Table IV. Semiquantitative histomorphology19.
| Characteristic | Sham | Matrix | PAE/matrix |
|---|---|---|---|
| Intimal fibrin | 0.06 ± 0.04 | 0.0 ± 0.0 | 0.0 ± 0.0 |
| Endothelializationa | 4.0 ± 0.0 | 4.0 ± 0.0 | 4.0 ± 0.0 |
| Adventitial fibrosis | 1.0 ± 0.32 | 0.33 ± 0.27 | 0.72 ± 0.16 |
| Neointimal hypocellularityb | 1.33 ± 0.12 | 1.1 ± 0.22 | 0.44 ± 0.14c |
| Medial smooth muscle cell necrosis | 0.28 ± 0.13 | 0.0 ± 0.0 | 0.06 ± 0.06 |
| Adventitial vascularization | 0.0 ± 0.0 | 0.0 ± 0.0 | 0.0 ± 0.0 |
| Inflammationd | 0.61 ± 0.04 | 0.53 ± 0.09 | 0.60 ± 0.16 |
| Injury scoree | 0.04 ± 0.04 | 0.0 ± 0.0 | 0.1 ± 0.04 |
PAE, Porcine aortic endothelial cells.
a
Endothelialization was scored on a scale from 0 to 4 (0 = absent; 1 < 25%; 2 = 25-75%; 3> 75%; 4 = 100%) and depended upon the extent of the circumference of the artery lumen showing coverage with endothelial cells.
b
Characterized by areas of neointima with increased interstitial matrix within/around smooth muscle cells.
c
P < .05 compared with control arteries.
d
Sum of strut inflammation scores/No. of stent struts.
e
The injury score depended on the part of the arterial wall perturbed by the stent. Injury was scored from 0 to 3 on a per-strut basis and the average was calculated per plane (0 = IEL intact; 1 = IEL disrupted; 2 = tunica media disrupted; 3 = tunica adventitia disrupted).