Ignite Creation Date:
2024-05-06 @ 3:37 AM
Last Modification Date:
2024-10-26 @ 11:36 AM
Study NCT ID:
NCT02332564
Status:
COMPLETED
Last Update Posted:
2023-02-14
First Post:
2015-01-05
Brief Title:
Coronary Steal Via Natural Internal Mammary Artery-To-Coronary Artery Bypasses
Sponsor:
Insel Gruppe AG University Hospital Bern
Organization:
Insel Gruppe AG University Hospital Bern
Study Overview
Official Title:
Coronary Steal Via Natural Internal Mammary Artery-To-Coronary Artery Bypasses
Status:
COMPLETED
Status Verified Date:
2023-02
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:
CIMA
Brief Summary:
CORONARY ARTERY DISEASE AND THE BENEFIT OF BYPASSES
Despite considerable advances in medicine cardiovascular diseases remain the number one cause of death globally In industrialized countries coronary artery disease CAD is the leading cause of death consequence of myocardial infarction MI Artificial - or natural - bypasses exert a protective effect by providing an alternative source of blood flow to a myocardial territory potentially affected by an acute coronary occlusion Coronary collaterals represent pre-existing inter-arterial anastomoses and as such are the natural counter-part of surgically created bypasses In patients with chronic CAD sufficient coronary collaterals have been shown to confer a significant benefits in terms of overall mortality and cardiovascular events
EXTRACARDIAC-TO-CORONARY COLLATERAL SUPPLY
Commonly coronary collaterals are implicitly understood to exist between coronary artery branches However the structural existence of coronary collaterals with an extracardiac connection has been confirmed by anatomical investigations Pathophysiologically and with regard to a potential for arteriogenic stimulation the connections from the internal mammary arteries are of special interest
In a recently published work the investigators have investigated the effect of temporary balloon occlusion of the distal IMA on coronary collateral function There were equivocal findings for the left circumflex coronary artery CFI was increased by ipsilateral IMA occlusion but the level of myocardial ischemia was unchanged
MYOCARDIAL STEAL VIA INTERNAL MAMMARY ARTERIES
In the investigators previous study the coronary occlusion with simultaneous distal IMA occlusion was always performed first as a conservative measure against false-positive detection of internal-mammary-to-coronary artery connections Repetitive coronary occlusions per se result in higher collateral flow by collateral recruitment and reduced ischemia by ischemic preconditioning and augmented collateral function Conversely the sensitivity of the employed method was reduced and might have contributed to the equivocal findings in case of the left circumflex artery Moreover the hypothesize d mechanism of localized pressure augmentation was not investigated
This study aims to further characterize the prevalence and function of natural ipsilateral IMA-to-coronary connections as well as to investigate the hemodynamic mechanisms of coronary collateral function augmentation by distal IMA occlusion In the investigators last study the increased coronary collateral function in response to manipulation of a potential coronary collateral donor in this case the IMA was taken as indirect evidence for the existence of IMA-to-coronary-artery connections Thus the employed distal IMA occlusion served as a positive stimulus Conceptually additional evaluation with a negative stimulus could heighten the discriminatory power of the investigation This could be in the form of a hyperemic stimulus affecting the collateral donor ie in analogy to myocardial or coronary steal ie a reduction in coronary collateral supply to a collateral recipient
Despite considerable advances in medicine cardiovascular diseases remain the number one cause of death globally In industrialized countries coronary artery disease CAD is the leading cause of death consequence of myocardial infarction MI Artificial - or natural - bypasses exert a protective effect by providing an alternative source of blood flow to a myocardial territory potentially affected by an acute coronary occlusion Coronary collaterals represent pre-existing inter-arterial anastomoses and as such are the natural counter-part of surgically created bypasses In patients with chronic CAD sufficient coronary collaterals have been shown to confer a significant benefits in terms of overall mortality and cardiovascular events
EXTRACARDIAC-TO-CORONARY COLLATERAL SUPPLY
Commonly coronary collaterals are implicitly understood to exist between coronary artery branches However the structural existence of coronary collaterals with an extracardiac connection has been confirmed by anatomical investigations Pathophysiologically and with regard to a potential for arteriogenic stimulation the connections from the internal mammary arteries are of special interest
In a recently published work the investigators have investigated the effect of temporary balloon occlusion of the distal IMA on coronary collateral function There were equivocal findings for the left circumflex coronary artery CFI was increased by ipsilateral IMA occlusion but the level of myocardial ischemia was unchanged
MYOCARDIAL STEAL VIA INTERNAL MAMMARY ARTERIES
In the investigators previous study the coronary occlusion with simultaneous distal IMA occlusion was always performed first as a conservative measure against false-positive detection of internal-mammary-to-coronary artery connections Repetitive coronary occlusions per se result in higher collateral flow by collateral recruitment and reduced ischemia by ischemic preconditioning and augmented collateral function Conversely the sensitivity of the employed method was reduced and might have contributed to the equivocal findings in case of the left circumflex artery Moreover the hypothesize d mechanism of localized pressure augmentation was not investigated
