Quartet Lead and Resynchronization Therapy Options

Study Overview
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Brief Summary
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The purpose of this Clinical Trial is to determine the percentage of patients whose hemodynamic response improves with the different configurations offered by the new Quartet® left ventricular lead, as a result of its four electrodes, with respect to the configurations offered by a standard bipolar lead. Furthermore, the optimal stimulation configuration will be determined from a comparison with traditional configurations.

Detailed Description
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This is a prospective, non-randomised, multi-centre, national, interventional clinical trial of a medical device. This trial involves two visits: one at the beginning of the study, which will be undertaken in the seven days following implant, and another visit at 6 months after enrollment. It is recommended that the enrollment visit is undertaken as soon as possible after implantation, although the time window allows the timing to be adapted to each centre's standard practice. Resynchronization therapy in those patients suitable for participation in this trial is expected to begin once this enrollment visit has been completed. Once data collection at enrollment visit has been completed, final device programming will be based on each investigator's criteria and will be undertaken following the standard practice of each centre.

Official Title
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QUARTET LEAD AND RESYNCHRONIZATION THERAPY OPTIONS To Investigate the Stimulatory Possibilities Offered by the Different Configurations Available for the Quartet Lead and Their Effect on Haemodynamic and Clinical Response.

Conditions
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Heart Failure

Intervention / Treatment
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* Device: Cardiac Resynchronization Therapy Defibrillator


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with a Cardiac resynchronization Therapy Defibrillator device (CRT-D) and a Quartet® quadripolar electrode from St Jude Medical (used in Single Site Pacing mode) implanted in the left ventricle. Patients who have provided written informed consent Patients who are in sinus rhythm. Patients older than 18 years of age. Exclusion Criteria: Patients in atrial fibrillation at the time of the echocardiographic study of the enrollment visit. Patients with valvular disease. Patients in functional class New York Heart Association (NYHA) IV Patients for whom echocardiography images suitable for determining the cardiac output cannot be obtained. Patients whose device has been changed/upgraded. Pregnant patients. Patients who do not fulfill all the inclusion criteria. Patients who are unable to provide written informed consent

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: Supportive Care
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: CRT therapy<br>Cardiac Resynchronization Therapy Defibrillator (CRT-D) | Device: Cardiac Resynchronization Therapy Defibrillator<br>* Cardiac Resynchronization Therapy Defibrillator<br>* Other names: Quartet®: Tetrapolar left ventricular lead. Model 1458Q.;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Patients Whose Cardiac Output (CO) Value in Acute, as Measured Echocardiographically, Improves With the Different Stimulation Vectors Offered by the Quartet® Left Ventricular Electrode. |  | Enrollment visit (in the seven days after implantation of the device) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percent Difference Between the Best CO From Non-traditional Vectors and Best CO From Traditional Vectors | In patients with best CO obtained from Non-traditional, to calculate the percent difference between the best CO from Non-traditional vectors and best CO from Traditional vectors, vectors.This percentage was the CO from Non-traditional vectors minus CO from Traditional vectors then divided by CO from Traditional vectors. The Quartet® lead has 4 poles: Distal (D1), Mid 2 (M2), Mid 3 (M3) and Proximal (P4). The 3 Traditional vectors are the traditional configurations available in a standard bipolar lead: D1-M2, D1-Right Ventricular Coil (RVC) and M2-RVC. The 7 Non-traditional vectors are the additional configurations available in a Quartet® lead: D1-P4, M2-P4, M3-M2, M3-RVC, M3-P4, P4-M2 and P4-RVC. | At enrollment | 
| Cardiac Output (CO) With Different Configurations at Enrollment | Means of baseline non-paced CO, best CO obtained from traditional configurations and best CO obtained from all quadripolar configurations at enrollment. | Enrollment visit (in the seven days after implantation of the device) | 
| Capture Threshold | Capture and phrenic threshold data will be recorded for each of the stimulation vectors studied. Attempts will also be made to avoid phrenic stimulation in those patients who suffer from it, whilst maintaining good capture thresholds, by changing between the new configurations offered by the Quartet® electrode. | Enrollment visit (in the seven days after implantation of the device) | 
| Capture Threshold | Capture and phrenic threshold data will be recorded for each of the stimulation vectors studied. Attempts will also be made to avoid phrenic stimulation in those patients who suffer from it, whilst maintaining good capture thresholds, by changing between the new configurations offered by the Quartet® electrode. | 6 months post-implant | 
| Number of Vectors With Phrenic Nerve Stimulation (PNS) | Capture and phrenic threshold data will be recorded for each of the stimulation vectors studied. Attempts will also be made to avoid phrenic stimulation in those patients who suffer from it, while maintaining good capture thresholds, by changing between the new configurations offered by the Quartet® electrode. | Enrollment visit (in the seven days after implantation of the device) | 
| Number of Vectors With Phrenic Nerve Stimulation (PNS) | Capture and phrenic threshold data will be recorded for each of the stimulation vectors studied. Attempts will also be made to avoid phrenic stimulation in those patients who suffer from it, whilst maintaining good capture thresholds, by changing between the new configurations offered by the Quartet® electrode. | At 6 months | 
| Number of Patients With PNS in All Vectors | To calculate the number of patients that exhibit PNS in all traditional vector | At enrollment | 
| Number of Patients With PNS in All Vectors, That Could be Avoided With a Non-traditional Vector | To calculate the number of patients, who exhibit PNS in all traditional vector, in which PNS could be avoided using a non-traditional vector | At enrollment | 
| Number of Patients With PNS in All Vectors | To calculate the number of patients that exhibit PNS in all traditional vector | At 6 months | 
| Number of Patients With PNS in All Vectors, That Could be Avoided With a Non-traditional Vector | To calculate the number of patients, who exhibit PNS in all traditional vector, in which PNS could be avoided using a non-traditional vector | At 6 months |