Total Arterial Revascularization Where is the evidence?
Yousry El Moazamy Consultant cardiac surgery PSCC Qassim
Background ďƒ˜ The
effectiveness of CABG in relieving symptoms and prolonging life is directly related to graft patency.
ďƒ˜
Because arterial and venous grafts have different patency rates and modes of failure, conduit selection is important in determining the long-term efficacy of CABG.
Saphenous vein grafts
5 years 20% partial or total obstructions,
10
years 50% totally obstructed or showed some angiographic evidence of pathologic changes .
Dr. Bruce Lytle and Dr. Gosta Pettersson Cleveland Clinic Heart and Vascular Institute Copyright © 2013
LIMA, RIMA and SVG patency rate %
100 90 80 70
lima rima svg
60 50 40 30 20 <1 year
A. Califori 2004
1-5 years
>5 years
Arterial conduits for CABG LIMA RIMA Radial
Gastroepiploic
rarely used.
and inferior epigastric are
Internal Mammary Arteries
Better patency (10-year patency _90%) Improved survival benefit is independent of the patient’s sex, age, extent of CAD, and LV function. Reduces the incidence of late MI, hospitalization for cardiac events, need for reoperation, recurrence of angina.
The disadvantage: It may spasm and eventually atrophy if used to bypass a coronary artery without a flow-limiting stenosis.
Contraindication : Emergency surgery, poor LIMA blood flow, subclavian artery stenosis, radiation injury, atherosclerosis.
Dr. Bruce Lytle and Dr. Gosta Pettersson Cleveland Clinic Heart and Vascular Institute Copyright © 2013
BIMA ď&#x192;&#x2DC; Numerous
observational studies have demonstrated improved morbidity and mortality rates when both IMAs are used.
ď&#x192;&#x2DC; It
appears to be associated with an increased incidence of sternal wound infections in patients with DM and those who are obese .
ART Trial
Radial Artery
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The radial artery is a muscular artery that is susceptible to spasm and atrophy when used to graft a coronary artery that is not severely narrowed.
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Radial artery graft patency is best when used to graft a LCX with >70% stenosis and worst when it is used to bypass RCA with a stenosis of only moderate severity.
Radial Artery and Saphenous Vein Patency More Than 5 Years After Coronary Artery Bypass SurgeryResults From RAPS (Radial Artery Patency Study)
Background
In the RAPS study, complete graft occlusion was less frequent in radial artery compared with SVG 1 year postoperatively while functional occlusion was similar. Saswata Deb et al, J Am Coll Cardiol. 2012;60(1):28-35.
Methods: A total of 510 patients <80 years of age undergoing CABG with 3-vessel disease in 9 Canadian centers.
Target vessels for the RA and study SVG were RCA, CX coronary arteries, which had >70% proximal stenosis.
Within-patient randomization was performed; RA was randomized to either the right or circumflex territory and the study SVG was used for the other territory.
The primary endpoint was functional graft occlusion by invasive angiography at least 5 years following surgery. Complete graft occlusion by invasive angiography or CT angiography was a secondary endpoint.
RAPS trial
Results : The frequency of functional graft occlusion RA Group 12.0% . SV Group 19.7% ( p = 0.03) The frequency of complete graft occlusion RA Group 8.9% SV Group 18.6% ( p = 0.002)
Conclusions: Radial arteries are associated with reduced rates of functional and complete graft occlusion compared with SVGs more than 5 years following surgery.
Saswata Deb et al, J Am Coll Cardiol. 2012;60(1):28-35.
The gastroepiploic artery
Most often used to bypass the RCA or its branches. It is prone to spasm and therefore should only be used to bypass coronary arteries that are severely stenotic. The 1-, 5-, and 10-year patency rates of the gastroepiploic artery are reportedly 91%, 80%, and 62%, respectively.
The inferior epigastric artery
It is only 8 to 10 centimeters in length and therefore is usually used as a “Y” or “T” graft connected to another arterial conduit.
On occasion it is used as a free graft from the aorta to a high diagonal branch of the LAD .
