Coronary artery fistula: Difference between revisions

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{{Coronary angiography2}}
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{{CMG}}; '''Associate Editor-in-Chief:''' Leida Perez, M.D.
  Caption        = |
  DiseasesDB    = |
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{{SI}}
{{WikiDoc Cardiology Network Infobox}}
{{CMG}}


'''Associate Editor-in-Chief:''' [[User:KeriShafer|Keri Shafer, M.D.]] [mailto:kshafer@bidmc.harvard.edu]
{{SK}} CAF, CAVF


{{Editor Join}}
== Overview ==
A coronary artery fistula is any abnormal communication through which [[coronary artery]] [[blood]] is shunted into a [[cardiac]] chamber, great vessel, or other [[vascular]] structure without first passing through the [[myocardial]] [[capillary bed]]. The number, origin, and course of the [[coronary arteries]] is otherwise normal.
 
== Anatomy ==
The [[coronary artery fistula]] can terminate in:
#Any of the [[cardiac chambers]]
#The [[vessels of Wearn]] that empty into the [[cardiac chambers]]
#The [[coronary sinus]]
#The [[SVC]]
#The [[pulmonary veins]]
#The [[mediastinal]] vessels


== Overview ==
Incidental [[fistulas]] are more likely to be multiple. If the [[coronary artery fistula]] is originated from the [[left coronary artery]], is less likely to terminate in the [[RV]].
Coronary artery fistula is any abnormal communication through which [[coronary artery]] [[blood]] is shunted into a [[cardiac]] chamber, great vessel, or other [[vascular]] structure without first passing through the [[myocardial]] [[capillary bed]]. The number, origin, and course of the [[arteries]] is otherwise normal.  


About 25% of [[fistulas]] are not associated with any other type of [[anomaly]]. The most common associated [[congenital anomaly]] is pulmonic or [[aortic valve]] [[atresia]] with or without a [[VSD]].
[[Symptomatic]] [[fistulas]] from case reports are more likely to be single, require [[surgery]], cause [[chest pain]], result in a continuous [[murmur]], and drain into the [[RA]] or [[RV]].
== Epidemiology and Demographics ==


The incidence in angiographic studies is .08% to .3% (usually an incidental finding at the time of angiography for another problem), but is important to know that the total incidence is unclear because many coronary artery fistulas are small and undetected in life. It is often still a postmortem diagnosis, in which 15% of coronary anomalies are coronary artery fistulas.
[[Fistulas]] may enter as a single vessel or as a [[plexus]] with multiple small entry sites, the fistulous opening may occur at the end of a main vessel or one of its branches or in the middle of the vessel forming a side-to-side [[anastomosis]].


== Anatomy ==
Progressive dilatation of the fistulous connection can occur due to the effect of increasing flow through the vessel over time, rather than a defect in the vessel wall.


The coronary artery fistula can terminate in:
==Pathophysiology ==
#Any of the cardiac chambers
#Thebesian veins that empty into the cardiac chambers
#The coronary sinus
#The SVC
#The pulmonary veins
#The mediastinal vessels


Incidental fistulas are more likely to be multiple. If the coronary artery fistula is originated from the left coronary artery, is less likely to terminate in the RV.
When the [[coronary]] [[fistula]] connects to a right-sided chamber or vessel ([[RA]], [[RV]], or [[PA]]), there is a [[left-to-right shunt]] with increased flow delivered to the [[pulmonary circulation]] and ultimately to the left [[heart]].


Symptomatic fistulas from case reports are more likely to be single, require surgery, cause chest pain, result in a continuous murmur, and drain into the RA or RV.
The [[left-to-right shunt]] is usually small with a 1.5:1 ratio, not infrequently the magnitude of the shunt is so small as to not be quantifiable by [[oximetry]], [[Cardiac output#Dilution methods|indicator dilution methods]] etc.


Fistulas may enter as a single vessel or as a plexus with multiple small entry sites, the fistulous opening may occur at the end of a main vessel or one of its branches or in the middle of the vessel forming a side-to-side anastomosis.
Large [[fistulas]] draining into the [[LA]] or the [[LV]] can cause volume overload similar to that caused by [[aortic insufficiency]].


