This article was published on October 31,2016, at NEJM.org

BACKGROUNDLeft main coronary artery disease is associated

with high morbidity and mortality owing to the large amount of myocardium at risk.

European and U.S. guidelines recommend that most patients with left main coronary artery disease undergo coronary-artery bypass grafting (CABG).

Randomized trials have suggested that percutaneous coronary intervention (PCI) with drug-eluting stents might be an acceptable alternative for selected patients with left main coronary disease.

DW Park, KB Seung, YH Kim, et al.: Long-term safety and efficacy of stenting versus coronary artery bypass grafting for unprotected left main coronary artery disease: 5-year results from the MAIN-COMPARE (Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty Versus Surgical Revascularization) registry. J Am Coll Cardiol. 56:117-124 2010

Randomized studies of PCI vs Surgery for LMCA disease

Clinical Outcomes

PRECOMBAT TRIAL-5 YRS SYNTAX TRIAL-5 YRS

Surgery(N = 300)

Stents(N = 300) HR (95% CI) P value Surgery

(N = 348)Stents

(N = 357) HR (95% CI) P value

MACCE 14% 18% 1.27 (0.84-1.90) .26 31% 37% 1.23 (0.95-

1.59) .12

All death/stroke/MI

10% 8% 0.89 (0.52-1.52) .66 21% 19% 0.91 (0.65-

1.27) .57

All death 8% 6% 0.73 (0.39-1.37) .32 15% 13% 0.88 (0.58-

1.32) .53

Cardiac death

7% 4% 0.54 (0.26-1.13) .10 7% 9% 1.23 (0.71-

2.11) .46

Stroke 1% 1% 0.99 (0.14-7.02) .99 4% 2% 0.33 (0.12-

0.92) .03

MI 2% 2% 1.20 (0.37-3.93) .76 5% 8% 1.67 (0.91-

3.10) .10

Revascularization

5.5% 11.4%2.11

(1.16-3.84)

.01 16% 27%1.82

(1.28-2.57)

<.001

Guidelines Class of Recommendation LOE

ACC/AHA 2011

IIa—For SIHD when both of the following are present: B

1.Anatomic conditions associated with a low risk of PCI procedural complications and a high likelihood of good long-term outcome (e.g., a low SYNTAX score [≤22], ostial or trunk left main stenosis)

2.Clinical characteristics that predict a significantly increased risk of adverse surgical outcomes (e.g., STS-predicted risk of operative mortality ≥ 5%)

IIb—For SIHD when both of the following are present: B

1.Anatomic conditions associated with a low to intermediate risk of PCI procedural complications and an intermediate to high likelihood of good long-term outcome (e.g., low-intermediate SYNTAX score <33, bifurcation left main stenosis)

2.Clinical characteristics that predict an increased risk of adverse surgical outcomes (e.g., moderate-severe COPD, disability from prior stroke, or prior cardiac surgery; STS-predicted risk of operative mortality >2%)

III—For SIHD in patients (vs. performing CABG) with unfavorable anatomy for PCI and who are good candidates for CABG B

ESC 2014

IIa—Left main (isolated or 1VD, ostium/shaft) B

IIb—Left main (isolated or 1VD, bifurcation)/left main + 2VD or 3VD, SYNTAX score ≤32 B

IIIb—Left main + 2VD or 3VD, SYNTAX score ≥33

Conclusions of the data available● At one year and longer, CABG and PCI appear to have similar

rates of the combined end point of death from any cause, MI, stroke.

● As the complexity of associated coronary artery disease increases, assessed either by the SYNTAX score or as the number of vessels that need revascularization, the benefit in favour of CABG over PCI with stenting increases. 

For patients with lower complexity coronary disease who can undergo PCI at an acceptable risk and with reasonable probability for success, PCI may be an acceptable or even preferred option.

Still more data are available to validate this approach,

However, guidelines indicate that CABG should remain the preferred option. 

Conclusions of the data available

CABG is associated with a significantly higher incidence of adverse in-hospital outcomes, including death, MI, and stroke. However, the long-term rates of death, MI, and stroke are comparable or better depending on severity of associated coronary artery disease.

PCI with stenting is associated with a higher incidence of target vessel revascularization at long-term follow-up.

