin, prostanoids, hydrogen sulphide and neurotransmitters, as well as mechanical protection. This article aims to highlight and compare the dual role of PVAT in the development and progression of coronary atherosclerosis, as well as in increased graft patency. Different deleterious and protective mechanisms of PVAT are also discussed and the inside-outside signalling paradigm of atherosclerosis development re-evaluated. The bidirectional communication between the arterial and venous wall and their surrounding PVAT, where signals originating from the vascular wall or lumen can affect PVAT phenotype, has been shown to be very complex. Moreover, signals from PVAT also influence the structure and function of the vascular wall in a paracrine manner. LINKED ARTICLES This article is part of a themed section on Molecular Mechanisms Regulating Perivascular Adipose Tissue - Potential Pharmacological Targets? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.20/issuetoc.
Collapse
Affiliation(s)
- M S Fernández-Alfonso
- Instituto Pluridisciplinar and Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - M Gil-Ortega
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad CEU-San Pablo, Madrid, Spain
| | - I Aranguez
- Instituto Pluridisciplinar and Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - D Souza
- Department of Cardiothoracic and Vascular Surgery and University Health Care Research Center, School of Medical Sciences, Örebro University, Örebro, Sweden
| | - M Dreifaldt
- Department of Cardiothoracic and Vascular Surgery and University Health Care Research Center, School of Medical Sciences, Örebro University, Örebro, Sweden
| | - B Somoza
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad CEU-San Pablo, Madrid, Spain
| | - M R Dashwood
- Royal Free Hospital Campus, University College Medical School, London, UK
| |
Collapse
|
7
|
Abstract
Saphenous vein remains a widely used conduit in coronary surgery. However, the long-term success of surgical myocardial revascularization is largely limited by the development of neointimal hyperplasia and superimposed atherosclerosis in vein grafts. Although strategies for preventing vein graft failure have been constantly explored, few therapeutic interventions to date have shown sustained benefits in the clinical setting. The application of external support has emerged as a promising strategy for modulating the overall biomechanical responses in venous wall. Nonetheless, clinical translation of this intervention has been formerly challenged, primarily due to several technique limitations. The purpose of the current review is to summarize the possible mechanisms involved in the external support strategy for preventing vein graft failure. Furthermore, several previously tested biomaterials and delivery techniques are also highlighted.
Collapse
Affiliation(s)
- Jia Hu
- Division of Cardiothoracic Surgery, Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, People's Republic of China
| | | |
Collapse
|
8
|
Muto A, Model L, Ziegler K, Eghbalieh SD, Dardik A. Mechanisms of vein graft adaptation to the arterial circulation: insights into the neointimal algorithm and management strategies. Circ J 2010; 74:1501-1512. [PMID: 20606326 PMCID: PMC3662001 DOI: 10.1253/circj.cj-10-0495] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
For patients with coronary artery disease or limb ischemia, placement of a vein graft as a conduit for a bypass is an important and generally durable strategy among the options for arterial reconstructive surgery. Vein grafts adapt to the arterial environment, and the limited formation of intimal hyperplasia in the vein graft wall is thought to be an important component of successful vein graft adaptation. However, it is also known that abnormal, or uncontrolled, adaptation may lead to abnormal vessel wall remodeling with excessive neointimal hyperplasia, and ultimately vein graft failure and clinical complications. Therefore, understanding the venous-specific pathophysiological and molecular mechanisms of vein graft adaptation are important for clinical vein graft management. Of particular importance, it is currently unknown whether there exist several specific distinct molecular differences in the venous mechanisms of adaptation that are distinct from arterial post-injury responses; in particular, the participation of the venous determinant Eph-B4 and the vascular protective molecule Nogo-B may be involved in mechanisms of vessel remodeling specific to the vein. This review describes (1) venous biology from embryonic development to the mature quiescent state, (2) sequential pathologies of vein graft neointima formation, and (3) novel candidates for strategies of vein graft management. Scientific inquiry into venous-specific adaptation mechanisms will ultimately provide improvements in vein graft clinical outcomes.
