Screening for fibromuscular dysplasia after spontaneous coronary artery dissection unmasks a massive right renal artery aneurysm requiring ex vivo surgical resection and autotransplantation

Abstract

Spontaneous coronary artery dissection (SCAD) is an increasingly recognised cause of acute coronary syndrome predominantly affecting women (>90% of cases) that is frequently associated with other arteriopathies, such as fibromuscular dysplasia (FMD) and migraine. We present a case of multi-vessel SCAD in a woman in her 40s presenting with myocardial infarction in whom incidental widespread FMD was found, including a massive right renal artery aneurysm requiring ex vivo resection, repair and autotransplantation. The case underscores the need for routine angiographic screening for FMD, which has a shared genetic risk with SCAD, and is associated with aneurysms, stenoses and hypertension.

Full text

1
McGrath- CadellL, etal. BMJ Case Rep 2025;18:e263132. doi:10.1136/bcr-2024-263132
Screening for fibromuscular dysplasia after
spontaneous coronary artery dissection unmasks a
massive right renal artery aneurysm requiring ex vivo
surgical resection andautotransplantation
Lucy McGrath- Cadell,1,2 Munish Heer,3 Nikhil Mahajan,3 Robert Graham 1,2,3,4
Case report
To cite: McGrath- CadellL,
HeerM, MahajanN,
etal. BMJ Case Rep
2025;18:e263132.
doi:10.1136/bcr-2024-
263132
1Molecular Cardiology, Victor
Chang Cardiac Research
Institute, Darlinghurst, New
South Wales, Australia
2St Vincent’s Hospital School of
Medicine, University of NSW,
Sydney, New South Wales,
Australia
3Hunter New England Local
Health District, New Lambton,
New South Wales, Australia
4Cardiology, St Vincent’s
Hospital, Sydney, New South
Wales, Australia
Correspondence to
Dr Robert Graham;
b. graham@ victorchang. edu. au
Accepted 4 February 2025
© BMJ Publishing Group
Limited 2025. Re- use
permitted under CC BY- NC. No
commercial re- use. See rights
and permissions. Published by
BMJ Group.
SUMMARY
Spontaneous coronary artery dissection (SCAD) is
an increasingly recognised cause of acute coronary
syndrome predominantly affecting women (>90%
of cases) that is frequently associated with other
arteriopathies, such as fibromuscular dysplasia (FMD)
and migraine. We present a case of multi- vessel SCAD
in a woman in her 40s presenting with myocardial
infarction in whom incidental widespread FMD
was found, including a massive right renal artery
aneurysm requiring ex vivo resection, repair and
autotransplantation. The case underscores the need for
routine angiographic screening for FMD, which has a
shared genetic risk with SCAD, and is associated with
aneurysms, stenoses and hypertension.
BACKGROUND
Fibromuscular dysplasia (FMD) is a non-
atherosclerotic, non- inflammatory vasculop-
athy that predominately affects women (>90%
of cases) with a mean age at diagnosis of 52
years.1 It is due to dysplastic growth of medium-
sized arteries that can lead to arterial stenoses,
aneurysms or dissections. It is often occult,
with the diagnosis being made incidentally on
imaging (as in this case), as part of an investi-
gation of early/onset and/or resistant renovas-
cular hypertension (the renal arteries being most
commonly involved), or as a result of finding
other commonly associated vasculopathies, such
as cervical artery dissection or, as in this case,
spontaneous coronary artery dissection (SCAD).2
However, it is often either not screened for or
is incompletely screened for in clinical practice.
Such screening is essential,3 as FMD predisposes
to thrombi and lifelong aspirin is recommended.4
FMD may also have other management challenges
as it can cause arterial aneurysms, such as high-
lighted in this case, which if undiagnosed and/
or not treated appropriately can be catastrophic.
