Table 1 Characteristics of CIAKI and non-CIAKI patients in the three groups
Characteristics | Training set (n = 2368) | Internal validation set (n = 592) | External validation set (n = 554) | ||||||
|---|---|---|---|---|---|---|---|---|---|
Non-CIAKI | CIAKI | P | Non-CIAKI | CIAKI | P | Non-CIAKI | CIAKI | P | |
Demographics | |||||||||
 Age, yrs | 65.97 ± 10.10 | 68.22 ± 10.55 |  < 0.001 | 65.27 ± 10.25 | 68.06 ± 10.59 | 0.012 | 63.59 ± 10.95 | 70.65 ± 8.85 |  < 0.001 |
 Female, n(%) | 602 (31.3) | 146 (32.7) | 0.587 | 165 (34) | 38 (35.5) | 0.768 | 180 (38.0) | 39 (48.8) | 0.068 |
 Height, cm | 166.63 ± 7.70 | 165.99 ± 7.27 | 0.11 | 166.12 ± 7.73 | 166.00 ± 7.58 | 0.881 | 166.98 ± 7.73 | 164.34 ± 7.65 | 0.005 |
 Weight, kg | 70.46 ± 10.54 | 69.72 ± 10.74 | 0.183 | 70.07 ± 11.72 | 69.8 ± 11.78 | 0.828 | 70.62 ± 10.44 | 66.93 ± 9.01 | 0.003 |
 BMI, kg/m2 | 25.31 ± 2.94 | 25.25 ± 3.23 | 0.693 | 25.33 ± 3.51 | 25.25 ± 3.42 | 0.838 | 25.14 ± 2.95 | 24.62 ± 2.87 | 0.146 |
Medical history | |||||||||
 Hypertension, n(%) | 1467 (76.4%) | 362 (81) | 0.036 | 362 (74.6) | 82 (76.6) | 0.666 | 315 (66.5) | 54 (67.5) | 0.855 |
NYHA Classification, n(%) |  |  |  < 0.001 |  |  |  < 0.001 |  |  |  < 0.001 |
 NYHA Classification I | 108 (7.8) | 17 (6.3) |  | 37 (10.7) | 2 (3.1) |  | 149 (45.3) | 10 (18.9) |  |
 NYHA Classification II | 1046 (75.7) | 142 (52.6) |  | 250 (72.3) | 37 (57.8) |  | 134 (40.7) | 22 (41.5) |  |
 NYHA Classification III | 201 (14.6) | 94 (34.8) |  | 49 (14.2) | 19 (29.7) |  | 38 (11.6) | 17 (32.1) |  |
 NYHA Classification IV | 26 (1.9) | 17 (6.3) |  | 10 (2.9) | 6 (9.4) |  | 8 (2.4) | 4 (7.5) |  |
 CHF, n(%) | 187 (10.1) | 97 (22.1) |  < 0.001 | 49 (10.5) | 22 (21.4) | 0.003 | 48 (10.4) | 20 (25.0) |  < 0.001 |
 Prior myocardial infarction, n(%) | 200 (10.4) | 46 (10.3) | 0.94 | 34 (7.0) | 9 (8.4) | 0.613 | 30 (6.3) | 7 (8.8) | 0.422 |
 Stable Angina, n(%) | 221 (11.5) | 31 (6.9) | 0.005 | 48 (9.9) | 4 (3.7) | 0.042 | 23 (4.9) | 9 (11.3) | 0.023 |
 ACS, n(%) | 813 (42.3) | 346 (77.4) |  < 0.001 | 198 (40.8) | 82 (76.6) |  < 0.001 | 383 (80.8) | 70 (87.5) | 0.151 |
Diabetes history, yrs | Â | Â | 0.125 | Â | Â | 0.931 | Â | Â | 0.072 |
  < 1 | 75 (4.5) | 13 (3.1) |  | 22 (5.2) | 5 (5.2) |  | 49 (10.5) | 6 (7.9) |  |
 1–5 | 297 (17.8) | 64 (15.5) |  | 65 (15.3) | 5 (12.4) |  | 144 (30.8) | 20 (26.3) |  |
 5–10 | 462 (27.7) | 110 (26.6) |  | 142 (33.4) | 31 (32.0) |  | 102 (21.8) | 12 (15.8) |  |
 10–20 | 649 (39.0) | 164 (39.7) |  | 146 (34.4) | 37 (38.1) |  | 124 (26.6) | 22 (28.9) |  |
  >  = 20 | 183 (11.0) | 62 (15.0) |  | 50 (11.8) | 12 (12.4) |  | 48 (10.3) | 16 (21.1) |  |
