Ignite Creation Date:
2024-05-06 @ 10:27 AM
Last Modification Date:
2024-10-26 @ 12:30 PM
Study NCT ID:
NCT03261570
Status:
COMPLETED
Last Update Posted:
2022-09-28
First Post:
2017-08-14
Brief Title:
Cardiovagal Baroreflex Deficits Impair Neurovascular Coupling and Cognition in POTS
Sponsor:
New York Medical College
Organization:
New York Medical College
Study Overview
Official Title:
Cardiovagal Baroreflex Deficits Impair Neurovascular Coupling and Cognition in Postural Tachycardia Syndrome
Status:
COMPLETED
Status Verified Date:
2021-08
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
Postural tachycardia syndrome POTS is the chronic form of orthostatic intolerance associated with excessive upright tachycardia and occurs predominantly in young females 85 Among its most troubling symptoms are lightheadedness fatigue and decreased memory often called brain fog by patients Task-related neurovascular coupling NVC links neural activity to an increase in CBF known as functional hyperemia Although memory task performance and NVC deteriorated with angle of tilt in POTS but not healthy controls cerebral blood flow CBF remained similar to control Instead the investigators observed extensive narrow band low frequency 007-013 Hz oscillations in BP OBP that entrained and amplified oscillations in CBF OCBF OBP and OCBF increased with tilt angle and caused impaired working memory and reduced functional hyperemia The cardiovagal baroreflex couples BP to HR to buffer BP changes The investigators hypothesize that the cardiovagal baroreflex becomes progressively impaired with orthostasis in POTS but not in healthy volunteers and accounts for OBP OCBF and loss of NVC further improving the baroreflex reduces OBP OCBF and Brain Fog in POTS
Detailed Description:
Orthostatic intolerance is defined by debilitating upright symptoms that are relieved by sitting or lying Symptoms include upright lightheadedness fatigue confusion and decreased memory called Brain Fog by patients The most common chronic form is Postural Tachycardia Syndrome POTS characterized by excessive upright tachycardia without hypotension Of note 85 of POTS patients are female The proposal that Brain Fog was caused by reduced cerebral blood flow CBF has been disproven because graded incremental upright tilt failed to demonstrate difference in mean CBF compared to healthy volunteers Nevertheless memory task performance deteriorates with angle of tilt as does task-related neurovascular coupling NVC which links neural activity to an increase in CBF known as functional hyperemia The investigators have previously observed that large low frequency 007-013 Hz oscillations in BP OBP which entrained and amplified oscillations in CBF OCBF increased with tilt angle and were associated with impaired working memory and reduced functional hyperemia
The sympathetic baroreflex remains intact and HR is excessively increased in the absence of parasympathetic counterregulation The cardiovagal baroreflex couples BP to HR to buffer BP changes Large low frequency BP oscillations representing a resonance within the sympathetic baroreflex loop occur if there is central hypovolemia an intact sympathetic baroreflex and reduced parasympathetic buffering of BP by HR conditions found in upright POTS This leads to the following hypothetical paradigm
Cardiovagal Baroreflex OBP OCBF NVC working memory Therefore in this application the investigators hypothesize that the cardiovagal baroreflex is impaired in POTS while supine becomes further impaired with orthostasis and accounts for OBP OCBF and loss of NVC Further the investigators propose that improving the cardiovagal baroreflex improves hemodynamics and Brain Fog in POTS patients
The sympathetic baroreflex remains intact and HR is excessively increased in the absence of parasympathetic counterregulation The cardiovagal baroreflex couples BP to HR to buffer BP changes Large low frequency BP oscillations representing a resonance within the sympathetic baroreflex loop occur if there is central hypovolemia an intact sympathetic baroreflex and reduced parasympathetic buffering of BP by HR conditions found in upright POTS This leads to the following hypothetical paradigm
Cardiovagal Baroreflex OBP OCBF NVC working memory Therefore in this application the investigators hypothesize that the cardiovagal baroreflex is impaired in POTS while supine becomes further impaired with orthostasis and accounts for OBP OCBF and loss of NVC Further the investigators propose that improving the cardiovagal baroreflex improves hemodynamics and Brain Fog in POTS patients
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
True
Is a FDA Regulated Device?:
False
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None