Ignite Creation Date:
2024-05-06 @ 10:22 AM
Last Modification Date:
2024-10-26 @ 12:29 PM
Study NCT ID:
NCT03249272
Status:
TERMINATED
Last Update Posted:
2020-09-16
First Post:
2017-08-08
Brief Title:
Microvascular Dysfunction in Nonischemic Cardiomyopathy Insights From CMR Assessment of Coronary Flow Reserve
Sponsor:
Duke University
Organization:
Duke University
Study Overview
Official Title:
Microvascular Dysfunction in Nonischemic Cardiomyopathy Insights From CMR Assessment of Coronary Flow Reserve
Status:
TERMINATED
Status Verified Date:
2020-08
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Sponsor withdrew funding
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
The aim of this study is to assess microvascular function as determined by a cardiovascular magnetic resonance measurement of whole-heart global perfusion reserve The goal is to determine the prevalence of MVD in two common forms of non-ischemic cardiomyopathy hypertrophic cardiomyopathy HCM and idiopathic dilated cardiomyopathy IDCM The hypothesis that an optimized technique will provide robust detection of MVD and that a multifaceted approach will provide new insights into the pathophysiology of MVD including the influence of myocardial scarring upon the presence and severity of MVD
Detailed Description:
Coronary microvascular dysfunction MVD has been implicated as an important marker of cardiac risk and has been thought to directly contribute to the pathogenesis of a wide variety of cardiomyopathies For instance MVD is believed to cause ischemia with reduction in coronary flow reserve in patients with hypertrophic cardiomyopathy HCM despite the presence of angiographically normal epicardial coronary arteries The implication is that MVD in HCM may lead to the ventricular arrhythmias sudden death and heart failure Similarly patients with idiopathic dilated cardiomyopathy IDCM have blunted coronary flow reserve which appears to be independently associated with poor prognosis
Several etiologic mechanisms have been proposed to explain the occurrence of MVD including structural and functional abnormalities1
1 increased microvascular resistance due to reduced vascular luminal caliber
2 reduced density of microvessels associated with replacement scarring
3 inappropriate vasoconstrictor responses
4 inadequate vasodilator responses
Unfortunately these mechanisms are difficult to study in humans since no technique currently allows the direct visualization of the coronary microcirculation in vivo Thus MVD has been largely studied using non-invasive imaging techniques such as positron emission tomography PET or single photon emitted computed tomography SPECT
Although these methods have provided insight into MVD much remains unknown For example even the prevalence of MVD in patients with various types of cardiomyopathy is unclear with different studies showing widely different rates
Cardiovascular magnetic resonance CMR is increasingly being used in clinical practice to evaluate cardiac disease CMR employs a multifaceted imaging approach with separate techniques used to acquire separate sets of raw data providing information on cardiac morphology function regional myocardial ischemia scarring and global myocardial perfusion reserve The advantage of this approach is that image artifacts in one set of data will not affect the quality of the other datasets and the datasets in combination can be used to distinguish separate pathophysiologies that could confound image interpretation For example perfusion defects could be due to ischemia or scar tissue but since the investigators will obtain both perfusion images and scar images the investigators will be able to resolve the etiology Additionally CMR provides high spatial resolution over 10-fold higher than PET and hence partial volume affects will be kept to a minimum and variability in measurements will be reduced
The aim of this study is to assess microvascular function as determined by a cardiovascular magnetic resonance measurement of whole-heart global perfusion reserve The goal is to determine the prevalence of MVD in two common forms of non-ischemic cardiomyopathy hypertrophic cardiomyopathy HCM and idiopathic dilated cardiomyopathy IDCM The hypothesis that an optimized technique will provide robust detection of MVD and that a multifaceted approach will provide new insights into the pathophysiology of MVD including the influence of myocardial scarring upon the presence and severity of MVD
Several etiologic mechanisms have been proposed to explain the occurrence of MVD including structural and functional abnormalities1
1 increased microvascular resistance due to reduced vascular luminal caliber
2 reduced density of microvessels associated with replacement scarring
3 inappropriate vasoconstrictor responses
4 inadequate vasodilator responses
Unfortunately these mechanisms are difficult to study in humans since no technique currently allows the direct visualization of the coronary microcirculation in vivo Thus MVD has been largely studied using non-invasive imaging techniques such as positron emission tomography PET or single photon emitted computed tomography SPECT
Although these methods have provided insight into MVD much remains unknown For example even the prevalence of MVD in patients with various types of cardiomyopathy is unclear with different studies showing widely different rates
Cardiovascular magnetic resonance CMR is increasingly being used in clinical practice to evaluate cardiac disease CMR employs a multifaceted imaging approach with separate techniques used to acquire separate sets of raw data providing information on cardiac morphology function regional myocardial ischemia scarring and global myocardial perfusion reserve The advantage of this approach is that image artifacts in one set of data will not affect the quality of the other datasets and the datasets in combination can be used to distinguish separate pathophysiologies that could confound image interpretation For example perfusion defects could be due to ischemia or scar tissue but since the investigators will obtain both perfusion images and scar images the investigators will be able to resolve the etiology Additionally CMR provides high spatial resolution over 10-fold higher than PET and hence partial volume affects will be kept to a minimum and variability in measurements will be reduced
The aim of this study is to assess microvascular function as determined by a cardiovascular magnetic resonance measurement of whole-heart global perfusion reserve The goal is to determine the prevalence of MVD in two common forms of non-ischemic cardiomyopathy hypertrophic cardiomyopathy HCM and idiopathic dilated cardiomyopathy IDCM The hypothesis that an optimized technique will provide robust detection of MVD and that a multifaceted approach will provide new insights into the pathophysiology of MVD including the influence of myocardial scarring upon the presence and severity of MVD
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?:
False
Is an FDA AA801 Violation?:
None