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Disclosures/Conflicts
• The author is a cardiac surgeon.
• Royalties from coronary surgical
instruments invented by the author and
marketed by Scanlan, Inc.
• No other relevant financial COI’s.

Whatever Happened to OPCAB
John D. Puskas, MD, FACS, FACC
Professor, Quality Officer and Associate Chief
Division of Cardiothoracic Surgery, Emory University
AATS Annual Meeting
May 8, 2013
Minneapolis, MN

Why Should OPCAB Be Better
• CABG/CPB entails extracorporeal circulation, aortic
cannulation and clamping, global myocardial
ischemia, hypothermia, hemodilution etc.
• OPCAB avoids these deleterious effects of CPB by
mechanically stabilizing each coronary artery target
individually, while the rest of the heart beats and
supports normal physiologic circulation.
• If a complete revascularization with precise
anastomoses can be accomplished without CPB,
then the patient will benefit.

National Data Sample
• Non-emergent, isolated, primary CABGs
• ONCAB or OPCAB
• North American centers which each
performed >100 ONCAB and >100 OPCAB
cases between 1/1/2004 and 12/31/2005
• Time interval included all data available since
introduction of data field for conversions

Study Cohort (Intent-to-Treat)
• 42,477 consecutive patients:
16,245 OPCAB vs 26,232 CPB
• 63 North American centers, including 8 with
cardiothoracic residency programs
• Of the 16,245 OPCAB cases, 355 (2.2%) were
converted during surgery from an initial OPCAB
approach to ONCAB and were analyzed within the
OPCAB group.

Risk-Adjusted Odds Comparisons
OPCAB vs ONCAB:
Major Adverse Cardiac Events
Outcome Adjusted OR (95% CI) P-value
Death 0.83 (0.69, 0.98) 0.03
Stroke 0.65 (0.52, 0.80)

Risk-Adjusted Odds Comparisons
OPCAB vs ONCAB: Other Outcomes
Outcome Adjusted OR (95% CI) P-value
Renal Failure 0.74 (0.64, 0.86)

Off-Pump Coronary Artery Bypass
Disproportionately Benefits Patients With
Higher Society of Thoracic Surgeons Predicted
Risk Of Mortality
John D Puskas MD, Vinod Thourani MD, Patrick Kilgo MS*,
William Cooper MD, Thomas Vassiliades MS, J David Vega MD,
Cullen Morris MD, Edward Chen MD, Brian J Schmotzer BS*,
Robert A Guyton MD, Omar M Lattouf MD PhD
Emory University
Atlanta, USA
Society of Thoracic Surgeons
January 27, 2009
San Francisco

Methods
• The Society of Thoracic Surgeons (STS) database was
queried for all isolated, primary CABG cases between
1/1/97 and 12/31/07 at a US academic center.
• The STS Predicted Risk of Mortality (PROM), based on
30 preoperative risk factors, was used in three ways to
compare 30-day operative mortality between patients
treated with OPCAB versus CPB.

Results (1)
• There were 14766 consecutive patients; 7083
OPCAB (48.0%) and 7683 CPB (52.0%).
• There was no difference in operative mortality
between OPCAB and CPB for patients in the
lower two risk quartiles.
• In the higher risk quartiles there was a mortality
benefit for OPCAB (odds ratio 0.62 and 0.45 for
OPCAB in the third and fourth risk quartiles).

Results (2)
• In the highest risk quartile there was a large
mortality benefit for OPCAB:
(Odds Ratio 0.45; 95%CI 0.33-0.63; p

Conclusions
• OPCAB is associated with lower operative
mortality than CABG on CPB for higher risk
patients.
• This mortality benefit increases with
increasing STS Predicted Risk of Mortality.

Implications (1)
• These findings corroborate the preference of
many surgeons to perform OPCAB for
patients at high risk for mortality with
CABG/CPB.
• Explain why randomized controlled trials
enrolling predominantly low risk patients
have failed to show a mortality benefit for
OPCAB.

Off-Pump Coronary Artery Bypass
Disproportionately Benefits Higher Risk
Patients After Adjustment for Patient Factors,
Center Volume and Surgeon Identity
John D Puskas MD*, Sean S. O’Brien PhD**
and Xia He MS**
*Division of Cardiothoracic Surgery, Emory University and
**Duke Clinical Research Institute, Duke University
American Association for Thoracic Surgery
Annual Meeting 2012
San Francisco

Methods
• The STS National Cardiac Database queried for all isolated,
primary CABG cases between 1/1/2005 and 12/31/2010
• Of these 876,081 cases (“All Sites”), 210,469 were at
participant sites that performed >300 OPCAB and >300 CPB
cases during the 6-year study period (“High Volume Sites”).
• Operative mortality, stroke, ARF, M+M, and PLOS >=14d were
analyzed with conditional logistic models, stratified by
participant and by surgeon and adjusted for all 30 variables
that comprise the STS PROM score.

