Exercise Stress MRI to Evaluate Aortic Function (Compliance, Distensibility, Pulse Wave Velocity) and Left Ventricular Function : Validation in Healthy Volunteers and in Selected Patients. A Pilot Study.
Detecting abnormalities in the left ventricular mechanical and hemodynamic response to the stress of exercise may offer early diagnostic indicators in patients suffering from valvular disease such as mitral regurgitation. Ultrasound-based imaging methods have been gaining importance in providing prognosis among those patients. However, decreased signal to noise ratio in the images and increased motion-related artifacts during exercise stress echocardiography have been reported, with a lack of reproducibility of results and a the limitation of its availability only in reference centers. In our laboratory, we are able to perform supine bicycle exercise MRI (1.5 T) using the Lode ergometer mounted on the far end of the patient table, previously described in healthy volunteers.
The first aim of our study is to demonstrate the safety and the feasibility of our MRI protocol in selected patients with asymptomatic severe organic mitral regurgitation, to assess left ventricular volumes and function, and regurgitant volume in comparison to exercise cardiac echography.
Besides, few recent studies sustain the relevance of novel markers of central aortic function (compliance, distensibility and pulse wave velocity) assessed by noninvasive MRI to explore vascular aging. In monogenic connective tissue diseases, altered arterial stiffness is the premature signature of the disease in asymptomatic patients. Noninvasive evaluation of aortic stiffness would be useful for risk assessment and preventive follow-up strategies in young asymptomatic relatives of subjects with aortic inherited diseases, such as syndromic and non-syndromic familial forms of thoracic aortic aneurysm and /or dissection. Furthermore, this technique should be able to evaluate the effect of drugs on aortic stiffness change in trials, before and after drug therapy, more relevant than the classic change in aortic diameter measurement.
The second aim of our study is 1) to provide the sensibility of our MRI protocol to estimate local and regional heterogeneity in aortic functional parameters (distensibility, compliance and PWV) 2) to evaluate the predictive value of these regional aortic parameters assessed by MRI to diagnose and to stratify the aortopathy related to presymptomatic Marfan patients and to bicuspid aortic valve in young adults, in comparison to carotids-femoral pulse wave velocity estimation by applanation tonometry.
|Study Design:||Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
|Official Title:||Exercise Stress MRI to Evaluate Aortic Function (Compliance, Distensibility, Pulse Wave Velocity) and Left Ventricular Function : Validation in Healthy Volunteers and in Selected Patients. A Pilot Study.|
- blood samples [ Time Frame: 24 MONTHS ] [ Designated as safety issue: No ]to estimate local and regional heterogeneity in aortic functional parameters
- aortic function [ Time Frame: 24 MONTHS ] [ Designated as safety issue: No ]MRI - magnetic resonance imaging
|Study Start Date:||December 2012|
|Estimated Study Completion Date:||July 2015|
|Estimated Primary Completion Date:||December 2014 (Final data collection date for primary outcome measure)|
|patients of an insufficiency organic severe surgical mitrale||Device: MRI Device: cardiac echography transthoracic|
|insufficiency organic mitrale moderated in severe asymptomatic||Device: MRI Device: cardiac echography transthoracic|
|patients of an aortic bicuspidie||Device: MRI Device: cardiac echography transthoracic|
|patients of a syndrome of Marfan||Device: MRI Device: cardiac echography transthoracic|
|Healthy volunteers||Device: MRI Device: cardiac echography transthoracic|
|Contact: jacquier firstname.lastname@example.org|
|Assistance Publique Hopitaux de Marseille||Not yet recruiting|
|Marseille, France, 13354|
|Contact: bernard belaigues 0491382747 email@example.com|
|Principal Investigator: alexis jacquier|
|Study Director:||BERNARD BELAIGUES||Assistance Publique Hopitaux De Marseille|
|Principal Investigator:||alexis jacquier||AP HM|