Radial Artery Grafting: Why Do It? (Evidence Basis)

Transcription

1 Advanced Techniques for State of the Art CABG Session AATS 2015 Radial Artery Grafting: Why Do It? (Evidence Basis) David P Taggart MD PhD FRCS FESC Professor of Cardiovascular Surgery, University of Oxford Conflicts of Interest:None

2 RA at 20 years

3 Radial Artery Grafting: Why Do It? (Evidence Basis) Easy to harvest Long length Better wound healing PRONE TO SPASM 4 Questions 1 Patency vs SVG? 2 Patency vs RIMA? 3 Clinical Outcomes? 4 Spasm Prophylaxis

4 Patency rates Harvest: open vs closed Skeletonized vs non-skeletonized Anastomoses: single vs sequential Proximal End: aorta vs composite to IMA

5 [ATS 2004] (15%) 5 3 2

6 JAMA 2011 SVG numbers week angiography patency 97% 99% 1 year angiography patency 89% 89% (LIMA to LAD patency) 97% 94% Also reported Only use if minimum of 70% stenosis in native coronary artery SVG patency poorer with EVH (78% vs 91%; p=0.009) SVG patency poorer with Off pump (78% vs 90%; p=0.04) Same RA patency with calcium channel blockers (93% vs 87%;p=0.09) More disease in radial arteries of diabetic patients RA

7 JACC 2012 OCCLUDED FUNCTIONAL OCCLUSION RA SVG p RA SVG p 1 yr 8.2% 13.6% % 13.7% ns 8 yrs 8.9% 18.6% % 19.7% 0.03 At 1 year no difference in functional patency of RA and SVG but marked superiority of RA at 8 years in patency and functional patency

8 JTCVS 2010 o5 RCTs including 936 patients o71% repeat angiography at mean of 22 months (range months) ofailure rate 14.1% RA and 14.6% SVG EJCTS 2011 Time Grafts HR SVG failure vs RA < 1yr (95% CI: ) 1-5 years (95% CI: ) > 5 years (95% CI: )

9 [EJCTS 2012] 7 YEARS number % patent p LIMA % RA % RIMA 58 88% 0.32 Free IMA 55 80% 0.6 SVG

10 Effect of severity of target % stenosis on patency Study Joung (2004) Patients Follow-up (years) >70% <70% Δ % 64% -36% Desai (2007) % 85% -8% Maniar (2002) % 57% -23% Yie (2008) % 79% -15% Gaudino (2004) % 67% -27% Patency significantly lower if <70% stenosis

11 Effect of site of proximal anastomosis on patency Study Patient Follow-up (year) Aortocoronary Composite Jung (2009) 893 early 98% 95% -3% 1 94% 91% -3% 2 91% 85% -6% Δ Maniar (2003) Lemma (2004) Carneiro (2009) Gaudino (2004) 5 74% 65% -9% % 70% -5% % 86% -4% % 81% -3% % 84% -6% superior patency with aorto-coronary vs composite grafting

12 [JTCVS 2003]

13 [JACC 2007]

14 JAHA 2013

15 [ATS2014] years

16 RCT: RA vs RIMA [JTCVS 2010] < 70 years > 70 years BUT: All RIMA anastomosed to aorta = inferior patency

17 [CIRC 2011]

18 [EJCTS 2015] RA BIMA p Death 0.6% 1.7% 0.08 CVA SWI different hospitals One using RIMA one using RA IMA harvested as pedicles IMA: aortic anastomosis

19 [ATS 2014]

20 7. 7 YEARS [JTCVS 2014]

21 RA Jump Graft from LAD to PDA [Asian Cardiovasc Thorac Ann 2009] oadvantages vs Composite Grafts Distal LAD usually disease free (receives NO from RIMA/LIMA?) Avoids technical problem of RA/IMA anastomosis-size discrepancy Avoids problem of steal syndrome with composite grafts Technically easy

22 Radial Artery Strong angiographic evidence of superior patency of RA over SVG beyond one year (but inferior to RIMA) Superior patency of RA when coronary stenoses >70% and RA contraindicated in large coronary with moderate stenosis (needs SVG or stent) Superior patency of RA when aorto-coronary rather than composite graft Conflicting evidence in the literature in comparing the clinical superiority of RITA vs RA as 2 nd arterial conduit Strong indication for RA when BIMA contraindicated: despite less favourable endothelial function in patients with diabetes RA still has superior late patency to SVG

23

24 [EJCTS 2015]

25 Overview Historical perspective and trends Pathological features Comparison of patency to LSV Surgical factors affecting patency Severity and location of target stenosis Harvesting technique Aorto-coronary vs. composite grafting Sequential grafting Patient selection Pharmacological management

26 Historical perspective and trends First described by Carpentier et al in 1973 Further results in 1975 discouraged use Higher rate of occlusion/narrowing (35%) than LSV Revival with updated Carpentier data in 1992 Patent grafts at up to 18 years follow-up Further series (100% early patency for 56 RAs) SCTS: 15% CABG involve two arterial

27 Pathological features RA LS V IMA

28 RCTs RCT <1 year <5 years >5 years Desai (2004) RAPS Collins (2008) RSVP Hayward (2010) RAPCO Goldman (2011) Occlusion: RA 8.2%, LSV 13.6% (p=0.009) String sign: RA 7.0%, LSV 0.9% (p=0.001) Patency: RA 89.0%, LSV 89.0% (p=0.98) Patency: RA 98.3%, LSV 86.4% (p=0.04) (Debs 2012) Functional occlusion: RA 12.0%, LSV 19.7% (p=0.03) Complete occlusion: RA 8.9%, LSV 18.6% (p=0.002) Patency: RA 90.0%, LSV 87.0% (p=0.29)

