Microvascular Dysfunction in Aortic Stenosis (PRIMID-AS)

The recruitment status of this study is unknown because the information has not been verified recently.
Verified August 2012 by University Hospitals, Leicester.
Recruitment status was  Recruiting
Sponsor:
Information provided by (Responsible Party):
University Hospitals, Leicester
ClinicalTrials.gov Identifier:
NCT01658345
First received: July 6, 2012
Last updated: August 6, 2012
Last verified: August 2012
  Purpose

Aortic stenosis (AS), or narrowing of the aortic valve, is the commonest condition requiring valve surgery in the developed world. It is currently not known what determines who will go on to develop symptoms. Exercise testing may be able to identify these patients better than the severity of the narrowing itself, but with some limitations.

The purpose of this study is to compare whether MRI scanning or exercise testing can better identify patients with AS who are likely to benefit from surgery.

Design: The investigators will measure blood flow to the heart muscle with MRI scanning and perform exercise testing in 170 patients with AS and follow them for up to up to 2 years. Expected outcomes: MRI scanning will more accurately identify those patients with AS who will need surgery during this period. Anticipated Health Benefits: improved selection of patients with AS who are likely to benefit from early surgery. This is likely to reduce deaths in such patients.


Condition
Aortic Stenosis

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Prognostic Importance of Microvascular Dysfunction in Asymptomatic Patients With Aortic Stenosis (PRIMID-AS)

Resource links provided by NLM:


Further study details as provided by University Hospitals, Leicester:

Primary Outcome Measures:
  • Typical AS Symptoms necessitating AVR. [ Time Frame: 12 months ] [ Designated as safety issue: No ]
  • Cardiovascular death. [ Time Frame: 12 months ] [ Designated as safety issue: No ]
  • Major adverse cardiovascular events (MACE) [ Time Frame: 12 months ] [ Designated as safety issue: No ]
    MACE: hospitalisation with heart failure, chest pain, syncope, arrhythmia or stroke


Secondary Outcome Measures:
  • Individual components of primary composite outcome measures. [ Time Frame: Upto 2 years. ] [ Designated as safety issue: No ]
    Typical symptoms requiring referral for AVR, cardiovascular death, Major adverse cardiovascular events.

  • Development of typical symptoms, AVR, death from any cause or MACE during the entire study period. [ Time Frame: 2 years ] [ Designated as safety issue: No ]

Biospecimen Retention:   Samples With DNA

With consent, a blood sample (up to 50ml) will be drawn and banked for prospective research studies. All research projects will be related to cardiovascular disease and approved by the Trial Steering Committee (TSC) or a committee delegated this responsibility by the TSC.

All tissue will be collected, stored and disposed of in accordance with the Codes of Practice as laid out by the Human Tissue Authority.


Estimated Enrollment: 170
Study Start Date: April 2012
Estimated Study Completion Date: July 2014
Estimated Primary Completion Date: July 2013 (Final data collection date for primary outcome measure)
Detailed Description:

Surgical AVR remains the universally accepted management for symptomatic aortic stenosis (AS). However, the best management of severe aortic stenosis, in the absence of symptoms, remains one of the most controversial areas in modern Cardiology.

Exercise testing can identify asymptomatic patients with AS at increased risk, but with limited specificity. In a BHF funded project, the investigators have identified that cardiac MRI measured Myocardial Perfusion Reserve (MPR) may be a novel imaging biomarker in AS. MPR was the only independent predictor of aerobic exercise capacity (peak VO2) in patients with severe AS and was also inversely related to symptomatic status.

