This document summarizes recent evidence on medical treatments, percutaneous coronary intervention (PCI), and coronary artery bypass grafting (CABG) for stable coronary artery disease. Key findings include: 1) Large clinical trials found no significant difference in outcomes between PCI and optimal medical therapy for stable CAD patients. 2) CABG was shown to reduce mortality, myocardial infarction, and repeat revascularization compared to medical therapy or PCI for multi-vessel disease. 3) For left main coronary artery disease, CABG may be preferable to PCI for patients with high anatomical complexity scores. 4) Ongoing trials like ISCHEMIA are further evaluating optimal revascularization strategies for stable CAD patients with ischemia.

1. Medical treatment, PCI, or CABG
for Stable CAD ?
8/2/2016

2. • Medical treatments of coronary artery disease have improved
in the past decade because of the availability of statins,
effective blood pressure lowering drugs and antiplatelet
agents.
• In addition, improvements in PCI have revolutionised the
management of high risk people with acute myocardial
infarction (primary PCI and rescue PCI), non-ST elevation
myocardial infarction and unstable angina.
• The use of stents, together with antiplatelet and
antithrombotic treatments, has reduced procedural
complications and made PCI safer.

3. • DESs have reduced restenosis after PCI, although they
increase late stent thrombosis, for which long term dual
antiplatelet treatment is required.
• Improvements in coronary artery bypass (CABG) surgery have
been slow because only a few randomised controlled trials
have been performed.
• Surgeons still debate the benefits of off-pump CABG (beating
heart surgery) versus on-pump surgery, and whether double
internal mammary artery grafts are superior to single internal
mammary grafting.

4. • IHD represents as a dynamic continuum of disease with a
variable natural history that may, over decades, encompass
many phases of clinical expression ranging from asymptomatic
periods, development of chronic exertional angina,
subsequent quiescent periods, progression to accelerating
angina, and culmination in unstable angina, acute MI, or
sudden cardiac death.
• Therefore the approach to treatment should be tailored to the
individual patient’s clinical status.

5. Risk Stratification Based on Noninvasive Testing
2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/ STS guideline for the diagnosis and management of patients with stable ischemic
heart disease: Circulation. 126:e354, 2012.

6. (Data from Califf RM, Armstrong PW, Carver JR, et al: Task Force 5: Stratification of patients into high-, medium-,
and low-risk subgroups for purposes of risk factor management. J Am Coll Cardiol 27:964, 1996.)

7. Patient Selection for Revascularization
• Each of the following considerations may be used to guide
decisions regarding the indications for as well as the approach
to revascularization:
– Presence and severity of symptoms
– Physiologic significance of the coronary lesions and other anatomic
considerations
– Extent of myocardial ischemia and the presence of LV dysfunction
– Other medical conditions that influence the risks associated with
percutaneous or surgical revascularization.

8. PCI vs OMT

9. The 4.6-year cumulative primary-event rates were 19.0% in the PCI group and 18.5% in the
medical-therapy group (hazard ratio for the PCI group, 1.05; 95% confidence interval [CI], 0.87
to 1.27; P=0.62).
There were no significant differences between the PCI group and the medical-therapy group in
the composite of death, myocardial infarction, and stroke (20.0% vs. 19.5%; hazard ratio, 1.05;
95% CI, 0.87 to 1.27; P=0.62); hospitalization for acute coronary syndrome (12.4% vs. 11.8%;
hazard ratio, 1.07; 95% CI, 0.84 to 1.37; P=0.56); or myocardial infarction (13.2% vs. 12.3%;
hazard ratio, 1.13; 95% CI, 0.89 to 1.43; P=0.33).

12. Subgroup Analysis

13. Recruitment was halted prematurely after enrollment of 1220 patients (888 who underwent
randomization and 332 enrolled in the registry) because of a significant between-group
difference in the percentage of patients who had a primary end-point event: 4.3% in the PCI
group and 12.7% in the medical-therapy group (hazard ratio with PCI, 0.32; 95% confidence
interval [CI], 0.19 to 0.53; P<0.001).
The difference was driven by a lower rate of urgent revascularization in the PCI group than in
the medical-therapy group (1.6% vs. 11.1%; hazard ratio, 0.13; 95% CI, 0.06 to 0.30; P<0.001);
in particular, in the PCI group, fewer urgent revascularizations were triggered by a myocardial
infarction or evidence of ischemia on electrocardiography (hazard ratio, 0.13; 95% CI, 0.04 to
0.43; P<0.001).

14. • All patients were prescribed aspirin at a dose of 80 to 325 mg
daily, metoprolol at a dose of 50 to 200 mg daily (or any other
beta-1–selective blocker, alone or in combination with a
calcium-channel blocker or a long-acting nitrate), lisinopril (≥5
mg daily, or another angiotensin-converting–enzyme [ACE]
inhibitor or an angiotensin II–receptor blocker if the patient
had unacceptable side effects with the ACE inhibitor), and
atorvastatin (20 to 80 mg daily, or another statin of similar
potency alone or in combination with ezetimibe, to reduce
the low-density-lipoprotein [LDL] level to less than 70 mg per
deciliter [1.8 mmol per liter]).

17. 12 randomized clinical trials enrolling 7182 participants who fulfilled our inclusion criteria.
For the primary analyses, when compared with OMT, PCI was associated with no significant
improvement in mortality (risk ratio [RR], 0.85; 95% CI, 0.71-1.01), cardiac death (RR, 0.71;
95% CI, 0.47-1.06), nonfatal myocardial infarction (RR, 0.93; 95% CI, 0.70-1.24), or repeat
revascularization (RR, 0.93; 95% CI, 0.76-1.14), with consistent results over all follow-up time
points.
However, for freedom from angina, there was a significant improved outcome with PCI, as
compared with the OMT group (RR, 1.20; 95% CI, 1.06-1.37), evident at all of the follow-up
time points.

