Table 1:
Baseline characteristics of the study cohort based upon presence of early revascularization (PCI or CABG within 90 days of test)
| Total | 90-day revascularization | P-Value | ||
|---|---|---|---|---|
| n =16029 | Yes n = 1277 |
No n = 14752 |
||
| Demographics and clinical risk factors | ||||
| Age, years | 68.6 ± 11.9 | 69.9 ± 10.8 | 68.5 ± 12.0 | < 0.001 |
| Male Sex | 8008 (50.0%) | 830 (65.0%) | 7178 (48.7%) | < 0.001 |
| Body mass index, kg/m2 | 29.59 ± 6.30 | 29.82 ± 5.77 | 29.57 ± 6.34 | 0.16 |
| Known CAD | 5225 (32.6%) | 647 (50.7%) | 4578 (31.0%) | < 0.001 |
| Prior MI | 2258 (14.1%) | 292 (22.9%) | 1966 (13.3%) | < 0.001 |
| Prior PCI | 3926 (24.5%) | 547 (42.8%) | 3379 (22.9%) | < 0.001 |
| Prior CABG | 1933 (12.1%) | 254 (19.9%) | 1679 (11.4%) | < 0.001 |
| Hypertension | 12794 (79.8%) | 1089 (85.3%) | 11705 (79.3%) | < 0.001 |
| Diabetes Mellitus | 4700 (29.3%) | 525 (41.1%) | 4175 (28.3%) | < 0.001 |
| Hyperlipidemia | 12414 (77.4%) | 1055 (82.6%) | 11359 (77.0%) | < 0.001 |
| Current Smoker | 2150 (13.4%) | 181 (14.2%) | 1969 (13.3%) | 0.41 |
| Family history of CVD | 6304 (39.3%) | 514 (40.3%) | 5790 (39.2%) | 0.48 |
| Peripheral Vascular Disease | 2252 (14.0%) | 237 (18.6%) | 2015 (13.7%) | < 0.001 |
| Cerebrovascular Accident | 1577 (9.8%) | 146 (11.4%) | 1431 (9.7%) | 0.05 |
| Prior Abnormal Calcium Score | 2068 (12.9%) | 98 (7.7%) | 1970 (13.4%) | < 0.001 |
| Atrial Fibrillation | 3184 (19.9%) | 189 (14.8%) | 2995 (20.3%) | < 0.001 |
| Patient Status | 0.52 | |||
| Inpatient | 6042 (37.7%) | 492 (38.5%) | 5550 (37.6%) | |
| Outpatient | 9987 (62.3%) | 785 (61.5%) | 9202 (62.4%) | |
| Abnormal Baseline ECG | 13481 (84.1%) | 1076 (84.3%) | 12405 (84.1%) | 0.87 |
| Symptoms on presentation | ||||
| Chest pain | < 0.001 | |||
| Atypical angina | 9333 (58.3%) | 781 (61.2%) | 8552 (58.0%) | |
| Typical angina | 140 (0.9%) | 31 (2.4%) | 109 (0.7%) | |
| Non-anginal chest pain | 90 (0.6%) | 7 (0.5%) | 83 (0.6%) | |
| None | 6458 (40.3%) | 458 (35.9%) | 6000 (40.7%) | |
| Dyspnea | 7880 (49.2%) | 674 (52.8%) | 7206 (48.8%) | 0.01 |
| Syncope | 1054 (6.6%) | 65 (5.1%) | 989 (6.7%) | 0.03 |
| Baseline Medications | ||||
| Aspirin | 10799 (67.4%) | 942 (73.8%) | 9857 (66.8%) | < 0.001 |
| Beta-blocker | 7236 (45.1%) | 679 (53.2%) | 6557 (44.4%) | < 0.001 |
| Statin | 5852 (36.5%) | 486 (38.1%) | 5366 (36.4%) | 0.23 |
| Calcium Channel Blocker | 3726 (23.2%) | 326 (25.5%) | 3400 (23.0%) | 0.04 |
| Long acting nitrates | 2066 (12.9%) | 251 (19.7%) | 1815 (12.3%) | < 0.001 |
| Stress and Perfusion Results | ||||
| Baseline Heart Rate, bpm | 70.0 ± 13.5 | 70.9 ± 13.4 | 70.0 ± 13.5 | 0.02 |
| Peak Heart Rate, bpm | 89.3 ± 16.5 | 89.2 ± 16.8 | 89.9 ± 16.5 | 0.87 |
| Rest Systolic BP, mmHg | 131.0 (117.0, 146.0) | 135.0 (120.0, 150.5) | 130.0 (117.0, 145.0) | < 0.001* |
| Peak Systolic BP, mmHg | 120.0 (107.0, 135.0) | 123.0 (109.0, 138.0) | 120.0 (107.0, 135.0) | < 0.001* |
| ECG Response | < 0.001 | |||
| Ischemic | 675 (4.2%) | 213 (16.7%) | 462 (3.1%) | |
| Non-Ischemic | 12099 (75.5%) | 722 (56.5%) | 11377 (77.2%) | |
| Non-Diagnostic | 3017 (18.8%) | 317 (24.8%) | 2700 (18.3%) | |
| Equivocal | 229 (1.4%) | 25 (2.0%) | 204 (1.4%) | |
| % Ischemic Myocardium | < 0.001 | |||
| 0% | 10127 (63.2%) | 33 (2.6%) | 10094 (68.4%) | |
| 1-9.9% | 3742 (23.3%) | 271 (21.2%) | 3471 (23.5%) | |
| ≥10% | 2160 (13.5%) | 973 (76.2%) | 1187 (8.0%) | |
| % Scarred Myocardium | 0.0 (0.0, 0.0) | 0.0 (0.0, 4.4) | 0.0 (0.0, 0.0) | < 0.001* |
| Transient ischemic dilation | 2047 (12.8%) | 456 (35.7%) | 1591 (10.8%) | < 0.001 |
| Rest LVEF, % | 61.0 ± 13.7 | 56.2 ± 13.6 | 61.4 ± 13.6 | < 0.001 |
| LVEF Reserve, % | 4.0 (0.0, 8.0) | 0.0 (−5.0, 5.0) | 4.0 (0.0, 8.0) | < 0.001* |
Continuous variables compared using Student's T-test or *Mann-Whitney U test for non-normally distributed variables.
Categorical variables compared using chi-square test.
MI=myocardial infarction, PCI=percutaneous coronary intervention, CABG=coronary artery bypass graft surgery, LVEF=left ventricular ejection fraction, transient ischemic dilation= Stress LV volume/Rest LV volume ratio >1.1