In this multi-centre, observational, cohort outcome study, the investigators will follow 170 patients with asymptomatic moderate to severe AS for a minimum of 12 months, and determine whether MPR is a better predictor of outcome than exercise testing, elucidate the mechanisms contributing to symptom development in AS and establish the determinants of MPR in AS. Patients will be recruited from tertiary Cardiac centres, as well as regional hospitals. Comprehensive CMR with adenosine stress to determine LV mass and function, focal and diffuse fibrosis and MPR; cardiopulmonary exercise testing (peak VO2 and exercise symptoms); rest and exercise echocardiography (AS severity, valve compliance) and NT-proBNP will be performed. The study will be run in conjunction with the Glasgow CTU. Investigations will be analysed blind to patient status and data will be entered in a validated database. Statistical analysis will be performed under the supervision of Prof. Ian Ford. The relationship between MPR and exercise testing with 1-year outcome will be analysed using logistic regression. Paired comparisons of the specificities of the two approaches on the same dataset will be carried out using McNemar's test.

The primary hypothesis is that MPR will be a better predictor of adverse outcome than exercise testing.

  Eligibility

Ages Eligible for Study:   18 Years to 85 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population

Cardiology outpatients department and echocardiography department.

Criteria

Inclusion Criteria:

  1. Moderate-severe aortic stenosis (2 or more of: AVA < 1.5cm2, peak PG >36mmHg or mean PG > 25mmHg).
  2. Asymptomatic.
  3. Age > 18 years and < 85 years.
  4. Prepared to consider AVR if symptoms develop.
  5. Ability to perform bicycle exercise test

Exclusion Criteria:

  1. History of CABG, MI, angiographic CAD (> 50% luminal stenosis if previously undertaken).
  2. Severe valvular disease other than AS.
  3. Previous Valve surgery
  4. Persistent Atrial Fibrillation or Flutter
  5. History of Heart Failure
  6. Severe Asthma.
  7. Severe renal impairment eGFR < 30ml/min.
  8. Planned aortic valve replacement.
  9. Significant LV systolic dysfunction (EF < 40%)
  10. Any absolute contraindication to CMR
  11. Any absolute contraindication to Adenosine
  12. Participation in an Interventional Clinical Trial at Inclusion.
  13. Other medical condition that limits life expectancy or precludes AVR.
  14. Pregnancy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01658345

Contacts
Contact: Anvesha Singh, MBChB +44 300 303 1573 ext 3422 as707@leicester.ac.uk

Locations
United Kingdom
Glenfield Hospital Recruiting
Leicester, Leicestershire, United Kingdom, LE3 9QP
Contact: Anvesha Singh, MBChB       as707@leicester.ac.uk   
Principal Investigator: Gerry P McCann, MBChB, MD         
Leeds General Infirmary Not yet recruiting
Leeds, West Yorkshire, United Kingdom, LS1 3EX
Contact: John Greenwood, MBChB, PhD    +44 113 2432799    J.Greenwood@leeds.ac.uk   
Principal Investigator: John Greenwood, MBChB, PhD         
University of Glasgow Not yet recruiting
Glasgow, United Kingdom, G12 8QQ
Contact: Colin Berry, BSc, MBChB, PhD    +44 1413301671    Colin.Berry@glasgow.ac.uk   
Principal Investigator: Colin Berry, BSc, MBChB, PhD         
Sponsors and Collaborators
University Hospitals, Leicester
Investigators
Principal Investigator: Gerry P McCann, MBChB, MD University of Leicester
  More Information

Publications:
Responsible Party: University Hospitals, Leicester
ClinicalTrials.gov Identifier: NCT01658345     History of Changes
Other Study ID Numbers: 87768
Study First Received: July 6, 2012
Last Updated: August 6, 2012
Health Authority: United Kingdom: National Institute for Health Research
United Kingdom: Research Ethics Committee

Keywords provided by University Hospitals, Leicester:
aortic stenosis
asymptomatic
microvascular dysfunction
Cardiac MRI

Additional relevant MeSH terms:
Aortic Valve Stenosis
Constriction, Pathologic
Cardiovascular Diseases
Heart Diseases
Heart Valve Diseases
Pathological Conditions, Anatomical
Ventricular Outflow Obstruction

ClinicalTrials.gov processed this record on October 22, 2014