29 Meta-analyses Study <1 year <5 years >5 years Benedetto (2010) Hu (2011) Athanasiou (2011) Patency: RA vs. LSV: OR 1.04 (95% CI , p=0.84) Failure: RA 14.1%, LSV 14.6% (p=0.372) Occlusion: RA vs. LSV: RR (95% CI , p<0.05) Patency: RA vs. LSV: OR 2.06 (95% CI , p=0.002) Patency: RA vs. LSV: OR 2.28 (95% CI , p=0.003) Cao (2012) Complete occlusion: RA 9.1%, LSV 12.7% (OR 0.71, p=0.15) String sign: RA 7.4%, LSV 1.0%(OR 7.97, p< ) Failure: RA 18.4%, LSV 15.5%(OR 1.26, p=0.34) Complete patency: RA 79.2%, LSV 82.5%(OR 0.79, p=0.33) Complete occlusion: RA 2.7%, LSV 14.7% (OR 0.17, p=0.002) String sign: RA 2.7%, LSV 0% (OR 3.55, p=0.17) Failure: RA 6.0%, LSV 17.5%(OR 0.31, p=0.004) Complete patency: RA 89.9%, LSV 63.1% (OR 5.19, p<0.0001)

30 Surgical factors affecting patency

31 Effect of location of target stenosis on patency RCA as a target may predict stenosis due to relatively large cross-sectional area and resultant effect on competitive flow Although, RAPCO RA-RCA 87% patency (mean follow-up 6 years)

32 Effect of harvesting technique on patency Study Bleiziffer (2007) Ito (2009) Dimitrova (2010) Amano (2002) Miyagi (2006) Patients Followup(months) Harvesting technique Endoscopic Open % 79% % 94% (endoscopic) 78.3 (open) 84% 79% Skeletonized Pedicled 243 <3 97% 85% 131 ~0.5 98% 87% ~9 (skeletonized) ~12 (pedicled) 100% 78% Comparable patency rates for endoscopic and open RA harvesting. Skeletonisation may improve patency

33 Effect of sequential vs. single grafting on patency Study Patients Sequential grafts Technique Single grafts Silva (2009) % 71% Oz (2006) % 67% Nakajima (2012) % 97% Sequential in poor distal run-off Single in poor distal run-off Oz (2006) % 49% Akinci (2005) 51 Followup(months) 13(aortocoronary) 9(composite) Sequential with aorto-coronary Sequential with composite 97% 45% Patency may improve with sequential grafting, including with poor distal run-off, and may improve further when combined with aorto-coronary grafting

34 Patient selection Contraindications Dupuytren s contracture Carpal tunnel syndrome AV fistula Assessment Allen s test Modified Allen s test Asif & Sarkar: 100% sensitivity in >600 patients Duplex ultrasound Abu-Omar et al: enables use of 99% of RA in patients with positive Allen s

35 Patient selection Predictors of graft failure One year Desai et al (RAPS): PVD strongest predictor of occlusion Two to three years Bartnes et al: diabetes, female gender Late Hata et al Univariate: female gender, smoking history, PVD, lack of statin, use of only one anti-platelet agent Multivariate: PVD

36 Pharmacological management Papaverine Agent Phenoxybenzamine Verapamil with nitroglycerin Vasoconstrictors inhibited Epinephrine Phenylephrine Potassium Norepinephrine Dopamine Epinephrine Phenylephrine Potassium Norepinephrine Angiotensin II Epinephrine Phenylephrine Potassium Prostglandin F(2 aplha) Duration of action Impair endothelial function? 30 minutes to 2 hours Yes > 18 hours No 5 to 24 hours No

37 Summary RA patency comparable to LSV patency in short-term but superior over medium- and long-terms Avoid <70-80% stenosis in target coronary arteries Endoscopic harvesting: reduced morbidity, improved patient satisfaction, comparable patency to open harvesting Skeletonization may improve short-term patency, although more data required to establish clear differences at short- to long-term follow-up Both aorto-coronary and composite configurations safe, although sequential anastomoses may improve patency compared to single anastomosis Consider risk factors for graft occlusion, particularly PVD and employ duplex ultrasound in patient selection Topical vasodilators minimise early graft failure. Pheoxybenzamine with verapamil and/or nitroglycerin more effective than papaverine.

38 Summary and Conclusions o STRONG ANGIOGRAPHIC EVIDENCE OF SUPERIOR PATENCY OF both IMA vs SVG RA vs SVG IMA vs RA (in studies out to 20 years) o CLINICAL EVIDENCE Strong evidence of improved survival with BIMA vs SVG Strong evidence of improved survival with RA vs SVG One small RCT of RA vs RIMA (but RIMA anastomosed to aorta) One small PPM reported superior survival and MACCE with RIMA vs RA One PPM reported superior survival and MACCE with RA vs RIMA (but with RIMA anastomosed to aorta as a free graft) o Best evidence still supports RIMA as 2 nd best arterial graft o For BIMA avoid obese diabetes and skeletonize o But RA a good alternative when contraindications to RIMA

39 RIMA or RA as the Second Arterial Graft? o No large randomized trials o Angiographic evidence of patency of BIMA patency of RA (vs SVG) o Clinical evidence for survival benefit of BIMA RA o Comparison of clinical outcomes of RIMA vs RA o When may RA possibly be preferable to RIMA?

40 66% 79%

41 ALL 2780 patients 1620 angiograms Mean 7.7 years FU RIMA (145) RA (871) RGEA (92) SVG (845): HR x3 Failure > 4 years