Like FMD, SCAD also has a predilection for
women, who present at approximately the same
age.1 However, it is not due to dysplastic arterial
growth but to a bleed within the medial layer of
an epicardial coronary artery wall resulting in a
haematoma, with or without associated disrup-
tion of the intima. This leads to compression of
the artery lumen, reduced blood flow and, hence,
myocardial ischaemia, infarction or death.
CASE PRESENTATION
A woman in her 40s was admitted for the acute
onset of chest heaviness radiating down both
arms, which developed while coaching tennis.
She had previously been a professional tennis
player (table 1). Associated with this active
exercise, she had developed chest heaviness
2 days prior that had subsided without inter-
vention. The ambulance team noted a single
run of conscious, self- resolving, ventricular
tachycardia. The initial blood pressure was
140/82 mmHg, and the heart rate was 57 beats
per minute. At the hospital, the initial ECG
showed inferior ST elevation.
The medical history was significant for a
previous pregnancy at age 36 years, and six
or seven miscarriages attributed to a methy-
lenetetrahydrofolate reductase variant. She had
a Mirena intrauterine device for 2 years before
admission. There was a history of deep venous
thrombosis and infrequent migraines.
INVESTIGATIONS
Coronary angiography demonstrated normal
left main, left anterior descending and domi-
nant circumflex arteries. The ramus interme-
diate artery had a distal long segment of stenosis
with contrast hang- up suggestive of type 1
SCAD (figure 1a). The right coronary artery
was a non- dominant, small calibre vessel with
a long segment of distal disease suggestive of
SCAD (figure 1b). A left ventriculogram showed
normal overall systolic function with preserved
apical and basal function and mid- anterior and
inferior wall hypokinesis and only a borderline
increase in left ventricular end- diastolic pres-
sure (14 mm Hg). A transthoracic echocardio-
gram 2 days after admission was significant for
a left ventricular ejection fraction of 58% with
hypokinesis of mid- inferoposterior wall and
no significant valvular pathologies. However,
of note, a CT coronary angiogram performed
2 days after admission failed to show the coro-
nary dissections.
Laboratory tests during the 4- day hospitalisation
demonstrated a mild leucocytosis but an otherwise
normal full blood count. Renal function and electrolytes
were normal. Troponin I peaked at 8196 ng/L (refer-
ence range <16 ng/L). Cholesterol and triglyceride
levels were normal.
on March 15, 2025 by guest. Protected by copyright.http://casereports.bmj.com/BMJ Case Rep: first published as 10.1136/bcr-2024-263132 on 14 March 2025. Downloaded from

2McGrath- CadellL, etal. BMJ Case Rep 2025;18:e263132. doi:10.1136/bcr-2024-263132
Case report
An aortic CT angiogram showed no evidence of aortic dissection,
but incidental bilateral renal artery beading with a 22 × 11 mm right
renal artery fusiform aneurysm as well as focal stenosis of the coeliac
trunk with tiny fusiform and saccular aneurysms of the left renal and
splenic arteries, most likely reflective of FMD, was noted.
TREATMENT
In the absence of intractable symptoms or haemodynamic instability,
as recommended by multiple guidelines,5 6 the patient’s SCAD was
managed conservatively, given that SCAD survivors are at higher risk
for iatrogenic dissection with percutaneous coronary interventions
and most SCAD lesions heal spontaneously on follow- up imaging
within about 35 days.6
The patient was treated with dual antiplatelet therapy
(aspirin 100 mg and clopidogrel 75 mg daily), beta blockade
(metoprolol 50 mg two times per day), an angiotensin-
converting enzyme 2 inhibitor (perindopril 2 mg daily) and
a statin (rosuvastatin 20 mg daily).
OUTCOME AND FOLLOW-UP
A CT angiogram of the head and neck showed no features to suggest
FMD or vasculitis. 3 months after hospitalisation, a diagnostic inva-
sive renal artery angiogram (figure 2a,b) was performed to further
assess the anatomy of the right renal artery aneurysm and to decide
whether to treat the aneurysm endovascularly or with open surgery.
