Baroreflex Activation Therapy in Left Ventricular Assist Device Patients Study
- Conditions
- Congestive Heart Failure
- Interventions
- Device: Baroreflex Activation Therapy (BAT)
- Registration Number
- NCT06195046
- Lead Sponsor
- Brian Houston
- Brief Summary
This study will involve LVAD patients who have already received a clinically-indicated BAT (BAROSTIM) device. After recovery from LVAD implant, we will investigate the effects of BAT in a double-blind cross-over study design.
- Detailed Description
Left ventricular assist devices (LVADs) provide a meaningful therapeutic option for patients with end-stage systolic heart failure who cannot receive cardiac transplantation. For these patients, LVADs have been shown to improve mortality, functional capacity, and quality of life \[1-3\]. With ever-improving technological and procedural advances, the number of LVAD implantations for patients with end-stage cardiomyopathy as bridge to transplant, recovery, or even as destination therapy continues to rise \[4\]. Despite the short term clinical benefits of LVAD support, studies show that deleterious neurohormonal activation does not abate after LVAD implantation and that left ventricular scarring (or fibrosis) does not regress and may worsen. Similarly, the prevalence of myocardial recovery with LVAD support has been dismally low with \<1% of patients recovering to the point where their LVAD can be safely explanted. Given that the majority of patients undergoing LVAD are now doing so with a destination therapy designation, and that the median estimated survival time on LVAD support ranges from 4-6 years, the importance of therapies to maximize chances for myocardial recovery while LVAD supported is evident.
The pathophysiologic reasons underlying the lack of abrogation of sympathetic and neurohormonal signaling with LVAD support, even in the face of adequate hemodynamic support, may center around the non-pulsatile nature of the device. Markham and Levine described sympathetic nerve activity in both pulsatile and nonpuslatile LVAD patients in 2013, demonstrating that patients with nonpulsatile devices had markedly elevated muscle sympathetic nerve activity, though pulsatile LVAD patients and normal controls had similar sympathetic activity. In a sequence of experiments, the authors demonstrated that this was at least partly due to baroreceptor unloading in the nonpulsatile patients. Further studies have demonstrated that plasma norepinephrine levels remain elevated after VAD implant, as do neurohormones in the renin-angiotensin-aldosterone axis. Sympathetic neurohormone levels have been shown to correlate with clinical response to LVAD therapy (defined by significant improvement in quality of life determined by the KCCQ), with reduced B-adrenergic receptor kinase-1 and DHPG levels differentiating those with better clinical response. Further, pathologic studies pre- and post-LVAD have demonstrated an acceleration of deleterious myocardial fibrosis during LVAD support, potentially driven by sympathetic and/or RAAS signaling pathways.
As demonstrated in preclinical studies and the clinical BeAT-HF trial, autonomic modulation with baroreflex activation therapy (BAT) with the BAROSTIM NEO system reduced sympathetic signaling, leading to increased NT-proBNP, 6-minute hall walk distance (6MHW), and improved quality of life in patients with chronic systolic heart failure.
However, the role of BAT in the unique physiologic LVAD-supported state has not be characterized. Given the concerns that LVAD support by augment sympathetic and thereby RAAS signaling, and that BAT may abrogate those deleterious pathways, we propose to study the clinical and neurohormonal effects of BAT in LVAD supported patients.
Recruitment & Eligibility
- Status
- RECRUITING
- Sex
- All
- Target Recruitment
- 10
- Age > 18 years
- LVAD patient > 3 months post implant
- Existing BAT device
- Presence of cardiogenic shock, respiratory failure, hypotension or unstable heart failure
- Bradycardia (resting HR <60 beats/minute)
- Presence of suspected pump thrombosis at the time of enrollment
- Presence of any significant ventricular arrhythmias at the time of enrollment
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description control (BAT off) Baroreflex Activation Therapy (BAT) Baroreflex activation therapy turned off for three months treatment (BAT on) Baroreflex Activation Therapy (BAT) Baroreflex activation therapy turned on for three months
- Primary Outcome Measures
Name Time Method 6 Minute Hall Walk 3 months change in distance walked during 6 Minute Hall Walk
- Secondary Outcome Measures
Name Time Method Change in serum renin 3 months, 6 months ng/mL
Change in LVAD system monitor reported flow 3 months, 6 months Liters/minute
Cardiac 123-mIBG scan 3 months, 6 months Heart to mediastinum uptake ratio; Rate of 123-mIBG washout
Change in left ventricular size on transthoracic echocardiogram 3 months, 6 months Centimeters
Change in mitral valve regurgitation severity on transthoracic echocardiogram 3 months, 6 months None, mild, moderate, severe
Change in Serum catecholamines 3 months, 6 months pg/mL
Change in serum aldosterone 3 months, 6 months ng/dL
Minnesota Living with Heart Failure Questionnaire 3 months, 6 months quality of life questionnaire
Change in aortic valve opening frequency on transthoracic echocardiogram 3 months, 6 months Valve opening per beat
Change in right ventricular size on transthoracic echocardiogram 3 months, 6 months Centimeters
Change in Serum norepinephrine 3 months, 6 months pg/mL
Change in serum BNP 3 months, 6 months pg/mL
Change in serum angiotensin 3 months, 6 months U/L
Trial Locations
- Locations (1)
Medical University of South Carolina
🇺🇸Charleston, South Carolina, United States