Assessment of Myocardial Tissue Damage in Aortic Stenosis

Assessment of Myocardial Tissue Damage in Aortic Stenosis for Risk Stratification

Aortic stenosis (AS) is the most common valve disease in the United States and most common indication for valve replacement surgery. Anatomical and hemodynamic severity of AS is insufficient for elucidating patients' prognosis. Therefore, the decision about the optimal timing of surgical intervention remains critical. However, the changes in structure and electrical activity of the cardiac muscle can be assessed by noninvasive imaging and electrocardiography (ECG). Degenerative myocardial changes characterized by fibrosis or collagen deposits are frequently observed in AS patients and have a negative impact on patient outcomes. In this project, our objective is to determine whether echocardiographic image analysis of integrated backscatter (IB), which can express changes in myocardial tissue composition (amount of fibrosis) based on its ultrasound reflectivity, global left ventricular (LV) load as measured by Zva, and ECG analysis of the duration of the QRS interval have a role in risk stratification for AS patients and to apply those methods to identify which patients would benefit from surgical intervention.

The investigators hypothesize that 1) the severity of myocardial damage can discriminate the prognosis in patients with AS, and 2) IB, Zva, and QRS interval can be diagnostic measures of the severity of myocardial damage. The investigators will measure the severity of myocardial fibrosis using MRI (reference) in 50 patients and will test the diagnostic significance of IB (testing method). Zva, QRS duration, and conventional echocardiographic measures will also be tested for diagnosing severity of myocardial fibrosis.

Study Overview

• Status: Completed
• Conditions: Aortic Stenosis

• Study Type: Observational
• Enrollment (Actual): 59

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Scottsdale, Arizona, United States, 85259
      • Mayo Clinic

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 65 years and older (Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients referred for echocardiography in Mayo Clinic.

Description

Inclusion Criteria:

• Moderate or severe aortic stenosis determined by echocardiography
• Adults > 65 years old

Exclusion Criteria:

• Ejection fraction < 50%
• Valvular diseases of more than or equal to moderate degree other than aortic stenosis
• Prior myocardial infarction or coronary artery disease needs revascularization
• Atrial fibrillation (chronic)
• Pacemaker/defibrillator implanted
• Previous valve replacement performed
• Cardiomyopathy(HCM, infiltrative cardiomyopathy, constriction)
• Renal dysfunction (estimated GFR < 30ml/min/1.73m² or end stage renal failure)
• Patients with contraindication for MRI
• Patients with poor echocardiographic images

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Moderate aortic stenosis.
Severe aortic stenosis.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Presence of myocardial fibrotic change determined by MRI.	1 hour

Collaborators and Investigators

• Sponsor: Mayo Clinic
• Collaborators: American Heart Association
• Investigators: Principal Investigator: Hari Chaliki, MD, Mayo Clinic; Principal Investigator: Minako Katayama, MD, Mayo Clinic

Study record dates

Study Major Dates

• Study Start: August 1, 2013
• Primary Completion (Actual): June 1, 2016
• Study Completion (Actual): June 1, 2016

Study Registration Dates

• First Submitted: March 28, 2014
• First Submitted That Met QC Criteria: April 1, 2014
• First Posted (Estimate): April 2, 2014

Study Record Updates

• Last Update Posted (Estimate): August 17, 2016
• Last Update Submitted That Met QC Criteria: August 15, 2016
• Last Verified: August 1, 2016

More Information

Terms related to this study

• Keywords: MRI; echocardiography; aortic stenosis; myocardial tissue
• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Pathological Conditions, Anatomical; Aortic Valve Disease; Heart Valve Diseases; Ventricular Outflow Obstruction; Aortic Valve Stenosis; Constriction, Pathologic
• Other Study ID Numbers: 13-004385