This study aims to further characterize the prevalence and function of natural ipsilateral IMA-to-coronary connections as well as to investigate the hemodynamic mechanisms of coronary collateral function augmentation by distal IMA occlusion In the investigators last study the increased coronary collateral function in response to manipulation of a potential coronary collateral donor in this case the IMA was taken as indirect evidence for the existence of IMA-to-coronary-artery connections Thus the employed distal IMA occlusion served as a positive stimulus Conceptually additional evaluation with a negative stimulus could heighten the discriminatory power of the investigation This could be in the form of a hyperemic stimulus affecting the collateral donor ie in analogy to myocardial or coronary steal ie a reduction in coronary collateral supply to a collateral recipient
Detailed Description:
CORONARY ARTERY DISEASE AND THE BENEFIT OF BYPASSES
Despite considerable advances in medicine cardiovascular diseases remain the number one cause of death globally In industrialized countries coronary artery disease CAD is the leading cause of death consequence of myocardial infarction MI
In patients with acute coronary syndrome percutaneous coronary intervention PCI has been shown to improve outcomes2 However in stable CAD PCI has not been demonstrated to reduce the incidence of myocardial infarction or death Coronary artery bypass grafting CABG was superior to PCI in patients with diabetes and multivessel coronary artery disease CABG significantly reduced rates of death and myocardial infarction compared to PCI but with a higher rate of stroke Furthermore in patients with advanced coronary artery disease rates of myocardial infarction were more than 60 lower with CABG compared to PCI
Conceptually the benefit of CABG over PCI is not surprising as PCI targets significant coronary lesions thought to be responsible for causing ischemia However the deleterious effects of atherosclerosis are not typically preceded by significant luminal vascular narrowing The vulnerable plaque eventually becoming the culprit plaque causing myocardial infarction or sudden cardiac death is typically relatively nonstenotic Furthermore due to being multifocal and widespread plaque vulnerability is not a target for nor amenable to PCI
Conversely artificial - or natural - bypasses exert a protective effect by providing an alternative source of blood flow to a myocardial territory potentially affected by an acute coronary occlusion Coronary collaterals represent pre-existing inter-arterial anastomoses and as such are the natural counter-part of surgically created bypasses In patients with chronic CAD sufficient coronary collaterals have been shown to confer a significant benefits in terms of overall mortality and cardiovascular events
EXTRACARDIAC-TO-CORONARY COLLATERAL SUPPLY
Commonly coronary collaterals are implicitly understood to exist between coronary artery branches However the structural existence of coronary collaterals with an extracardiac connection has been confirmed by anatomical investigations Pathophysiologically and with regard to a potential for arteriogenic stimulation the connections from the internal mammary arteries are of special interest Indeed before the advent of coronary bypass surgery several clinical studies examined the usefulness of a minimally invasive surgery to augment collateral flow to the heart via these internal-mammary-to-coronary-artery connections in patients with angina pectoris The performed distal bilateral ligation of the internal mammary arteries was thought to improve flow over naturally pre-existing anastomoses between the internal mammary arteries and the coronary circulation
In a recently published work the investigators have investigated the effect of temporary balloon occlusion of the distal IMA on coronary collateral function 180 pairs of measurements were performed in 120 patients electively referred for coronary angiography Levels of collateral function and myocardial ischemia were determined during two coronary balloon occlusions the first with the second without distal IMA balloon occlusion Coronary collateral function determined by collateral flow index CFI was consistently increased by ipsilateral but not contralateral IMA balloon occlusion in the left anterior descending LAD coronary artery and the right coronary artery RCA Furthermore these findings were corroborated by the observed reduction in ischemia as assessed by the sensitive tool of intracoronary ECG However there were equivocal findings for the left circumflex coronary artery CFI was increased by ipsilateral IMA occlusion but the level of myocardial ischemia was unchanged
MYOCARDIAL STEAL VIA INTERNAL MAMMARY ARTERIES
In the investigators previous study the coronary occlusion with simultaneous distal IMA occlusion was always performed first as a conservative measure against false-positive detection of internal-mammary-to-coronary artery connections Repetitive coronary occlusions per se result in higher collateral flow by collateral recruitment and reduced ischemia by ischemic preconditioning and augmented collateral function Conversely the sensitivity of the employed method was reduced and might have contributed to the equivocal findings in case of the left circumflex artery Moreover the hypothesize d mechanism of localized pressure augmentation was not investigated
