Occlusion of A Congenital Right Coronary to Vena Cava Superior Fistula Induces Temporary Junctional Bradycardia and Atrial Fibrillation

Full text

Author's Accepted Manuscript
Occlusion of A Congenital Right Coronary to Vena
Cava Superior Fistula Induces Temporary Junctional
Bradycardia and Atrial Fibrillation
Edward Gabeler MD PhD, Yves de Greef MD PhD,
Paul Vermeersch MD PhD, Dirk Stockman MD,
Valerie Vandermotte MD, Bruno Schwagten MD
PhD
PII: S2214-0271(15)00281-X
DOI: http://dx.doi.org/10.1016/j.hrcr.2015.12.011
Reference: HRCR197
To appear in: Heart Rhythm Case Reports
Cite this article as: Edward Gabeler MD PhD, Yves de Greef MD PhD, Paul Vermeersch
MD PhD, Dirk Stockman MD, Valerie Vandermotte MD, Bruno Schwagten MD PhD,
Occlusion of A Congenital Right Coronary to Vena Cava Superior Fistula Induces
Temporary Junctional Bradycardia and Atrial Fibrillation, Heart Rhythm Case Reports,
http://dx.doi.org/10.1016/j.hrcr.2015.12.011
This is a PDF file of an unedited manuscript that has been accepted for publication. As a
service to our customers we are providing this early version of the manuscript. The
manuscript will undergo copyediting, typesetting, and review of the resulting galley proof
before it is published in its final citable form. Please note that during the production process
errors may be discovered which could affect the content, and all legal disclaimers that apply
to the journal pertain.
www.elsevier.com/locate/buildenv

1
Title:
Occlusion of A Congenital Right Coronary to Vena Cava Superior
Fistula Induces Temporary Junctional Bradycardia and Atrial Fibrillation
Short title:
Temporary arrhythmia after occlusion of a RCVCS fistula
Edward Gabeler*
1
MD PhD, Yves de Greef
1
MD PhD , Paul Vermeersch
2
MD PhD, Dirk Stockman
1
MD, Valerie Vandermotte
1
MD, Bruno Schwagten
1
MD PhD
*Corresponding author
E-mail: Edward EE Gabeler*- eeegabeler@hotmail.com cardiologist fellow electrophysiology, Yves de Greef-
yves.degreef@zna.be cardiologist electrophysiologist, Paul Vermeersch-paul.vermeersch@zna.be
interventional cardiologist, Dirk Stockman-dirk.stockman@zna.be cardiologist-electrophysiologist, Valerie
Vandermotte-valerie.vandermotte@zna.be medical doctor, Bruno Schwagten-bruno.schwagten@zna.be
cardiologist-electrophysiologist
Address:
1
Department of Cardiology and Electrophysiology,
2
Department of Interventional Cardiology, ZNA
Middelheim, Lindendreef 1, 2020 Antwerp, Belgium. Phone number: +32 3 280 3222
Competing interests
None declared.

