Cardiomyopathies, Conditioning, Heart Rate
Conditions
Brief summary
This project utilizes a novel cardiac pacing approach hypothesized to initiate beneficial cardiac conditioning and remodeling over a period of time.
Detailed description
The project studies subjects with non-ischemic cardiomyopathy who have a pacing device already implanted. Subjects randomized to the pacing intervention versus a sham intervention will be compared for various symptomatic, functional and other outcomes. Each subject will undergo baseline quality of life/symptom questionnaires and clinical testing for cardiac functional/structural effects and exercise tolerance, then the intervention vs. sham (subjects blinded to their category), followed by repeat questionnaires and clinical testing. Medical record review will be undertaken to establish demographic variables, baseline and follow up testing results.
Interventions
OTHERnovel atrial pacing approach
See US Patent #10987516. An atrial pacing method that preserves atrioventricular and interventricular synchrony to reproduce an exercise-typical envelope of heart rate.
OTHERsham pacing approach
A pacemaker/ICD interrogator/programmer will be used to simulate changes in pacing rate over the same time period as the intervention group but the programming changes will not actually be implemented and not change in paced heart rate will occur.
Sponsors
Denise Hodgson-Zingman
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
Subjects will be unaware of their group assignment. Investigators delivering the intervention vs. sham will be aware. Analysts processing primary data (serum testing, echocardiographic dimensions, 6-min walk distance, CPEX) will not be aware of group assignments.
Intervention model description
Subjects will be randomized in a single-blinded fashion to intervention vs. sham treatment
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Non-Ischemic Cardiomyopathy * Ejection Fraction \</= 35% despite at least 3 months stable standard medical management * New York Heart Association Class II-III symptoms * Dual chamber implantable cardioverter defibrillator in place or Biventricular ICD in place (over 3 months old) * Normal Atrioventricular conduction or Biventricular ICD * QRS \< 120 msec (inherent conduction or paced with BiV ICD)
Exclusion criteria
* Age \< 18 years * Inability to ambulate safely * Congenital or primary valve disease * Left Ventricular thrombus * Severe peripheral arterial disease * Admission for life-threatening condition (eg heart failure, stroke) in the past 3 months * Major surgery in the past 3 months or anticipated during the period of the trial * Paced or intrinsic QRS \>120 msec * Life expectancy \< 1 year * Hemodialysis * Hematocrit \< 30% * Severe Chronic lung disease * Pregnancy * ICD battery longevity \< 1 year * Unsuppressed atrial arrhythmias * Already participating in an exercise programusion Criteria
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Quality of life/symptom score | 4 weeks after start of the protocol | Minnesota Living with Heart Failure Score (range 0-105, higher scores indicate worse quality of life) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| diastolic blood pressure | every 5 minutes during intervention/sham in weeks 1-4 of the protocol | systolic blood pressure (mmHg) as a continuous variable |
| Oxygen saturation | every 5 minutes during intervention/sham in weeks 1-4 of the protocol | oxygen saturation by pulse oximeter (%) as a continuous variable |
| systolic blood pressure | every 5 minutes during intervention/sham in weeks 1-4 of the protocol | systolic blood pressure (mmHg) as a continuous variable |
| MACE | 4 weeks and 4 months after start of the protocol | Major adverse cardiac events: composite of total death, MI, stroke, hospitalization due to heart failure, revascularization |
| six minute walk | at the time of enrollment, and at 4 weeks after start of the protocol | distance ambulated in 6 minutes (meters) |
| cardiac output | every 5 minutes during intervention/sham in weeks 1-4 of the protocol | cardiac output (liters/minute) as measured by thoracic impedance and reported as a continuous variable |
Countries
United States
Outcome results
None listed