Introduction:
Fistula is defined as an inappropriate connection between two body
parts, such as an organ or blood vessel and another structure. More
specifically, a coronary artery fistula (CAF) is an abnormal connection
between a coronary artery and a major vessel or cardiac chamber.
CAFs are extremely rare, can be asymptomatic, and are often detected
incidentally; thus, the true incidence remains elusive [1]. CAFs can
either be congenital or acquired.
Congenital CAFs are theorized to be secondary to incomplete embryonic
development, in which the sinusoids that normally communicate the great
vessels and chambers of the heart with the coronary arteries are
incompletely closed. Acquired CAFs can occur as a result of
atherosclerosis, procedure-induced trauma, or collagen vascular disease
[2].
Previous literature has demonstrated that CAFs are present in only
0.05−0.25% of patients who undergo coronary angiography and in 0.9% of
patients who undergo CTA [3].
Fistulas arising from the LAD constitute only 30% of CAFs, and those
draining into the left side of the heart constitute a mere 10%, which
was the case illustrated herein [4].
The American College of Cardiology recommends closure of all large
fistulas regardless of symptoms due to the vast potential for and
severity of complications, including ’theft’ from the adjacent
myocardium, thrombosis and embolism, cardiac failure, atrial
fibrillation, rupture, endocarditis/endarteritis, arrhythmias,
ST-elevation myocardial infarction/non-ST elevation myocardial
infarction, and even sudden cardiac death [5].
In this present case study, we describe a 41-year-old male with no
significant past medical, surgical, or family history who presented with
atypical chest pain.
The patient had a positive nuclear stress test and subsequently
underwent installation of a left heart catheter, which revealed a large
fistula between the LAD and the LV circumflex artery; however,
subsequent CTA failed to demonstrate any evidence of a fistula being
present.
We discuss the current imaging modalities and their respective
advantages and limitations, in addition to providing an overview of
disease management.