The goal of this study is to test a new pacing method called anodal biphasic pacing (ABP) to determine if this pacing works as well-or better-than current pacing methods. This new method may improve how the heart works and reduce some of the problems caused by regular pacing. Current implantable pacemakers use a monophasic cathodal waveform to stimulate the heart. Monophasic cathodal pacing (MCP) waveforms slow conduction, impair contractility, cause inflammation, increase risk of atrial fibrillation, heart failure, and mortality. Anodal biphasic pacing (ABP) is an alternative waveform that can stimulate the heart. ABP preconditions the heart and then initiates cardiac contraction. ABP may address the limitations of MCP.
This study is a single-center, prospective, investigator-initiated, non-randomized, study that will investigate ABP in patients with structurally normal hearts and those with non-ischemic cardiomyopathy who are undergoing interventional cardiac procedure, generator exchange of dual chamber Cardiac implantable electronic device (CIED), or de novo implant or generator exchange of CIED with cardiac resynchronization therapy. Eligible participants, without heart disease and those with nonischemic cardiomyopathy, undergoing CIED implant or generator exchange or interventional cardiac procedure at Boston Medical Center will be screened and prospectively enrolled. Participants will be stratified by left ventricular ejection fraction (EF): those with severely reduced EF (≤35%), mid-range EF (\> 35%-49%) and normal EF (EF≥ 50%). Primary efficacy objectives: 1. To identify which patient populations have the greatest and most consistent hemodynamic benefit from ABP as compared with cathodal pacing. 2. To confirm that ABP does not negatively impact non-responders. 3. To define the ideal anodal biphasic waveform characteristics (amplitude and pulse width) that maximizes the positive effect in subjects who demonstrate hemodynamic improvement ABP 4. To assess differences in capture thresholds between anodal biphasic and cathodal pacing. Secondary safety objectives: 1. To assess and characterize any ventricular arrhythmias associated with anodal biphasic in comparison to cathodal pacing. 2. To assess device safety 3. To assess procedure safety
Study Type
INTERVENTIONAL
Allocation
NON_RANDOMIZED
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
108
A pacing device that allows for programmable pulse waveforms to generate a predefined set of anodal biphasic waveforms. It possesses a battery-powered floating point gate array (FPGA) using software that allows flexibility in waveform configuration.
Boston Medical Center
Boston, Massachusetts, United States
Clinically significant maximum rate of pressure change maximum rate of pressure change within the left ventricle during its contraction phase- dP/dtmax.
Response will be expressed as a percent change in these measures with anodal biphasic pacing (ABP) as compared with cathodal pacing. A clinically significant hemodynamic response to pacing will be defined as a \>10% increase in dP/dtmax.
Time frame: about 30 minutes
Clinically significant stroke work
Response will be expressed as a percent change in these measures with anodal biphasic pacing (ABP) as compared with cathodal pacing. A clinically significant hemodynamic response to pacing will be defined as a \>10% increase in stroke work.
Time frame: about 30 minutes
Clinically significant left ventricular end-diastolic pressure (LVEDP)
Response will be expressed as a percent change in these measures with anodal biphasic pacing (ABP) as compared with cathodal pacing. A clinically significant hemodynamic response to pacing will be defined as a \>10% increase in LVEDP.
Time frame: about 30 minutes
Clinically significant diastolic relaxation (tau)
Response will be expressed as a percent change in these measures with anodal biphasic pacing (ABP) as compared with cathodal pacing. A clinically significant hemodynamic response to pacing will be defined as a \>10% increase in tau.
Time frame: about 30 minutes
Clinically significant volume measurements
Response will be expressed as a percent change in these measures with anodal biphasic pacing (ABP) as compared with cathodal pacing. A clinically significant hemodynamic response to pacing will be defined as a \>10% increase in volume measurements.
Time frame: about 30 minutes
Capture threshold
This outcome will be measured with decremental pacing threshold testing where pacing output (voltage or pulse width) is decremented until there is a loss of ventricular capture. The minimum output prior to loss of capture is defined as the capture threshold.
Time frame: about 30 minutes
Waveform safety concerns
Defined as the development of any of the following with ABP: ventricular tachycardia \> 3 beats, premature ventricular contractions at frequency greater than baseline, ventricular couplet, significant drop (\>5%) in invasive hemodynamic measures or blood pressure; or any cardioversion for atrial or ventricular arrhythmia.
Time frame: about 30 minutes
Device safety issues
Defined as the occurrence of device related adverse event including: device malfunction, failure to output programmed pulse waveform, or failure to output set voltage
Time frame: about 30 minutes
Procedural safety issues
Defined as the occurrence of procedure related adverse event including: vascular complication, cardiac complication including cardiac perforation, valvular injury, atrioventricular (AV) or bundle branch block, or thromboembolism.
Time frame: about 30 minutes
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