Progressive dilatation of the fistulous connection can occur due to the effect of increasing flow through the vessel over time, rather than a defect in the vessel wall.
Patients with [[coronary artery fistulas]] can experience [[myocardial infarction]] in the absence of other [[coronary artery]] [[pathology]]. This can because the [[fistula]] competes for flow with the normal [[circulation]].


== Etiology & Pathophysiology ==
Since the [[coronary circulation]] often has a higher resistance to flow there can be [[Cardiac steal syndrome|coronary steal]], and effect can be visualized on [[thallium]] scanning.


Most coronary artery fistulas are congenital in origin. They occur at week 6 to 8 as a result of a defect in the coalescence of endothelial lined blood islands.
Using [[electromagnetic]] flow probes, studies have shown a 2.5 fold increase in flow to the [[distal]] [[vessel]] when the [[fistula]] is [[Occlusion|occluded]].


Acquired coronary artery fistulas are rare. They are caused by:
Symptoms and the [[scintigraphic]] abnormality may disappear with [[ligation]].


# Gunshot wounds and shrapnel
==Causes==
# Stab wounds
===Congenital===
# Inadvertent placement of an SVG graft to a coronary vein
Approximately 75% of [[coronary artery fistulas]] are [[congenital]] in origin. They develop at week 6 to 8 as a result of a defect in the coalescence of [[endothelial]] lined [[blood islands]].
# Secondary to large atherosclerotic coronary aneurysms
# As a complication of acute MI
# Repeated endomyocardial biopsies in transplant patients with a fistula to the RV.


When the coronary fistula connects to a right-sided chamber or vessel (RA, RV, or PA), there is a left-to-right shunt with increased flow delivered to the pulmonary circulation and ultimately to the left heart.
===Acquired===
[[Acquired]] [[coronary artery fistulas]] occur in 25% of cases. They are caused by:


The left-to-right shunt is usually small with a 1.5:1 ratio, not infrequently the magnitude of the shunt is so small as to not be quantifiable by oximetry, indicator dilution methods etc.
#Gunshot [[wounds]] and [[shrapnel]]
#Stab [[wounds]]
#Inadvertent placement of an [[SVG]] graft to a [[coronary vein]]
#Secondary to large [[atherosclerotic]] [[coronary]] [[aneurysms]]
#As a [[complication]] of [[acute MI]]
#Repeated [[endomyocardial]] [[biopsies]] in transplant patients with a [[fistula]] to the [[RV]].


Large fistulas draining into the LA or the LV can cause volume overload similar to that caused by aortic insufficiency.
== Epidemiology and Demographics ==
The incidence in [[angiographic]] studies is .08% to .3% (usually an incidental finding at the time of [[angiography]] for another problem), but is important to know that the true incidence is unknown given that many [[coronary artery fistulas]] are small and undetected in life. Coronary artery fistula remains a [[postmortem]] [[diagnosis]], and 15% of [[coronary artery anomalies]] are due to [[coronary artery fistulas]].


Patients with coronary artery fistulas can experience myocardial infarction in the absence of other coronary artery pathology. This can because the fistula competes for flow with the normal circulation.
==Natural History, Complications, Prognosis==


Since the coronary circulation often has a higher resistance to flow there can be coronary steal, and effect can be visualized on thallium scanning.
* Highly variable. Many patients remain [[asymptomatic]], others develop symptoms after a long [[asymptomatic]] period.


Using electromagnetic flow probes, studies have shown a 2.5 fold increase in flow to the distal vessel when the fistula is occluded.
* Spontaneous closure can occur in infancy, but is unusual in adulthood.


Symptoms and the scintigraphic abnormality may disappear with ligation
* Those that are due to [[endomyocardial]] [[biopsy]] have been shown sometimes to close spontaneously.


== Natural History ==
* [[MI]] and [[bacterial endocarditis]] are rare.


