Effects of ligation of a coronary artery
fistula on coronary blood flow

Shiro Miura, Masanao Naya, Osamu
Manabe, Akira Ando, Atsushi Usami,Chihoko Miyazaki, Takehiro Yamashita& Youhei Ohkawa
Journal of Nuclear Cardiology
ISSN 1071-3581
J. Nucl. Cardiol.
DOI 10.1007/s12350-019-02003-4

1 23

Your article is protected by copyright andall rights are held exclusively by American
Society of Nuclear Cardiology. This e-offprint
is for personal use only and shall not be selfarchived in electronic repositories. If you wish
to self-archive your article, please use theaccepted manuscript version for posting on
your own website. You may further deposit
the accepted manuscript version in any
repository, provided it is only made publicly
available 12 months after official publicationor later and provided acknowledgement isgiven to the original source of publication
and a link is inserted to the published article
on Springer's website. The link must be
accompanied by the following text: "The final
publication is available at link.springer.com”.

1 23

Author's personal copy
IMAGES THAT TEACH
Effects of ligation of a coronary artery fistulaon coronary blood flow
Shiro Miura, MD, MSc,a Masanao Naya, MD, PhD,bOsamu Manabe, MD, PhD,c Akira Ando, CNMT,a Atsushi Usami, CNMT,aChihoko Miyazaki, MD, PhD,a Takehiro Yamashita, MD, PhD, FACC,a andYouhei Ohkawa, MD, PhDaabc

Hokkaido Ohno Memorial Hospital, Sapporo, Japan
Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School ofMedicine, Hokkaido University, Sapporo, Japan
Department of Nuclear Medicine, Faculty of Medicine and Graduate School of Medicine,
Hokkaido University, Sapporo, Japan

Received Oct 25, 2019; accepted Nov 9, 2019
doi:10.1007/s12350-019-02003-4

A 60-year-old woman with a known right coronary
artery (RCA) to coronary sinus (CS) fistula presented
with a 2-month history of dyspnea and chest tightness onexertion and persistent atrial tachycardia. Chest X-ray
revealed biventricular dilation, which had not been seen
7 years before (Figure 1). The transthoracic echocardiography showed a normal left ventricular ejection
fraction with no wall motion abnormalities, enlargementof all four chambers, and left-to-right shunting with apulmonary-to-systemic flow ratio (Qp/Qs) of 1.3.
Transesophageal echocardiography demonstrated adilated, tortuous RCA, a fistula between the RCA anddilated CS, and stenosis of CS ostium oppressed by theReprint requests: Shiro Miura, MD, MSc, Hokkaido Ohno Memorial
Hospital, Sapporo, Japan; s.miura@ohno-kinen.or.jp
J Nucl Cardiol
1071-3581/$34.00
Copyright Ó 2019 American Society of Nuclear Cardiology.

dilated RCA (Figure 2). Computed tomography (CT)angiography confirmed the echocardiographic findings:
a significantly dilated and tortuous RCA and CS with asingle fistula between the terminal RCA and theaneurysmal CS (Figure 3). Additionally, an epicardial
collateral vessel was visualized from the distal left
anterior descending artery to the distal RCA. 13N-ammonia positron emission tomography (PET)/CT during
adenosine triphosphate (ATP)-induced coronary hyperemia revealed a reversible perfusion abnormality in theinferior and inferolateral regions of the left ventricle.
The coronary flow reserve ratio (CFR) was decreased inthe RCA territory (Figure 4A). The patient underwent

Author's personal copy
S. Miura et al
Effects of ligation of a coronary artery fistula on coronary blood flow

Journal of Nuclear CardiologyÒ

Figure 1. Chest X-ray PA view (A) revealed cardiac enlargement at a cardiothoracic ratio of 69%
compared with the 49% revealed in the chest X-ray done 7 years ago (B).

Figure 2. Two-dimensional transesophageal echocardiography demonstrates the massively dilated
distal RCA and aneurysmally dilated proximal CS (A). A turbulent color flow from the distal RCA
into the proximal part of the CS was identified as a single fistula by color Doppler flow imaging (B).
An enhanced flow into the RA from the narrow CS ostium, which seemed oppressed by the dilated
distal RCA with a peak velocity of 2.8 ms-1 at the narrow CS ostium, is visible. RCA, rightcoronary artery; CS, coronary sinus; RA, right atrium; RV, right ventricle.

