CPET Predicts Long-term Survival and Positive Response to CRT

Study Overview
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Brief Summary
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The study tested the usefulness of cardiopulmonary exercise test (CPET) in selection of potential responders to CRT.

Detailed Description
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Cardiac resynchronization therapy (CRT) is an acknowledged therapy of selected patients with heart failure (HF). One of the unresolved problems is high percentage of non-responders to CRT, reaching 40%. No single parameter, helpful in identifying non-responders prior to CRT implantation, was found. The study included patients with HF of ischemic or non-ischemic etiology, in NYHA class II-IV, EF≤35% and QRS≥120ms. All the patients had CRT implanted. Clinical evaluation, CPET and NT-proBNP levels measurement were performed before CRT implantation and after 3-6 months. Improvement in HF symptoms of one or more NYHA class correlated with two-years survival. It was used as the criterion of positive response to CRT.

Official Title
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Cardiopulmonary Exercise Test Predicts Long-term Survival and Positive Response to Cardiac Resynchronization Therapy.

Conditions
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Heart Failure With Reduced Ejection Fraction

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: HF in class III or IV according to New York Heart Association (NYHA) in the course of ischemic (ICM) or non-ischemic cardiomyopathy (NICM), QRS complex duration ≥ 120ms, EF ≤35% and dilatation of the left ventricle diastolic diameter >55mm (LVdD), according to the ESC guidelines in 2007 HF in NYHA class II, LBBB with QRS complex duration ≥ 150 ms according to the guidelines update in 2010 optimal pharmacotherapy of HF in the period of three months prior to the study entry. the expected survival of the patient > 1 year. Exclusion Criteria: severe chronic obstructive pulmonary disease (FEV1 <30%) inability to perform a stress test on a treadmill

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Responders<br>Patients with improvement of at least one NYHA class after one year from CRT. | |
| Non-responders<br>Patients with no improvement of at least one NYHA class after one year from CRT. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Death | All cause death, data from hospital entries and phone follow-up . | Follow up within 5 years from CRT | 
| Heart transplantation | Heart transplantation as the definitive therapy of end-stage heart failure. | Follow up within 5 years from CRT | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Positive response to CRT | Positive response to CRT was defined as the improvement in heart failure symptoms of 1 or more NYHA classes | Follow up within 1 year from CRT | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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heart failure, cardiac resynchronization therapy, cardiopulmonary exercise test, responders to CRT, non-responders to CRT, survival prognosis after CRT