Surgery Grand Rounds Coronary Artery Bypass Grafting versus Coronary Artery Stenting Charles Ted Lord, R1
Coronary Artery Disease Stenosis of epicardial vessels Metabolic & hematologic Statistics 500,000 CAD death annually in US (71% of all heart disease deaths) 7 million CAD deaths worldwide 16 million in US with CAD
Recent Historical Perspective of Invasive Management of CAD Bypass Grafting (430,000 in 2004) Percutaneous (1.3 million in 2004) Angioplasty Atherectomy Bare Metal Stents Drug-eluting Stents
CABG Indications 1. Left main stenosis / left main equivalent - prognostic benefit if LVEF <50% 2. No proven benefit in 1-2V disease without proximal LAD stenosis 3. NSTEMI if LM/LM equiv CAD 4. STEMI if failed PCI * Understanding of accepted clinical and anatomic indications key to interpretation of stent vs CABG data
Relevant Publications Bare Metal Stents 1. ARTS 2005 2. Stent or Surgery 2002 3. ERACI II Drug eluting Stents 1. Briguori 2007 2. Yang 2007 3. ARTS II
Arterial Revascularization Therapies Study (ARTS) Serruys JACC 2005; 46:575-81 Multicenter, randomized trial (600 BMS vs 605 CABG) multivessel disease First to compare BMS vs CABG outcomes (1, 3, 5 year follow-up)
ARTS Results Angina 21.2 15.5 <0.05 Nitrates-SA 6.1 2.4 0.003 Nitrates-LA 19.6 11.6 0.001
ARTS Results - Diabetics Within stenting arm Diabetic mortality 13.4% DM vs 6.8% (p 0.03, RR 1.98) Revascularization : 42% DM vs 27% (p= 0.002) Within CABG arm: no difference in any MACCE if DM
ARTS Conclusions 1. No difference MI / CVA / death but this study was underpowered to detect a difference in this endpoint. 2. Increased revascularization for BMS 3.5x (10% stent CABG) 3. Increased mortality & revascularization in stenting of diabetics, not CABG 4. Significantly improved symptoms in CABG vs stent
Stent or Surgery Trial Lancet 2002; 360: 965-70 988 patients (500 CABG, 488 BMS), RC design for multivessel disease Randomized 5% of those requiring revascularization
SoS Results Stent 5% mortality Significantly less freedom from angina, more antianginal medications 21% revascularization 11% stent x1 2% stent x2 9% CABG CABG 2% mortality 6% revascularization 4% stent x1 1% stent x2 1% CABG
SoS Conclusions 1. 3 yr mortality with stenting 2. revascularization (3.8x); 10% CABG 3. More symptoms, more meds with BMS 4. Immodest Claims: Majority of patients randomized without LM or 3V CAD, all with normal LVEF yet primary purpose to examine development of PCI from single lesion procedures to complex multivessel revascularization
ERACI - II Rodriguez JACC 2001; 37:51-58 Randomized 225 BMS vs 225 CABG (1996-98) for multivessel disease, normal LVEF 16% of eligible enrolled 40% 2V, 55% 3V CAD Included unprotected LM disease (5%) for BMS if amenable according to interventionalist point of view (Class III according to AHA/ACC)
ERACI Results Complete revascularization: 85% CABG vs 50% BMS No revasc: 95% CABG vs 83% BMS (p<0.001) No angina: 92% CABG vs 84% BMS (p=0.001) In-hospital / 30 day Events
Observational Data Hannan NEJM 2005; 352:2174-83 59,314 patients in NY registry of BMS vs CABG, 1997-2000 Data risk-adjusted: CABG group with higher comorbidity, more extensive disease
Results Hannan NEJM 2005; 352:2174-83 Group All (adjusted death HR) Diabetes (adjusted death HR) 2V (no LAD) 0.75 (0.58-0.98) 0.69 (0.46-1.03) 2V (nonprox LAD) 0.76 (0.60-0.96) 0.59 (0.40-0.87) 2V (prox LAD) 0.75 (0.66-0.86) 0.71 (0.57-0.88) 3V (nonprox LAD) 0.74 (0.62-0.90) 0.65 (0.49-0.85) 3V (prox LAD) 0.64 (0.56-0.74) 0.69 (0.55-0.86) Stent CABG Stent 27.3 7.8 CABG 4.6 0.3
Drug-eluting Stents Briguori Am J Cardiol 2007; 99: 779-84 DES (69) vs off-pump CABG (149): diabetics with multivessel CAD Prospective, nonrandomized, 12 mo follow-up No difference in MI, CVA (at 12 mo late thrombosis?) Increased revasc in DES (19% vs 4.7% at 12 mo)
Drug-eluting Stents Yang J Intervent Card 2007; 20:10-16 DES (235) vs CABG (231), prospective nonrandomized, 24 month follow-up Significant baseline disease differences, non-adjusted analysis No difference in MI, CVA, death. 4x increased revasc in DES 10.4 % 2.8% (p=0.001)
Drug-eluting Stents Serruys ARTS II. Eurointervention 2005; 1:147-56 DES (607) vs historical comparison to ARTS I groups (BMS, CABG) Results: 1. Decreased vs BMS but increased revascularization rate vs CABG 2. Increased mortality and revascularization rates in presence of DM with DES
Future Directions FREEDOM Trial Multivessel CAD, diabetes: DES vs CABG Prospective randomization of 2,400 patients, opened 2004 Evaluate 5 year mortality, endpoint of all cause mortality/mi/cva CARDS (VA Coronary Artery Revascularization in Diabetes) Multivessel CAD, diabetes: DES vs CABG Randomized, multicenter, 790 enrollment open 2006-2010 Outcome: time to death or MI
Future Directions CARDIA Coronary Artery Revascularization in Diabetes Multivessel or complex single vessel dz 600 patients, UK multicenter, prospective randomized SYNTAX Synergy Between PCI with Taxus & Cardiac Surgery Multivessel or LM CAD 1800 enrollment, 2005-2012 Outcome: 12 month MACCE
In view of the survival benefit shown for coronary artery bypass grafting, the real controversy is why patients with symptoms and anatomy known to benefit from the procedure are still submitted to percutaneous coronary intervention. -Lancet 2006; 367: 69-78 Because prior clinical trials comparing PCI techniques versus CABG showed that restenosis is the primary drawback, many interventionists consider it reasonable to assume that PCI with DES now ought to be considered equivalent, if not superior, to bypass surgery. -Klein, JACC 2006;47:22-6
Indication Creep for Stents 1 vessel 2 vessel 3 vessel CABG, LVEF Stent CABG Spectrum of CAD
Conclusions Study design Comparison in patients where CABG benefit is less Dilution of true differences by heterogeneity of multivessel disease Relevance? Small studies, none enrolling > 15% Equivalent revascularization at randomization Studies look only at initial treatment. No survival difference due to high re-pci/cabg crossover? Less symptomatic relief with stents Mortality increase in stenting diabetics No evidence that PCI safe or effective in LM CAD Future studies are similarly flawed to perpetuate BMS data errors into DES era Patients want less invasive treatment is a judgement