Autonomic Cardiovascular Control After Heart Transplantation (AccHeart)
The purpose of this prospective study is to investigate denervation (ie. surgical cutting of autonomic nerves) and re-innervation (ie. growth of autonomic nerves) in heart transplant recipients. More specifically, we focus on:
- The physiological consequences of denervation, in particular its consequences for clinical symptoms, orthostatic tolerance (ie. the ability to stand upright) and exercise capacity. We hypothesize that denervation has negative consequences for all these factors.
- The pathological consequences of denervation and reinnervation, in particular its association to acute rejection and coronary artery disease (cardiac allograft vasculopathy, CAV). We hypothesize that reinnervation protects against acute rejection and development of CAV
- Donor and recipient factors associated with the reinnervation process. We hypothesize that characteristics of the surgical procedure (such as aorta cross-clamp time) as well as the rehabilitation process of the recipient (such as physical activity) impacts on the reinnervation process.
Heart Transplant Recipients
|Study Design:||Observational Model: Case Control
Time Perspective: Prospective
|Official Title:||Autonomic Cardiovascular Control After Heart Transplantation|
- Cardiac allograft vasculopathy [ Time Frame: 1 year ]Indications of cardiac allograft vasculopathy (CAV), assessed by intravascular ultrasound (IVUS) during coronary catheterization.
- Acute rejections [ Time Frame: 1 year ]The frequency of acute rejections episodes and time to first rejection (combined time/event outcome), as assessed by analyses of heart biopsy specimens
- Cardiac allograft vasculopathy [ Time Frame: 3 years ]Cf. above
- Acute rejections [ Time Frame: 2 and 3 years ]Cf. above
- Autonomic cardiovascular responses [ Time Frame: 6 months, 1, 2 and 3 years ]Autonomic cardiovascular responses (such as changes in blood pressures, heart rate, cardiac output, total peripheral resistance and heart rate variability) during head-up tilt-test, valsalva maneuver and isometric exercise
- Exercise capacity [ Time Frame: 1, 2 and 3 years ]Cardio-pulmonary responses to a standardized exercise tolerance test (treadmill), such as maximal oxygen consumption(maxVO2), heart rate increase, blood pressure increase, etc.
- Activity recordings [ Time Frame: 6 months, 1, 2 and 3 years ]Number of steps/day during 7 consecutive days, assessed by an accelerometer
- Hormonal levels [ Time Frame: 6 months, 1, 2 and 3 years ]The levels of catecholamines, cortisol and other hormones influenced by autonomic nervous activity in blood, urine and saliva
- General immune activity [ Time Frame: 6 months, 1, 2 and 3 years ]The blood levels of cytokines and other markers of immune function, as well as whole blood gene expression.
- Pain threshold [ Time Frame: 6 months, 1, 2 and 3 years ]Assessment of pain sensitivity by means of an algometer. Anatomically well-defined "trigger-points" are subjected to increasing pressure; the patients alert at the point where the pressure is perceived to be painful
- Clinical symptoms [ Time Frame: 6 months, 1, 2 and 3 years ]Validated questionnaires assessing: symptoms of autonomic dysfunction, quality of life, pain, fatigue, anxiety, depression and sleep problems.
- MetaIodoBenzylGuanidin-scan [ Time Frame: 1 and 3 years ]The degree of sympathetic cardiac reinnervation as assessed by the scintigraphic method MetaIodoBenzylGuanidin-scan
- Echocardiographic indices [ Time Frame: 1, 2 and 3 years ]Echocardiographic indices of cardiac function, such as as systolic and diastolic velocities of the ventricular myocardium based on Tissue Doppler Imaging
- Ambulant blood pressure recording [ Time Frame: 1, 2 and 3 years ]24 hours ambulant blood pressure recordings
- Cardiac catheterization [ Time Frame: 1, 2 and 3 years ]Routine data from surveillance cardiac catheterization procedures, such as pressure recordings, angiograms and biopsy assessments
Biospecimen Retention: Samples With DNA
- Blood samples for analyses of: genomic DNA, RNA-transcription in whole blood, cytokines, cathecholamines, other blood biomarkers
- Urine samples for analyses of: catecholamines, cortisol, other urine biomarkers
- Saliva samples for analyses of: cortisol
- Heart biopsy specimen for analyses of: acute and chronic rejection (routine surveillence procedure)
|Study Start Date:||January 2013|
|Estimated Study Completion Date:||April 2018|
|Primary Completion Date:||March 2016 (Final data collection date for primary outcome measure)|
Heart transplant recipients
Patients receiving orthotopic heart transplant in the enrollment period
Healthy control subjects, having the same age and sex distribution as the heart transplant recipients
Heart transplantation is annually offered to more than 3500 patients worldwide. In Norway, the number is approximately 30/year, and all transplants are carried out at one single hospital (Oslo University Hospital, Rikshospitalet).
Normally, the heart function is intimately controlled by the autonomic nervous system (ANS), but all nervous connections are lost during the surgical transplantation procedure, and the transplanted heart thus becomes denervated. In time, regrowth of nerves may cause partial reinnervation of the new heart.
Some evidence suggests that reinnervation improves exercise capacity and reduces episodes of acute rejections and the development of cardiac allograft vasculopathy. The purpose of this study is further to investigate the changes over time with respect to all parts of the autonomic nervous system (the sympathetic, parasympathetic and sensoric part), and the associated physiological and pathological consequences.
The study may provide knowledge which ultimately could help us improve health and quality of live for heart transplant recipients.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01759966
|Dept. of Cardiology, Oslo University Hospital|
|Oslo, Norway, N-0027|
|Principal Investigator:||Vegard B Wyller, MD,PhD||Oslo University Hospital|