Comparison of Saphenous Vein and Internal Thoracic Artery Graft Patency by Coronary System

doi:10.1016/j.athoracsur.2004.07.047

The Annals of Thoracic Surgery

Volume 79, Issue 2, February 2005, Pages 544-551

Presented at the Fortieth Annual Meeting of The Society of Thoracic Surgeons, San Antonio, TX, Jan 26–28, 2004.

https://doi.org/10.1016/j.athoracsur.2004.07.047 Get rights and content

Background

We sought to compare saphenous vein and internal thoracic artery graft patency by coronary system.

Methods

From 1972 to 1999, 50,278 patients underwent primary coronary surgery; subsequently, 4,333 had angiography of 2,121 internal thoracic artery and 8,733 saphenous vein grafts. Longitudinal analysis was used to model graft occlusion and identify risk factors. Using the model, patency was calculated twice for each graft and compared first as if an internal thoracic artery, and second as if a saphenous vein, were used.

Results

Unadjusted 1-, 5-, and 10-year patency was 93%, 88%, and 90% for internal thoracic arteries and 78%, 65%, and 57% for saphenous veins. At 10 years, internal thoracic arteries were more likely than saphenous veins to be patent to left anterior descending in 99.1% of cases, to diagonals in 98.3%, to circumflex in 98.3%, to posterior descending artery in 98.5%, and to right coronary arteries in 82.5%. For right coronary arteries, saphenous vein patency was equivalent to or better than internal thoracic artery patency early after surgery. However, by 10 years, internal thoracic artery patency was better in right coronary arteries with 70% stenosis or greater. At all times after surgery and all levels of clinically important coronary stenosis, internal thoracic artery patency surpassed saphenous vein patency in grafts to the left anterior descending, diagonal, circumflex, and posterior descending arteries.

Conclusions

Internal thoracic arteries demonstrate better patency than saphenous veins except when grafting moderately stenosed right coronary arteries. When bypassing right coronary arteries with less than 70% stenosis, saphenous veins may be a better choice.

Section snippets

Patients

Using the computerized Cardiovascular Information Registry (CVIR) at The Cleveland Clinic Foundation (CCF), patients were identified and included in this study if they had CABG at CCF between 1972 and 1999 and their medical records contained the following: (1) detailed preoperative angiographic data describing location and severity of native coronary arteriosclerosis; (2) results of at least one postoperative angiogram performed before any repeat coronary intervention; and (3) detailed

Overall Graft Patency

Unadjusted overall patency at 1, 5, 10, and 15 years after CABG was 93%, 88%, 90%, and 92% for ITA grafts and 78%, 65%, 57%, and 53% for SVGs, respectively (Fig 2).

Risk Factors For Graft Occlusion

Risk factors for graft occlusion, identified by multivariable longitudinal analysis, were: (1) degree of proximal coronary artery stenosis for ITA grafts; (2) time from CABG to angiography; (3) coronary artery to which grafts were anastomosed; (4) bypass conduit used (ITA or saphenous vein); (5) gender; (6) patient age; (7) date of

Background

Long-term success of coronary revascularization depends on graft patency [13]. Internal thoracic artery grafts, because of their resistance to arteriosclerosis, are believed to have better patency than SVGs. The excellent patency of ITA grafts is believed to be responsible for increased survival and decreased occurrence of angina and need for reoperation when they are used to bypass the LAD 1, 2. A weakness of ITA grafts is that they are more likely to fail when used to bypass coronary arteries

Summary

At all times after operation and at all degrees of proximal coronary artery stenosis, ITA grafts were more likely to be patent than SVGs when used to bypass the LAD, diagonals, LCx, and PDA. Early after CABG, SVGs demonstrated better or equivalent patency when used to bypass RCAs. However, because of SVG arteriosclerosis, by 10 years postoperatively, ITA grafts were more likely than SVGs to be patent to RCAs with 70% or greater stenosis.

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Data on long-term outcomes in patients with diabetes receiving multiarterial grafting (MAG) versus single-artery grafting (SAG) are limited.
The objective of this study is to compare long-term outcomes between MAG and SAG for coronary artery bypass graft (CABG) surgery in patients with diabetes.
Patients with diabetes who underwent isolated CABG surgeries between 2000 to 2016 were identified using the New Jersey mandatory state clinical registry linked with death records and hospital discharge data (last follow-up December 31, 2019). Patients who underwent CABG for single-vessel disease, with only venous conduits, patients with previous heart surgeries, or hemodynamically unstable were excluded. Patients undergoing MAG and SAG were matched by propensity score. Cox proportional hazard models were used to investigate long-term survival and competing risk analysis was used for secondary outcomes.
Of 24,944 patients, 2955 underwent MAG, and 21,989 underwent SAG CABG. Patients receiving MAG were younger, predominantly men, with a lower prevalence of hypertension, peripheral vascular disease, congestive heart failure, chronic lung disease, and renal failure. MAG was associated with lower long-term mortality compared with SAG in 2882 propensity score-matched pairs (hazard ratio [HR], 0.75; 95% CI, 0.68-0.83); lower risks of repeat revascularization (subdistribution HR, 0.86; 95% CI, 0.76-0.97); and composite outcome defined as death from any cause, stroke, postoperative myocardial infarction, and/or repeat revascularization (HR, 0.76; 95% CI, 0.71-0.82). These results were confirmed in subgroup analyses of women, men, age <70 years, and age ≥70 years patients with diabetes. MAG was also associated with lower mortality compared with SAG in patients with diabetes taking insulin in the entire cohort (Video Abstract).
Patients with diabetes benefit from receiving MAG over SAG and demonstrated improved long-term survival, and lower hazards of secondary and composite outcomes. Coordinated efforts are needed to offer MAG to patients with diabetes.
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Original articleCardiovascularComparison of Saphenous Vein and Internal Thoracic Artery Graft Patency by Coronary System

Background

Methods

Results

Conclusions

Section snippets

Patients

Overall Graft Patency

Risk Factors For Graft Occlusion

Background

Summary

J Thorac Cardiovasc Surg

Am J Surg

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

J Surg Res

J Am Coll Cardiol

Original article
Cardiovascular
Comparison of Saphenous Vein and Internal Thoracic Artery Graft Patency by Coronary System