Effects of Levothyroxine Supplementation in Patients With Systolic Heart Failure and Subclinical Hypothyroidism

Study Overview
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Brief Summary
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The purpose of this study is to determine whether levothyroxine supplementation is beneficial in patients with systolic heart failure and subclinical hypothyroidism on the functional class evaluated with a 6 minute walk test.

Detailed Description
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Forty patients with systolic heart failure and subclinical hypothyroidism will be include in a open label trial. They will receive levothyroxine supplementation to determine if their functional class will be affect.

Official Title
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Beneficial Effects of Levothyroxine Supplementation in Patients With Systolic Heart Failure and Subclinical Hypothyroidism

Conditions
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Systolic Heart Failure, Sub-clinical Hypothyroidism

Intervention / Treatment
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* Drug: Levothyroxine supplementation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Biochemical diagnosis of subclinical hypothyroidism (TSH between 3.5 and 10 with a normal T4) Systolic heart failure with New-York Heart Association (NYHA) class II or III Left ventricular ejection fraction under 40% Stable heart failure for the past 3 months (no IV furosemide or hospital admission) Beta-blockers and ACE inhibitors titrated to the maximum tolerated dose Exclusion Criteria: Isolated diastolic heart failure Awaiting cardiac resynchronisation therapy Impossibility to perform the 6 minutes walk test Active cancer / Life expectancy under 18 months Treatment with amiodarone

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Levothyroxine<br>Levothyroxine supplementation | Drug: Levothyroxine supplementation<br>* T4 supplementation for heart failure patients with subclinical hypothyroidism.<br>* Other names: T4 supplementation;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Performance at the 6 minutes walk test |  | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference of the brain natriuretic peptide measurement |  | 6 months | 
| Difference of activin a measurement |  | 6 months | 
| Difference of myostatin measurement |  | 6 months | 
| Increase in heart rate measurement | Absence / Presence of tachycardia (heart rate > 100 beat per minute) at baseline and 6 months | 6 months | 
| Difference of systolic and diastolic function on transthoracic echocardiogram |  | 6 months | 
| Arhythmic (ventricular arrhythmias and supraventricular arrythmias) and ischemic events (myocardial infarction, unstable angina and hospitalization for revascularization) |  | 6 months | 
| Normalisation of thyroid workup |  | 6 months |