Endocardial Pacing in On-table Non-responders in Cardiac Resynchronization Therapy

Study Overview
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Brief Summary
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The purpose of this study is to determine whether left ventricular endocardial pacing exhibits a greater acute hemodynamic response during biventricular pacing in patients who do not show this response to standard cardiac resynchronization therapy.

Detailed Description
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Cardiac resynchronisation therapy (CRT) with biventricular pacemakers and implantable cardiac defibrillators (ICD) has proven to be a valuable therapy in selected patients with systolic heart failure, ameliorating both morbidity and mortality. However, with current selection criteria and implant technique, about 20 to 30 % of patients remain non-responders. Non-responders might be due to failing selection criteria or methodology in casu echocardiography. However, an important number of non-responders may result of sub-optimal positioning of the left ventricular lead, remote from the site of delayed activation. Endocardial left ventricular stimulation may ameliorate the shortcomings of epicardial stimulation. The advantage of an endocardial approach is the absence of phrenic nerve stimulation which regularly complicates epicardial pacing, a more predictable pacing threshold and much less restriction to position the lead in the area of interest. Transseptal left ventricular endocardial pacing has already been used in patients in whom standard epicardial pacing was not applicable.

Official Title
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Non-Responders in Cardiac Resynchronization Therapy

Conditions
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Heart Failure

Intervention / Treatment
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* Procedure: temporary left ventricular endocardial pacing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥18y LVEF ≤35% QRS-duration ≥0.12 seconds NYHA functional class III or IV despite optimal medical therapy defined as use of angiotensin-converting enzyme inhibitors or angiotensin-II receptor blocker and beta-blockers unless they are not tolerated or contra-indicated sinus rhythm or atrial fibrillation Exclusion Criteria: episode of acute heart failure ≤3 months change in dosage of beta-blockers, angiotensin-converting enzyme inhibitors or angiotensin-II receptor blockers ≤3 months unstable angina pectoris, acute myocardial infarction, percutaneous intervention or coronary bypass surgery ≤3 months chronic atrial arrhythmias other than atrial fibrillation any mechanical or biological valve prosthesis atrial septal defect right-to-left shunt severe pulmonary hypertension (systolic pulmonary artery pressure >90 mmHg) uncontrolled arterial hypertension known allergy to sulphur hexafluoride end-stage renal or hepatic disease inability to provide written informed consent pregnancy or childbearing potential without use of birth-control measurements general contra-indications to magnetic resonance imaging

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
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: on-table non-responder<br>patients who do not show an improvement of more than or equal to 15% in LV dP/dtmax measured immediately after implantation of a cardiac resynchronization therapy device | Procedure: temporary left ventricular endocardial pacing<br>* a temporary pacemaker lead will be introduced through the aortic valve to evaluate the effect of left ventricular endocardial pacing. Four different pacing sites (basal and apical septal, basal and apical lateral) will be investigated with measurement of LV dP/dtmax. Afterwards, the endocardial pacing lead will be removed.<br>|
| No Intervention: on-table responders<br>patients who do show an improvement of more than or equal to 15% in LV dP/dtmax measured immediately after implantation of a cardiac resynchronization therapy device | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in acute hemodynamic response to CRT defined as an increase in LV dP/dtmax of ≥10% during left endocardial pacing compared to left epicardial pacing. |  | baseline and 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| improvement in NYHA functional class ≥1 |  | baseline and 3 months | 
| decrease in MLWHFQ of ≥9 points |  | baseline and 3 months | 
| decrease in LVESV of ≥15% |  | baseline and 3 months | 
| increase in LVEF of ≥5% |  | baseline and 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Electrophysiologic Techniques, Cardiac