Cardiac Resynchronization and MIBG Imaging
Overview
- Phase
- Phase 1
- Intervention
- 123 iodine metaiodobenzylguanidine
- Conditions
- Congestive Heart Failure
- Sponsor
- Mayo Clinic
- Enrollment
- 14
- Locations
- 1
- Primary Endpoint
- Change in 123I-MIBG parameters
- Status
- Terminated
- Last Updated
- 9 years ago
Overview
Brief Summary
Subjects were recruited if their healthcare provider decided that they needed treatment with a special Internal Cardiac Defibrillator (ICD) called a biventricular ICD. The investigators did this study to see if part of the nerve organ, called the sympathetic nervous system, may be responsible for the improvement seen in patients that receive biventricular pacing. The investigators had three ways to measure sympathetic nervous activity: 1) by using a special blood sample, 2) by monitoring heart rhythm, and 3) by performing a special heart scan.
Detailed Description
The Specific Aim #1 of this study is to assess, with 123iodine metaiodobenzylguanidine (123I-MIBG imaging), whether cardiac resynchronization therapy (CRT) rebalances and improves the integrity and function of sympathetic nerve terminals in the failing myocardium. The study will test the hypothesis that resynchronization of biventricular contractility attenuates excessive sympathetic drive, and improves autonomic function and cardiac performance. The Specific Aim #2 of this study is to determine the relationship between 123I-MIBG labeling of sympathetic activity and physiological measures of cardiopulmonary and autonomic function. This aim is to test the hypothesis that impaired cardiac sympathetic activity, determined by 123I-MIBG imaging will be associated with poorer submaximal exercise gas exchange (higher ventilation - carbon dioxide (CO2) slopes, low end tidal CO2, reduced oxygen pulse and a more rapid frequency response) as well as reduced heart rate power spectral frequencies, a blunted response to positional changes and a delayed heart rate recovery.
Investigators
Yong-Mei Cha
MD
Mayo Clinic
Eligibility Criteria
Inclusion Criteria
- Not provided
Exclusion Criteria
- Not provided
Arms & Interventions
Biv-ICD
Subjects will be imaged with 123 iodine metaiodobenzylguanidine.
Intervention: 123 iodine metaiodobenzylguanidine
Outcomes
Primary Outcomes
Change in 123I-MIBG parameters
Time Frame: baseline, 6 months
changes in 123I-MIBG parameters with cardiac performance including LVEF, stroke volume (SV), left ventricle (LV) and left atrium (LA) dimension, distance of 6-minute walk, NYHA class, and ventricular arrhythmic burden
Secondary Outcomes
- Change in submaximal exercise gas exchange(baseline, 6 months)
- Change in Autonomic function(baseline, 6 months)