* Highly variable. Many patients remain asymptomatic, others develop symptoms after a long asymptomatic period.
In the March 2010 Circulation article titled “Predictors of Long-Term Adverse Outcomes in Patients With Congenital Coronary Artery Fistulae”, Valente et al discuss long-term outcomes of patients with treated and untreated [[coronary artery fistula]] ([[CAF]]) closure. <ref name="pmid20332380">{{cite journal |author=Valente AM, Lock JE, Gauvreau K, ''et al.'' |title=Predictors of Long-Term Adverse Outcomes in Patients With Congenital Coronary Artery Fistulae |journal=Circ Cardiovasc Interv |volume=|issue= |pages= |year=2010 |month=March |pmid=20332380 |doi=10.1161/CIRCINTERVENTIONS.109.883884 |url=}}</ref> Specifically, investigation was directed at whether or not[[clinical]] and [[angiographic]] features associated with [[CAF]] closure ([[symptomatic]] [[heart failure]], [[angina]] and [[myocardial infarction]]) predict [[adverse outcomes]].


* Spontaneous closure can occur in infancy, but is unusual in adulthood.
===Major Complications===
11 patients (15%) experienced [[symptomatic]] [[cardiomyopathy]], [[coronary thrombosis]] and [[MI]].


* Those that are due to endomyocardial biopsy have been shown sometimes to close spontaneously.
===Predictors of adverse outcome===
Both [[angiographic]] and [[clinical]] features were predictive of [[adverse outcome]].
 
#'''[[Angiographic]] predictors'''<br>Drainage of [[CAF]] into the [[coronary sinus]] (P<0.001)<br>
#'''[[Clinical]] predictors'''<br>*[[Hyperlipidemia]] (P<0.001)<br>*Systemic [[hypertension]] (P<0.001)<br>*Older age at [[diagnosis]] (P<0.001)<br>*[[Diabetes]] (P=0.05)<br>*Tobacco use (P=0.006)
 
===Long-term complications===
The investigators conclude that long-term [[complications]] of [[CAF]] closure may include:
*[[Myocardial infarction]] ([[MI]])
*[[Coronary thrombosis]]
*[[Cardiomyopathy]]
 
===Further considerations===
Long-term [[anticoagulation]] is suggested as [[treatment]] for the high-risk [[CAF]] that drain into the [[coronary sinus]]. This [[condition]] is likely to be associated with long-term morbidities after closure.


* MI and bacterial endocarditis are rare.
==Differentiation form other Disorders==
On angiography, a coronary artery fistula must be distinguished from a tumor blush, or arterial blood flow to a [[myxoma]].


== Diagnosis ==  
== Diagnosis ==  


===Symptoms===
===Symptoms===
 
*[[CHF]] occurs in about 20% of these patients, usually with [[fistulas]] draining into the [[RV]] or [[RA]].
* CHF occurs in about 20% of these patients, usually with fistulas draining into the RV or RA.
*Those draining into the left side of the [[heart]] cause [[dyspnea]], [[fatigue]] or [[ischemia]].
* Those draining into the left side of the heart cause dyspnea, fatigue or ischemia.
*There is no good relationship between the size of the [[fistula]] and symptoms.
* There is no good relationship between the size of the fistula and symptoms.


===Physical Examination===
===Physical Examination===


====Heart====
====Heart====
* The most common physical finding is a continuous murmur.  
*The most common physical finding is a continuous [[murmur]].  
* If the fistula is connected to the pulmonary artery, then the murmur will be best heard in the left 2cd or 3rd interspace.
*If the [[fistula]] is connected to the [[pulmonary artery]], then the [[murmur]] will be best heard in the left 2nd or 3rd interspace.
* With fistulas draining into the RA, the murmur is best heard to the right of the sternum.
*With [[fistulas]] draining into the [[RA]], the [[murmur]] is best heard to the right of the [[sternum]].
* Fistulas draining into the RV or LA are best heard at the lower left sternal border or subxyphoid areas. Usually the diastolic component is louder in a fistula to the RV because the decreasing size of the hole during systolic contraction, and the systolic component is louder when connected to the PA or the atria.  
*[[Fistulas]] draining into the [[RV]] or [[LA]] are best heard at the lower left [[sternal]] border or subxyphoid areas. Usually the [[diastolic]] component is louder in a [[fistula]] to the [[RV]] because the decreasing size of the hole during [[systolic]] [[Muscle contraction|contraction]], and the [[systolic]] component is louder when connected to the [[PA]] or the [[atria]].  
* Fistulas to the LV are least likely to cause a murmur.
*[[Fistulas]] to the [[LV]] are least likely to cause a [[murmur]].


