Arterial wall strength after endovascular photodynamic therapy.
OBJECTIVE
Vascular photodynamic therapy (PDT) inhibits intimal hyperplasia (IH) induced by angioplasty in rat iliac arteries by eradicating the proliferating smooth muscle cells. This process may jeopardise the structure and strength of the arterial wall, reflected by a decreased bursting pressure.


METHODS
Thirty male Wistar rats of 250-300 g were subdivided into 3 groups (n = 10). In all groups, IH was induced by balloon injury (BI). One experimental group received PDT at 50 J/cm diffuser length, the other group at 100 J/cm diffuser length. The third group served as control group and received no PDT. In half of each group the bursting pressure was analyzed after 2 hours (n = 5), in the other half after 1 year.


RESULTS
Two hours after the procedure the bursting pressure was 3.37 +/- 0.58 (+/-SEM) bar in the BI + PDT 50 and 3.96 +/- 0.43 bar in the BI + PDT 100 group, compared to 2.20 +/- 0.27 bar in the BI group (P < 0.05). After 1 year these values were 3.18 +/- 0.87 bar in the BI + PDT 50 (P < 0.05) and 2.02 +/- 0.31 bar in the BI + PDT 100 group, compared to 2.10 +/- 0.30 bar in the BI group (NS). In the BI + PDT 100 group, 3 out of 5 rats appeared to have aneurysmal dilatation after 1 year.


CONCLUSIONS
Endovascular PDT increases the arterial wall strength as measured by the bursting pressure at short-term. After 1 year, wall strength is not diminished as measured by bursting pressure, but aneurysmal dilatation nevertheless developed with 100 J/cm. dl. This may limit the use of high energy PDT.
Gabeler
Edward E E
EE
Department of Surgery, Erasmus MC, Rotterdam, The Netherlands. EEEGabeler@hotmail.com
van Hillegersberg
Richard
R
Sluiter
Wim
W
Kliffen
Mike
M
Statius van Eps
Randolph G
RG
Honkoop
Jan
J
Carlier
Stephane G
SG
van Urk
Hero
H
D000622:Aminolevulinic Acid / Q000627:therapeutic use*; D000800:Angioplasty, Balloon / Q000009:adverse effects; D000818:Animals; D004195:Disease Models, Animal; D006965:Hyperplasia / Q000209:etiology / Q000517:prevention & control; D007083:Iliac Artery / Q000187:drug effects / Q000528:radiation effects* / Q000601:surgery; D008297:Male; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D013718:Tensile Strength / Q000187:drug effects / Q000528:radiation effects*; D017539:Tunica Intima / Q000187:drug effects / Q000528:radiation effects* / Q000601:surgery
D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid