Table 1.
Descriptive statistics for the three trials
| AJAX (n = 116) | ECAR (n = 107) | IMPROVE (n = 613) | |
|---|---|---|---|
| Randomized group | |||
| EVAR/EVAR strategy | 57 (49·1) | 56 (52·3) | 316 (51·5) |
| Open repair | 59 (50·9) | 51 (47·7) | 297 (48·5) |
| rAAA suitable for EVAR‡ | n = 113 | n = 104 | n = 310 |
| EVAR/EVAR strategy | 57 (50·4) | 54 (51·9) | 168 (54·2) |
| Open repair | 56 (49·6) | 50 (48·1) | 142 (45·8) |
| Procedure commenced | |||
| EVAR | 57 (49·1) | 56 (52·3) | 192 (31·3) |
| Open repair | 59 (50·9) | 50 (46·7) | 331 (54·0) |
| No aneurysm repair | 0 (0) | 1 (0·9) | 90 (14·7) |
| Age (years)* | 74·2(9·4) | 74·4(10·6) | 76·7(7·6) |
| Sex ratio (M : F) | 99 : 17 | 97 : 10 | 480 : 133 |
| Admission mean arterial BP (mmHg)*, § | n = 113 | n = 104 | n = 601 |
| 87(27) | 108(30) | 81(24) | |
| Hardman index | n = 61 | n = 105 | n = 539 |
| 0 | 26 (43) | 41 (39·0) | 164 (30·4) |
| 1 | 19 (31) | 44 (41·9) | 254 (47·1) |
| 2 | 12 (20) | 11 (10·5) | 94 (17·4) |
| ≥ 3 | 4 (7) | 9 (8·6) | 27 (5·0) |
| Morphology | |||
| Maximum aortic diameter (mm)* |
n = 92 76(16) |
n = 106 77(20) |
n = 518 84(19) |
| Aneurysm neck diameter (mm)*, ¶ |
n = 92 26(4) |
n = 106 24(4) |
n = 430 26(4) |
| Neck length (mm)† |
n = 92 25 (19–34) |
n = 101 21 (15–30) |
n = 481 22 (10–34) |
| Proximal neck angle (°)* |
n = 92 39(21) |
n = 96 34(26) |
n = 478 33(20) |
Values in parentheses are percentages unless indicated otherwise;
*
values are mean(s.d.) and
†
median (i.q.r.).
‡
Suitability for endovascular aneurysm repair (EVAR) in IMPROVE defined by local assessment of suitability if available; otherwise a core laboratory assessment of ‘within liberal instructions for use’ was used to define suitability. Suitability not assessed in 46 ruptured abdominal aortic aneurysms (rAAAs) in IMPROVE and one in ECAR.
§
Mean arterial BP recorded only in ECAR; for AJAX and IMPROVE it was approximated by 2/3 diastolic + 1/3 systolic BP.
¶
IMPROVE and ECAR measured top neck diameter; AJAX measured maximum neck diameter.