OPCAB IS NOT BETTER THAN CONVENTIONAL CABG Harold L. Lazar, M.D. Harold L. Lazar, M.D. Professor of Cardiothoracic Surgery Boston Medical Center and the Boston University School of Medicine Boston, MA
WHEN CABG IS PERFORMED ON CPB, THERE IS THE POSSIBILITY OF: Myocardial Ischemic Injury Strokes and Neurocognitive Deficits Activation of Inflammatory Pathways Pulmonary Insufficiency Renal Failure Coagulopathies
RETROSPECTIVE STUDIES Largely Single Center Lacked Randomization Selection Biases Intention to Treat Principle Not Honored Lacked Proper Equipment Usually Involved One Surgeon Short Term Outcomes Only Reported Small Sample Size
RETROSPECTIVE STUDIES Racz et al. JACC 2004;43:557-564. NY State Registry for CABG: 1997-2000 68,000 Patients OPCAB vs. On-Pump CABG NO DIFFERENCE IN 30 DAY Risk Adjusted Mortality MI Sternal Wound Infections Renal Failure OPCAB Increased Incidence of GI Complications On-Pump CABG Increased Incidence of Stroke; Reoperation for Bleeding; Average 1 Day Longer Postop HOWEVER, After 3 Years, On-Pump CABG: Higher Survival Less Need for Repeat Revascularization
RETROSPECTIVE STUDIES Hannan et al. Circ 207;116:1145-1152 NY State Registry for CABG: 2001-2004 49,830 Patients OPCAB vs. On-Pump CABG 30 DAY OUTCOMES: No Difference in Mortality. However, risk-adjusted rates favored OPCAB 1.63% OPCAB Patients Converted to CABG had a Mortality of 9.73% OPCAB had lower risk-adjusted rates for Stroke and Respiratory Failure 3-YEAR OUTCOMES No Difference in Mortality OPCAB had Higher Incidence of Re-Revascularization which was unrelated to Surgical Experience (High vs. Low Volume)
PROSPECTIVE RANDOMIZED TRIALS ROBY TRIAL RANDOMIZED ON/OFF BYPASS TRIAL Shrayer et al. N Engl J Med 2009;361:1827-1837 Prospective; Randomized Trial 2,203 Patients; 18 VA Centers; 53 Attending Surgeons Inclusion: Urgent/Elective CABG Exclusion: Emergent/Salvage CABG, CABG + Valve, Target Vessel <1.1 mm; Diffuse Disease Primary Short-Term Endpoint: 30-Day Mortality & MACE Primary Long-Term Endpoint: 1-Year Mortality, MI, Need for Repeat Revascularization
PROSPECTIVE RANDOMIZED TRIALS ROBY TRIAL Results STS Risk Scores and Patient Risk Factors were Similar NO DIFFERENCE in Short-Term Mortality or MACE OPCAB patients received Fewer Grafts/Patient After 1 year, OPCAB patients had: Increased Cardiac-Related Deaths Higher MACE Lower Graft Patency No Difference in Neuropysch Testing Between Groups Results Did Not Differ: Resident vs. Attending High vs. Low Volume Surgeon
PROSPECTIVE RANDOMIZED TRIALS ROBY TRIAL Criticisms Women were Excluded No Data Regarding LDL Values; Use of Statins, ASA, Glycemic Control OPCAB Conversion = 12.4%
PROSPECTIVE RANDOMIZED TRIALS SMART TRIAL Ann Thorac Surg 2011;59:1836-1843 Surgical Management of Arterial Revascularization Therapy Puskas et al. Single Center, Single Surgeon, Prospective Randomized Trial 297 Patients with Elective CABG (OPCAB vs. On-Pump CABG) 140 (44%) Long-Term Survivors: 87 Patients (62% of Survivors) Returned for Follow-up Imaging Following 7.5 Years: NO DIFFERENCE IN MORTALITY NO DIFFERENCE IN GRAFT PATENCY RECURRENT ANGINA WAS MORE COMMON IN THE OPCAB PATIENTS
