1. Institute of Cardiovascular Diseases,
Radial artery versus saphenous vein as second coronary graft – long-term patency comparison
Grigore Tinica, Raluca Ozana Chistol, Mihail Enache, Diana Anghel, Flavia Corciova
Institute of Cardiovascular Diseases,
Iasi, Romania

2. Background Randomized trials Observational studies Literature
Radial artery (RAG) and saphenous vein (SVG)
Attractive second conduits in coronary artery bypass grafting (CABG) after the left internal mammary artery (LIMA)
Long-term patency of these grafts related to target vessel ?
STS database – 9% of CABG patients received RAG, 4% received both IMAs;
Limited literature data regarding long term patency;
Persistent concerns regarding RAG spasm  long-term patency limited its usage;
Reported SVG patency rates vary considerably, potentially high early failure rate (11- 30% according to literature).
Randomized
trials
Observational
studies
Literature

3. Aims GENERAL AIMS -when to do/when not to do?
SPECIFIC AIMS
-primary end point - the proportion of RAG and SVG patent at 8 years;
-secondary end point - identifying positive and negative prognostic factors influencing the patency of the two graft types.
GENERAL AIMS
-when to do/when not to do?
-who is a candidate for total arterial revascularisation (TAR)?
-what graft to use?
-how to do?
-how to harvest?
-predictions.

4. 120 presented for CTA evaluation of CABG
Methods
120 patients
Retro- prospective
IBCV Iasi, Romania
Location
Study type
Study group
Time interval
Retro-prospective randomized trial
8 years patency evaluation RAG vs SVG by computed tomography angiography (CTA)
1596 operated between at the Institute for Cardiovascular Diseases, Iasi, Romania
322 patients invited to evaluation
120 patients - CTA evaluated
RAG – 55
SVG - 65
322 invitation letters for check-ups submitted to patients operated
120 presented for CTA evaluation of CABG
All CTA results verified by conventional coronarography
Mean follow-up interval:
RAG CABG – 7.87 years
SVG CABG years
Perioperative, follow-up and CTA evaluation data analyzed using univariate and multivariate statistical tests in terms of morbidity, mortality, and long term patency

5. All contacted patients
Results
Clinical characteristics of patients
Parameter
CTA follow-up
All contacted patients
RAG
SVG p
Age at surgery
56.57
60.08
0.016
56.7
59.6
Age at control
63.76
68.05
0.02 -
Sex ratio (M:F)
4.67:1
4.52:1
0.371
6.14:1
7.79:1
Smoking
30.90%
46.15%
0.001
31.14%
46.67%
Arterial hypertension (AHT)
63.63%
66.19%
n.s.
64.07%
66%
Diabetes mellitus
29.09%
23.07%
23.33%
Dyslipidemia
81.81%
70.77%
0.03
72.7%
74.9%
History of myocardial infarction
52.73%
55.38%
53.29%
56.67%
LVEF
53±5%
54±10%
27.32%
30.45%
Renal failure
3.63%
7.69%
0.7%
1.1%
Prior PTCA
14.54%
10.77%
0.043
9.58% 8%
Peripheral arterial disease
9.09%
15.38%
0.01
10.2%
14.5%
NYHA III/IV
36.36%
32.30%
48.5%
26.67%
Familial history
30.9%
30.77%
25.75%
40.67%
Surgical timing and graft strategy

6. All contacted patients
Results
Operative data
Parameter
CTA follow-up
All contacted patients
RAG
SVG p
Urgent surgery
3.63%
4.61%
n.s.
13.7% 4%
ACC time
81.10±30.49 min
105.55±39.56 min
<0.001
83.72±35.21 min
103.16±37.41 min
ECC time
118.10±39.69 min
153.44±60.02 min
121.29±36.65 min
150.36±58.15s min
IABP
1.81%
1.2%
5.5%
Concomitant valve surgery
16.36%
16.92%
19%
18.5%
T/Y anastomoses
52.73%
24.61%
49.7%
25.2%
Sequential anastomoses
29.09%
35.38%
0.014
30.1%
36.3%
Number of sequences
0.64
0.63
0.59
0.65
Endarterectomy
0.02
4.5%
No of grafts
2.99
3.35
3.07
3.29
Harvesting technique
Anastomosis type
Anastomosis location
Flexible operative plan
Intraoperative decision conditions the results