Given the type (fusiform) and size of the aneurysm and its pres-
ence in a woman within the childbearing age (criteria for aneurysm
repair), a 10- hour elective open surgical procedure was undertaken
6 months after the SCAD episodes, involving a laparoscopic right
nephrectomy with ex vivo resection of the aneurysm, plication of
the aneurysm and then autotransplantation into the right iliac fossa.
The engrafted kidney was well perfused with normal function on
renal nuclear perfusion scanning 2 days after surgery. Clopidogrel
was ceased at 8 months after the initial SCAD presentation, and the
patient was continued only on aspirin and perindopril.
From a renal perspective, renal function remains normal
with an eGFR of 80 mL/min/1.73 m2. The patient requires
only 2 mg perindopril per day for good blood pressure
control, now at 3 years postsurgical repair. A follow- up CT
angiogram of the chest, abdomen and pelvis demonstrated
nodularity of the left renal artery in keeping with FMD,
with similar nodularity identified within the internal iliac
graft supplying the right iliac fossa autotransplanted kidney.
There was asymptomatic involvement of the mesenteric and
coeliac arteries with focal stenoses, and splenic artery with
tiny fusiform and saccular aneurysms.
An ECG- gated, single- photon emission computed tomog-
raphy (SPECT) study, performed 2 months after the SCAD
episode, showed findings consistent with a moderate- sized
inferior wall myocardial infarct, peri- infarct inducible isch-
aemia and a left ventricular ejection fraction of 50%.
Table 1 Timeline of clinical events and diagnostic findings
Time Events
2 days before presentation Chest heaviness while undertaking active exercise
(playing tennis) that subsided.
Day 0 Admitted to hospital with chest heaviness. ECG—
inferior ST elevation.
Coronary angiography diagnoses spontaneous
coronary artery dissections. Conservative
management initiated.
Aortic CT angiogram reveals incidental renal and
mesenteric fibromuscular dysplasia (FMD) and right
renal artery aneurysm.
Day 2 CT coronary angiogram—dissections not visualised.
Echocardiogram—left ventricular ejection fraction
58% with hypokinesis of mid- inferoposterior wall
and no significant valvular pathologies.
Day 7 CT angiogram head and neck—no FMD.
2 months after presentation ECG- gated single- photon emission computed
tomography—moderate- sized inferior wall infarct,
peri- infarct inducible ischaemia and left ventricular
ejection fraction of 50%.
3 months after presentation Diagnostic invasive renal artery angiogram.
6 months after presentation Laparoscopic right nephrectomy with ex vivo
resection of the aneurysm, plication of a small
aneurysm and autotransplantation into the right
iliac fossa.
2 years after presentation Echocardiogram—left ventricular ejection fraction
65%, with mild localised segmental dysfunction.
Normal renal function and good blood pressure
control. Normal, baseline functional status.
CT, Computerised tomography; ECG, Electrocardiogram; FMD, Fibromuscular dysplasia.
Figure 1 Coronary angiography left coronary system. (a) Long
segment type 1 spontaneous coronary artery dissection (SCAD) from
mid- vessel in the ramus intermediate artery (arrow). While the LAD
could be interpreted as showing some tapering to suggest SCAD
involvement, on a different projection (not shown), it clearly fills
normally. (b) Coronary angiography right coronary system. Distal subtle
long segment SCAD in the early take- off right posterior descending
coronary artery (arrow).
