Table 1. Baseline Characteristics of Patients With and Without Stress-Induced Ischemia.
| Characteristic | No. (%) | P Valuea | ||
|---|---|---|---|---|
| Total Patients (N = 454) | Patients Without Ischemia (n = 312) | Patients With Ischemia (n = 142) | ||
| Demographics | ||||
| Age, mean (SD), y | 63 (9) | 63 (9) | 63 (9) | .48 |
| Men | 352 (77.5) | 238 (76.3) | 114 (80.3) | .34 |
| Black race | 114 (25.1) | 75 (24.0) | 39 (27.5) | .43 |
| Smoking history | 199 (43.8) | 141 (45.6) | 58 (40.8) | .60 |
| BMI, mean (SD) | 29.1 (5.1) | 29.2 (5.3) | 29.0 (5.1) | .81 |
| GFR, mean (SD) | 94.8 (31.4) | 94.4 (31.2) | 95.2 (32.4) | .71 |
| EF, mean (SD) | 53 (10) | 54 (10) | 52 (11) | .11 |
| Comorbidities | ||||
| History of hypertension | 332 (73.1) | 229 (73.4) | 103 (72.5) | .84 |
| History of diabetes | 124 (27.3) | 82 (26.3) | 42 (29.6) | .45 |
| CABG | 138 (30.4) | 84 (26.9) | 54 (38.0) | .02 |
| PCI | 251 (55.3) | 170 (54.5) | 81 (57.0) | .61 |
| MI | 169 (37.2) | 114 (36.5) | 55 (38.7) | .65 |
| History of heart failure | 66 (14.5) | 39 (12.5) | 27 (19.3) | .08 |
| Cerebrovascular disease | 28 (6.2) | 22 (7.1) | 6 (4.2) | .24 |
| Medications | ||||
| Aspirin | 406 (89.4) | 277 (88.8) | 129 (90.8) | .50 |
| ACEI/ARB | 208 (45.8) | 137 (43.9) | 71 (50.0) | .22 |
| β-Blocker | 317 (69.8) | 218 (69.9) | 99 (69.7) | .97 |
| Statin | 397 (87.4) | 267 (85.6) | 130 (91.5) | .10 |
| Stress test parameters | ||||
| Angina during stress test | 34 (8.2) | 12 (4.1) | 22 (17.6) | <.001 |
| Heart rate, mean (SD) | ||||
| At rest | 66.4 (12.2) | 65.7 (13.1) | 65.2 (10.7) | .71 |
| During exercise | 115 (14) | 116 (14) | 114 (12) | .09 |
| SBP, mean (SD) | ||||
| At rest | 135 (19) | 134 (18) | 133 (19) | .60 |
| During exercise | 161 (20) | 163 (19) | 160 (22) | .10 |
| RPP, mean (SD) | ||||
| At rest | 9051 (1921) | 9092 (1981) | 8901 (1911) | .77 |
| During exercise | 18 251 (4481) | 18 631 (4100) | 17 881 (4871) | .09 |
| Magnitude of ischemia | NA | NA | 7.1 (4.6) | |
| Hematocrit at rest, mean (SD) | 40.5 (4.4) | 40.3 (4.1) | 40.5 (4.2) | .60 |
| Hematocrit after exercise, mean (SD) | 41.3 (4.5) | 41.2 (4.2) | 41.7 (4.0) | .45 |
| CPC counts, median (IQR), cells/mL | ||||
| CD34+ | ||||
| At rest | 1642 (1034 to 2446) | 1647 (1054 to 2460) | 1590 (983 to 2430) | .81 |
| Absolute change from rest to stress | 10 (−378 to 362) | 53 (−274 to 523) | −172 (−619 to 266) | .003 |
| Percentage change from rest to stress | 0.6 (−21.0 to 27.3) | 6.1 (−12.3 to 40.6) | −10.2 (−28.1 to 5.5) | .006 |
| CD34+/CXCR4+ | ||||
| At rest | 654 (355 to 1051) | 650 (359 to 1049) | 659 (331 to 1032) | .76 |
| Change from rest to stress | −16 (−322 to 391) | 29 (−222 to 545) | −110 (−421 to 83) | .001 |
| Percentage change from rest to stress | −2.3 (−35.3 to 79.4) | 3.2 (−20.2 to 35.2) | −20.2 (−45.6 to 5.3) | <.001 |
Abbreviations: ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); CABG, coronary artery bypass graft; CPC, circulating progenitor cell; EF, ejection fraction; GFR, glomerular filtration rate; IQR, interquartile range; MI, myocardial infarction; NA, not applicable; PCI, percutaneous coronary intervention; RPP, rate pressure product; SBP, systolic blood pressure.
a
P value comparing patients with and without ischemia.