META-ANALYSES NO DIFFERENCE IN SHORT-TERM MORBIDITY OR MORTALITY BETWEEN OPCAB AND ON-PUMP CABG OPCAB PATIENTS HAVE LESS GRAFTS AND A HIGHER INCIDENCE OF INCOMPLETE REVASCULARIZATION OPCAB IS ASSOCIATED WITH DECREASED GRAFT PATENCY AND A HIGHER INCIDENCE OF REPREAT REVASCULARIZATION STUDIES WHICH INITIALLY SHOWED FAVORABLE EARLY OUTCOMES WITH OPCAB FOUND THAT THESE BENEFICIAL EFFECTS WERE NOT APPARENT LONG-TERM IN SOME ANALYSES, LONG-TERM SURVIVAL IS DECREASED IN PATIENTS WITH OPCAB FACTOR CONTRIBUTING TO DECREASED LONG-TERM SURVIVAL FOLLOWING OPCAB: Incomplete Revascularization Decreased Graft patency
OPCAB AND INCOMPLETE REVASCULARIZATION INCOMPLETE REVASCULARIZATION FOLLOWING SURGICAL OR MEDICAL THERAPY RESULTS IN INCREASED MORTALITY, RE- REVASCULARIZATION, RECURRENT MIs, AND REPEAT HOSPITALIZATION Synnegren et al. JTCVS 2008;136:29-36 Effects of Incomplete Surgical Revascularization Over 5 Years in a Non- Randomized Cohort of 9,408 Patients: Incomplete Revascularization was More Common Following OPCAB In Patients with 3-Vessel Disease, Survival was Decreased Following OPCAB Procedures Proponents of OPCAB Argue: Fewer Grafts with OPCAB Because Surgeons are More Likely to Perform OPCAB in Patients with SINGLE and DOUBLE Vessel Disease However, Studies Looking at the Ratio of Grafted vs. Diseased Vessels Continue to Show That OPCAB Patients are Under-Revascularized
CONSEQUENCE OF CONVERSION FROM OPCAB TO ON-PUMP CABG CONVERTING FROM OPCAB TO ON-PUMP CABG ON AN UNPLANNED BASIS INCREASED: Mortality Strokes Renal Failure Pulmonary and GI Complications Hospital Length of Stay Medical Costs Jin et al. Circ 2005;112:I332-I337
OPCAB DOES NOT ELIMINATE THE DETRIMENTAL EFFECTS OF CPB INFLAMMATION NEUROLOGIC AND COGNITIVE CHANGES QUALITY OF LIFE
OPCAB DOES NOT ELIMINATE THE DETRIMENTAL EFFECTS OF CPB INFLAMMATORY RESPONSES AND BIO MARKERS Both OPCAB and On-Pump CABG Activate Inflammatory Responses OPCAB May Decrease Some Components of Complement But DOES NOT Alter the Production of Cytokines or Chemokines Which Modulate Neutrophil and Platelet Activation Myocardial Ischemia Alone, REGARDLESS OF CPB, is a Major Activator of C5b9 Many Clinical Trials Used Cardiotomy Suction, Non-Bonded CPB Circuits, and Increased Heparin Dosages in the Patients Undergoing On-Pump CABG Castellheim A. et al. Ann Thorac Surg 2008;85:2994-3002
OPCAB DOES NOT ELIMINATE THE DETRIMENTAL EFFECTS OF CPB NEUROLOGIC AND COGNITIVE CHANGES The Majority of Trials Show NO BENEFIT In Reducing Strokes With OPCAB OPCAB DOES NOT Eliminate The Need For Aortic Clamping Neurological Injuries Can Occur During Periods of Hypotension and LV Manipulation Single Clamp Technique Has Significantly Reduced The Incidence of Strokes in On-Pump CABG Patients OPCAB FAILS To Prevent The Decline in Cognitive Function Associated With Coronary Surgical Revascularization Advanced Age and Atherosclerosis Are More Important Determinants of Long-Term Cognitive Dysfunction Than The Type of CABG Procedure Performed Nishiyama KE et al. Ann Thorac Surg 2009;87:1839-1845
OPCAB DOES NOT ELIMINATE THE DETRIMENTAL EFFECTS OF CPB QUALITY OF LIFE OPCAB RESULTS IN NO DIFFERENCE IN: Quality of Life Return to Active Physical Activity Mental Health Kapetanakis et al. J Card Surg 2008;23:120-125
