Dobutamine Stress Echocardiography in Cardiac Resynchronization Therapy (CRT) Patients Selection

Study Overview
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Brief Summary
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While cardiac resynchronization therapy (CRT) has a well demonstrated therapeutic effect in selected patients with advanced heart failure (HF) on optimized drug therapy, non-responder rate remains high. The low-dose dobutamine stress-echo (DSE) test to predict positive response to CRT (LODO-CRT) trial is designed to improve patient selection for CRT.

Detailed Description
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LODO-CRT is a multicenter prospective study enrolling HF patients with conventional indication to CRT (symptomatic stable NYHA class III-IV on optimized drug therapy, QRS≥120 msec, left ventricular (LV) dilatation, LVEF≤35%) is designed to assess the predictive value of LV contractile reserve (LVCR), determined through DSE, in predicting CRT response during follow-up. Assessment of CRT effects will follow two sequential phases: in phase 1 CRT response end-point is defined as left ventricular end-systolic volume (LVESV) reduction ≥ 10% at 6 months; in phase 2, both LVESV reduction and clinical status via a clinical composite score will be evaluated at 12 months follow-up. Predictive value of LVCR will be compared to other measures, such as LV dyssynchrony measures, through adjusted multivariable analysis. For the purpose of the study, target patient number is 270 patients (with 95% confidence, 80% power, α≤0.05). LVCR assessment, using low-dose DES test, should effectively predict positive response to CRT both in terms of the reverse remodeling process as well as favorable long-term clinical outcome. Moreover, the predictive value of LVCR will be compared to that of conventional intra-LV dyssynchrony measures.

Official Title
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Efficacy Of Low-Dose Dobutamine Stress-Echocardiography To Predict Cardiac Resynchronization Therapy Response

Conditions
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Heart Failure

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: severe HF despite optimized medical therapy NYHA functional class III-IV dilated cardiomyopathy of both ischemic and non-ischemic origin left ventricular ejection fraction (LVEF) <=35% QRS complex duration ≥120 ms normal sinus rhythm. Exclusion Criteria: younger than 18 years old unstable angina acute myocardial infarction coronary artery bypass graft (CABG) or percutaneous transluminal coronary angioplasty (PTCA) within the past 3 months already implanted with a conventional implantable pulse generator or with an implantable cardioverter defibrillator (ICD) previously implanted with a CRT device chronic permanent atrial arrhythmias

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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of patients showing left ventricular reverse remodelling. In particular, a 10% or greater reduction of the left ventricular end-systolic volume (LVESV) is the primary endpoint of the LODO-CRT study. |  | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical composite score, which combines changes in the NYHA class and global assessment with the information provided from the occurrence of major clinical events. |  | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Heart Failure, CRT, Dobutamine echocardiography