== Laboratory Findings ==  
== Laboratory Findings ==  
Line 109: Line 114:


=== Chest X Ray ===
=== Chest X Ray ===
*Chest x-ray may show cardiomegaly and increased pulmonary vasculature.
*[[Chest x-ray]] may show [[cardiomegaly]] and increased [[pulmonary]] [[vasculature]].


=== Echocardiography or Ultrasound ===
=== Echocardiography or Ultrasound ===


* A coronary artery fistula can be visualized on ECHO as an enlarged lumen arising from the aortic root or in a more distal location, with continuous or turbulent flow. Angiographic confirmation is usually necessary.
* A [[coronary artery fistula]] can be visualized on [[ECHO]] as an enlarged [[lumen]] arising from the [[aortic root]] or in a more [[distal]] location, with continuous or [[turbulent flow]]. [[Angiographic]] confirmation is usually necessary.


== Treatment ==
== Treatment ==
Line 120: Line 125:


==== Indications for Surgery ====
==== Indications for Surgery ====
*Surgery is necessary for the management of symptomatic fistulas. Murmurs are more frequent in those with symptoms and in those who ultimately require surgery.
*[[Surgery]] is necessary for the management of [[symptomatic]] [[fistulas]]. [[Murmurs]] are more frequent in those with symptoms and in those who ultimately require [[surgery]].


==== Surgical Outcomes ====
==== Surgical Outcomes ====
*Mortality rate of 0-1.7% in surgical series.
*[[Mortality rate]] of 0-1.7% in [[surgical]] series.


*Most have an improvement in symptoms postoperatively.
*Most have an improvement in symptoms postoperatively.


==Recent Research==
In the March 2010 Circulation article titled “Predictors of Long-Term Adverse Outcomes in Patients With Congenital Coronary Artery Fistulae”, Valente et al discuss long-term outcomes of patients with treated and untreated [[coronary artery fistula]] ([[CAF]]) closure. <ref name="pmid20332380">{{cite journal |author=Valente AM, Lock JE, Gauvreau K, ''et al.'' |title=Predictors of Long-Term Adverse Outcomes in Patients With Congenital Coronary Artery Fistulae |journal=Circ Cardiovasc Interv |volume= |issue= |pages= |year=2010 |month=March |pmid=20332380 |doi=10.1161/CIRCINTERVENTIONS.109.883884 |url=}}</ref> Specifically, investigation was directed at whether or not [[clinical]] and [[angiographic]] features associated with [[CAF]] closure ([[symptomatic]] [[heart failure]], [[angina]] and [[myocardial infarction]]) predict adverse outcomes.
===Data===
76 [[CAF]] patients who underwent [[diagnostic]] [[cardiac catheterization]] at Children’s Hospital Boston from 1959-2008 were studied. 20% of these patients suffered additional [[congenital heart disease]].
64 patients underwent [[surgical]] closure (44 witnessed transcatheter closure and 20 underwent [[surgical]] repair). 3 of these patients underwent a second intervention (repeat [[surgery]] was performed on 1 of the patients and 2 patients underwent a second transcatheter closure). 1 of the 44 transcatheter closure patients went in for a repeat procedure for residual [[fistula]].
12 patients experienced no intervention.
===Major Complications===
11 patients (15%) experienced [[symptomatic]] [[cardiomyopathy]], [[coronary thrombosis]] and [[MI]].
===Predictors of adverse outcome===
Both [[angiographic]] and [[clinical]] features were predictive of [[adverse outcome]].