WHY A NEW TRIAL??The outcomes of PCI were acceptable only in the patients with

coronary artery disease of low or intermediate anatomical complexity.

Because SYNTAX results represented a subgroup of a subgroup, they were hypothesis generating.

PRECOMBAT and others were not adequately powered.

Routine angiographic follow up in PRECOMBAT

Moreover, contemporary metallic drug-eluting stents have a better safety and efficacy profile than do the first-generation stents used in earlier trials.

Surgical techniques and outcomes have also continued to improve, and an evaluation of alternative methods of revascularization for patients with left main coronary artery disease is warranted in a contemporary trial.

This article was published on October 31,2016, at NEJM.org

Trial designEXCEL was an International, Open-label, Multicenter (126 sites in 17 countries)Randomized Trial Compared Everolimus-eluting stents with CABG in

patients with LMCA disease.Interventional cardiologists and cardiac surgeons

were represented equally

SPONSORSHIP

The trial was sponsored by Abbott Vascular, which participated in the design of the protocol and in the selection and management of the sites

but was not involved in the writing of the drafts of the manuscript or in the management or analysis of the data

Inclusion criteria1a. Unprotected LMCAD with angiographic diameter stenosis ≥70% (visually estimated),

or with angiographic diameter stenosis ≥50% but <70% with one or more of the following present:

a. Non-invasive evidence of ischemia referable to a hemodynamically significant left main lesion, and/or

b. IVUS MLA ≤6.0 mm2, and/or

c. FFR ≤0.80 OR

1b. LM equivalent disease: Left main distal bifurcation Medina 0,1,1 disease, in the absence of significant angiographic stenosis in the left main coronary artery, may also be randomized if either of the following conditions are present:

i. Both the ostial LAD and ostial LCX stenoses are ≥70% stenotic by visual estimation, or

ii. If one or both of the ostial LAD and ostial LCX stenoses are ≥50% - <70% stenotic by visual estimation, then this lesion(s) is demonstrated to be significant either by

i. non-invasive evidence of ischemia in its myocardial distribution; and/or

ii. FFR ≤0.80; and/or

iii. IVUS MLA ≤4.0 mm2 (FFR is preferred).

Inclusion criteria2. Clinical and anatomic eligibility for both PCI and CABG as

agreed to by the local Heart Team (interventionalist determines PCI appropriateness and eligibility; cardiac surgeon determines surgical appropriateness and eligibility)

3. ≥18 years of age

4. Ability to sign informed consent and comply with all study procedures , including follow-up for at least three years

Randomization was performed with the use of an interactive voice-based or Web-based system in block sizes of 16, 24, or 32, with stratification according to diabetes (present vs. absent), SYNTAX score (≤22 vs. ≥23), and study center.

Treatment strategy-PCI The goal of PCI was complete revascularization

of all ischemic territories with the use of fluoropolymer- based cobalt–chromium everolimuseluting stents (XIENCE, Abbott Vascular).

Intravascular ultrasonographic guidance was strongly recommended.

The use of heparin or bivalirudin was allowed for procedural anticoagulation, and the use of glycoprotein IIb/IIIa inhibitors was discouraged. Dual antiplatelet therapy was initiated before PCI and was continued for a minimum of 1 year thereafter.

Treatment strategy-CABG CABG was performed with or without

cardiopulmonary bypass (discretion of the operator). The goal of CABG was complete anatomical

revascularization of all vessels 1.5 mm or larger in diameter in which the angiographic diameter stenosis was 50% or more; the use of arterial grafts was strongly recommended.

Epiaortic ultrasonography and transesophageal ultrasonography were recommended to assess the ascending aorta and ventricular and valvular function. Aspirin was administered during the perioperative period, and the use of clopidogrel during follow-up was allowed, but not mandatory, according to the local standard of care.

Objectives and End Points

PRIMARY ENDPOINT OUTCOME

Composite rate of death from anycause, stroke, or myocardial infarction at 3 years

Whether PCI was non-inferior to CABG(The non-inferiority margin of 4.2 percentage points)

Objectives and End Points

SECONDARY OUTCOMES1)Composite rate of death from anycause, stroke, or myocardial infarction at 30 days(Non-inferiority margin=2%)

2) Death, stroke , MI or Ischemia driven revacularization at 3 years

(Non-inferiority margin=8.4%)

Objectives and End PointsADDITIONAL SECONDARY OUTCOMES included The individual components of the primary end pointRevascularization, Stent thrombosis,Symptomatic graft stenosis or occlusion,Bleeding complications, and A pre-specified composite of periprocedural major

adverse events.

