Table 1.
Baseline Clinical and Angiographic Characteristics of All-Comers
| Characteristics | Randomly Assigned Groups |
Registry∗ (N = 310) |
|
|---|---|---|---|
| Immediate Stenting (n = 49) |
Deferred Stenting (n = 52) |
||
| Clinical | |||
| Age, yrs | 61.7 ± 12.2 | 57.6 ± 10.9 | 61.4 ± 12.9 |
| Male | 36 (73.5) | 34 (65.4) | 196 (63.2) |
| Heart rate, beats/min | 83 ± 17 | 77 ± 17 | 83 ± 32 |
| Systolic blood pressure, mm Hg | 138 ± 27 | 141 ± 24 | 131 ± 28∗ |
| Diastolic blood pressure, mm Hg | 79 ± 17 | 83 ± 11 | 77 ± 16∗ |
| Diabetes mellitus,† | 6 (12.2) | 7 (13.5) | 30 (9.7) |
| Previous MI | 2 (4.1) | 5 (9.6) | 30 (9.7) |
| Previous PCI | 2 (4.1) | 2 (3.8) | 21 (6.8) |
| Heart failure, Killip class at presentation† | |||
| I | 35 (71.4) | 38 (73.1) | — |
| II | 13 (26.6) | 12 (23.1) | — |
| III | 1 (2.0) | 2 (3.8) | — |
| Procedure | |||
| Time from symptom onset to reperfusion (first balloon or aspiration thrombectomy), min | 183 (131–337) | 166 (124–276) | 184 (124–338) |
| Time from symptom onset to reperfusion >12 h | 5 (10.2) | 1 (1.9) | 6 (5.9) |
| Coronary angiography | |||
| No. of diseased arteries | |||
| 1 | 26 (55.3) | 22 (45.8) | — |
| 2 | 15 (31.9) | 17 (35.4) | — |
| 3 | 6 (12.8) | 9 (18.8) | — |
| Culprit artery | |||
| LAD | 18 (36.7) | 15 (28.8) | 131 (42.3)∗ |
| LCX | 6 (12.2) | 11 (21.2) | 42 (13.5)∗ |
| RCA | 25 (51.1) | 25 (48.1) | 132 (42.6) |
| Vein graft | 0 (0.0) | 1 (1.9) | 2 (0.6) |
| Left main | 0 (0.0) | 0 (0.0) | 3 (1.0) |
| TIMI coronary flow grade pre-PCI‡ | |||
| 0/1 | 39 (79.6) | 40 (76.9) | 200 (64.5)∗ |
| 2 | 7 (14.3) | 6 (11.5) | 43 (13.9) |
| 3 | 3 (6.1) | 6 (11.5) | 67 (21.6)∗ |
| Lesion length, mm∗ | 15.4 (11.2–20.6) | 13.5 (11.2–17.8) | — |
| Coronary artery diameter at the start of the procedure, mm∗ | |||
| Proximal to the culprit lesion | 3.2 ± 0.7 | 3.2 ± 0.6 | — |
| Distal to the culprit lesion | 2.7 ± 0.6 | 2.7 ± 0.6 | — |
| Thrombus present,∗ | 47 (95.9) | 51 (98.1) | 284 (91.6) |
| Thrombus area, mm2∗ | 13.0 (8.3–20.2) | 19.9 (12.0–1.3) | — |
| TIMI thrombus grade | |||
| 0/1 | 21 (42.9) | 22 (42.3) | 151 (48.9) |
| 2 | 6 (12.2) | 6 (11.5) | 62 (20.1) |
| 3 | 10 (20.4) | 7 (13.5) | 60 (19.4) |
| 4 | 12 (24.5) | 17 (32.7) | 36 (11.7) |
| Jeopardized myocardium by the ECG Aldrich score (% left ventricle)§(14) | 20 (17–30) | 19 (15–26) | — |
| Procedure details | |||
| Aspiration thrombectomy | 42 (85.7) | 46 (88.5) | — |
| Glycoprotein IIb/IIIa inhibitor therapy | 46 (98.9) | 51 (98.1) | — |
| Pre-dilation | 36 (73.5) | 46 (88.5) | — |
| Post-dilation | 35 (71.4) | 30 (57.7) | — |
| Final inflation pressure, kPa | 17.4 ± 2.4 | 16.4 ± 3.2 | — |
| Intracoronary adenosine therapy | 4 (8.2) | 3 (5.8) | — |
| No. of stents | |||
| 0 | 0 | 3 (5.8) | — |
| 1 | 39 (79.6) | 33 (63.5) | — |
| 2 | 9 (18.4) | 16 (30.8) | — |
| 3 | 1 (2.0) | 0 | — |
| Contrast volume, ml | 205 (172–250) | 278 (238–312) | — |
Values shown are n (%), mean ± SD, median (interquartile range) .
ECG = electrocardiogram; LAD = left anterior descending artery; LCA = left circumflex artery; MI = myocardial infarction; PCI = percutaneous coronary intervention; TIMI = Thrombolysis In Myocardial Infarction grade.
The following clinical characteristics differed between the registry patients and the randomly assigned patients who were enrolled in the trial: systolic blood pressure (p = 0.003), diastolic blood pressure (p = 0.022), TIMI thrombus grade 4 (p < 0.0001), and TIMI flow grade pre-PCI (TIMI flow grade 0/1, p = 0.015; TIMI flow grade 3, p = 0.007). Quantitative coronary and electrocardiographic analyses were done in the randomized patients but not in the registry patients.
Diabetes mellitus was defined as a history of diet-controlled or treated diabetes. Killip classification of heart failure after acute myocardial infarction: class I, no heart failure; class II, pulmonary rales or crepitations, a third heart sound, and increased jugular venous pressure; class III, acute pulmonary edema; class IV, cardiogenic shock. A diseased artery was defined as an epicardial artery (≥2 mm) with ≥1 lesions ≥50% of the reference vessel diameter.
TIMI coronary flow grade pre-PCI was not assessable in 1 patient in the immediate stenting group. Intracoronary adenosine (10 to 30 μg) was administered as bolus therapy during primary PCI as clinically indicated for reduced coronary flow. The clinical and treatment characteristics of the patients included in the immediate stenting group and the deferred stenting group were similar except for the total volume of contrast, which was greater in the deferred stenting group (p < 0.0001). Procedure details and outcomes include the first and second procedures in the deferred stenting group. Two deferred stenting patients experienced culprit artery reocclusion before the planned second procedure. The coronary flow grades at the end of the first procedure and at the start of the second procedure differed in 3 other deferred stenting patients as follows: 2 patients changed from TIMI flow grade 3 to 2, and 1 patient changed from TIMI flow grade 2 to 3. None of the patients received bail-out or covered stents.
ST-segment elevation was measured on the baseline ECG before reperfusion to estimate the extent of initial myocardial jeopardy with the Aldrich ST-segment elevation score (14).