7. All contacted patients
Results
In hospital postoperative data
Parameter
CTA follow-up
All contacted patients
RAG
SVG p
>3 days in ICU
90.91%
93.85%
n.s.
92.7%
93.9%
ICU readmission
3.64%
4.62%
0.045
3.1%
4.5%
Mechanical ventilation >24h
7.69%
0.01
3.3%
7.5%
Infections
1.82%
6.15%
0.022
6.2%
Sepsis
1.81%
1.54%
1.8% 2%
Inotropic support
63.64%
66.15%
50.90%
34.67%
Arrhythmia
38.18%
38.46%
53.29%
30%
MSOF 0%
4.19%
1.33%
Severe neurological impairment
0.6%
0.67%
Acute renal failure
3.5%
3.08%
3.59%
Acute myocardial infarction
0.3%
1.1%
Gastrointestinal complications
No specific complications in case of RAG
In hospital mortality rate for the 1596 patients – 1.38% (22 cases)
No REDO surgery

8. Long term patency according to graft type and grafted artery
Results
Graft patency, stenosis
Long term patency according to graft type and grafted artery

9. Results Long term graft patency
Long term patency according to native vessel initial stenosis
Mean target vessel stenosis
Patent LIMA-LAD
94%
LIMA-LAD string
90%
LIMA-LAD occlusion
70%
Right coronary artery
RAG
SVG
Patent graft
93%
92%
Graft string
90% -
Graft occlusion
85%
Patent Y anastomosis – LIMA-LAD and RIMA-Diag , RAG-RCA
Patent LIMA-LAD and RAG-OM

10. Oblique marginal artery Posterior descending artery
Results
Long term graft patency
Long term patency according to native vessel initial stenosis
Diagonal artery
RIMA
RAG
SVG
Patent graft
83%
92%
85%
Graft string
80%
93% -
Graft occlusion
75%
88%
90%
Oblique marginal artery
RIMA
RAG
SVG
Patent graft
77%
95%
88%
Graft string -
93%
Graft occlusion
75%
Patent SVG-PDA grafts
Posterior descending artery
RAG
SVG
Patent graft
92%
89%
Graft string -
Graft occlusion
79%
Patent RAG-PDA
String – only in arterial grafts (LIMA, RIMA, RAG) due to competitive flow, ultimately leads to graft failure.
SVG – patent or occluded, no string

11. 322 responses (patients/family)
Results
322 responses (patients/family)
155 SVG
34 non-survivors (21.94%)
121 survivors (78.06%)
65 presenting for CTA (41.94%)
167 RAG
22 non-survivors (13.17%)
145 survivors (86.83%)
55 presenting for CTA (32.93%)
Long term mortality
Higher in SVG compared to RAG
Perioperative risk factors
RAG
SVG
Non-survivors
Survivors
Smoking
50%
28.28%
55.88%
30.17%
Familial history
31.82%
24.88%
44.12%
29.31%
Urgent surgery
22.73%
11.72%
5.88%
3.45%
History of myocardial infarction
72.73%
50.34%
100%
57.76%
Inotropic support
51.03%
Sepsis
9.09%
2.07% 0%
2.59%
Acute renal failure
2.76%
2.94%
0.86%
MSOF
18.19%
2.69%
Postoperative arrhythmia
35.29%
28.45%

12. Results Subjective evaluation of health status at 8 years after CABG
Subjective evaluation of health status at 8 years after CABG compared to preoperative state
Patent SVG-PDA

13. Results
Morbidity, mortality
Surgeon’s decision

14. Discussions
RAG better long-term patency no matter the grafted territory;
Diminished long-term SVG patency rate;
Complex anastomoses (sequential, T, Y) – good long-term patency rate;
Total arterial revascularisation - feasible primary strategy in most patients presenting for first time CABG.