#'''[[Angiographic]] predictors'''<br>Drainage of [[CAF]] into the [[coronary sinus]] (P<0.001)<br>
==2008 ACC/AHA Guidelines for the Management of Adults With Congenital Heart Disease (DO NOT EDIT)<ref name="pmid19038677">{{cite journal| author=Warnes CA, Williams RG, Bashore TM, Child JS, Connolly HM, Dearani JA et al.| title=ACC/AHA 2008 guidelines for the management of adults with congenital heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Develop Guidelines on the Management of Adults With Congenital Heart Disease). Developed in Collaboration With the American Society of Echocardiography, Heart Rhythm Society, International Society for Adult Congenital Heart Disease, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. | journal=J Am Coll Cardiol | year= 2008 | volume= 52 | issue= 23 | pages= e1-121 | pmid=19038677 | doi=10.1016/j.jacc.2008.10.001 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19038677  }} </ref>==
#'''[[Clinical]] predictors'''<br>*[[Hyperlipidemia]] (P<0.001)<br>*Systemic [[hypertension]] (P<0.001)<br>*Older age at [[diagnosis]] (P<0.001)<br>*[[Diabetes]] (P=0.05)<br>*Tobacco use (P=0.006)
===Coronary Arteriovenous Fistula (DO NOT EDIT)<ref name="pmid19038677">{{cite journal| author=Warnes CA, Williams RG, Bashore TM, Child JS, Connolly HM, Dearani JA et al.| title=ACC/AHA 2008 guidelines for the management of adults with congenital heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Develop Guidelines on the Management of Adults With Congenital Heart Disease). Developed in Collaboration With the American Society of Echocardiography, Heart Rhythm Society, International Society for Adult Congenital Heart Disease, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. | journal=J Am Coll Cardiol | year= 2008 | volume= 52 | issue= 23 | pages= e1-121 | pmid=19038677 |doi=10.1016/j.jacc.2008.10.001 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19038677 }} </ref>===
 
{|class="wikitable"
===Long-term complications===
|-
The investigators conclude that long-term [[complications]] of [[CAF]] closure may include:
| colspan="1" style="text-align:center; background:LightGreen"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class I]]
*[[Myocardial infarction]] ([[MI]])
|-
*[[Coronary thrombosis]]
| bgcolor="LightGreen"|<nowiki>"</nowiki>'''1.''' If a continuous murmur is present, its origin should be defined either by [[echocardiography]], [[MRI]], [[CT]][[angiography]], or cardiac catheterization. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
*[[Cardiomyopathy]]
|-
 
| bgcolor="LightGreen"|<nowiki>”</nowiki>'''2.''' A large coronary [[arteriovenous fistula]] (CAVF), regardless of symptomatology, should be closed via either a transcatheter or surgical route after delineation of its course and its potential to fully obliterate the fistula. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
===Further considerations===
|-
Long-term [[anticoagulation]] is suggested as [[treatment]] for the high-risk [[CAF]] that drain into the [[coronary sinus]]. This [[condition]] is likely to be associated with long-term morbidities after closure.
| bgcolor="LightGreen"|<nowiki>”</nowiki>'''3.''' A small to moderate CAVF in the presence of documented [[myocardial ischemia]], [[arrhythmia]], otherwise unexplained ventricular systolic or diastolic dysfunction or enlargement, or endarteritis should be closed via either a transcatheter or surgical approach after delineation of its course and its potential to fully obliterate the fistula. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
 
|}
== Acknowledgements ==
{|class="wikitable"
The content on this page was first contributed by Dr. Leida Perez
|-
| colspan="1" style="text-align:center; background:LightCoral"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class III]]
|-
| bgcolor="LightCoral"|<nowiki>"</nowiki>'''1.''' Patients with small, asymptomatic CAVF should not undergo closure of CAVF. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
|}
{|class="wikitable"
|-
| colspan="1" style="text-align:center; background:LemonChiffon"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class IIa]]
|-
| bgcolor="LemonChiffon"|<nowiki>"</nowiki>'''1.''' Clinical follow-up with [[echocardiography]] every 3 to 5 years can be useful for patients with small, asymptomatic CAVF to exclude development of symptoms or [[arrhythmia]]s or progression of size or chamber enlargement that might alter management. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''<nowiki>"</nowiki>
|}


