The Challenging Dream of Rene Favaloro and Genesis of Saphenous Venous Grafts

During the past decade, aorto-coronary bypass surgery (ACBS) has been widely prescribed as treatment of angina pectoris. Dysfunction or closure of an aortocoronary bypass graft (ACBG) is generally suggested by a number of vague subjective complaints and few, if any, objective signs derived by history, physical examination, resting and stress E.K.G., and lately by Thallium201 regional myocardial perfusion studies. Definitive confirmation of graft closure or stenosis has traditionally required post operative selective catheterization and angiography of the grafts in question. We have utilized CAT to determine patency of an ACBG with encouraging results. Biological motion has been the principle deterrent to the use of CAT in evaluating the coronary arteries and cardiac chambers. Third and fourth generation scanners have been employed to explore the feasibility and potential use of CAT in imaging cardiac structures. Surprisingly, excellent quality images are currently being obtained with exposure times of one to five seconds, even though some of these images are reconstructed from repetitive data obtained during one or more cardiac cycles partially degrading the image. CAT demonstration of the cross-sectional anatomy combined with simultaneous contrast media enhancement represents the basic ingredients utilized to demonstrate the patency of ACBG. Sixty-five patients have undergone this procedure after single or multiple revascularization procedures. Eighteen of these patients, with a total of thirty-three grafts, had correlative selective angiography of the individual venous grafts. Twenty-two grafts proved to be patent with both techniques while ten of eleven thrombosed grafts were properly predicted by CAT. The benefits of this relatively non-invasice, safe, repeatable, and accurate method for detectinq ACBG is presented.

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SP611INFECTIONS IN TERTIAIRY VASCULAR ACCESS; A COMPARISION BETWEEN BRACHIO-BASILIC ARTERIOVENOUS FISTUALE AND ARTERIO-VENOUS GRAFTS

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfv198.34 ◽

2015 ◽

Vol 30 (suppl_3) ◽

pp. iii579-iii579

Author(s):

Safia Zafarullah ◽

Teun Wilmink ◽

Sarah Powers ◽

Jyoti B Bharani

Keyword(s):

Vascular Access ◽

Venous Grafts

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Effect Of TicloPidine On Platelet Deposition In Gore-Tex And Autologous Vein Grafts

10.1055/s-0038-1652494 ◽

1981 ◽

Cited By ~ 1

Author(s):

K P Murphy ◽

M K Dewanjee ◽

V Fuster ◽

P Didisheim ◽

M P Kaye

Keyword(s):

Inhibitory Effect ◽

Unit Weight ◽

Internal Reference ◽

Autologous Vein ◽

Venous Grafts ◽

Fold Reduction ◽

Platelet Aggregometry ◽

Autologous Vein Graft ◽

Platelet Deposition

To quantitatively study platelet deposition on arterial prostheses and the effect of platelet inhibitory therapy with ticlopidine, 14 dogs underwent bilateral femoral artery excision and replacement with one polytetrafluoroethylene (Gore-Tex) and one autologous vein graft. Five dogs received 60 mg/kg/day of ticlopidine orally on four consecutive days prior to surgery. Nine untreated dogs served as controls. Collagen-induced platelet aggregometry studies were performed at the end of day 4. Autologous indium-111-labeled platelets were injected 24 hours prior to surgery to serve as aplatelet marker. All animals received heparin (1 mg/kg I.V.) 5 minutes prior to excision of the arterial segment. Grafts were removed 1 hour following resumption of blood flow and gently flushed with 30 cc normal saline. Radioactivity per unit weight of Gore-Tex, vein and blood was determined with a gamma counter. The relative radioactivity with respect to the internal reference standard, blood, is tabulated below.Ticlopidine treated dogs showed a 15-fold reduction in platelet deposition on Gore-Tex grafts and a 3-fold reduction on venous grafts. Platelet deposition was reduced significantly in Gore-Tex grafts (P<0.001) to a level comparable to that in autologous veins. Platelet inhibitory effect was also observed in collagen-induced platelet aggregometry.According to this “in vivo” data, ticlopidine appears to be a promising platelet inhibiting agent.

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Prostacyclin Production By Autogenous Venous Grafts In Dogs

10.1055/s-0038-1652508 ◽

1981 ◽

Author(s):

A Eldor ◽

E L Hoover ◽

S B Pett ◽

W A Gay ◽

D R Alonzo ◽

...

