TRIALS IN OPCAB - OPCAB VS ON PUMP CABG

TRIALS in OPCAB - OPCAB Vs On Pump CABG

 

ROOBY Trial –

 

Randomized On/Off Bypass Trial

The largest randomized controlled study of off-pump versus on-pump CABG

A prospective, single-blinded randomized trial

2203 patients in 18 medical centers and 53 attending surgeons.

In OPCAB group :

• mean age - 63 years
• females - 0.6%
• previous CABG - 0.8%
• peripheral arterial disease -16%
• 59% had EF > 54%,
• current smokers - 33%  
• the estimated risk of death before discharge or 30 days - 1.9%.

The OPCAB group received 2.9 grafts per patient

On-pump group received 3.0 grafts per patient

Transfusion was needed in 52% vs 56%

Hours in the operating room were 4.5 vs 4.4

Length of stay in hospital was 8.2 days vs 7.8 days  

 

Inclusion criteria –

 

Elective or urgent CABG cases

 

Exclusion criteria –

 

Emergent/salvage CABG

CABG + valve procedures

Patients with target vessels <1.1 mm and diffuse distal disease

 

Primary short-term end point –

 

Death and MACE in 30 days.

Primary long-term end points (30 days to 1 year) –

Death from any cause,

Nonfatal MI

Need for repeat revascularization

 

Secondary end points –

 

Completeness of revascularization

Graft patency at 1 year

Neuropsychological testing

 

Conclusion –

 

• The primary short-term composite outcome was seen in 7 % of OPCAB vs 5.6% in on-pump group
• The primary long-term composite outcome was seen in 9.9% vs 7.4%  
• OPCAB patients had fewer grafts.
• Death within 30 days was 1.6% vs 1.2%, all-cause death within 1 year was 4.1% vs 2.9% and cardiac death within 1 year was 2.7% vs 1.3%   
• After 1 year – Cardiac-related death (8.8% vs 5.9%) MACE (9.9% vs 7.4%) - significantly higher in OPCAB group.
• Graft patency was significantly lower in OPCAB group (82.6% vs 87.8%).
• Graft patency and effective revascularization at 1 year were significantly better with on pump CABG
• Graft patency – better in on pump CABG for all 3 major coronary regions and for arterial and vein conduits
• Sephaneous vein graft patency 76.6% vs 83.8 %
• At least one occluded graft was 36.5% vs 28.7%
• No difference in neuropsychogical testing between the groups.  

 

Drawbacks –

 

Female patients not included in the study

No data regarding low-density lipoprotein levels, use of statins and aspirin, whether glycemic control was practiced in these patients.

Also,12.4% is the conversion rate to on-pump CABG higher than STS database 2.2% - ROOBY OPCAB surgeons were inexperienced.

This high conversion rate was explained that ROOBY surgeons couldn’t be selective,did OPCAB because of randomization process.

Did not show benefit of OPCAB for postoperative renal function; however, <8% of the patients enrolled in this study had pre-existing CKD.

 

CORONARY Trial –

 

Coronary Artery Bypass Surgery Off or On Pump Revascularization Study

Prospective study

4752 patients randomized to on pump CABG or OPCAB in 79 centers and 19  countries.

As compared to ROOBY, CORONARY trial included -

• More female patients (19.2% vs. 0.5%),
• More patients with LM disease (21.5% vs. 0)
• More patients with 3 vessel disease (after excluding patients with LM disease) (74.2% vs. 66.6%).
• 44% patients were of South Asian or East Asian ethnic groups,known to have smaller coronaries.

 

2 coprimary outcomes were -  

 

A composite rate of death, nonfatal stroke, nonfatal MI or nonfatal new renal failure requiring dialysis at 30 days after randomization. This outcome was also assessed at 1 year.

1-year outcomes -also assessed nonfatal CVA and quality of life and neurocognitive function.

The second coprimary outcome - first coprimary outcome plus rate of repeat coronary revascularization at a mean of 5 years.

All deaths in the first 30 days were considered to be cardiovascular-related deaths.

 

Conclusion –

 

After 1 year- no difference in primary outcome event rate (12.1% OPCAB vs 13.3% on-pump)

No significant differences in incidence of recurrent angina (1.% vs 0.9%)

 Need for repeat revascularization was higher in OPCAB (1.4% vs 0.8%)

Quality of life - no significant difference

Neurocognitive function - no significant difference

CORONARY trial had double the number of participants than in ROOBY trial.

Experienced surgeons performed the surgeries.

Rate of crossover from OPCAB to on-pump was lower in the CORONARY trial suggesting surgical expertise.Still, the need for revascularization remained higher in the off-pump group.

 

SMART Trial –

 

The Surgical Management of Arterial Revascularization Therapy

Prospective, randomized, single center, single-surgeon trial.

297 patients randomized to OPCAB vs ONCAB

Compared graft patency, clinical outcomes, long-term survival ,health related quality of life, and costs.

After 7.5 years of follow-up, no difference in mortality or late graft patency in both groups.

No differences in late survival, 1-year graft patency (93.6% for OPCAB vs. 95.8% for ONCAB), recurrent angina or repeat revascularization

 

PRAGUE 4 Trial -

 

Compared 1-year angiographic patency of bypass grafts done off pump with those done on pump.

Patency of grafts done on beating heart is excellent and equal to grafts done on pump.

Off-pump CABG in unselected patients results in fewer patent saphenous grafts per patient.

 

Danish On-Pump versus Off-Pump Randomization Study (DOORS) -

 

On pump versus off pump CABG in elderly patients

Multicenter, randomized trial

900 patients >70 years of age to On pump CABG or OPCAB surgery.

After 30 days - end point of death, stroke or MI was assessed.

At baseline and 6 months postoperatively, self-assessment of quality of life was done.

6-month follow-up of mortality was performed through Danish National Registry.

The combined end point at 30 days was 10.2% for on pump CABG and 10.7% for OPCAB.

At the 6-month follow-up, mortality was 4.7% vs 4.2%.

Both groups had significant improvement in self-assessed health-related quality of life.

 

German Off-Pump CABG in Elderly (GOPCABE) trial -

 

RCT of patients >75 years

No difference in early mortality, stroke or MI between OPCAB and ONCAB

 

 

References –

 

Harold L. Lazar, Should off pump coronary artery bypass grafting be abandoned ? Circulation. 2013;128:406-413

Brack Hattler et al Off-Pump Coronary Artery Bypass Surgery Is Associated With Worse Arterial and Saphenous Vein Graft Patency and Less Effective Revascularization Results From the Veterans Affairs Randomized On/Off Bypass (ROOBY) Trial Circulation June 12, 2012

Anthony A.Bravy et al Randomized On/Off Bypass trial (ROOBY) The American College of Cardiology's Cardiosource.

Lakhmir S.Chawla et al.Off-Pump versus On-Pump Coronary Artery Bypass Grafting Outcomes Stratified by Preoperative Renal Function. J Am Soc Nephrol 2012 Aug; 23(8): 1389–1397.

Andre Lamy, Effects of Off-Pump and On-Pump Coronary Artery Bypass Grafting at 1 Year. N Engl J Med 2013; 368:1179-1188

Petr Widimsky, A randomized Comparison between off pump and on pump surgery angiographic results of PRAGUE 4 Trial. Circulation. 2004;110:3418-3423

Kim Houlind, Results from the Danish on pump versus off pump randomization study. Circulation. 2012;125:2431-2439

Bobby Yanagawa,The future of Off pump coronary artery bypass grafting : a North American perspective J Thorac Dis 2016 Nov; 8(Suppl 10): S832–S838.

 

- by Dr Amarja