Author's personal copy
Journal of Nuclear CardiologyÒS. Miura et al
Effects of ligation of a coronary artery fistula on coronary blood flow

Figure 3. CTA (volume-rendered anterior image) demonstrates an extremely enlarged RCA in fulllength with apparent aneurysmal dilatation in the terminal RCA, an enormously enlarged CS in theproximal portion, and a normal LCA (A). At maximal dilation, the RCA was 36 mm and the CS
was 24 mm, highlighting that no epicardial branch from the RCA was observed throughout theentire RCA. Instead, an epicardial collateral vessel was visualized from the distal LAD to the distal
RCA (red arrow heads). Axial-enhanced CTA clearly depicted a fistula between the terminal RCA
and proximal CS with distinct visualization of the narrow CS ostium compressed by the distal RCA(B). CTA, computed tomographic angiography; RCA, right coronary artery; CS, coronary sinus;
LCA, left coronary artery; LAD, left anterior descending coronary artery; RA, right atrium; RV, rightventricle; LV, left ventricle.

surgical ligation of the fistula under cardiopulmonary
bypass without grafting the distal RCA because of small
vessel size.1 PET/CT repeated 16 days after surgery
demonstrated a significant reduction in stress/rest
myocardial blood flow and CFR in the RCA territory
with a larger area of ischemia in the affected area
(Figure 4B). For pre and postoperative PET examinations, electrocardiograms were done at baseline andduring stress with ATP infusion (Figure 5). Althoughfrequent atrial arrhythmia and symptomatic hypotension

complicated the postoperative course, the patient wasdischarged 31 days after surgery and the 5-month postoperative follow-up was uneventful.
Herein, we considered through the novel case thatthe myocardial ischemia before surgery was likely due
to coronary steal phenomenon.2 The worsened ischemia
after surgery was likely due to thrombotic occlusion of
the RCA aneurysm. Overall, 13N-ammonia PET/CT canhelp assess the functional status and quantify coronary
blood flow in patients with coronary artery anomalies.3

Author's personal copy
S. Miura et al
Effects of ligation of a coronary artery fistula on coronary blood flow

Journal of Nuclear CardiologyÒFigure 4. 13N-ammonia PET/MPI demonstrating the preoperative reversible myocardial ischemia
on the posterior walls that was significantly expanded postoperatively concerning the location andextent throughout the RCA-supplied territory (A). ATP-induced stress/rest 13N-ammonia PET/CT
was performed to quantify MBF, myocardial perfusion, and CFR (B). The preoperative MBF at restand stress for the RCA were 2.12 mLg-1min-1 and 1.07 mLg-1min-1, respectively, and CFR for
the RCA was 1.97 with a localized drop in the RCA territory, which implies the possibility oflocalized microvascular dysfunction. Postoperatively, rest and stress MBF for the RCA showed asignificant decline to 1.44 mLg-1min-1, 0.60 mLg-1min-1, respectively, with a substantial dropin CFR over the RCA territory, suggesting severe myocardial ischemia potentially provoked by theenhanced turbulence flow effect. PET/MPI, positron emission tomography myocardial perfusion
imaging; SA, short axis; VLA, vertical long axis; HLA, horizontal long axis; MBF, myocardial bloodflow; CFR, coronary flow reserve; MBF, myocardial blood flow.

Author's personal copy
Journal of Nuclear CardiologyÒS. Miura et al
Effects of ligation of a coronary artery fistula on coronary blood flow

Figure 5. Preoperative electrocardiograms during 13N-ammonia PET showed within-normalranges at baseline (A) and an increased incidence in supraventricular premature contraction
without remarkable ST segment changes during ATP infusions (B). In contrast, postoperativeelectrocardiograms revealed a postoperative temporary epicardial pacing rhythm, a depression of
the ST segment in the anterior precordial leads, and a T wave inversion without pathological Q
wave both in the anterior precordial and limb leads at baseline (C). The findings were similar during
ATP perfusion with enhanced own beat at a heart rate of 78 (D). PET, positron emission
tomography; ATP, adenosine triphosphate.

Disclosure
The authors indicate that they have no financial conflictof interest.

2. Bauer EP, Piepho A, Klovekorn WP. Coronary arteriovenous
fistula: Surgical correction of a rare form. Thorac Cardiovasc Surg
1994;42:237-9.
3. Said SA, Agool A, Moons AH, Basalus MW, Wagenaar NR,
Nijhuis RL, et al. Incidental congenital coronary artery vascular
fistulas in adults: Evaluation with adenosine-(13)N-ammonia PETCT. World J Cardiol 2018;10:153-64.

References
1. Ozler A, Tarhan IA, Kehlibar T, Arslan Y, Yilmaz M, Dumantepe
M, et al. Resection of a right coronary artery aneurysm with fistula
to the coronary sinus. Ann Thorac Surg 2008;85:649-51.

Publisher’s Note Springer Nature remains neutral with regard tojurisdictional claims in published maps and institutional affiliations.