3010, oral, cat. 58
RECENT ADVANCES IN THE TREATMENT OF ABDOMINAL AORTIC
ANEURYSM: ROLE OF PHOTOTHERAPY
S.D. Gertz1, C. Rubinstein2, A. Bulut2, Y. Berlatzky2, R. Beeri2, D. Gilon2,
L. Gavish1, M. Harlev1, P. Reissman3, L. Gavish1
1
Institute for Medical Research-IMRIC, Hadassah Faculty of Medicine, The Hebrew
University, 2Hadassah University Hospital, 3Shaarei Zedek Hospital, Jerusalem, Israel
Acute treatment of abdominal aortic aneurysm (AAA) is based primarily on open
abdomen anastamosis of an interposition graft or endovascular exclusion with
membrane covered stents. The complications associated with these procedures, and
the increased detection of AAA in early stages of development, have emphasized the
need for therapeutic strategies that target mechanisms of progression and rupture.
Pharmacological therapy for small aneurysms using antihypertensives or agents such
as doxycycline have been of limited efficacy. Studies by our group have suggested
that phototherapy may be a modality of great promise for retardation of the
progression of AAA in early stages of development. We found that low level laser
irradiation (LLLI) (780 nm) increases aortic smooth muscle cell proliferation and
matrix protein secretion, and inhibits gene expression and secretion of inflammatory
cytokines from activated monocytes in vitro. Using high frequency ultrasound (HFU/S, 0.01mm resolution) with correlative histomorphometric analysis, we showed that
perivascular LLLI inhibits AAA progression in vivo in angiotensin-II infused,
apolipoprotein E-deficient (apo E-/-) mice. We found that the origin of the mural
dissection and aneurysm formation in this model showed a distinct predilection for
branch points. Enhanced fibrous tissue repair and reduction of medial inflammatory
cells appear to be major mechanisms subtending the inhibitory effect of LLLI on
aneurysm progression in this model. Studies in large animals involving the delivery of
LLLI, either endovascularly or perivascularly by laparoscopy, would appear to be the
next appropriate steps toward testing the applicability of this technology to the human
interventional setting.