Results (1)
• OPCAB was associated with significant reduction in risk
of death, stroke, ARF, M+M and PLOS>14d, compared to
CABG/CPB after adjustment for 30 patient risk factors in
the overall sample.
• This held true within high volume centers alone, and was
somewhat more pronounced after adjustment for
surgeon effect.

Results (2)
• In the overall sample, there was a significant (p

Mortality or Major Morbidity For All Patients:
OPCAB vs CPB at Varying Levels of PROM

Results (3)
• In all PROM quartiles, OPCAB was associated with
significantly reduced risk of death and stroke.
• The magnitude of reduction increased with increasing PROM.
• Large volume centers had slightly lower risk of death and
stroke than lower volume centers.
• The relative reduction of risk of death and stroke with
OPCAB vs CPB was similar in high volume centers compared
to all centers.

Whatever Happened to OPCAB

ROOBY Trial Rebuttal
• VA ROOBY trial enrolled low-risk male patients in whom
avoidance of CPB was unlikely to greatly improve the
expected excellent outcomes.
• Most cases performed by residents, supervised by
attendings inexperienced in OPCAB and much more
experienced in ONCAB: 12.4% conversion rate 6x STS!
• Illogical to conduct a RCT comparing outcomes with
alternative surgical techniques among operators who have
grossly asymmetric experience and expertise with the two
techniques being compared.
• Wrong patients; wrong surgeons.

ACC March, 2013
26

CORONARY Trial
Lamy et al, NEJM 2012
• 4752 pts randomized at 79 centers in 19 countries
• Predominantly low and intermediate risk patients
• Primary endpoint: death, stroke, MI, RF
• Intention-to-treat analysis
• No signif difference at 30 days
(OPCAB 9.8% vs CPB 10.3%; HR 0.95, p=0.59)

Benefits of OPCAB in CORONARY
OPCAB associated with significant reduction in:
• Transfusion (50.7% vs 63.3%; RR 0.80; CI 0.75-0.85; p

Primary Outcome (%)
Primary outcome per EuroSCORE
15
HR 1.35
HR 0.87
HR 0.85
12
9
6
3
0
Off-pump On-pump Off-pump On-pump Off-pump On-pump
0-2 3 to 5 >5
P=0.047 interaction
EuroSCORE

Primary Outcome per EuroSCORE
OFF-PUMP
ON-PUMP

Hazard Ratio
Hazard Ratio Off-pump/On-pump
ROOBY
CORONARY
37

1 st Co-Primary Outcome (30 Days)
(830 patients)
Off Pump
%
On Pump
%
Hazard
Ratio
95% CI
p
value
Primary Outcome
Death, Stroke, MI, Renal Failure
Components
9.2 13.7 0.66 0.44-1.00 0.049
Death 1.4 1.4 1.01 0.33-3.13 0.98
Stroke 1.2 1.7 0.72 0.23-2.27 0.57
Non Fatal MI 7.5 10.6 0.70 0.44-1.11 0.13
New Renal Failure 0.2 1.0 0.25 0.03-2.25 0.22
* Not a pre-specified sub-group
38

CORONARY: The Coronary Artery Bypass
Grafting Surgery Off or On Pump
Revascularization Study
Results at 1 Year
André Lamy
Population Health Research Institute
Hamilton Health Sciences
McMaster University
Hamilton, CANADA
on behalf of the CORONARY Investigators
Disclosures: CORONARY was funded by a grant from the Canadian Institutes
of Health Research (CIHR).

1 st Co-Primary Outcome (1 Year)
Off Pump
%
On Pump
%
Hazard
Ratio
95% CI
p
value
Primary Outcome
Death, Stroke, MI, Renal Failure
Components
12.1 13.3 0.91 0.77-1.07 0.24
Death 5.1 5.0 1.03 0.80-1.32
Stroke 1.5 1.7 0.90 0.57-1.41
Non Fatal MI 6.8 7.5 0.90 0.73-1.12
New Renal Failure 1.3 1.3 0.97 0.59-1.60
40

Cumulative Event Rate
0.0 0.05 0.10 0.15 0.20
Death/MI/Stroke/New Renal Failure
at 1 Year
On Pump CABG
Off Pump CABG
HR 0.91
95% CI 0.77-1.07
p value 0.24
0 3 6 9 12
41