Figure 2 Invasive renal angiography. (a) Bilateral renal artery beading
indicative of renal fibromuscular dysplasia and a fusiform right renal
artery aneurysm. (b) Invasive renal angiography. Fusiform right renal
artery aneurysm measuring at its widest: 22.45 x 10.94 mm.
on March 15, 2025 by guest. Protected by copyright.http://casereports.bmj.com/BMJ Case Rep: first published as 10.1136/bcr-2024-263132 on 14 March 2025. Downloaded from

3
McGrath- CadellL, etal. BMJ Case Rep 2025;18:e263132. doi:10.1136/bcr-2024-263132
Case report
The patient had no complications over the subsequent 3
years of follow- up. From a cardiac perspective, a 15- month
echocardiogram showed a normal ejection fraction of 65%,
with a mild localised segmental region of dysfunction of the
left ventricle. There were no haemodynamically significant
valvular abnormalities, and the pulmonary pressure was
normal. The rosuvastatin was ceased, since lipid levels were
normal and there was no reason to continue this medication,
as supported by guidelines.6
DISCUSSION
In this case, CT angiography was performed primarily to
exclude an aortic aneurysm or dissection. Hence, the diag-
nosis of FMD was serendipitous. Proactive angiographic
screening is recommended in all cases of SCAD because of
its common association with FMD. When such screening
is undertaken prospectively, FMD is found in 45–72% of
cases.3 7 The large size (2.25 × 1.09 cm) of the right renal
artery aneurysm was felt to carry a high risk of rupture,
particularly in a patient who undertakes active and vigorous
sports regularly and professionally, with attendant increases
in blood flow and shear stress. The criteria for repair of
renal artery aneurysms include size (>2 cm) and female
gender within the childbearing age, which were present in
this case. Other criteria not present include symptoms like
pain and haematuria, refractory hypertension, thromboem-
bolism, dissection and rupture.8 Fusiform aneurysms are
generally treated surgically, whereas other types (saccular
and intralobar) are treated by endovascular repair.8 Hence,
surgical repair was undertaken, with an ex vivo approach
determined to be the best option, where access to the aneu-
rysm was more convenient. This involved a protracted proce-
dure but with good outcomes, evidenced by normal renal
function and mild residual hypertension easily controlled
with minimal therapy. As is not uncommonly found, FMD
involved not only the renal arteries but also the coeliac trunk
and splenic and iliac arteries, but not those of the neck and
intracranial circulation. FMD involvement of the external
and internal carotid or vertebral arteries is a risk factor for
cervical artery dissection, whereas aneurysms in the cere-
bral circulation, occurring in up to 12.5%,9 require careful
surveillance and may warrant surgical repair, if considered
to be at risk of rupture or are impinging on vital brain struc-
tures. There are similar prevalences reported for extracere-
bral aneurysms in SCAD cohorts.9 However, the prevalence
of patients with SCAD and concurrent FMD with large
aneurysms requiring surgery as well as in the spectrum of
FMD severity in SCAD has not been determined.
The SCAD- affected arteries in this case were small calibre,
non- dominant and distal vessels supplying a relatively
small myocardial territory. Additionally, the patient was
Figure 3 Key learning points for the management of spontaneous
coronary artery dissection (SCAD) and fibromuscular dysplasia (FMD).
Patient’s perspective
As a professional athlete, I was devastated to learn that I had an
SCAD heart attack and even more so when I found out that I had
fibromuscular dysplasia with a large aneurysm that could have
ruptured at any time. It was also of concern that the Emergency
Room physicians and nurses knew very little about SCAD and
FMD, so I was fortunate to then find specialists who did. Clearly,
I am delighted that I received excellent care and am now very
well, but my case highlights the importance of having doctors
who are familiar with SCAD and FMD and the need for detailed
investigations to optimise my outcomes.
Learning points
►As summarised in figure3, it is important for patients
presenting with spontaneous coronary artery dissection
(SCAD) to undergo a comprehensive assessment for
fibromuscular dysplasia (FMD). Current recommendations
are CT or magnetic resonance angiography from head
to pelvis.4 13 The importance of this screening strategy is
highlighted in this patient, in whom multiple vascular beds
were found to be affected, including the renal, mesenteric
and iliac arteries, with sparing of the cervical, vertebral and
intracranial vessels. FMD can result in a wide spectrum of
abnormalities ranging from subtle vascular irregularities
to florid beading, stenoses and aneurysms. This case is
an example of an extremely large renal aneurysm with
attendant imminent risk of rupture mandating open surgical
management and highlights the independent management
challenges of incidental severe FMD in a patient with SCAD.
