Comparison of Aliskiren vs Negative Controls on Aortic Stiffness in Patients With MFS
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.
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Open LabelPrimary Purpose: Treatment
|Official Title:||Comparison Study of the Effect of Aliskiren Versus Negative Controls on Aortic Stiffness in Patients With Marfan Syndrome Under Treatment With Atenolol|
- Central Aortic Distensibility by MRI [ Time Frame: 6 months ]Analyses of the MRIs were performed using commercial software (Argus version 4.02, Siemens Medical Systems, Germany) by experienced observers who were blinded to patient information. To measure central aortic distensibility, the systolic and diastolic cross-sectional areas were measured by manual contouring of the aorta through the cardiac cycle on the cine image. Distensibility at the four regions was calculated as the mean of values obtained from the following equation: Distensibility = (Amax - Amin)/[Amin × (Pmax - Pmin)](10-3mm/Hg), where Amax is the maximal (systolic) aortic area, Amin is the minimal (diastolic) aortic area, Pmax is the systolic blood pressure (SBP), and Pmin is the diastolic blood pressure (DBP). Central aortic blood pressure measured non-invasively by SphygmoCor was used for systolic and diastolic blood pressure.
- Central Aortic PWV(Pulsed Wave Velocity) [ Time Frame: 6 months ]Aortic PWV was measured according to the well-validated method using MRI 19. From the velocity-encoded MRIs, aortic contours were automatically detected and manually adjusted in each slice area throughout the cardiac cycle. The transit time between the flow curves of each region of the aorta was determined from the midpoint of the systolic up-slope on the flow versus time curve 26-28. The up-slopes were identified by drawing a line between the points of 40% and 60% maximum velocity on the waveform. The distance between each aortic level was measured on black blood images using a curved line along the center of the aorta. Based on these data, the regional PWV was calculated as the ratio of the distance between levels and the time differences between the arrival of the pulse wave at each level. The PWV was measured at two regions: the proximal aorta (proximal PWV between level 1 and level 2) and the entire aorta (PWV-total between level 1 and level 4).
|Study Start Date:||June 2010|
|Study Completion Date:||December 2014|
|Primary Completion Date:||October 2014 (Final data collection date for primary outcome measure)|
Experimental: Atenolol & Aliskiren
Atenolol tablet and Aliskiren 150mg or 300mg tablet by mouth per day for 6month
Other Name: RasilezDrug: Atenolol
Other Name: Tenormin
Atenolol tablet(Negative controls, Open-label)
Other Name: Tenormin
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Please refer to this study by its ClinicalTrials.gov identifier: NCT01715207
|Korea, Republic of|
|Samsung Medical Center|
|Seoul, Korea, Republic of, 135-710|
|Principal Investigator:||Duk-Kyung Kim, PhD MD||Samsung Medical Center|