15. Discussions Comparative review
Tinica and col Retrospective % % % % % yrs /1596

16. RAG patency by grafted territory
Discussions
Comparative review
RAG patency by grafted territory
Diagonal
81.82% OM
100%
RCA
86.59%
Tinica and col. Long-term RAG patency at 8 years
Tatoulis J, Buxton BF, Fuller JA, et al. Long-term patency of 1108 radial arterial-coronary angiograms over 10 years. Ann Thorac Surg 2009; 88: 23–30 - Mean time to postoperative angiography was 48.3 months
RAPCO 5.5 years
RAG
89%
SVG
87%
RIMA
83%
RAG
89.47%
SVG
77.4%
RIMA
79.66%
Hayward PA, Buxton BF. Mid-term results of the Radial Artery Patency and Clinical Outcomes randomized trial. Ann Cardiothorac Surg 2013;2(4):
Tinica and col. Graft patency at 8 years

17. Discussions
Factors affecting graft patency
Technical factors
Gentle handling of the tissues
Heparinization before clamping
Full thickness bites
Approximation of the endothelium
Avoid tension on the anastomosis
Appropriate anastomosis diameter compared to the vessel size
Size, shape & type of needles & sutures
Graft related factors
Venous or arterial grafts
Patient related factors
Vessel size (less than 1.5 mm)
Vessel quality (thin or friable vessels)
Disease proximal to the anastomosis (in flow)
Disease at the site of the anastomosis
Disease distal to the anastomosis (out flow)
Drug management
Heparin, papaverine, Aspirin, Clopidogrel (plavix), Persantine (dipyridamole), Cardiazem, Verapamil, warfarin, Calcium blockers
The most significant factor in graft patency is flawless surgical technique.

18. Discussions Advantages Associated risks Contra indications
Harvesting possible simultaneously with median sternotomy
Rapid adaptation in length and caliber
Hemodynamic characteristics similar to native coronary arteries (immediate vasomotor activity)
Reduced risk of infection
Associated risks
Ischemic complications
Cosmetic results
Hypoesthesia
Contra
indications
Positive Allen test
Limb trauma
Canulation lesions
Associated pathology: Raynaud, Dupuytren, vasculitis, sclerodermia, carpal tunnel syndrome, rheumatoid arthritis, chronic renal failure.

19. Skeletonized radial artery
Conduit options
How to decide?
Young patients with diffuse disease – TAR
Elderly patients (>80 yrs) – more SVG
Target vessel degree of stenosis
Co-morbidities
Surgeon’s experience
Operative team (simultaneous harvesting)
Number of anastomoses
Type of anastomoses
Redo CABG
Saphenous vein graft
Skeletonized radial artery

20. Predictions Current low level of knowledge about arterial grafts;
CABG - slowly becoming a subspecialty inside cardiac surgery;
TAR usage – will increase due to the certain advantages of arterial conduits;
Better understanding of arterial grafts handling and physiology conditions the long term patency;
Challenging patients should be evaluated with specific expertise and managed by specific surgical and clinical experts;
Learning curve – true with any form of cardiac surgery procedures;
Further studies are warranted.

21. Conclusions RAG implies shorter ACC and ECC times;
RAG usage is associated with lower perioperative and long term mortality compared to conventional CABG (using at least one SVG);
Arterial grafts associated with better long term patency, no matter the grafted territory;
Radial artery proper to be used as second or third arterial conduit in association with both IMA grafts, particularly for patients with high-grade target vessel proximal stenoses (>90% no matter the grafted territory, almost 100% on the right coronary territory);
One arterial graft is good, two are better, three bring additional benefit (free of symptoms) but more are debatable;
The patency rate of SVG proved by our study is higher than the one reported by consulted literature;

22. Conclusions
RAG usage should be carefully evaluated in diabetic obese females (prohibitive risk) and >80 yrs – the benefit of survival is conditioned by the local risk;
On the right territory, in case of total occlusion, RAG is preferred;
CT has assumed an integral role in characterization of graft patency while allowing investigation of alternative postoperative complications;
Due to increased long-term survival advantages over saphenous vein grafts, RAG use should be particularly indicated for younger patients, with >10 yrs life expectancy, with special attempts to achieve TAR in patients with three vessel disease.

23. Institute of Cardiovascular Diseases, Iasi
St. Marina University Hospital, Varna
Institute of Cardiovascular Diseases, Iasi
Assoc. Prof. Plamen Panayotov, MD, PhD
Prof. Grigore Tinica, MD, PhD
Thank you!