Appendix Update on Coronary Artery Bypass Surgery: Current and Future Trendsartery disease) compared with the medical therapy
available in that era [2]. However, the relatively high
morbidity and mortality rate associated with CABG
led to the development of PCI in the 1977. Tech-
niques of PCI have evolved to include coronary
artery stenting with bare-metal stents and, more
recently, drug-eluting stents. The use of PCI to treat
multivessel CAD rather than only single-vessel
disease led to several RCTs comparing PCI and
CABG [7].
The major results of a recent meta-analysis by
Brevata [8] reveal that early procedural mortality
rates (1.15% vs. 1.8%) and 5-year survival rates
(89.7% vs. 90.7%) are no different after PCI and
CABG. Brevata’s meta-analysis has been seriously
discredited by (1) the inclusion of the AWESOME
trial [14]; (2) inclusion criteria which were exclusion
criteria for other trials; and (3) inclusion of the
ERACI II trial [15] which had a 5.6% mortality and
fi nally the extent of the Stent or Surgery trial [16].
The latter favored CABG over PCI, but the trial was
terminated after 2 years because of lack of funding.
Also, the 5-year survival was similar after PCI and
CABG in patients with and those without diabetes
in the seven RCTs that reported on this subgroup.
Compared with PCI, CABG provided more com-
plete relief of angina in 5% to 10% of patients over
5 years, and repeated revascularization was less
common. However, more procedural strokes
occurred with the use of CABG than with PCI. Large
observational registries indicate that patients with
triple-vessel disease are much more likely to undergo
CABG. Patients with single vessel disease are more
likely to undergo PCI.
A post hoc analysis of the BARI (Bypass Angio-
plasty Revascularization Investigation) trial [17]
suggests that a diabetic subgroup of patients have a
longer post-procedure survival following CABG
than primary PCI. This is being tested prospectively
in the current BARI-2D study. Bravata and col-
leagues acknowledge the limitations of their meta-
analysis, which merely refl ect limitations in the
entry criteria, sample size, outcome assessment, and
reporting of available trials. For example, they could
not analyze procedural myocardial infarction
because of variable diagnostic criteria. Current tech-
niques and devices, including drug-eluting stents,
were not evaluated, and few patients older than
75 years or with poor left ventricular function, clini-
cal instability, or previous revascularization were
included in the trial.
The fi ndings of Bravata and colleagues [8] cannot
be generalized to all patients with coronary artery
disease, but are most applicable to patients with
intermediate disease severity, who constituted most
participants. The short-term and long-term mortal-
ity rates associated with stable anti-ischemic therapy
including PCI and CABG, are similar in these
patients in discussing revascularization options with
their patients; physicians should make this equiva-
lence clear, because patients often have preconceived
notions that one procedure or the other is superior.
The advantages of CABG are better relief of angina
and a lower likelihood of subsequent revasculariza-
tion; however, the magnitude of the latter benefi t
may decrease in future randomized trials that
include drug-eluting stents. The increase in stroke
with CABG offsets these advantages. Physicians
must ensure that their patients understand these dif-
ferences. Another major factor is the cost effective-
ness of the three major strategies. New quality of life
data from the COURAGE trial will be published
shortly.
For many patients, however, the most important
question is whether neither PCI nor CABG is war-
ranted. Until recently, recommendations for PCI or
CABG in patients other than those in the highest risk
group were based on observational data and consen-
sus opinion [2].
Newer studies have challenged the frequently
held assumptions that revascularization with CABG
or PCI consistently reduces cardiac events and
prolongs survival [18]. The recently published
COURAGE trial indicates that patients with moder-
ate to severe angina pectoris do not benefi t from
primary PCI strategy compared with OMT in rela-
tion to primary endpoints of death or myocardial
infarction when compared to PCI alone. The OAT
(Occluded Artery Trial) enrolled 2166 patients who
had an occluded infarct-related coronary artery
early after myocardial infarction and another high-
risk criterion, such as proximal stenosis in a differ-
ent coronary artery [18]. In OAT, PCI did not confer
an advantage over medical therapy for the combined
end-point of death, reinfarction, or New York Heart
Association class IV heart failure.
The COURAGE (Clinical Outcomes Utilizing
Revascularization and Aggressive Drug Evaluation)