1) elucidate the role of the postural CO decrease on cerebral hemodynamics, 2) test the influence of posture, ageing and T2DM on the CO-VO2 relationship. Furthermore, 3) we want to determine the shape of the CO-VO2 relationship.
ID
Source
Brief title
Condition
- Heart failures
- Diabetic complications
- Central nervous system vascular disorders
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The relationship between CO and cerebral hemodynamics in the supine and upright
position.
Secondary outcome
not applicable
Background summary
Despite intact cerebral autoregulation, there is a persistent decrease in
cerebral blood flow (CBF), CBF velocity (CBFV) and cerebral oxygenation (SaO2)
on standing up. We hypothesize that the postural decline in cardiac output (CO)
may be a contributing factor. In healthy exercising man, there is a more or
less linear relationship between CO and oxygen consumption (VO2) with a ~3 L *
min-1 increase in CO for each 1 L * min-1 increase in VO2. It is under debate
whether this relationship is influenced by posture or ageing.
Study objective
1) elucidate the role of the postural CO decrease on cerebral hemodynamics, 2)
test the influence of posture, ageing and T2DM on the CO-VO2 relationship.
Furthermore, 3) we want to determine the shape of the CO-VO2 relationship.
Study design
The study is a cross-over intervention study performed by the Laboratory for
Clinical Cardiovascular Physiology (LCCP) in collaboration with the Dpt. of
Pulmonary Medicine AMC.
In this study, young, aged and T2DM subjects will follow an exercise protocol
in both the supine and upright position. The study consists of an introductory
day and two measurement days, each of approximately 2 hours. Total time of
participation will be about 6 hours. There will be no follow-up whatsoever.
Setting and protocol will be described in detail in section 5 of the protocol
(version 2.0)
Intervention
Incremental cycling exercise with 1-min bouts of constant workload.
Study burden and risks
No risks and benefits are anticipated for the subjects in the study population.
The burden will be two cycling exercise protocols till exhaustion.
Meibergdreef 9
Amsterdam 1105 AZ
NL
Meibergdreef 9
Amsterdam 1105 AZ
NL
Listed location countries
Age
Inclusion criteria
*BMI < 30
reasonable exercise tolerance
(Type-2-diabetes)
Willing and competent to give written incormed consent
Exclusion criteria
*History of: stroke, anemia or polycythemia, known with significant (> 70%) MCA or carotid artery stenosis, clinical manifestation of heart failure or heart disease, clinical manifestation of pulmonary disease, uncontrolled hypertension (BP >160/100 mmHg), orthostatic hypotension, presence of cardiovascular autonomic neuropathy,poor metabolic control (HbA1c > 9.5%), complications of T2DM.
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 | NL41192.018.12 |