The aim of this project is (1) to examine reproducibility of measuring CO and LBF with PC-MRI during supine cycling (phase I) and (2) to measure CO and LBF during supine cycling in patients with CHF and healthy age-matched controls to investigate…
ID
Source
Brief title
Condition
- Heart failures
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
Phase 1: Difference and agreement of blood flow (L/min) in the ascending (CO)
en distal aorta (LBF) measured with PC-MRI in rest en during submaximal
exercise between two days.
Phase 2: Difference of DF (ratio) between patients with CHF and healthy,
age-matched controls.
Secondary outcome
N.A.
Background summary
Patients with chronic heart failure (CHF) suffer from exercise intolerance.
Several studies showed that reduced leg blood flow (LBF) to exercising muscles
during daily activity is an important determinant of reduced exercise capacity.
Theoretically, LBF is determined by two main factors: cardiac output (CO) and
the distribution of blood to exercising muscles. It is evident that patients
with CHF have a reduced cardiac output during exercise as compared to healthy
subjects. In addition, the fraction of blood flow distributed to exercising
muscles (distribution factor - DF) during exercise may be reduced due to an
enhanced activity of the sympathic nervous system, changes in humoral factors,
mechanical factors and inflammatory factors. To what extent the DF is causing
the diminished LBF - and thereby is causing a reduced exercise capacity - is
unknown.
Phase contrast MRI (PC-MRI) is a proven technique to measure blood flow in
large arteries. Different studies also have shown that PC-MRI has the
capability of measuring blood flow in the aorta during exercise at different
levels. However, these studies did only measure the inter-rater reliability and
never measure the day-to-day reproducability.
If PC-MRI has the opportunity to reliable measure blood flow in the ascending
and distal aorta (as a measurement of CO and LBF respectively) it would give a
better understanding to what extent the CO and DF is responsible for the
reduction of LBF. It would increase knowledge of the pathophysiology and
consequently offers opportunities to tailor treatment and prevent unnecessary
interventions. Therefore a technique to measure CO and LBF noninvasively could
be a valuable tool in future clinical practice to individualize treatment.
Study objective
The aim of this project is (1) to examine reproducibility of measuring CO and
LBF with PC-MRI during supine cycling (phase I) and (2) to measure CO and LBF
during supine cycling in patients with CHF and healthy age-matched controls to
investigate the relative contribution of cardiac function (CO) and impaired
blood flow distribution (DF) in LBF (phase II).
Study design
prospective observational design without invasive measurements.
Study burden and risks
No adverse effects of symptom limited exercise testing performed by CHF
patients or healthy controls have been reported in literature, nor in our
clinical experience. With the inclusion of electrocardiographic analysis and
blood pressure measurements during this exercise test, subjects with myocardial
ischaemia and ventricular arrhythmias can be identified and excluded.
Also no adverse effects have been reported in literature for supine exercise
testing which we will apply for MRI measurements. PC-MRI is a non-invasive
measurement and places no additional burden on the subjects. Subjects with
claustrophobia will be excluded at the start of the study.
De Run 4600
Veldhoven 5504DB
NL
De Run 4600
Veldhoven 5504DB
NL
Listed location countries
Age
Inclusion criteria
Phase 1: Healthy volunteers in the age of 18-50 years that are able to perform maximal exercise test.
Phase 2: Patients with systolic heart failure (dilating or ischemic), NYHA-class II/III and ejection fraction <40%.
Exclusion criteria
Phase 1: Cardiovascular disease and Orthopaedic, pulmonary, neuromuscular and other diseases limiting exercise capacity. Claustrophobia.
Phase 2: Recent myocardial infarction (< 3 months), decompensated heart failure, ventricular tachycardia or myocardial ischemia during exercise.
Orthopaedic, vascular, pulmonary, neuromuscular and other disease
limiting exercise capacity in a way that performing exercise tests is not feasible.
Claustrophobia.
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL59443.015.16 |
| Other | VOLGT |