CORONARY:
Why No Difference in Stroke
• Surgeons opted to convert CPB patients
to OPCAB when they found a calcified
aorta (102 patients)

Etiology of Stroke in CABG
• AORTIC ATHEROEMBOLISM
• OTHER:
• Intraop hypotension, esp in setting of cerebrovascular disease
• Periop atrial fibrillation causing thromboembolism
• Postoperative hypotension or arrest
• Hemorrhagic stroke, esp associated with hypertension or
cerebral aneurysm (Bad Luck)

Etiology of Aortic Atheroembolism
• AORTIC MANIPULATION:
• Cannulation and De-cannulation
• Clamping
• Un-clamping
• Proximal anastomoses
• Late thromboembolism from aortic intimal
clamp injury
• OTHER:
• Bad luck

How Can We Reduce Aortic
Manipulation
• Limit or eliminate aortic clamping
• On-Pump CABG:
• Single clamp
• No clamp
• OPCAB:
• clampless OPCAB
• All-arterial with BITA inflow
• Clampless aortic proximals

Clampless OPCAB:
State of the Art CABG
Borgermann et al, Circulation 2012; 126:S176-182
• 395 consecutive clampless OPCAB (310 PAS-Port; 85 all-arterial
without proximals)
• Propensity Score matching on 15 preop risk variables to compare
outcomes among 394 pairs of clampless OPCAB vs cCABG:
In-hospital death
Stroke
Death or Stroke
(OR 0.25; 95% CI 0.05-1.18; p=0.08)
(OR 0.36; 95% CI 0.13-0.99; p=0.048)
(OR 0.27; 95% CI 0.11-0.67; p=0.005)
• 2 years F/U: death (OR 0.39; 95% CI 0.19-0.80; p=0.01), death or
stroke (OR 0.58; 95% CI 0.34-1.00; p=0.05)
• MACCE (OR 0.62; 95% CI 0.37-1.02; p=0.06)
• Repeat revascularization (OR 0.74; 95% CI 0.40-1.38; p=0.35)

Aortic No-Touch Technique Makes the
Difference in OPCAB
Emmert et al JTCCVS 2011; 142:1499-506.
• 2004-2009: 4314 patients, OPCAB 2203, cCABG 2111.
• Propensity-adjusted regression, OPCAB vs cCABG:
Composite respir/renal/bleed (OR 0.46; CI 95% 0.35-0.91; p

Aortic No-Touch Technique Makes the
Difference in OPCAB
Emmert et al JTCCVS 2011; 142:1499-506.
• Two OPCAB groups: PC n=567 vs HS n=1365
• Propensity-adjusted regression, HS vs PC:
Stroke
MACCE
(0.7% vs 2.3%; OR 0.39; CI 95% 0.16-0.90; p=0.04)
(6.7% vs 10.8%; OR 0.55; CI 95% 0.38-0.79; p=0.001)
• Stroke rate similar between cCABG and PC OPCAB

OPCAB Can Be Better Than
Conventional CABG on CPB
• Operator dependent procedure
• Different skill set, physically and psychologically
• It matters how you do it!
• Avoid aortic clamping to optimize benefit
• Multiple arterial grafts to optimize longevity
• Not for every patient or every surgeon.

Conclusions
• SYNTAX and FREEDOM 5-yr results demonstrate that
CABG is superior to PCI for most patients with complex
CAD, especially those with diabetes
• Outcomes with LM PCI in pts with low Syntax score are
favorable and have inspired the EXCEL trial.
• BITA grafting may be the single most effective therapy most
commonly denied patients with CAD
• OPCAB is operator-dependent and benefits high-risk patients
most; clampless OPCAB with multiple arterial grafts

Clampless CABG—How
• All inflow from ITAs (BITA grafting as a
strategy for reducing stroke)
• Clampless proximal anastomoses on the
ascending aorta
• Heartstring
• Novare
• PAS-port
• Cyclone

Conclusions
• SYNTAX and FREEDOM 5-yr results demonstrate that
CABG is superior to PCI for most patients with complex
CAD, especially those with diabetes, but stroke remains the
Achilles Heal of CABG
• Reducing stroke in CABG should be a high priority
• BITA grafting may be the single most effective therapy most
commonly denied patients with CAD
• OPCAB is operator-dependent and benefits high-risk patients
most; clampless OPCAB with multiple arterial grafts
• Multiple grafting techniques that avoid aortic clamping are
available and should become routine.

Whatever Happened to OPCAB
• To truly exploit the potential benefit of OPCAB
aortic manipulation should be minimized: no
partial clamp
• To optimize long-term benefit of CABG, BITA
and all-arterial grafting should be more
commonly practiced.
• We can and should do better OPCAB!