►Although FMD has not been found to be a predictor for
SCAD recurrences, it is a risk factor for an SCAD occurrence.6
Other risk factors in this patient include exposure to high
levels of sex hormones, given her multiple pregnancies and
miscarriages and occupational factors (extreme exertion as
a professional athlete). Although not yet formally evaluated
in prospective studies, it is advisable that SCAD patients
avoid isometric and high- intensity exercise, as well as
prolonged Valsalva manoeuvres. They should also be advised
about the implications of future pregnancies and hormonal
contraceptive use.
►Finally, given that the internal iliac graft supplying the right
iliac fossa autotransplanted kidney is also possibly affected
by FMD, although without stenoses, careful surveillance with
regular CT angiography or Doppler ultrasonography, generally
every 6 to 12 months, is advisable. Similar surveillance of the
other FMD- affected vessels is also advisable. Although FMD
involvement could result in dissection or infarction of the
autotransplanted kidney, end- stage kidney failure from renal
artery FMD is quite rare.4
on March 15, 2025 by guest. Protected by copyright.http://casereports.bmj.com/BMJ Case Rep: first published as 10.1136/bcr-2024-263132 on 14 March 2025. Downloaded from

4McGrath- CadellL, etal. BMJ Case Rep 2025;18:e263132. doi:10.1136/bcr-2024-263132
Case report
haemodynamically stable despite evidence of multi- vessel
coronary artery involvement, a moderate- sized inferior wall
myocardial infarct, peri- infarct inducible ischaemia and a
slightly reduced left ventricular ejection fraction of 50%.
The patient’s stability led to conservative therapy being
chosen as most appropriate, a decision supported by SCAD
guidelines.10 There is contention about antiplatelet therapy
to reduce intraluminal thrombosis formation since SCAD is
primarily a bleeding disorder.1 For this reason, the manage-
ment of SCAD is moving towards less antiplatelet therapy
due to the findings of recent registry studies.11 12 It might
be argued that the duration of dual anti- platelet therapy in
this patient was too prolonged in this case, but randomised
control data to address this issue are not yet available.
SCAD may not be detectable on CT coronary angiog-
raphy.5 This was evident in this case, where a CT coro-
nary angiogram was performed on a Siemens SOMATOM
Force dual energy scanner with axial plane acquisition to
a slice thickness of 0.75 mm and resolution of ~0.2 mm
with reconstructed images (curved vessels, 3D coronary and
cardiac echo reconstruction) on Syngo 2 days after presenta-
tion was unable to demonstrate the lesions, presumably due
to the involved vessels being small calibre, distal arteries.
Hence, invasive angiography, with a resolution of ~0.1 mm,
and in some cases, multimodality imaging, such as intravas-
cular ultrasonography or optical coherence tomography, are
required for SCAD to be diagnosed accurately.3
Contributors RG is the guarantor of this work. All authors contributed
substantially to the case as outlined in the attached author statements document.
Funding This study was funded by National Health and Medical Research Council
(GNT2013809), National Heart Foundation of Australia (106228).
Competing interests None declared.
Patient consent for publication Consent obtained directly from patient(s).
Provenance and peer review Not commissioned; externally peer reviewed.
Open access This is an open access article distributed in accordance with the
Creative Commons Attribution Non Commercial (CC BY- NC 4.0) license, which
permits others to distribute, remix, adapt, build upon this work non- commercially,
and license their derivative works on different terms, provided the original work
is properly cited and the use is non- commercial. See:http://creativecommons.org/
licenses/by-nc/4.0/.
Case reports provide a valuable learning resource for the scientific community and
can indicate areas of interest for future research. They should not be used in isolation
to guide treatment choices or public health policy.