==References==
==References==
{{reflist}}  
{{reflist|2}}


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{{Congenital malformations and deformations of circulatory system}}
{{SIB}}
{{Coronary Angiography}}
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[[Category:Congenital heart disease]]


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Latest revision as of 19:09, 5 May 2014

Coronary Angiography

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor-in-Chief: Leida Perez, M.D.

Synonyms and keywords: CAF, CAVF

Overview

A coronary artery fistula is any abnormal communication through which coronary artery blood is shunted into a cardiac chamber, great vessel, or other vascular structure without first passing through the myocardial capillary bed. The number, origin, and course of the coronary arteries is otherwise normal.

Anatomy

The coronary artery fistula can terminate in:

  1. Any of the cardiac chambers
  2. The vessels of Wearn that empty into the cardiac chambers
  3. The coronary sinus
  4. The SVC
  5. The pulmonary veins
  6. The mediastinal vessels

Incidental fistulas are more likely to be multiple. If the coronary artery fistula is originated from the left coronary artery, is less likely to terminate in the RV.

Symptomatic fistulas from case reports are more likely to be single, require surgery, cause chest pain, result in a continuous murmur, and drain into the RA or RV.

Fistulas may enter as a single vessel or as a plexus with multiple small entry sites, the fistulous opening may occur at the end of a main vessel or one of its branches or in the middle of the vessel forming a side-to-side anastomosis.

Progressive dilatation of the fistulous connection can occur due to the effect of increasing flow through the vessel over time, rather than a defect in the vessel wall.

Pathophysiology

When the coronary fistula connects to a right-sided chamber or vessel (RA, RV, or PA), there is a left-to-right shunt with increased flow delivered to the pulmonary circulation and ultimately to the left heart.

The left-to-right shunt is usually small with a 1.5:1 ratio, not infrequently the magnitude of the shunt is so small as to not be quantifiable by oximetry, indicator dilution methods etc.

Large fistulas draining into the LA or the LV can cause volume overload similar to that caused by aortic insufficiency.

Patients with coronary artery fistulas can experience myocardial infarction in the absence of other coronary artery pathology. This can because the fistula competes for flow with the normal circulation.

Since the coronary circulation often has a higher resistance to flow there can be coronary steal, and effect can be visualized on thallium scanning.

Using electromagnetic flow probes, studies have shown a 2.5 fold increase in flow to the distal vessel when the fistula is occluded.

Symptoms and the scintigraphic abnormality may disappear with ligation.

Causes

Congenital

Approximately 75% of coronary artery fistulas are congenital in origin. They develop at week 6 to 8 as a result of a defect in the coalescence of endothelial lined blood islands.

Acquired

Acquired coronary artery fistulas occur in 25% of cases. They are caused by:

  1. Gunshot wounds and shrapnel
  2. Stab wounds
  3. Inadvertent placement of an SVG graft to a coronary vein
  4. Secondary to large atherosclerotic coronary aneurysms
  5. As a complication of acute MI
  6. Repeated endomyocardial biopsies in transplant patients with a fistula to the RV.

Epidemiology and Demographics

The incidence in angiographic studies is .08% to .3% (usually an incidental finding at the time of angiography for another problem), but is important to know that the true incidence is unknown given that many coronary artery fistulas are small and undetected in life. Coronary artery fistula remains a postmortem diagnosis, and 15% of coronary artery anomalies are due to coronary artery fistulas.

Natural History, Complications, Prognosis

  • Spontaneous closure can occur in infancy, but is unusual in adulthood.