This study aims to further characterize the prevalence and function of natural ipsilateral IMA-to-coronary connections as well as to investigate the hemodynamic mechanisms of coronary collateral function augmentation by distal IMA occlusion In the investigators last study the increased coronary collateral function in response to manipulation of a potential coronary collateral donor in this case the IMA was taken as indirect evidence for the existence of IMA-to-coronary-artery connections Thus the employed distal IMA occlusion served as a positive stimulus Conceptually additional evaluation with a negative stimulus could heighten the discriminatory power of the investigation This could be in the form of a hyperemic stimulus affecting the collateral donor ie in analogy to myocardial or coronary steal ie a reduction in coronary collateral supply to a collateral recipient
Despite considerable advances in medicine cardiovascular diseases remain the number one cause of death globally In industrialized countries coronary artery disease CAD is the leading cause of death consequence of myocardial infarction MI
In patients with acute coronary syndrome percutaneous coronary intervention PCI has been shown to improve outcomes2 However in stable CAD PCI has not been demonstrated to reduce the incidence of myocardial infarction or death Coronary artery bypass grafting CABG was superior to PCI in patients with diabetes and multivessel coronary artery disease CABG significantly reduced rates of death and myocardial infarction compared to PCI but with a higher rate of stroke Furthermore in patients with advanced coronary artery disease rates of myocardial infarction were more than 60 lower with CABG compared to PCI
Conceptually the benefit of CABG over PCI is not surprising as PCI targets significant coronary lesions thought to be responsible for causing ischemia However the deleterious effects of atherosclerosis are not typically preceded by significant luminal vascular narrowing The vulnerable plaque eventually becoming the culprit plaque causing myocardial infarction or sudden cardiac death is typically relatively nonstenotic Furthermore due to being multifocal and widespread plaque vulnerability is not a target for nor amenable to PCI
Conversely artificial - or natural - bypasses exert a protective effect by providing an alternative source of blood flow to a myocardial territory potentially affected by an acute coronary occlusion Coronary collaterals represent pre-existing inter-arterial anastomoses and as such are the natural counter-part of surgically created bypasses In patients with chronic CAD sufficient coronary collaterals have been shown to confer a significant benefits in terms of overall mortality and cardiovascular events
EXTRACARDIAC-TO-CORONARY COLLATERAL SUPPLY
Commonly coronary collaterals are implicitly understood to exist between coronary artery branches However the structural existence of coronary collaterals with an extracardiac connection has been confirmed by anatomical investigations Pathophysiologically and with regard to a potential for arteriogenic stimulation the connections from the internal mammary arteries are of special interest Indeed before the advent of coronary bypass surgery several clinical studies examined the usefulness of a minimally invasive surgery to augment collateral flow to the heart via these internal-mammary-to-coronary-artery connections in patients with angina pectoris The performed distal bilateral ligation of the internal mammary arteries was thought to improve flow over naturally pre-existing anastomoses between the internal mammary arteries and the coronary circulation
In a recently published work the investigators have investigated the effect of temporary balloon occlusion of the distal IMA on coronary collateral function 180 pairs of measurements were performed in 120 patients electively referred for coronary angiography Levels of collateral function and myocardial ischemia were determined during two coronary balloon occlusions the first with the second without distal IMA balloon occlusion Coronary collateral function determined by collateral flow index CFI was consistently increased by ipsilateral but not contralateral IMA balloon occlusion in the left anterior descending LAD coronary artery and the right coronary artery RCA Furthermore these findings were corroborated by the observed reduction in ischemia as assessed by the sensitive tool of intracoronary ECG However there were equivocal findings for the left circumflex coronary artery CFI was increased by ipsilateral IMA occlusion but the level of myocardial ischemia was unchanged
MYOCARDIAL STEAL VIA INTERNAL MAMMARY ARTERIES
In the investigators previous study the coronary occlusion with simultaneous distal IMA occlusion was always performed first as a conservative measure against false-positive detection of internal-mammary-to-coronary artery connections Repetitive coronary occlusions per se result in higher collateral flow by collateral recruitment and reduced ischemia by ischemic preconditioning and augmented collateral function Conversely the sensitivity of the employed method was reduced and might have contributed to the equivocal findings in case of the left circumflex artery Moreover the hypothesize d mechanism of localized pressure augmentation was not investigated
This study aims to further characterize the prevalence and function of natural ipsilateral IMA-to-coronary connections as well as to investigate the hemodynamic mechanisms of coronary collateral function augmentation by distal IMA occlusion In the investigators last study the increased coronary collateral function in response to manipulation of a potential coronary collateral donor in this case the IMA was taken as indirect evidence for the existence of IMA-to-coronary-artery connections Thus the employed distal IMA occlusion served as a positive stimulus Conceptually additional evaluation with a negative stimulus could heighten the discriminatory power of the investigation This could be in the form of a hyperemic stimulus affecting the collateral donor ie in analogy to myocardial or coronary steal ie a reduction in coronary collateral supply to a collateral recipient
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| 2631 | OTHER | Bern University Hospital | None |