Keyword(s):

Carotid Artery ◽

Defense Mechanisms ◽

Jugular Vein ◽

Jugular Veins ◽

Vein Grafts ◽

Venous Grafts ◽

System A ◽

Radioimmune Assay ◽

Smooth Muscle Proliferation ◽

Prostacyclin Production

Arteries are capable of producing significantly larger quantities of prostacyclin than veins. Experiments were designed to compare the production of prostacyclin by venous autografts to that of normal veins and arteries, and to test the hypothesis that prostacyclin production by the vessel wall is related to blood pressure and flow. In 20 dogs a segment of jugular vein was interposed into the carotid system; a sham dissection was done on the opposite side. Six weeks later specimens of venous autograft, jugular vein and carotid artery were taken for histology and radioimmune assay of prostacyclin. “Arterialized” vein grafts showed prominent intima lined by endothelium, medial smooth muscle proliferation and fibrotic proliferation in adventitia. Spontaneous and arachidonic acid stimulated prostacyclin production was not significantly different in venous autografts and jugular veins. Significantly larger amounts of prostacyclin were synthesized by the carotid artery; table shows mean ± S.E. in ng/ml.We conclude that the histological and rheological changes in vein grafts do not affect prostacyclin production. While normal veins never develop atheroma, atherosclerosis is prevalent in venous autografts. The above may be explained in part by the impairment of one of the vascular defense mechanisms, namely the decreased prostacyclin production in venous grafts.

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Intraoperative flow profiles of arterial and venous bypass grafts to the left coronary territory

European Journal of Cardio-Thoracic Surgery ◽

10.1093/ejcts/ezy473 ◽

2019 ◽

Vol 56 (1) ◽

pp. 64-71 ◽

Cited By ~ 3

Author(s):

Sanaz Amin ◽

Per Lav Madsen ◽

Raphael S Werner ◽

George Krasopoulos ◽

David P Taggart

Keyword(s):

Transit Time ◽

Pulsatility Index ◽

Artery Bypass ◽

Diastolic Filling ◽

Arterial Grafts ◽

Venous Grafts ◽

Flow Profiles ◽

Significant Difference ◽

Coronary Territory ◽

Transit Time Flowmetry

Abstract OBJECTIVES The different mechanical and vasodilatory properties of arteries and veins may influence their flow profiles when used for coronary artery bypass grafting (CABG). This may be of significance when assessing the cut-off values for adequate flow. However, conduit-related flow differences are less examined. METHODS In a study of 268 patients, transit time flowmetry parameters of 336 arterial and 170 venous conduits all grafted to the left coronary territory were compared. With transit time flowmetry, the mean graft flow (MGF), pulsatility index, percentage of diastolic filling and percentage of backwards flow were measured. Conduit-related differences were further compared according to on- or off-pump CABG (ONCABG versus OPCABG) surgery. RESULTS Overall MGF and pulsatility index were comparable between arterial and venous grafts, but in arterial grafts, MGF was higher during ONCABG than during OPCABG (49.1 ± 35.3 ml/min vs 38.8 ± 26.6 ml/min; P = 0.003). Percentage of diastolic filling was higher in arterial grafts than in venous grafts (overall 71.0 ± 7.9% vs 63.7 ± 11.1%; ONCABG 69.9 ± 7.1% vs 63.9 ± 10.4%; OPCABG 71.9 ± 8.3% vs 63.4 ± 12.2%; all P < 0.001). Furthermore, percentage of backwards flow was higher in arterial grafts than in venous grafts in the overall (2.3 ± 3.2% vs 1.7 ± 3.2%, P = 0.002) and in the ONCABG (2.3 ± 3.2% vs 1.3 ± 2.5%, P < 0.001) cohorts. In venous grafts, percentage of backwards flow was lower during ONCABG versus OPCABG (1.3 ± 2.5% vs 2.6 ± 3.9%, P = 0.016). CONCLUSIONS No statistically significant difference was observed for MGF and pulsatility index between arterial and venous conduits. However, arterial grafts have significantly higher diastolic filling and backwards flow than venous grafts. Furthermore, arterial grafts have a significantly higher MGF in ONCABG versus OPCABG.

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