2
Keywords
congenital right coronary-to-vena cava superior fistula-RCVCS, junctional bradycardia, paroxysmal atrial
fibrillation, Amplatzer plug, Bezold-Jarisch reflex
List of Abbreviations
AF, atrial fibrillation; CO, cardiac output; D1 first diagonal; LAD, left anterior descendens coronary artery;
PA, pulmonary artery; PCI, percutaneous coronary intervention; PVI, pulmonary vein isolation; PW,
pulmonary wedge ; RA, right atrium; RCVCS, right coronary- to- vena cava superior; RV, right ventricle;
SAN, sino-atrial node.
Introduction
The finding of a congenital right coronary-to-vena cava superior (RCVCS) fistula is extremely rare. The
overall prevalence of coronary artery fistulae is 0.02-0.9%
1-2
of which the coronary-to-pulmonary artery
fistula is the most common type (78%), and the coronary-to- vena cava superior fistula the least common (1.8
%). Symptoms such as dizziness, palpitations, angina, reduced exercise capacity and/or fatigue may
accompany this phenomenon, but most coronary fistulae are asymptomatic.
Patients who developed secondary pulmonary hypertension due to left-to-right shunting via the arteriovenous
fistula will likely be symptomatic as illustrated in this case report, whereas in normal pressure fistulas
symptoms are less frequent
3
.
Therapeutic occlusion of the fistula is, certainly in case of symptoms, recommended since an increased risk
exists for endocarditis, transient ischemic attacks, coronary steal phenomenon, pericardial tamponade,
myocardial ischemia and/or even hydrops fetalis when left untreated
4-6
.
Various treatment strategies are described, varying from cardiothoracic surgery to minimal invasive occlusion
by using devices like Amplatzer plugs and Gianturco coils
7
. Due to its rarity, tailor made therapy differs per
centre and depends on available expertise. Interestingly, to our knowledge this is the first case report
describing the relation of closing the fistula and triggering of arrhythmia, and raises the question of a potential
relation between paroxysmal atrial fibrillation (AF) and a coronary fistula.
Case presentation
A 63 year old woman presented with dizziness and fatigue since a few months. Besides a bilateral cataract
operation, her past medical history was unremarkable. No congenital abnormalities were reported in her
family. A Holter test revealed paroxysmal AF. After failure of anti-arrhythmic drugs, the patient opted to
undergo pulmonary vein isolation (PVI). An adjacent diagnostic coronary catheterization showed a large
RCVCS fistula (Figure 1A) with Qp: Qs of 1.83, next to significant stenoses of the mid LAD and D1 artery.
The measured hemodynamic parameters (all pressure values expressed in mmHg) were : CO 7,2 L/min (N:4-
8), Aorta pressure 149/58 (N:100-140/60-90), RA 11 (N:2-6), RV 41/9 (N:15-30/2-8), PW 11 (N: 9-18), PA
35/10 (N:15-30/8-15). A transesophageal echocardiogram and CT thorax revealed a large communicating
fistula originating from the right proximal coronary to the vena cava superior (Figure 2A+B), confirming a
slight increased right ventricular pressure and mean pulmonary pressure without tricuspid regurgitation. After
assessment by a multidisciplinary team of an electrophysiologist, an interventional cardiologist and a thoracic

3
surgeon, a successful occlusion with a 12mm Amplatz device prior to PCI and PVI was performed (Figure
1B). A clear increase of contrast filled collaterals from the right coronary artery was seen after closure.
Immediately after fistula closure a profound bradycardia occurred with a junctional escape rhythm of 40bpm
(Figure 3A) lasting for 20 minutes, followed by paroxysmal AF (Figure 3B) which converted spontaneously
after 13 hours. Volume suppletion was sufficient to treat the associated hypotension adequately. The patient
remained hemodynamically stable also after additional PCI of the LAD and D1. Planned PVI was cancelled
awaiting the response of the occlusion of the fistula on the cardiac rhythm. During a follow-up time of
11months, no AF recurrence occurred.
Discussion
This case report describes a unique case of a right coronary artery to vena cava superior (RCVCS) fistula in a
patient with paroxysmal AF. Immediately after fistula closure, a profound bradycardia consisting of a
junctional escape rhythm occurred followed by an episode of paroxysmal AF (Figure 3A+B). Two intriguing
questions arise from this case report: 1. How to explain the transient rhythmological findings after closure?,
and 2. Is there any relation between paroxysmal AF and the existence of a RCVCS fistula?
Most probable mechanism to explain question 1 is that the sudden hypovolemia after closure of the RCVCS
fistula triggered a Bezold-Jarisch reflex
8
via the muscarine non-myelinated afferent barosensor receptors in the
atria (M5) and ventricles (M3)
9
, followed by an increased parasympatic inhibition of the sinoatrial node and
atrioventricular conduction (SAN) via the C-efferent fibers
10
. Another potential mechanism is mechanical
compression during Amplatzer expansion on the upper right cardiac - and aortacaval ganglia leading to an
increased parasympathetic activity followed by sinus nodal inhibition. Also, a sudden hyperemia of the right
coronary myocardial area (as shown in Figure 1B by more contrast filled collaterals) could alternate the blood
flow in the sinus- and atrioventricular nodal artery. This sudden increased coronary flow may enhance
myocardial acidosis due to an increased myocardial oxygen demand on the basis of mechanoenergetic
disturbance
11
, which can be followed by the Bezold-Jarisch reflex. Other less probable mechanisms are
central mediated vagal overdrive due to prostaglandin, endothelin or A2A antagonist release in response to
fistula occlusion
12
, whether or not synergized with propofol induced hypovolemia leading to the Bezold
Jarisch reflex
13
. All these mechanisms would expected to be temporary, and therefore do not fully explain the
duration of the secondary arrhythmias.
Regarding the second question, could the fistula be a trigger of paroxysmal AF before closure or is it an
epiphenomon? The maintenance of sinus rhythm, almost one year after closure, suggests that there could be a
link. Potentially the higher right atrial pressure could lead to atrial stretch, which in itself is a proven
mechanism for focal firing of excitable regions
14-15
. Also, the inverse relation between atrial stretch and
autonomic inhibition lowering AF vulnerability via atrial autonomic ganglia
16
is well described. Closure of the
RCVCS fistula has the potential to stop the vicious circle of atria dilation due to increased atrial stretch as a
prerequisite for the domestication of AF
15
. Although suggested by the disappearance of AF, whether closure of
the fistula with presumed reverse remodeling of the atria is sufficient to maintain sinus rhythm overtime
remains to be seen. If AF would recur, it could very well be that potentially other more common AF initiating
mechanisms as excitable pulmonary foci were already present from the start or developed over time, further
limiting a causal relationship between AF and a coronary fistula. Therefore, although a relation between
paroxysmal AF and the RCVCS fistula in this case is suggested, the role of atriovenous fistula in the
development of AF remains speculative and needs to be further studied.