 CKD, n(%) | 211 (11.5) | 115 (25.7) |  < 0.001 | 57 (11.8) | 26 (24.3) | 0.001 | 32 (6.8) | 24 (30.0) |  < 0.001 |
 Anemia, n(%) | 575 (29.9) | 202 (45.2) |  < 0.001 | 143 (29.5) | 48 (44.9) | 0.002 | 81 (17.1) | 25 (31.3) | 0.003 |
CAG and PCI | |||||||||
Vessels of coronary artery disease, n(%) | Â | Â | 0.039 | Â | Â | 0.004 | Â | Â | 0.003 |
 0 | 224 (11.7) | 42 (9.4) |  | 59 (12.2) | 9 (8.4) |  | 23 (4.9) | 0 (0) |  |
 1 | 617 (32.1) | 124 (27.7) |  | 160 (33.0) | 36 (33.6) |  | 75 (15.8) | 9 (11.3) |  |
 2 | 735 (38.3) | 176 (39.4) |  | 187 (38.6) | 38 (35.5) |  | 142 (30.0) | 16 (20.0) |  |
 3 | 281 (14.6) | 79 (17.7) |  | 64 (13.2) | 12 (11.2) |  | 190 (40.1) | 38 (47.5) |  |
 4 | 54 (2.8) | 20 (4.5) |  | 14 (2.9) | 9 (8.4) |  | 37 (7.8) | 13 (16.3) |  |
 5 | 9 (0.5) | 5 (1.1) |  | 1 (0.2) | 3 (2.8) |  | 7 (1.5) | 4 (5) |  |
 6 | 1 (0.1) | 1 (0.2) |  | 0 (0) | 0 (0) |  | 0 (0) | 0 (0) |  |
 Single-vessel disease, n(%) | 617 (32.1) | 124 (27.7) | 0.072 | 160 (33) | 36 (33.6) | 0.896 | 75 (15.8) | 9 (11.3) | 0.292 |
 Multi-vessel disease, n(%) | 1080 (56.2) | 281 (62.9) | 0.011 | 266 (54.8) | 62 (57.9) | 0.559 | 376 (79.3) | 71 (88.8) | 0.048 |
 Preoperative SBP, mmHg | 134.11 ± 16.68 | 136.15 ± 20.61 | 0.051 | 133.94 ± 17.30 | 136.48 ± 19.95 | 0.183 | 136.35 ± 18.09 | 139.03 ± 21.38 | 0.235 |
 Preoperative DBP, mmHg | 78.73 ± 10.96 | 80.76 ± 12.83 | 0.002 | 78.72 ± 11.23 | 79.30 ± 13.44 | 0.641 | 79.21 ± 11.58 | 80.30 ± 12.85 | 0.444 |
Contrast agent | |||||||||
 Nonionic low-osmolar, n(%) | 712 (37.1) | 116 (26.0) |  < 0.001 | 178 (36.7) | 32 (29.9) | 0.184 | 306 (64.6) | 58 (72.5) | 0.166 |
 Nonionic iso-osmolar, n(%) | 1168 (60.8) | 320 (71.6) |  < 0.001 | 292 (62.2) | 71 (66.4) | 0.237 | 185 (39.0) | 24 (30.0) | 0.123 |
 Volume of contrast agent, mL | 191.22 ± 68.78 | 203.65 ± 69.51 | 0.001 | 187.90 ± 66.72 | 204.91 ± 71.22 | 0.019 | 162.10 ± 90.49 | 167.96 ± 75.90 | 0.584 |
Medications | |||||||||
 Β-blocker, n(%) | 1179 (31.3) | 248 (55.5) | 0.022 | 292 (60.2) | 59 (55.1) | 0.334 | 325 (68.6) | 34 (42.5) |  < 0.001 |
 ACEI/ARB, n(%) | 1105 (57.5) | 288 (64.4) | 0.008 | 284 (58.6) | 70 (65.4) | 0.19 | 305 (64.3) | 55 (68.8) | 0.445 |
 Diuretics, n(%) | 334 (17.9) | 174 (39.5) |  < 0.001 | 85 (18.1) | 41 (38.3) |  < 0.001 | 205 (43.2) | 46 (57.5) | 0.018 |
 CCB, n(%) | 531 (28.3) | 107 (24.5) | 0.111 | 129 (27.3) | 25 (23.8) | 0.461 | 178 (37.6) | 31 (38.8) | 0.838 |
 Insulins, n(%) | 952 (49.6) | 259 (57.9) | 0.001 | 227 (46.8) | 60 (56.1) | 0.082 | 148 (31.2) | 31 (38.8) | 0.183 |
 Oral hypoglycemic agent, n(%) | 1125 (58.6) | 237 (53.0) | 0.033 | 261 (53.8) | 48 (44.9) | 0.093 | 346 (73.0) | 55 (68.8) | 0.432 |
