A Randomized Clinical Trial of Metoprolol in Participants With Mitral Regurgitation.

Beta Blockade in Mitral Regurgitation

Mitral valve regurgitation (leakage of the mitral valve of the heart) is frequent and currently there is no specific medical therapy. Mitral regurgitation is a slowly progressive disease that frequently requires surgical treatment. This randomized clinical trial will use Metoprolol, a common beta-blocker medication, to determine if medical treatment impacts mitral valve disease progression.

Study Overview

• Status: Completed
• Conditions: Heart Valve Diseases
• Intervention / Treatment: Drug: metoprolol succinate

Detailed Description

Background: Mitral regurgitation (MR) is frequent and its prevalence is increasing with aging of the population. Organic MR, due to primary valvular lesions has severe consequences determined by its degree, with left ventricular (LV) remodeling and dysfunction, left atrial (LA) enlargement, leading to poor clinical outcome. Surgery can eliminate MR, but carries notable risks and is not applicable to all patients. Recent animal data suggest that beta-blockade in organic MR has significant positive effect, particularly on LV remodeling. Therefore, chronically decreasing MR, protecting LV and LA with beta-blockade are major goals of medical therapy. However, effects of chronic oral beta-blockade of human MR are uncertain and recent practice guidelines underscored these gaps in knowledge and did not recommend beta-blockade of MR. Hence, a trial of treatment of organic MR is needed. A large trial with mortality-morbidity end-points is desirable but premature without knowledge of magnitude of mechanistic effects of beta-blockade. The improvement of these intermediate end-points, mechanistically linked to outcome, is measurable with non-invasive quantitative techniques and forms the basis of the present clinical trial proposal. Hypothesis: Chronic beta-blockade therapy using Metoprolol weighed against placebo produces a sustained reduction of the consequences of organic MR. Specific aims are that treatment improves a) degree of MR (decreases regurgitant volume, primary end-point), b) LV remodeling (decreases LV end-diastolic volume index, second end-point), and c) LA enlargement (decreases LA volume, third end-point) as compared to placebo. Population: Patients with MR organic (intrinsic valve disease), isolated (no other valve disease) d moderate (regurgitant volume *30 mL/beat). Methods: A randomized clinical trial, placebo controlled, double-blind, without crossover, of 12 months oral treatment with potent beta-blockade (Metoprolol XL 50 to 200mg QD) titrated to the maximally tolerated dose. The trial is preceded by an acute study to determine tolerance. End-points are measured by Doppler-Echocardiography for quantitation of MR (regurgitant volume) using combination of 3 simultaneous methods (quantitative Doppler, two-dimensional echocardiography, proximal flow convergence) and echocardiography for LV and LA volume measurement. In addition cardiopulmonary exercise testing will measure peak O2 consumption at baseline and follow-up. This study seeks to enroll a total of 60 patients. The analysis will be based on intention to treat and compare changes in regurgitant volume, LV end-diastolic volume index and LA volume measured after one year of treatment with active drug or placebo. The results of this clinical trial should provide strong evidence regarding medical treatment of patients with organic MR and define future strategies to minimize mortality and morbidity of organic MR.

• Study Type: Interventional
• Enrollment (Anticipated): 60
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Minnesota
    • Rochester, Minnesota, United States, 55905
      • Mayo Clinic

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion criteria: Patients a) 21 years old or older, with b) MR observed with color flow imaging, c) due to organic mitral valve disease demonstrated by Echocardiography (not normal valve as in functional or ischemic MR), c) isolated (no valve disease other than functional tricuspid regurgitation by Doppler-Echocardiography), d) pure (no mitral stenosis by Doppler-Echocardiography), e) quantifiable by Doppler-Echocardiography, f) of degree * moderate, defined as RVol * 30 mL/beat, g) occurring on native valves, h) with echocardiographic imaging allowing assessment of LA and LV, and i) asymptomatic (or mildly symptomatic but not considered as candidates for immediate surgery by their attending physician).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Degree of mitral regurgitation, assessed as the regurgitant volume, at baseline and 12 months	baseline & 12 months

Secondary Outcome Measures

Outcome Measure	Time Frame
Left ventricular end-diastolic volume index at baseline and 12 months	baseline & 12 months
Left atrial end-diastolic volume at baseline and at 12 months	baseline & 12 months

Collaborators and Investigators

• Sponsor: Mayo Clinic
• Collaborators: AstraZeneca
• Investigators: Principal Investigator: Maurice E Sarano, M.D., Mayo Clinic

Study record dates

Study Major Dates

• Study Start: July 1, 2004
• Primary Completion (Actual): July 1, 2007
• Study Completion (Actual): July 1, 2007

Study Registration Dates

• First Submitted: September 12, 2005
• First Submitted That Met QC Criteria: September 12, 2005
• First Posted (Estimate): September 14, 2005

Study Record Updates

• Last Update Posted (Estimate): July 24, 2008
• Last Update Submitted That Met QC Criteria: July 23, 2008
• Last Verified: July 1, 2008

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Mitral Valve Insufficiency; Heart Valve Diseases; Physiological Effects of Drugs; Adrenergic beta-Antagonists; Adrenergic Antagonists; Adrenergic Agents; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Anti-Arrhythmia Agents; Antihypertensive Agents; Autonomic Agents; Peripheral Nervous System Agents; Sympatholytics; Adrenergic beta-1 Receptor Antagonists; Metoprolol
• Other Study ID Numbers: 960-04; IRUSMETO0047, IRB 960-04