RESULTS

Baseline angiographic core laboratory assessment

Procedural data

Medicines used

Medicines used

Medicines used

End point PCIN=948

CABGN=957

DIFFERENCE IN EVENT RATE

P-VALUE FOR NON-INFERIORITY

HAZARD RATIO (95% CI)

P-VALUE FOR SUPERIORITY

PRIMARY END POINT

NO % NO % %points (upper confidence limit)

DEATH,STROKE, MI AT 3 YRS

137 15.4 135 14.7 0.7% (4.0)

0.02

SECONDARY END POINTS

DEATH,STROKE,MI AT 30 DAYS

46 4.9 75 7.9 -3.1(-1.2) <0.001

DEATH,STROKE,MI OR ISCHEMIA DRIVEN REVASC AT 3 YRS

208 23.1 174 19.1 4.0 (7.2) 0.01

DEATH,STROKE.MI AT 3 YRS

137 15.4 135 14.7 - - 1.00(0.79-1.26)

0.98

Stone GW et al. N Engl J Med 2016. DOI: 10.1056/NEJMoa1610227

Time-to-Event Curves for the Primary Composite End Point and its Components.

Stone GW et al. N Engl J Med 2016. DOI: 10.1056/NEJMoa1610227

Subgroup Analyses of the Primary Composite End Point.

Clinical endpoints at 30 days

Primary and hierarchical secondary endpoint events occurring within the first 30 days and between 30 days and 3 years

SUMMARY

Large Scale RCT – LMCA- PCI WITH XIENCE VS CABG PRIMARY OUTCOME : DEATH+STROKE+MI AT 3 YEARS- PCI NON-INFERIOR

At 30 days PCI was better in terms of less infections/ procedure related complications esp periprocedural MI / Bleeding

At 30 days, Death, Stroke and MI were lesser with PCI But between 30 days and 3 years these were more common with PCI PLUS ischemia related revascularization was more common with PCI at 3 years

Limitations

Longer follow-up required Long term difference in medication Blinding of patients and investigators to the

treatments assigned was not possible 24% patients had syntax >32 – furthur studies

are warranted in this subset

EXCEL VS SYNTAX

Syntax was hypothesis generating as it was a post hoc analysis and not a pre-specified analysis.

First generation stents were used in syntax (higher risk of ST)

IVUS was not used that frequentlyCABG – also showed improvements in EXCEL with

greater use of off-pump surgery, arterial grafts anf transesophageal echo , as compared to SYNTAX.

Periprocedural MI definition was standardized >10 times ULN

CONCLUSION TAKE HOME MESSAGE

For the treatment of patients with left main

coronary artery disease and low or intermediate

SYNTAX scores, PCI with everolimus- eluting

stents was NONINFERIOR to CABG with respect

to the composite of death, stroke, or myocardial

infarction at 3 years

THANKS!

LANCET31OCT 2016

THANKS!

STATISTICAL ANALYSIS

All principal analyses were performed with data from the time of randomization in the intention to-treat population, which included all patients according to the group to which they were randomly assigned, regardless of the treatment received.

Sensitivity analyses were performed in the per-protocol and as-treated populations.

Event rates were based on Kaplan–Meier estimates in time-to-first-event analyses.

Noninferiority was calculated with the use of the Com– Nougue approach to estimating the z statistic for the Kaplan–Meier failure rates, with standard errors estimated by means of Greenwood’s formula.

In time-to-first-event analyses, hazard ratios with 95% confidence intervals were determined, and event rates were compared with the use of the log-rank test.

Categorical variables were compared with the use of the chi-square test or Fisher’s exact test.

Continuous variables were compared with the use of Student’s t-test or the Wilcoxon rank-sum test for non-normally distributed data.

For superiority, a two-sided P valueof 0.05 or less was considered to indicate statistical significance.

All statistical analyses were performed with the use of SAS software, version 9.4 (SAS Institute).