In the March 2010 Circulation article titled “Predictors of Long-Term Adverse Outcomes in Patients With Congenital Coronary Artery Fistulae”, Valente et al discuss long-term outcomes of patients with treated and untreated coronary artery fistula (CAF) closure. [1] Specifically, investigation was directed at whether or notclinical and angiographic features associated with CAF closure (symptomatic heart failure, angina and myocardial infarction) predict adverse outcomes.

Major Complications

11 patients (15%) experienced symptomatic cardiomyopathy, coronary thrombosis and MI.

Predictors of adverse outcome

Both angiographic and clinical features were predictive of adverse outcome.

  1. Angiographic predictors
    Drainage of CAF into the coronary sinus (P<0.001)
  2. Clinical predictors
    *Hyperlipidemia (P<0.001)
    *Systemic hypertension (P<0.001)
    *Older age at diagnosis (P<0.001)
    *Diabetes (P=0.05)
    *Tobacco use (P=0.006)

Long-term complications

The investigators conclude that long-term complications of CAF closure may include:

Further considerations

Long-term anticoagulation is suggested as treatment for the high-risk CAF that drain into the coronary sinus. This condition is likely to be associated with long-term morbidities after closure.

Differentiation form other Disorders

On angiography, a coronary artery fistula must be distinguished from a tumor blush, or arterial blood flow to a myxoma.

Diagnosis

Symptoms

  • CHF occurs in about 20% of these patients, usually with fistulas draining into the RV or RA.
  • Those draining into the left side of the heart cause dyspnea, fatigue or ischemia.
  • There is no good relationship between the size of the fistula and symptoms.

Physical Examination

Heart

Laboratory Findings

Electrocardiogram

  • May show chamber enlargement

Chest X Ray

Echocardiography or Ultrasound

Treatment

Surgery and Device Based Therapy

Indications for Surgery

Surgical Outcomes

  • Most have an improvement in symptoms postoperatively.


2008 ACC/AHA Guidelines for the Management of Adults With Congenital Heart Disease (DO NOT EDIT)[2]

Coronary Arteriovenous Fistula (DO NOT EDIT)[2]

Class I
"1. If a continuous murmur is present, its origin should be defined either by echocardiography, MRI, CTangiography, or cardiac catheterization. (Level of Evidence: C)"
”2. A large coronary arteriovenous fistula (CAVF), regardless of symptomatology, should be closed via either a transcatheter or surgical route after delineation of its course and its potential to fully obliterate the fistula. (Level of Evidence: C)"
”3. A small to moderate CAVF in the presence of documented myocardial ischemia, arrhythmia, otherwise unexplained ventricular systolic or diastolic dysfunction or enlargement, or endarteritis should be closed via either a transcatheter or surgical approach after delineation of its course and its potential to fully obliterate the fistula. (Level of Evidence: C)"
Class III
"1. Patients with small, asymptomatic CAVF should not undergo closure of CAVF. (Level of Evidence: C)"
Class IIa
"1. Clinical follow-up with echocardiography every 3 to 5 years can be useful for patients with small, asymptomatic CAVF to exclude development of symptoms or arrhythmias or progression of size or chamber enlargement that might alter management. (Level of Evidence: C)"

References

  1. ↑ Valente AM, Lock JE, Gauvreau K; et al. (2010). "Predictors of Long-Term Adverse Outcomes in Patients With Congenital Coronary Artery Fistulae". Circ Cardiovasc Interv. doi:10.1161/CIRCINTERVENTIONS.109.883884. PMID 20332380. Unknown parameter |month= ignored (help)
  2. ↑ 2.0 2.1 Warnes CA, Williams RG, Bashore TM, Child JS, Connolly HM, Dearani JA; et al. (2008). "ACC/AHA 2008 guidelines for the management of adults with congenital heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Develop Guidelines on the Management of Adults With Congenital Heart Disease). Developed in Collaboration With the American Society of Echocardiography, Heart Rhythm Society, International Society for Adult Congenital Heart Disease, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons". J Am Coll Cardiol. 52 (23): e1–121. doi:10.1016/j.jacc.2008.10.001. PMID 19038677.


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