Comparison of Aliskiren vs Negative Controls on Aortic Stiffness in Patients With MFS
Status:
Completed
Trial end date:
2014-12-01
Target enrollment:
Participant gender:
Summary
Marfan syndrome (MFS) is an inherited disorder of connective tissue with morbidity and
mortality from aortic dilatation and dissection. The current standard of care is beta-blocker
(BB) treatment and therapeutic target is heart rate. The degree of aortic dilatation and
response to BB vary in adults with MFS. However, aortic stiffness is often present, and can
be a predictor of aortic dilatation and cardiovascular complications. Aortic stiffness is a
logical therapeutic target in adults with MFS.
Transforming growth factor beta(TGF-beta) mediates disease pathogenesis in MFS and
contributes to aortic stiffness. Cross-talk between TGF-beta system and renin-angiotensin
system (RAS) has been demonstrated. The angiotensin receptor blocker (ARB), losartan,
inhibits TGF-beta activity and reverses aortic wall pathology in a Marfan mouse model. In a
small cohort study, the use of ARB therapy (losartan or irbesartan) significantly slowed the
rate of progressive aortic dilatation in patients with MFS, after BB therapy had failed to
prevent aortic root dilatation. In another study, angiotensin converting enzyme inhibitor,
perindopril, reduced both aortic stiffness and aortic root diameter in patients with MFS
taking standard BB therapy. Renin inhibitor, aliskiren, has not been studied to reduce aortic
stiffness and attenuate aortic dilatation in patients with MFS.
This trial is a randomized, open-label trial of 32 patients with Marfan syndrome, treated
with 6 months of aliskiren vs. negative controls in patients with MFS under atenolol
treatment. MRI for aortic pulsed wave velocity (PWV) and distensibility, measurements of
central BP (CBP) and augmentation index (AIx) will be performed at the beginning and end of
treatment. A blood drawn for serum markers of TGF-beta, extracellular matrix turnover and
inflammation will also be performed at 0 and 6 months. We plan to determine whether aliskiren
decreases aortic stiffness significantly more than negative controls in patients with MFS
under atenolol treatment.