Collapse
Affiliation(s)
- Akihito Muto
- Interdepartmental Program in Vascular Biology and Therapeutics
- the Section of Vascular Surgery, Yale University School of Medicine, New Haven, CT
| | - Lynn Model
- Interdepartmental Program in Vascular Biology and Therapeutics
- the Section of Vascular Surgery, Yale University School of Medicine, New Haven, CT
| | - Kenneth Ziegler
- Interdepartmental Program in Vascular Biology and Therapeutics
- the Section of Vascular Surgery, Yale University School of Medicine, New Haven, CT
| | - Sammy D.D. Eghbalieh
- Interdepartmental Program in Vascular Biology and Therapeutics
- St. Mary's Hospital, Waterbury, CT
| | - Alan Dardik
- Interdepartmental Program in Vascular Biology and Therapeutics
- the Section of Vascular Surgery, Yale University School of Medicine, New Haven, CT
- the VA Connecticut Healthcare System, West Haven, CT
| |
Collapse
|
9
|
Arvela E, Kauhanen P, Albäck A, Lepäntalo M, Neufang A, Adili F, Schmitz-Rixen T. Initial Experience with a New Method of External Polyester Scaffolding for Infrainguinal Vein Grafts. Eur J Vasc Endovasc Surg 2009; 38:456-62. [DOI: 10.1016/j.ejvs.2009.05.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2009] [Accepted: 05/24/2009] [Indexed: 11/29/2022]
|
10
|
Human P, Franz T, Scherman J, Moodley L, Zilla P. Dimensional analysis of human saphenous vein grafts: Implications for external mesh support. J Thorac Cardiovasc Surg 2009; 137:1101-8. [PMID: 19379974 DOI: 10.1016/j.jtcvs.2008.10.040] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 09/05/2008] [Accepted: 10/03/2008] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Constrictive external mesh support of vein grafts was shown to mitigate intimal hyperplasia in animal experiments. To determine the degree of constriction required for the elimination of dimensional irregularities in clinically used vein grafts, a detailed anatomic study of human saphenous veins was conducted. METHODS In 200 consecutive patients having coronary artery bypass grafting, harvested saphenous veins (length 34.4 +/- 10.8 cm) were analyzed regarding diameter irregularities, side branch distribution, and microstructure. RESULTS The mean outer diameter of surgically distended saphenous veins was 4.2 +/- 0.6 mm (men, 4.3 +/- 0.6 mm vs women, 3.9 +/- 0.5 mm; P < .0001). Although the outer diameter significantly decreased over the initial 18 cm (-7.6%; P < .0001), the overall increase between malleolus and thigh was not significant (+11.2%). Smaller-diameter veins (<3.5 mm) had more pronounced diameter fluctuations than larger veins (31.8% +/- 11.0% vs 21.2% +/- 8.8%; P < .0001), with more than 71% of all veins showing caliber changes of more than 20%. There was 1 side branch every 5.4 +/- 4.3 cm, with a significantly higher incidence between 20 and 32 cm from the malleolus (P < .0001 to distal, P < .0004 to proximal). Generally, women had more side branches than men (0.30 +/- 0.15 cm(-1) vs 0.25 +/- 0.12 cm(-1); P = .0190). Thick-walled veins (565.7 +/- 138.4 mum) had a significantly higher number of large side branches (P < .0001), and thin-walled veins (398.7 +/- 123.2 mum) had significantly more small side branches (P < .0001). Pronounced intimal thickening ("cushions") was found in 28% of vessels (119.8 +/- 28.0 mum vs 40.1 +/- 18.2 mum; P < .0001). CONCLUSION Although the preferential location of side branches may be addressed by the deliberate discarding of infragenicular vein segments, a diameter constriction of 27% on average would eliminate diameter irregularities in 98% of vein grafts.
Collapse
Affiliation(s)
- Paul Human
- Christiaan Barnard Department of Cardiothoracic Surgery, University of Cape Town, Observatory, South Africa
| | | | | | | | | |
Collapse
|