Impact of Afterload Reduction in Left Ventricular Function in Patients with Aortic Stenosis - Can We Assess Contractility?
Aortic stenosis (AS) is the most frequent heart valve disease in the western world. The prevalence in Denmark varies from 2 to 7%, increasing with age. With the increasing elderly population, it is very likely that the prevalence will increase even further in the following years. A major part of AS patients develops permanent damage to the cardiac muscle before they experience symptoms.
Approximately 1.600 Danes undergo operation for heart valve diseases, the vast majority because of aortic stenosis. AS is a slow degenerative of the aortic valve cuspids caused by gradual accumulation of calcium. This accumulation creates a narrowing, which in time reduces the area of the valve causing obstruction in the left ventricle (LV). The obstruction causes the pressure in the LV to rise and in turn, the cardiac muscle is damaged and scar tissue is formed.
The treatment of AS has for the most part been reserved for the relatively young, fit and healthy. However, in 2007 a new minimally invasive procedure was introduced, the transfemoral aortic valve replacement. It is now possible to replace the stenotic heart valve by inserting a catheter through the femoral artery ascending through the aorta until the aortic valve is reached. By inserting a guidewire which the valve deployment system can be guided to the heart, it is possible to push the degenerative and calcified valve to the side so a new valve can take its place.
Transfemoral aortic valve replacement is an alternative to open heart surgery in patients, who are at intermediate to high risk or too fragile to undergo general anesthesia and open surgery. However, both procedures have something in common, treatment is prolonged until the patient experience symptoms, shortness of breath, presyncope and syncopation.
In the period between detecting a narrow heart valve and experiencing symptoms, 1 % of patients suddenly die and a large fraction of patients suffer permanent damage to the heart. The damage of the heart can be so pronounced that 1/3 patients undergoing valve replacement wont benefit from the procedure.
New methods have been suggested to help doctors identify the patient, who have suffered damage to the heart and even find patients, who might benefit from early intervention.
Our ambition is to shed light on this matter and contribute to a solution. In the last years two image-based calculations have been suggested, end-systolic wall stress corrected left ventricular ejection fraction and first-phase ejection fraction. The calculations are based upon echocardiography and CT-scans. Patients will undergo both before and after the placement of the new heart valve. We hope that our findings can contribute to a solution in the future.
Description of the cohort
The cohort consists of men and women who are eligible for transfemoral aortic valve replacement. To be considered eligible one must have aortic valve stenosis defined as:
1. Aortic valve area < 1 cm2 AND
2. Transvalvular maximum velocity of > 3.5 m/s AND
3. aortic stenosis severity evaluated by a heart valve team conference. According to guidelines only patients 75 years or older will be considered, however clinical factors can and will be the prevalent factor for determining this
We are excluding patients with:
1. Permanent atrial fibrillation
2. Left bundle branch block
3. Concominant moderate or severe valvular disease other than AS
4. Women of childbearing potential
5. Inability to provide informed consent.
Data and biological material
Basic demographic data including medical history, medicine status, smoking status, NYHA- and CSS-classification, height and weight are obtained at baseline.
2D and 3D-data, doppler and tissue doppler, strain and speckle tracking before TAVR and after.
Cardiac CT-scan with contrast before and after TAVR.
Invasive pressure measurement before and after deployment of the new aortic valve.
Collaborating researchers and departments
Department of Cardiology, Odense University Hospital
- Professor Jacob Eifer Møller, MD, DMSc, PhD.
- Consultant Jordi S. Dahl, MD, PhD, DMSc
- Consultant Kristian A. Øvrehus, MD, PhD
- Rasmus Carter-Stoch, MD, PhD
- Nils Mogensen, MD
Publications associated with the project
Non so far