Clinical Predictive Value of Podocan and Wnt Pathway Regulatory Molecules on Maladaptive Left Ventricular Response in Aortic Stenosis
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 9
- 试验地点
- 1
- 主要终点
- Podocan level
研究概览
简要总结
Aortic stenosis is a major cause of morbidity around the world. Progressive aortic stenosis leads to cardiac hypertrophy as a compensatory response. A maladaptive response may lead to heart failure at varying degrees of severity of aortic stenosis in individual patients. The predicting factors for the occurrence of a maladaptive response are not well defined. Therefore current medical therapy for aortic stenosis is considered insufficient and may actually cause harm. The only effective therapy for severe, symptomatic aortic stenosis is aortic valve replacement. It has been found in an experimental study that Podocan determines the degree of cardiac hypertrophy in response to pressure overload via the Wnt-pathway. The possible prognostic role of secreted circulating Wnt modulators in aortic stenosis has also recently gained attention. This project will attempt to establish the prognostic role of circulatory Podocan and Wnt modulators for maladaptive left ventricular response to aortic stenosis. This may help identify patients at particular risk to develop left ventricular dysfunction with aortic stenosis and improve understanding of the mechanisms of left ventricular remodeling in aortic stenosis. Hence, this may also later act as an important background in finding more effective therapies to prevent or delay maladaptive left ventricular response in aortic stenosis.
详细描述
Valvular heart disease is a common clinical indication to assess patients with cardiac MRI. Cardiac MRI is comprehensive study that uses multiple imaging sequences.Cardiac MRI is indicated to image native and prosthetic aortic valves. Planimetry of the aortic valve is valuable for determination of the severity of aortic stenosis. Cardiac MRI is the most accurate and reproducible imaging modality to assess left ventricular function and mass. Left ventricular (LV) function is a primary determinant of outcomes following aortic valve replacement. LV mass is increased in severe aortic stenosis. Variations in the morphology of hypertrophy in response to aortic stenosis have been detected by cardiac MRI. Cardiac MRI is commonly used to assess aortic stenosis in the context of discordant information from alternative imaging modalities and low gradient aortic stenosis.
It is expected that 100 participants will be enrolled in the study over 24 months. This is sample size was agreed upon after discussion with the statistics team.
Patients who agree to participate will provide informed consent prior to their cardiac MRI. A 6 minute walk test to measure baseline functional status will be done after consent, preferably just prior to reporting to the MRI suite for their scheduled test. Standard cardiac MRI will be obtained. All patients having a cardiac MRI have an IV line placed as normal procedure. When the line has been placed, prior to contrast infusion (if applicable)or other medication administration, blood samples will be collected to test for circulatory Podocan and Wnt pathway molecules. Approximately 20 cc will be drawn in total. All specimens will be sent to the experimental lab of Dr. Paul Klotman at Baylor Medical Center. All of the Podocan & Wnt pathway effectory molecules assays will be completed by Dr. Klotman's lab.
The following measurements will be collected from the cardiac MRI:
LV end diastolic (ED) volume: ml LV ED index: ml/m2 LV end systolic (ES) volume: ml LV ES index: ml/m2 LV ejection fraction (EF): % LV Stroke Volume: ml LV Stroke Index: ml/m2 LV Cardiac Output: L/min LV Cardiac Index: L/min/M2 LV Mass: g LV Mass index: g/m2
研究设计
- 研究类型
- Observational
- 观察模型
- Case Only
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age 18 or greater
- •Scheduled for Cardiac MRI
- •Patients with known aortic valve area of less than 1 cm² on echocardiogram
- •Able to provide informed consent
- •Ambulatory and expected to be able to complete 6 minute walk test
排除标准
- •Other significant (moderate or severe) valvular heart disease
- •Unable to complete 6 minute walk test (ex. Wheelchair bound)
结局指标
主要结局
Podocan level
时间窗: Day 1
All patients having a cardiac MRI have an IV line placed as normal procedure. When the line has been placed, prior to contrast infusion (if applicable)or other medication administration, blood samples will be collected to test for circulatory Podocan .
Wnt Pathway molecule levels
时间窗: Day 1
All patients having a cardiac MRI have an IV line placed as normal procedure. When the line has been placed, prior to contrast infusion (if applicable)or other medication administration, blood samples will be collected to test for circulatory Wnt pathway molecules
次要结局
- Wnt Pathway molecule levels(18 months)
- 6 minute walk test(Day 1)
- Podocan level(18 months)
研究者
Daniel Katz
Attending Physician - Cardiology
Bassett Healthcare