It is prone to spasm and therefore is best used to bypass a severely stenotic coronary artery.
Its reported 1-year patency is about 90%.
Impact of arterial revascularization in patients undergoing coronary bypass
Nasso G,et al 2012. Anthea Hospital, GVM Care & Research, Bari, Italy
Retrospectively
reviewed 10,752 patients . Average follow-up was 37.2 months. Three groups (3584 patients each) : G I: One IMA plus SV grafts G II: BIMA plus SV grafts G III: Total arterial revascularization.
J Card Surg. 2012 Jul;27(4):427-33
RESULTS:
Overall operative mortality was 2.8%.
Mortality was not statistically different among groups,
Group II and III displayed in the long-term better freedom from cardiac death and from adverse cardiac events (repeat revascularization, myocardial infarction, recurrent angina).
Use of only one arterial conduit, diabetes and depressed LVEF predicted cardiac mortality,
CONCLUSIONS: These data strongly support the practice of using two arterial conduits rather than one. The operative and late results of coronary surgery with arterial conduits are optimal and should serve as a current benchmark for the comparison with state-of-the-art percutaneous interventions.
J Card Surg. 2012 Jul;27(4):427-33
Mid-term Outcomes of Total Arterial Revascularization Versus Conventional Coronary Surgery in Isolated ThreeVessel Coronary disease
Between 2003 and 2005, 503 patients. 117 patients (Artery group) 386 patients (Vein group). Mean follow-up was 6.1 ± 0.9 yr. After adjustment for differences in baseline risk factors, risks of death (hazard ratio [HR] 0.96; 95% confidence interval [CI] 0.51-1.82, P = 0.90), myocardial infarction (HR 0.20, 95% CI 0.02-2.63, P = 0.22), stroke (HR 1.29, 95% CI 0.35-4.72, P = 0.70), repeat revascularization (HR 0.64, 95% CI 0.26-1.55, P = 0.32) and the composite outcomes (HR 0.83, 95% CI 0.50-1.36, P = 0.45) were similar between two groups. Jin Woo Chung,1 et al 2012 Konkuk University School of Medicine, Seoul, Korea.J
Since the use of veins does not increase the risks of adverse outcomes compared with total arterial revascularization, a selection of the conduit should be more liberal. Jin Woo Chung,1 et al 2012 Konkuk University School of Medicine, Seoul, Korea.J Korean Med Sci. 2012
ÂŤ Exclusive Âť Mammary Artery Grafting for complete myocardial revascularization How to perform more IMA grafting ? Or How to avoid other grafts ?
Exclusive IMA grafting ď&#x192;&#x2DC; One
mammary artery is better than other grafts ď&#x192;&#x2DC; Two mammary arteries are better than one
(Lytle)
Expanding mammary artery « use » Ways to do it… Skeletonized
harvesting of the IMAs
Segmentation
Y
of the LIMA
grafting of both IMAs & sequential anastomoses.
Patrick NATAF,CCN ,2004
Segmentation of the LIMA
Skeletonization gives an excess of length
This excess of length provides an additional graft (end – side anastomosis). LIMA
(Heart Surgery Forum, 2003, 6: 520-1)
RIMA
IVA
CX
CT angiography
One stepâ&#x20AC;Ś(branch) further Double Y Graft
Patrick NATAF,CCN , 2004
Y grafting of both IMAs sequential anastomoses
Freedom from death = 86%
Freedom from reintervention = 94%
Y grafting of both IMAs & sequential anastomoses
Conclusion
There is strong evidence that one mammary artery is better than no mammary artery and two mammary arteries are better than one .
Recent studies demonstrated that total arterial revascularization can give better results in term of patency and event free survival.
“Exclusive” internal mammary grafts can achieve complete myocardial revascularization in most of the cases.
Conclusion Diabetic patients have not to be denied BIMA grafting or total arterial revascularization, as there is a better outcome if compared with a conventional CABG . Use of off-pump surgery does not reduce the quality of the results of total arterial revascularization.
Thank You