Comparing Rate Response With CLS Versus Accelerometer ICD Settings in Heart Failure Patients With BIOTRONIK CRT-Ds

Study Overview
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Brief Summary
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Dr. Jonathan Hsu and Dr. Eric Adler are conducting a research study to find out more about how implantable cardiac defibrillator (ICD) settings can be adjusted to improve patient cardiovascular health and quality of life. Patients are being asked to participate in this study if they have a history of heart failure and have or are scheduled to be implanted with a BIOTRONIK ICD that is capable of closed loop stimulation (CLS). CLS is a device setting that works with the cardiovascular system to optimize their heart rate during physical activity. This study is comparing BIOTRONIK's CLS setting to a standard accelerometer setting, which also is able to adjust the heart rate by movement sensors, when necessary. This study has been initiated by Dr. Hsu and Dr. Adler and is financially supported by BIOTRONIK, Inc. There will be approximately 15 participants in this trial.

Detailed Description
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This study is a prospective, randomized, single-blind crossover study intended to enroll patients who are implanted or are scheduled to be implanted with a Biotronik CLS and accelerometer capable CRT-D device. Patients will serve as their own control group with regard to modes of rate-adaptive pacing. Patients with a previously implanted Biotronik CRT-D device with CLS-capability will be recruited from health care institutions in San Diego and all dedicated functional testing will be performed at the University of California, San Diego (UCSD). The goal enrollment target for analysis will be 15 patients, with up to 20 patients enrolled to allow for withdrawals. The purpose of this study is to evaluate whether changes to an implanted ICD can improve the functional status of patients with suspected chronotropic incompetence (CI). CI is a condition in which the heart rate is unable to adequately respond to meet the patient's physical demands, such as walking, climbing stairs, or doing household chores. CI is common in patients with cardiovascular disease, particularly in patients with heart failure. Common clinical management of patients with suspected CI is to activate an accelerometer setting in the cardiac resynchronization therapy with defibrillator (CRT-D) device. An accelerometer will adjust the heart rate to fit the physiological circumstances and needs of the patient based on patient movement only. BIOTRONIK is a company that has developed a novel technology included in the settings for CRT-D devices that offers CLS as an alternative to a standard accelerometer. CLS utilizes sensed electrical properties of the heart in order to assess what may be the best heart rate for both physical and mental demands. This study is designed to compare whether patients will benefit from CLS when compared with standard accelerometer technology.

Official Title
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Rate Response With CLS Versus Accelerometer and Effect on Both Subjective Symptoms and Objective Outcomes in a Heart Failure Population Implanted With Cardiac Resynchronization With Defibrillator Device: The CLASS Trial

Conditions
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Heart Failure, ICD, Chronotropic Incompetence

Intervention / Treatment
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* Device: CLS Mode on Biotronik CRT-D
* Device: Accelerometer Mode on Biotronik CRT-D


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with a BIOTRONIK CRT-D device (capable of CLS and accelerometer rate responsive pacing) Patients at least 18 years old Patients who have plausible symptoms of CI based on previous monitoring and clinical symptoms Exclusion Criteria: Pregnant patients Patients who are unwilling/unable to provide informed consent Patients who are unable to complete study related procedures Current persistent atrial fibrillation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 99 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: CLS Mode on Biotronik CRT-D<br>All 15 patients will be randomized to this group. Their device will be set in the CLS mode for 1 week. | Device: CLS Mode on Biotronik CRT-D<br>* Setting changed and monitored. Quality of life evaluated through CPET, 6 Minute Walk Test, and Rand 36 Questionnaire.<br>|
| Active Comparator: Accelerometer Mode on Biotronik CRT-D<br>All 15 patients will be randomized to this group. Their device will be set in the accelerometer rate responsive mode for 1 week. | Device: Accelerometer Mode on Biotronik CRT-D<br>* Setting changed and monitored. Quality of life evaluated through CPET, 6 Minute Walk Test, and Rand 36 Questionnaire.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Six-minute Walk Distance (6MWD) Test | Cardiovascular health benefits were measured by the six-minute walk distance (6MWD) test. The 6MWD is a standardized field test to evaluate functional exercise performance. Subjects are instructed to walk as far as possible in 6 min on a flat surface. This test was performed twice, once at the end of each intervention period. | Measured on day 14 and day 21. | 
| RAND-36 Questionnaire | Quality of life of subjects was measured by the RAND-36 which is a generic 36-item questionnaire that measures eight health-related domains stratified by physical health (physical functioning, role limitations due to physical health, pain, and general health) and emotional health (vitality, role limitations due to emotional problems, social functioning, and mental health). Each scale is directly transformed into a 0-100 scale for a total score range of 0-800. Higher scores represent a more favorable health status. This test was performed twice, once at the end of each intervention period. | Performed on day 14 and day 21. | 
| Cardiopulmonary Exercise Testing (CPET) | Cardiovascular health benefits were determined by measuring the peak heart rate (HR) during Cardiopulmonary exercise testing (CPET). The CPET is performed on a standard treadmill according to the Naughton protocol. During the test, patients inspired room air through a low-resistance mask, and expired oxygen and carbon dioxide partial pressures were measured with a gas analyzer. HR was recorded every 30 seconds during exercise. All patients were encouraged to exercise to maximal effort. This test was performed twice, once at the end of each intervention period. | Performed on day 14 and day 21. | 
| Patient Preference | At the end of the study, patients were asked about personal preference regarding CLS over DDDR. | Performed on day 21. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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defibrillator, heart failure, ICD, CRT-D, cardiac resynchronization therapy, rate response, CLS, closed-loop stimulation, accelerometer, chronotropic incompetence