BACKGROUND
• ONCAB IS NOW PERFORMED WITH
LOW MORTALITY AND MORBIDITY:
• 30-DAY MORTALITY: 1-2%, CVA/MI/AKI-F: 2-5%
• OPCAB INITIALLY DEVELOPED TO AVOID THE PERIOPERATIVE COMPLICATIONS OF CPB AND TO
REDUCE COST (ESP IN DEVELOPING NATIONS)
• UPTAKE
OF
OPCAB HAS PLATEAUED TO 10-20% OF ALL CABGS IN UK AND USA
• IMPROVED OUTCOMES WITH ONCAB
• TECHNICAL DIFFICULTY OF OPCAB
• RECENT EVIDENCE SUGGESTING WORSE
MID-TERM OUTCOMES WITH OPCAB
• OVER 50 RCTS COMPARING OPCAB AND ONCAB.
• THE 4 LARGEST, MULTICENTRE
RCTS:
• CORONARY (4752 PTS)(30-DAY AND 1-YEAR OUTCOMES)
• ROOBY (2203 PTS)
• DOORS (900 PTS)
• GOPCABE (2539 PTS)
(ROOBY TRIAL)
BACKGROUND: CORONARY RCT
• LARGEST RCT PERFORMED
• INTERNATIONAL, MULTICENTRE RCT (79 CENTRES, 19 COUNTRIES)
• 4752 PATIENTS ENROLLED
• INCLUSION CRITERIA: HIGH RISK PATIENTS: AGE >70 YEARS, PVD, CVA,
RENAL DYSFUNCTION OR AGE 60-69 + (DM, URGENT, LVEF<35%,
SMOKER).
• EXPERTISE BASED RANDOMISATION: DEFINED AS >2 YEARS OF EXPERIENCE + >
100 PROCEDURES. TRAINEES NOT ALLOWED TO PARTICIPATE.
• PRIMARY OUTCOME: COMPOSITE OF DEATH, NONFATAL CVA, NONFATAL
MI, AKI-RRT, REPEAT REVASCULARISATION
CORONARY: 1-YEAR OUTCOME
Lamy A. et al. NEJM 2013; 368:1179-88.
OBJECTIVE
• TO EVALUATE LONG-TERM OUTCOMES AT 5-YEARS IN
PATIENTS RANDOMISED TO OPCAB AND ONCAB
• HYPOTHESIS:
• OPCAB WOULD BE ASSOCIATED WITH FEWER MAJOR CLINICAL EVENTS IN
THE SHORT TERM (30 DAYS) THAN ONCAB AND THAT THE BENEFITS OF
OPCAB WOULD BE MAINTAINED IN THE LONG-TERM
METHODOLOGY
METHODS: TRIAL DESIGN
• INTERNATIONAL, MULTICENTRE, SINGLE-BLIND RCT (79 CENTRES, 19 COUNTRIES)
• 4752 PATIENTS ENROLLED BETWEEN 2006 AND 2011.
• INCLUSION CRITERIA: ISOLATED CABG WITH MEDIAN STERNOTOMY + HIGH RISK PATIENTS:
AGE >70 YEARS, PVD, CVA, RENAL DYSFUNCTION OR AGE 60-69 + (DM, URGENT,
LVEF<35%, SMOKER).
• EXPERTISE BASED RANDOMISATION: DEFINED AS >2 YEARS OF EXPERIENCE (AFTER
RESIDENCY) + > 100 PROCEDURES. TRAINEES NOT ALLOWED TO PARTICIPATE.
• FOLLOW-UP:
• BLINDED STUDY
PERSONNEL WOULD CONTACT PATIENT YEARLY
• IF EVENT REPORTED, SOURCE
DOCUMENTS WOULD BE OBTAINED TO CONFIRM
• ALL REPORTED COMPONENTS
COMMITTEE
OF THE PRIMARY OUTCOMES WERE REVIEWED BY A BLINDED ADJUDICATION
OUTCOMES AND STATISTICAL ANALYSES
• 2ND CO-PRIMARY OUTCOME: COMPOSITE OF DEATH, CVA, MI, AKI-D OR
REPEAT REVASC AT 5 YEARS
• QUALITY OF LIFE
• ECONOMIC ANALYSIS
• STATISTICAL ANALYSIS
• INTENTION-TO-TREAT
• TIME TO EVENT
PRINCIPLE
ANALYSIS WITH COX REGRESSION (TIME TO FIRST OCCURRENCE OF ANY
COMPONENT OF THE PRIMARY OUTCOME)
• COMPARISONS BETWEEN
GROUPS PERFORMED USING THE LOG-RANK TEST
RESULTS
RESULTS: 2ND CO-PRIMARY OUTCOME
• 4752 PATIENTS ENROLLED. FOLLOW-UP DATA AVAILABLE FOR
98.8% OF PATIENTS
• MEAN FOLLOW-UP OF 4.8 YEARS AFTER RANDOMISATION.
• CO-PRIMARY OUTCOME: OPCAB (23.1%) AND ONCAB
(23.6%)
• HR: 0.98 (95% CI 0.87 – 1.10), P=0.72
COMPLETENESS OF REVASCULARISATION
AUTHOR’S CONCLUSION
• RATE OF THE COMPOSITE PRIMARY OUTCOME (DEATH, STROKE, MI, AKI OR
REPEAT REVASC) AT 5 YEARS OF FOLLOW-UP WAS SIMILAR BETWEEN OPCAB
AND ONCAB
• THERE WAS ALSO NO DIFFERENCE IN COST OR QUALITY
OF LIFE BETWEEN THE
TWO TECHNIQUES
• ALTHOUGH THE MEAN NUMBER OF GRAFTS WAS LOWER IN THE OPCAB
GROUP, THIS DID NOT HAVE ANY EFFECT ON OUTCOMES
• BOTH OPCAB AND ONCAB ARE EQUALLY EFFECTIVE AND SAFE.
DISCUSSION
STRENGTHS OF THE STUDY
• LARGE, MULTICENTRE RCT WHICH WAS POWERED FOR DETECTING
HARD CLINICAL END-POINTS AT BOTH SHORT AND LONG-TERM
FOLLOW-UP
• EXPERTISE BASED RANDOMISATION – THEREFORE EVALUATION OF
TECHNIQUE, ELIMINATING CONFOUNDING VARIABLES (SURGEONS
LEARNING CURVE)
• HIGH RISK PATIENTS INCLUDED
LIMITATIONS OF THE STUDY
• EXPERTISE BASED RANDOMISATION – LIMITS APPLICABILITY
OF FINDINGS
• SPECIFIC COSTS OF CABG SUPPLIES (OPCAB RETRACTOR,
CPB CIRCUITS) NOT INCLUDED
• VARIABLE COSTS OF SUPPLIES ACROSS HOSPITALS
GENERAL DISCUSSION POINTS
• WHO SHOULD BE PERFORMING OPCAB?
• WHICH PATIENTS SHOULD RECEIVE OPCAB?