Supplemental (Online-Only) Material

Appendix E1. Variables Considered in Multivariable Analyses

Demographics

Age (y), sex, race (white, black, other), weight (kg), height (cm), weight/height ratio, body surface area (m2), body mass index (kgm-2)

Status/symptoms

New York Heart Association functional class (I-IV), emergency operation

Cardiac comorbidity

Prior myocardial infarction, atrial fibrillation or flutter, heart failure

Noncardiac comorbidity

Treated diabetes, peripheral arterial disease, carotid disease, hypertension, history of smoking, prior stroke, cholesterol (mgdL-1), triglycerides (mgdL-1), creatinine (mgdL-1)

Coronary anatomy

Number of coronary systems diseased (50% stenosis), left anterior descending (LAD) disease (50%, moderate [50% to 69%], severe [70%]), left circumflex (LCx) system disease (50%, moderate [50% to 69%], severe [70%]), right coronary artery (RCA) system disease (50%, moderate [50% to 69%], severe [70%]), diagonal (Dg) disease (50%, moderate [50% to 69%], severe [70%]), location of moderate CAD (LAD, Dg, LCx, RCA)

Coronary artery bypass grafting procedures

Number of internal thoracic artery (ITA) grafts used to graft severely stenosed arteries (none, 1, 2), conduit used to bypass moderate CAD (none, ITA, saphenous vein [SV] graft, radial artery, other), graft locations (LAD, LAD diagonals, LCx territory, RCA territory), interaction terms for conduit used to bypass moderate CAD in each location (none, ITA, SV)

Support

Cardiopulmonary bypass (off-pump versus on-pump), bypass time (min)

Experience

Date of operation (years since January 1, 1972)

Table E1. Postoperative Angiograms Available for Analysis

Time from Index CABG

>0

3 mo

6 mo

1 y

5 y

10 y

15 y

20 y

Nongrafted native vessel

# Patients

489

477

469

422

260

134

66

21

# Angios

683

665

648

578

338

164

72

22

ITA-grafted native vessel

# Patients

371

357

351

337

237

112

34

6

# Angios

541

520

509

481

322

141

38

6

SV-grafted native vessel

# Patients

957

921

899

842

607

307

100

14

# Angios

1,371

1,325

1,295

1,216

836

402

124

18

Grafts

# Patients (ITA)

376

362

357

345

245

118

33

5

# Angios

560

538

527

499

334

149

39

5

# Patients (SV)

1,016

981

959

902

653

325

101

13

# Angios

1,467

1,420

1,390

1,310

907

429

127

17

Angios = angiograms; CABG = coronary artery bypass grafting; ITA = internal thoracic artery; SV = saphenous vein.

Table E2. Risk Factors Associated With Higher Likelihood of Having Higher Grade of Postoperative Stenosis (More Progression of Disease) in Left-sided Coronary Arteries versus Right Coronary Artery

Factor

Estimate SE

p

Overall

Younger age

-1.00 0.33

.003

Diabetes

0.42 0.195

.03

Peripheral arterial disease

0.53 0.23

.02

No prior stroke

-0.79 0.40

.05

Male

0.23 0.16

.17

Comparisons

No graft (left side)

reference

ITA graft (left side)

1.6 0.20