The AHA Guidelines and Scientific Statements Handbook

Appendix

Update on Coronary Artery Bypass

Surgery: Current and Future Trends

Robert A. O’Rourke

CABG or PCI vs. OMT
CABG vs. PCI
Generalization
Observational studies
Specifi c subgroups
Lack of suffi cient RCT data

CABG or PCI vs. OMT

Coronary artery bypass graft (CABG) surgery and
catheter-based percutaneous coronary intervention
(PCI), with or without coronary stents, are alterna-
tive approaches to mechanical coronary revascular-
ization [1]. However, the comparative effectiveness
of CABG and PCI remains poorly defi ned for
patients in whom both procedures are technically
feasible and myocardial revascularization is clini-
cally indicated. Furthermore, the use of intensive
optimal medical therapy (OMT) of chronic stable
angina has never been proven to be inferior to revas-
cularization except in patients who are at high risk
for adverse cardiac events or who present with acute
coronary syndromes [1–6]. In 1994 Yusuf and asso-
ciates [7] performed a meta-analysis utilizing seven
randomized clinical trials comparing coronary
artery bypass graft surgery with an initial strategy of
medical therapy to assess the effect on mortality in
patients with stable coronary artery disease. These
patients had stable angina with no necessity for
initial surgery on grounds of symptoms alone or
myocardial infarction.

Patients (n = 1234) were assigned either for CABG

surgery or the standard of care at the time (n = 1325)

“meager management” considered suboptimal to

current standards (see Table A.1). Anti-angina drugs

such as beta-blockers, calcium blockers, ACE inhibi-

tors, and effective long-acting nitrates were generally

not available. Nevertheless, the proportion of

patients in the medical group who had undergone

CABG surgery was 25% in 5 years, 33% in 7 years,

and 41% in 10 years; 93.7% of patients assigned top

the surgical group underwent CABG surgery. The

CABG group had signifi cantly lower mortality than

the medical group at 5 years (10.2 vs. 15.8, P = 0.001)

and at 10 years (26.4 vs. 30.5%, P = 0.03). The risk

reduction was greater in patients with left main

coronary artery disease than in those with disease

in three vessels. PCI has never been shown to be

superior to CABG surgery for treatment of symp-

tomatic stable coronary disease.

CABG vs. PCI

In patients with left main or triple-vessel coronary

artery disease and reduced left ventricular function,

CABG is generally preferred because randomized,

controlled trials (RCTs) have shown that it improves

survival compared with medical therapy. The use of

intensive medical therapy for patients with stable

angina has never been shown to be inferior to OMT

in reducing recurrent myocardial infarction or

cardiac death.

Recently, Bravata and associates [8] sought to

evaluate the evidence from RCTs on the compara-

tive effectiveness of PCI and CABG. They included

trials using balloon angioplasty or coronary stents

because quantitative reviews have shown no

The AHA Guidelines and Scientific Statements Handbook
Edited by Valentin Fuster © 2009 American Heart Association
ISBN: 978 -1-405-18463-2