ORCID iD
RobertGraham http://orcid.org/0000-0002-1042-2587
REFERENCES
1 Iismaa SE, Hesselson S, McGrath- Cadell L, etal. Spontaneous Coronary Artery
Dissection and Fibromuscular Dysplasia: Vasculopathies With a Predilection for
Women. Heart Lung Circ 2021;30:27–35.
2 Georges A, Yang M- L, Berrandou T- E, etal. Genetic investigation of fibromuscular
dysplasia identifies risk loci and shared genetics with common cardiovascular
diseases. Nat Commun 2021;12:6031.
3 Saw J, Aymong E, Sedlak T, etal. Spontaneous coronary artery dissection: association
with predisposing arteriopathies and precipitating stressors and cardiovascular
outcomes. Circ Cardiovasc Interv 2014;7:645–55.
4 Olin JW, Gornik HL, Bacharach JM, etal. Fibromuscular Dysplasia: State of the Science
and Critical Unanswered Questions. Circulation 2014;129:1048–78.
5 Collet J- P, Thiele H, Barbato E. The “Ten Commandments” for the 2020
ESC Guidelines for the management of acute coronary syndromes in
patients presenting without persistent ST- segment elevation. Eur Heart J
2020;41:3495–7.
6 Hayes SN, Kim ESH, Saw J, etal. Spontaneous Coronary Artery Dissection: Current
State of the Science: A Scientific Statement From the American Heart Association.
Circulation 2018;137:e523–57.
7 Combaret N, Gerbaud E, Dérimay F, etal. National French registry of spontaneous
coronary artery dissections: prevalence of fibromuscular dysplasia and genetic
analyses. EuroIntervention 2021;17:508–15.
8 Titze N, Ivanukoff V, Fisher T, etal. Surgical repair of renal artery aneurysms. Proc (Bayl
Univ Med Cent) 2015;28:499–501.
9 Androulakis E, Kourek C, Vrettos A, etal. Assessment of extra- coronary peripheral
arteriopathy in spontaneous coronary dissection: state of the art in non- invasive
imaging techniques and future perspectives. Eur Heart J Imaging Methods Pract
2023;1:qyad044.
10 Saw J, Mancini GBJ, Humphries KH. Contemporary Review on Spontaneous Coronary
Artery Dissection. J Am Coll Cardiol 2016;68:297–312.
11 Cerrato E, Giacobbe F, Quadri G, etal. Antiplatelet therapy in patients with
conservatively managed spontaneous coronary artery dissection from the multicentre
DISCO registry. Eur Heart J 2021;42:3161–71.
12 Garcia- Guimaraes M, Masotti M, Sanz- Ruiz R, etal. Clinical outcomes in spontaneous
coronary artery dissection. Heart 2022;108:1530–8.
13 Persu A, Lopez- Sublet M, Al- Hussaini A, etal. Prevalence and Disease Spectrum of
Extracoronary Arterial Abnormalities in Spontaneous Coronary Artery Dissection.
JAMA Cardiol 2022;7:159.
Copyright 2025 BMJ Publishing Group. All rights reserved. For permission to reuse any of this content visit
https://www.bmj.com/company/products-services/rights-and-licensing/permissions/
BMJ Case Report Fellows may re-use this article for personal use and teaching without any further permission.
Become a Fellow of BMJ Case Reports today and you can:
►Submit as many cases as you like
►Enjoy fast sympathetic peer review and rapid publication of accepted articles
►Access all the published articles
►Re-use any of the published material for personal use and teaching without further permission
Customer Service
If you have any further queries about your subscription, please contact our customer services team on +44 (0) 207111 1105 or via email at support@bmj.com.
Visit casereports.bmj.com for more articles like this and to become a Fellow
on March 15, 2025 by guest. Protected by copyright.http://casereports.bmj.com/BMJ Case Rep: first published as 10.1136/bcr-2024-263132 on 14 March 2025. Downloaded from