The AHA Guidelines and Scientific Statements Handbook

The AHA Guidelines and Scientifi c Statements Handbook

Background

Surgical revascularization for obstructive coronary
atherosclerotic heart disease (CASHD) offers relief of
angina, improvement in exercise tolerance, and sur-
vival benefi t [1]. Dedicated efforts over the last thirty
years aimed at seeking effective treatment for the
most common killer of humans in Western society
led to an eventual recognition of the value of coro-
nary artery bypass graft surgery (CABG). Through
three large, prospectively randomized multicenter
trials and several smaller studies, practitioners
learned that patients with triple-vessel disease, left
main disease, and CASHD with left ventricular (LV)
dysfunction found benefi t from surgery relative to
medical therapy. Results from these studies led to the
application of CABG to increasingly sicker patients.
Improvements in surgical and anesthetic tech-
niques have evolved such that the expected 30-day
mortality for elective CABG in the patient less than
65 years old with normal LV function is less than
1%. Progress has also been swift in the moderation

of perioperative morbidity, particularly central

nervous system (CNS) injury, the systemic insults of

cardiopulmonary bypass (CPB), infection, bleeding,

and renal function.

Nine randomized trials comparing surgery to

percutaneous transluminal coronary angioplasty

(PTCA) suggested that CABG provided better relief

of angina with a reduced need for subsequent pro-

cedures [1]. Late death and rate of myocardial

infarction were decreased in treated patients with

diabetes mellitus who underwent CABG [1]. Data

from large registries, particularly those of New York

State, suggest that patients with severe, proximal

LAD stenosis and/or triple-vessel disease may

achieve improved survival with CABG (Fig. 7.1;

Table 7.1). [1]. Since completion of these trials,

however, improvements in PTCA (i.e., stent design

and use, drug-eluting stents), surgery (more fre-

quent use of arterial grafts), and post-procedural

medical therapy have occurred.

Analysis of risk stratifi cation in CABG has identi-

fi ed seven core variables (i.e., urgency of operation,

Table 7.1 Three-year survival by treatment in each anatomic subgroup

Coronary anatomy group

Survival

Patients (n) Observed (%) Adjusted (%) P

1-Vessel, no LAD CABG
PTCA

507

11,233

89.2

95.4

92.4

95.3

0.003

1-Vessel, nonproximal LAD CABG
PTCA

153

4130

95.8

95.7

96.0

95.7

0.857

1-Vessel, proximal LAD CABG
PTCA

1917

5868

95.8

95.5

96.6

95.2

0.010

2-Vessel, no LAD CABG
PTCA

1120

2729

91.0

93.4

93.0

92.6

0.664

2-Vessel, nonproximal LAD CABG
PTCA

850

2300

91.3

93.3

92.3

93.1

0.438

2-Vessel, proximal LAD CABG
PTCA

7242

2376

93.5

92.8

93.8

91.7

<0.001

3-Vessel, nonproximal LAD CABG
PTCA

1984

660

90.1

86.7

90.3

86.0

0.002

3-Vessel, proximal LAD CABG
PTCA

15,873

634

90.1

88.2

90.3

86.1

<0.001

LAD indicates left anterior descending coronary artery; CABG, coronary artery bypass graft; and PTCA, percutaneous transluminal coronary angioplasty.
Comparative observed and adjusted 3-year survival of patients treated with PTCA or CABG in various anatomic subgroups.
Reprinted with permission from Elsevier Science, Inc. (Hannan et al. J Am Coll Cardiol. 1999;33:63–72).