Pre-procedural laboratory determinations | |||||||||
 Glucose, mmol/L | 9.25 ± 3.69 | 9.82 ± 3.80 | 0.004 | 9.37 ± 3.61 | 9.75 ± 3.08 | 0.318 | 9.17 ± 3.72 | 8.16 ± 1.80 |  < 0.001 |
 BUN, mg/dL | 6.31 ± 2.16 | 7.26 ± 3.62 |  < 0.001 | 6.26 ± 2.36 | 7.28 ± 3.37 | 0.004 | 5.99 ± 2.30 | 7.23 ± 2.73 |  < 0.001 |
 Baseline creatinine, umol/L | 76.12 ± 27.99 | 88.71 ± 42.36 |  < 0.001 | 76.63 ± 29.76 | 88.59 ± 42.32 | 0.006 | 67.42 ± 22.50 | 88.97 ± 40.08 |  < 0.001 |
 eGFR, mL/min/1.73 m2 | 85.80 ± 19.53 | 76.81 ± 24.69 |  < 0.001 | 85.50 ± 20.22 | 76.98 ± 25.39 | 0.001 | 95.77 ± 22.50 | 78.82 ± 16.23 |  < 0.001 |
CKD stage, n(%) |  |  |  < 0.001 |  |  | 0.002 |  |  |  < 0.001 |
 Stage 1 | 976 (50.8) | 160 (35.8) |  | 240 (49.5) | 40 (37.4) |  | 314 (66.2) | 19 (23.8) |  |
 Stage 2 | 724 (37.7) | 171 (38.3) |  | 188 (38.8) | 41 (38.3) |  | 128 (27.0) | 37 (46.3) |  |
 Stage 3 | 207 (10.8) | 107 (23.9) |  | 56 (11.5) | 24 (22.4) |  | 30 (6.3) | 19 (23.8) |  |
 Stage 4 | 14 (0.7) | 9 (2.0) |  | 1 (0.2) | 2 (1.9) |  | 2 (0.4) | 5 (6.3) |  |
 Hemoglobin, g/L | 133.05 ± 15.77 | 127.98 ± 19.87 |  < 0.001 | 132.68 ± 15.99 | 127.41 ± 19.49 | 0.01 | 135.35 ± 16.30 | 125.78 ± 20.55 |  < 0.001 |
 Albumin, g/L | 38.87 ± 3.80 | 37.63 ± 4.30 |  < 0.001 | 38.79 ± 3.70 | 38.13 ± 3.76 | 0.097 | 42.34 ± 4.24 | 39.27 ± 4.49 |  < 0.001 |
 Uric acid, umol/L | 326.18 ± 102.42 | 373.06 ± 133.01 |  < 0.001 | 330.11 ± 108.48 | 391.19 ± 125.08 |  < 0.001 | 314.63 ± 95.32 | 372.58 ± 105.38 |  < 0.001 |
 Total cholesterol, mmol/L | 3.83 ± 1.13 | 3.99 ± 1.18 | 0.01 | 3.83 ± 1.08 | 4.24 ± 1.13 |  < 0.001 | 4.28 ± 1.18 | 3.96 ± 0.88 | 0.005 |
 Triglycerides, mmol/L | 1.75 ± 1.38 | 1.72 ± 1.26 | 0.604 | 1.79 ± 1.19 | 1.90 ± 1.39 | 0.413 | 2.08 ± 1.7 | 1.75 ± 1.05 | 0.019 |
 HDL, mmol/L | 0.98 ± 0.23 | 0.98 ± 0.26 | 0.946 | 0.98 ± 0.23 | 1.03 ± 0.27 | 0.091 | 1.11 ± 0.31 | 1.12 ± 0.26 | 0.861 |
 LDL, mmol/L | 2.23 ± 0.90 | 2.37 ± 0.97 | 0.004 | 2.21 ± 0.89 | 2.46 ± 0.91 | 0.01 | 2.46 ± 0.94 | 2.33 ± 0.83 | 0.254 |
Urine protein level, n(%) |  |  |  < 0.001 |  |  |  < 0.001 |  |  |  < 0.001 |
 0 | 1722 (89.6) | 353 (79) |  | 439 (90.5) | 81 (75.7) |  | 390 (82.3) | 14 (17.5) |  |
 1 | 122 (6.4) | 55 (12.3) |  | 32 (6.6) | 18 (16.8) |  | 65 (13.7) | 27 (33.8) |  |
 2 | 52 (2.7) | 31 (6.9) |  | 11 (2.3) | 5 (4.7) |  | 17 (3.6) | 28 (35.0) |  |
 3 | 25 (1.3) | 8 (1.8) |  | 3 (0.6) | 3 (2.8) |  | 2 (0.4) | 11 (13.8) |  |
 Proteinuria, n(%) | 199 (10.4) | 94 (21.0) |  < 0.001 | 46 (9.5) | 26 (24.3) |  < 0.001 | 77 (16.2) | 64 (80.0) |  < 0.001 |
 LVEF, % | 59.48 ± 9.59 | 55.00 ± 11.82 |  < 0.001 | 59.64 ± 9.38 | 54.43 ± 11.88 |  < 0.001 | 57.10 ± 7.64 | 51.84 ± 10.25 |  < 0.001 |