23. Extended survival information was available for 1211 patients (53% of the original population).
The median duration of follow-up for all patients was 6.2 years (range, 0 to 15); the median
duration of follow-up for patients at the sites that permitted survival tracking was 11.9 years
(range, 0 to 15).
A total of 561 deaths (180 during the follow-up period in the original trial and 381 during the
extended follow-up period) occurred: 284 deaths (25%) in the PCI group and 277 (24%) in the
medical-therapy group (adjusted hazard ratio, 1.03; 95% confidence interval, 0.83 to 1.21;
P=0.76).

24. PCI vs CABG

25. The CABG group had significantly lower mortality than the medical treatment group at 5 years
(10.2 vs 15.8%; odds ratio 0.61 [95% CI 0.48-0.77], p = 0.0001), 7 years (15.8 vs 21.7%; 0.68
[0.56-0.83], p < 0.001), and 10 years (26.4 vs 30.5%; 0.83 [0.70-0.98]; p = 0.03). The risk
reduction was greater in patients with left main artery disease than in those with disease in
three vessels or one or two vessels (odds ratios at 5 years 0.32, 0.58, and 0.77, respectively).

26. Impact of Coronary Artery Bypass Surgery versus Medical
Therapy on Survival

27. Effects of CABG on Survival

42. Left Main Disease

43. Major adverse cardiac and cerebrovascular event rates at 1 year in LM patients were similar
for CABG and PCI (13.7% versus 15.8%; Delta2.1% [95% confidence interval -3.2% to 7.4%];
P=0.44). At 1 year, stroke was significantly higher in the CABG arm (2.7% versus 0.3%; Delta-
2.4% [95% confidence interval -4.2% to -0.1%]; P=0.009]), whereas repeat revascularization
was significantly higher in the PCI arm (6.5% versus 11.8%; Delta5.3% [95% confidence interval
1.0% to 9.6%]; P=0.02); there was no observed difference between groups for other end
points.
When patients were scored for anatomic complexity, those with higher baseline SYNTAX
scores had significantly worse outcomes with PCI than did patients with low or intermediate
SYNTAX scores.

44. Major adverse cardiac and cerebrovascular event rates at 5 years was 36.9% in PCI
patients and 31.0% in CABG patients (hazard ratio, 1.23 [95% confidence interval, 0.95-1.59];
P=0.12).
Mortality rate was 12.8% and 14.6% in PCI and CABG patients, respectively (hazard ratio, 0.88
[95% confidence interval, 0.58-1.32]; P=0.53).
Stroke was significantly increased in the CABG group (PCI 1.5% versus CABG 4.3%; hazard ratio,
0.33 [95% confidence interval, 0.12-0.92]; P=0.03) and repeat revascularization in the PCI arm
(26.7% versus 15.5%; hazard ratio, 1.82 [95% confidence interval, 1.28-2.57]; P<0.01).
Major adverse cardiac and cerebrovascular events were similar between arms in patients with
low/intermediate SYNTAX scores but significantly increased in PCI patients with high scores
(≥33).

45. Unresolved Questions

46. • ISCHEMIA is an NHLBI-funded international randomized controlled
trial comparing the effectiveness of two initial management
strategies in 8,000 patients with moderate or severe ischemia: an
invasive strategy with cardiac catheterization and optimal
revascularization plus OMT versus a conservative strategy with OMT
alone and cath reserved for patients who fail medical therapy.
• The primary aim of the ISCHEMIA trial is to determine whether the
invasive strategy will reduce cardiovascular death or nonfatal
myocardial infarction as compared with the conservative strategy.
• Patients who qualify on the basis of ischemia and have normal renal
function will undergo blinded coronary CT angiography (CCTA) to
exclude left main disease and to confirm the presence of
obstructive coronary artery disease prior to randomization.
• Eligible patients are then randomized to the invasive or
conservative strategy

47. • Accrual is projected to last 4 years with a minimum 1.5 years and
maximum 6 years of follow-up.
• Patients randomized to the invasive group will undergo optimal
revascularization—PCI or CABG—as recommended by the local
interventional cardiologist and cardiovascular surgeon based on
protocol recommendations.
• Patients randomized to the conservative strategy will be permitted
to undergo invasive management as needed for refractory angina
or acute coronary syndrome.
• The protocol is designed to minimize unnecessary cath in patients
randomized to the conservative strategy.
• The primary outcome measure is time to cardiovascular death or
nonfatal MI.
• Secondary outcome measures will include quality of life, cost-
effectiveness, and cardiovascular hospitalizations.
• Enrollment began in late 2012.

49. Revascularization to Improve Survival Compared With Medical
Therapy

50. Revascularization to Improve Survival Compared With Medical
Therapy

51. Revascularization to Improve Survival Compared With Medical
Therapy

52. Revascularization to Improve Symptoms With Significant Anatomic (>50% Left Main
or >70% Non–Left Main CAD) or
Physiological (FFR <0.80) Coronary Artery Stenoses

53. Conclusions
• In patients with multivessel coronary disease, CABG does not
only lead to a dramatic reduction in repeat revascularization
and MACCE but also leads to a 27% reduction in long-term all-
cause mortality and a 42% reduction in MIs compared with
PCI.
• The benefits were not only observed in trials of diabetic
patients but also in trials where the great majority of patients
were nondiabetic.
• Use of bare-metal or drug-eluting stents did not alter the
mortality benefit.
• The three approaches should complement one another, not
compete.