IMPACT OF OPCAB ON GENDER Fu et al. Ann Thorac Surg 2009;87:1090-1096 5,359 Patients Undergoing Coronary Revascularization; Mean Follow-up = 5 Years 30-Day Mortality Was Higher Regardless of The Revascularization Technique In Female Patients Females Undergoing OPCAB Less Likely to Have Received Complete Revascularization Less Likely to Be Free From Long-Term MACE Gender Was An Independent Risk Factor For 30-Day Mortality in On-Pump CABG Patients vs. OPCAB. However, There Was No Difference in Late Survival Between Males and Females Regardless of Whether They Received OPCAB vs. On-Pump CABG Puskus et al. Circ 2007;116:I192-I196 Puskus et al. Ann Thorac Surg 2008;86:1139-1146 OPCAB Resulted in a Reduction in 30-Day Mortality in Women However, After a 10-Year Follow-up, There Was NO DIFFERENCE IN SURVIVAL BETWEEN OPCAB VS. ON-PUMP CABG REGARDLESS OF GENDER
OFF-PUMP CABG DOES NOT PRESERVE RENAL FUNCTION BETTER THAN ON-PUMP CABG: A CASE MATCHED STUDY Elmistekawy et al. J Thorac Cardiovasc Surg 2012;143:85-92 5,589 Patients; Single Center; Non-Randomized Propensity Matching OPCAB Patients Had: A Greater Increase in Postop Creatinine; p=0.007 A Greater Decrease in Creatinine Clearance; p=0.007
OPCAB IS NOT SUPERIOR TO ON-PUMP CABG IN PATIENTS AT HIGH-RISK FOR RENAL DYSFUNCTION Shayan et al. J Card Surg 2011;26:591-595 Retrospective; Non-Randomized Trial 43 Renal Transplant Recipients Undergoing Coronary Revascularization: 21 OPCAB vs. 22 On-Pump CABG OPCAB Patients Were Older; More REOPS in On-Pump CABG RESULTS On-Pump CABG Patients Received More Grafts No Difference in 30-Day or 8-Year Survival No Change in Serum Creatinine at 30 Days Rate of Return to Permanent Dialysis Was Similar in Both Groups
OPCAB OFFERS NO ADVANTAGE IN ELDERLY PATIENTS Li et al. JTCS 2008;136:657-664 Non-Randomized Trial of 1,191 Patients > 65 Years OPCAB = 447 vs. On-Pump CABG = 774 OPCAB Patients Had a Higher Rate of Incomplete Revascularization But Lower Rates of Infection and Pulmonary Complications However, at 30 Days, NO DIFFERENCE in Mortality Between Groups At a Mean of 47 Months: OPCAB Patients Had A Higher Incidence of: Stroke MI Readmissions for Angina Re-revascularization Procedures
CONCLUSIONS: OPCAB VS. ON-PUMP CABG THERE IS NO IMPROVEMENT IN SHORT-TERM MORBIDITY OR MORTALITY WITH OPCAB ANY SHORT-TERM BENEFITS WITH OPCAB ARE NO LONGER APPARENT LONG-TERM THERE IS EVIDENCE TO SUGGEST THAT LONG-TERM SURVIVAL MAY BE REDUCED WITH OPCAB OPCAB: Results in Incomplete Revascularization Increases The Need For Re-Revascularization Procedures Decreases Long-Term Freedom From Recurrent Angina and The Need For Hospitalization Is Associated With Decreased Graft Patency
CONCLUSIONS: OPCAB VS. ON-PUMP CABG PROPONENTS OF OPCAB ARGUE: Early Trials Underestimate The Value of OPCAB Inadequate Equipment Stabilizers, Positioning Devices, Intracoronary shunts Inadequate Surgeon Experience HOWEVER: On-Pump CABG and CPB Have Also Improved: Single Cross Clamp Techniques Heparin-Bonded Circuits Miniaturized Pump Circuitry Reduction in ACT Levels During CPB
CONCLUSIONS: OPCAB VS. ON-PUMP CABG PROPONENTS OF OPCAB ARGUE: OPCAB Is Best Performed In High-Volume Centers After 50-75 Cases Have Been Performed HOWEVER: The Volume of CABG Surgery Is Declining CABG Surgery Must Be Performed: Under All Circumstances On All Patients At All Institutions; Regardless of Hospital or Surgeon Cardiac Volume
GOALS OF CABG SURGERY COMPLETE REVASCULARIZATION TECHNICALLY PERFECT ANASTOMOSIS OPTIMAL USE OF CONDUITS MINIMIZE HEMODYNAMIC INSTABILITY ENHANCE LONG-TERM SURVIVAL DECREASE THE NEED FOR RE-REVASCULARIZATION ON-PUMP CABG IS THE BEST METHOD TO ACHIEVE THESE GOALS