4
Conclusion
This case report highlights the potential occurrence of profound bradycardia and paroxysmal atrial fibrillation
after RCVCS fistula closure. Since the patient had paroxysmal atrial fibrillation before closure and was free of
atrial fibrillation after closure, a potential causal relation could exist between paroxysmal AF and RCVCS
fistula. This remains however to be proven.
Consent
Written informed consent was obtained from the patient for publication of this case report and any
accompanying images
Author’s contributions
Author 1 E.E.E. Gabeler MD PhD, participated in the coordination and the design, described the case and
drafted the manuscript, author 2 Y. De Greef MD PhD, participated in the design and drafting of the
manuscript, author 3 P. Vermeersch MD PhD, carried out the interventional technique, author 4 D. Stockman
MD PhD, participated in the design, author 5. V. Vandermotte, MD participated in the pre- and post
interventional patient care and author 5 B. Schwagten MD, PhD, participated in the design and coordination.
Key Teaching Points:
1. A congenital right coronary to vena cava superior (RCVCS) fistula is rare.
2. After RCVCS closure one has to be aware of the potential of temporary acute and subacute pro-
arrhythmogenic effects.
3. Disappearance of paroxysmal AF in long-term after closure of the RCVCS suggests a potential causal
link between paroxysmal AF and RCVCS fistula.
References
1. Yuksel S, Yasar E, Nar G, Gulel O, Demircan S, Yilmaz O, Sahin M. Prevalence and characteristics of coronary-cameral
communications in adult patients:coronary angiographic analysis of 16,573 patients. Med Princ Pract. 2014;23(4):336-9.
2. Lim JJ1, Jung JI, Lee BY, Lee HG. Prevalence and types of coronary artery fistulas detected with coronary CT
Angiography. AJR Am J Roentgenol. 2014 Sep;203(3):W237-43.Bhatia S
1
, Morrison JF, Bower TC, McGoon MD.
Pulmonary hypertension in the setting of acquired systemic arteriovenous fistulas. Mayo Clin Proc. 2003 Jul; 78(7):908-12.
3. Bhatia S
1
, Morrison JF, Bower TC, McGoon MD. Pulmonary hypertension in the setting of acquired systemic arteriovenous
fistulas. Mayo Clin Proc. 2003 Jul;78(7):908-12.
4. Jariwala U, Hasan RK, Thorn EM, Zakaria S.
An unusual case of infective endocarditis involving a right coronary artery
to superior vena cava fistula. Catheter Cardiovasc Interv. 2014 Jul 10.
5. Pagni S
1
, Austin EH, Abraham JS. Right coronary artery to superior vena cava fistula presenting with 'steal' phenomenon.
Interact Cardiovasc Thorac Surg. 2004 Dec; 3(4):573-4.
6. Ilhan E, Sahin S, Celebi A. Coronary fistulas can develop collateral vessels: angiographic follow-up of an embolized giant
right coronary artery-superior vena cava fistula in a patient with variant angina.
J Invasive Cardiol. 2011 Feb;23(2):E12-4.
7. Weymann A
1
, Lembcke A, Konertz WF. Right coronary artery to superior vena cava fistula: imaging with cardiac
catheterization, 320-detector row computed tomography, magnetic resonance imaging, and transoesophageal
echocardiography. Eur Heart J. 2009 Sep; 30(17):2146.
8. Mark AL, The Bezold-Jarisch reflex revisited: clinical implications of inhibitory reflexes originating in the heart. J Am Coll
Cardiol. 1983 Jan; 1(1):90-102.
9. Schultz HD
1
.Cardiac vagal chemosensory afferents. Function in pathophysiological states. Ann N Y Acad Sci. 2001 Jun;
940:59-73.

5
10. Wang H
1
, Han H, Zhang L, Shi H, Schram G, Nattel S, Wang Z. Expression of multiple subtypes of muscarinic
receptors and cellular distribution in the human heart. Mol Pharmacol. 2001 May; 59(5):1029-36.
11. Nisbet AM
1
, Burton FL
1
, Walker NL
1
, Craig MA
1
, Cheng H
2
, Hancox JC
2
, Orchard CH
2
, Smith GL
1
. Acidosis slows electrical
conduction through the atrio-ventricular node. Front Physiol. 2014 Jun 25; 5:233.
12. Iovino M
1
, Guastamacchia E, Giagulli VA, Fiore G, Licchelli B, Iovino E, Triggiani V. Role of central and peripheral
chemoreceptors in vasopressin secretion control. Endocr Metab Immune Disord Drug Targets. 2013 Sep; 13(3):250-5.
13. De Cosmo G
1
, Congedo E, Clemente A, Aceto P.Sedation in PACU: the role of propofol. Curr Drug Targets. 2005
Nov;6(7):741-4.
14. White CW, Kerber RE, Weiss HR, Marcus ML. The effects of atrial fibrillation on atrial pressure-volume
and flow relationships. Circ Res. 1982 Aug; 51(2):205-15.
15. Ravelli F
1
, Allessie M. Effects of atrial dilatation on refractory period and vulnerability to atrial fibrillation in the isolated
Langendorff-perfused rabbit heart. Circulation. 1997 Sep 2;96(5):1686-95.
16. Eckstein J
1
, Verheule S, de Groot NM, Allessie M, Schotten U. Mechanisms of perpetuation of atrial fibrillation in
chronically dilated atria. Prog Biophys Mol Biol. 2009 Jan;99(1):51.
17. Stavrakis S
1
, Nakagawa H
1
, Po SS
1
, Scherlag BJ
1
, Lazzara R
1
, Jackman WM
1
. The role of the autonomic ganglia in atrial
fibrillation. JACC Clin Electrophysiol. 2015 Mar-Apr;1(1-2):1-13.
Figure 1 A. An X-AP view showing clearly a right coronary to vena cava superior fistula (RCVCS).
Figure 1 B. A X-Cranial view showing the successfully deployed Amplatzer plug (arrows) in the proximal sac
that occludes the fistula. Note the increased collaterals from the right coronary artery (asterisks).
Figure 2 A. A Transesophageal short-axis view at 140 degrees, showing the large aneurysmatic sac at the
proximal right coronary artery and a part of the RCVCS fistula. B. A transversal coupe of a CT thorax with
contrast, showing the large right coronary (RCA) to vena cava superior (VCS) fistula (arrows).
Figure 3 A and B. Post- RCVCS arrhythmia sequence after closure. First a junctional escape rhythm of 40
bpm (panel A) lasting for 20 minutes, followed by paroxysmal AF (panel B) converting spontaneously after 13
hours.
RCVCS

6

7

8