Barbara Eržen1
Native Aortic Valve Thrombosis:
What’s Behind? 
ABSTRACT
KEY WORDS: native aortic valve, thrombosis, cancer, transesophageal echocardiography
Native aortic valve thrombosis is an exceptionally rare and serious condition characterized
by the formation of a thrombus on the native aortic valve. It presents a significant clin-
ical challenge and can lead to severe complications, including heart failure or cardiogenic
shock due to a heart attack or aortic valve dysfunction, neurological issues such as stroke,
and peripheral embolisms affecting the arteries of the arms, legs, kidneys, and other organs.
Given the numerous potential causes of peripheral embolism, native aortic valve throm-
bosis is an extremely rare source. Due to its low incidence, there is limited data on its aeti-
ology, treatment, complications, and clinical outcomes, with most information derived from
individual case reports. It is imperative to identify the underlying cause, which frequently
poses a significant clinical challenge. We present the case of a 55-year-old patient with
a pronounced prothrombogenic condition, which manifested as a venous thromboembolism
and thrombosis of the native aortic valve. This condition led to a repeated embolism into
the central nervous system and peripheral arteries of the arms and legs. The underlying
cause of the prothrombogenic state was a newly diagnosed lung carcinoma.
1 Asist. dr. Barbara Eržen, dr. med., Klinični oddelek za žilne bolezni, Univerzitetni klinični center Ljubljana, Zaloška
cesta 7, 1000 Ljubljana; Katedra za inteno medicino, Medicinska fakulteta, Univerza v Ljubljani,, Zaloška cesta 7,
1000 Ljubljana; erzen_b@yahoo.com
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CASE REPORT
A previously healthy 55-year-old woman,
a non-smoker, presented to the angiology
outpatient clinic with a three-week history
of left swelling. Her medical history was
notable only for asthma. Clinical exami-
nation revealed no abnormalities other
than left leg calf swelling. An ultrasound
of the left leg veins indicated acute popliteal
and posterior tibial deep vein thrombosis
and treatment with therapeutic doses of
dalteparin was initiated.
Baseline laboratory tests, including
complete blood count, troponin level,
screening rheumatological examinations,
liver and kidney function, were normal,
except for an elevated D-dimer level of
21,114 μg/L. There was no clinical evi-
dence of infections. A chest X-ray showed
thickening in the left hilum but no other
pathological changes. One week later, the
patient reported tingling and weakness in
her right arm and leg. A head CT revealed
two acute ischemic lesions. Anticoagulant
therapy was immediately discontinued,
and a filter was inserted into the inferior
vena cava. Despite this, hemiparesis recurred
32 Barbara Eržen Native Aortic Valve Thrombosis: What’s Behind?
the next day, and a follow-up head CT
revealed another ischemic lesion measur-
ing 2 × 1 cm.
Suspecting paradoxical embolism,
a transthoracic echocardiography (TTE)
was performed, which showed a thickening
of the right and non-coronary aortic valve
leaflets, mild aortic valve insufficiency, no
shunt, and otherwise normal findings.
A transesophageal echocardiography (TEE)
confirmed a mass on the right and non-
coronary aortic valve leaflets (figure 1). To
further characterize the mass, a cardiac CT
angiography was performed, revealing hypo-
dense changes measuring 11×11×6mm on
the non-coronary leaflet, 7×7×6mm on the
right coronary leaflet, as well as a smaller
hypodense change on the left coronary
leaflet. These lesions did not enhance con-
vincingly after contrast administration and
were most likely thrombi. According to the
cardiosurgical council, surgical treatment
of the aortic valve thrombosis was not indi-
cated. The patient was treated conserva-
tively, initially with subtherapeutic doses of
dalteparin due to a recent ischemic stroke,
and after ruling out the haemorrhagic trans-
Figure 1. Transthoracic echocardiography (parasternal window, short axis) showing mass (thrombosis) on
the right and non-coronary aortic valve leaflets.
Angioloski 2024_Mr10_2.qxd  19.9.2024  8:46  Page 32
formation of ischemic lesions by a head CT,
therapeutic doses were resumed.
A contrast-enhanced chest CT showed
a 6.5 cm consolidation in the lingula sus-
picious for pulmonary malignancy, signs of
lymphangitic carcinomatosis, bilateral
pleural effusion, and a small pulmonary
thromboembolism. The preliminary radi-
ological stage was assessed as T3 N2 M1a.
An abdominal CT showed no signs of malig-
nancy in the abdomen. A head MRI revealed
multiple small acute ischemic lesions con-
sistent with microembolisms. A pleural
puncture confirmed a malignant exudate,
cytomorphological indicating non-small cell
carcinoma, most likely adenocarcinoma of the
lung. Molecular genetic testing revealed
the presence of a proto-oncogene tyrosine-
protein kinase-1 (ROS-1) gene fusion.
The thoracic-oncology council recom-
mended systemic immunotherapy with
entrectinib. However, before systemic targeted
therapy could be initiated, the patient’s con-
dition rapidly deteriorated despite thera-
peutic doses of dalteparin with recurrent
emboli affecting both the central nervous
system and peripheral arteries of the arms
and legs. She developed tetraparesis, and
acute ischemia of the fingers and toes,
and experienced severe pain. Unfortunately,
only palliative treatment was possible for
the patient, a palliative mobile unit was
activated, and the patient died two months
after the first symptoms appeared.
DISCUSSION
Unlike thrombosis on an artificial, mechan-
ical aortic valve, thrombosis on a native aor-
tic valve is extremely rare, resulting in very
limited data in the literature. However,
the number of published cases of throm-
bosis on native valves has increased with
each decade, primarily due to improved
imaging techniques. By 2020, 74 cases had
been described. That is why this condition
poses significant diagnostic and therapeu-
tic challenges (1).
The most common clinical presenta-
tions of aortic valve thrombosis are myocar-
dial infarction, acute limb ischemia, cere-
brovascular incidents, and heart failure
(1). In our clinical case, the first manifes-
tations were tingling and weakness in
patient's right arm and leg due to an
embolism into the central nervous system,
followed by several embolisms into the
peripheral arteries of the arms and legs,
resulting in acute limb ischemia.
The diagnostic work-up typically relies
on an echocardiography, particularly TEE,
due to its superior temporal and spatial
resolution compared with TTE (2). A TTE
with 59% and a coronary angiography
with 29% sensitivity are not sufficiently
sensitive examinations for detecting aortic
valve thrombosis. Therefore, it is essential
to perform either TEE or aortic root angio-
graphy, which achieves 100% sensitivity.
Other imaging modalities, such as cardiac
CT, can also be useful but may yield false
negatives, especially in cases involving
mobile thrombi (1). In our clinical case, in
addition to TEE, we also performed a CT
angiography of the heart to obtain addi-
tional information regarding the aetiology
of the mass on the valve.
Given the rarity of native aortic valve
thrombosis, it is essential to investigate
underlying causes thoroughly. In most
described cases, native aortic valve throm-
bosis occurs in hypercoagulable condi-
tions, with antiphospholipid syndrome
being the most common, in systemic con-
nective tissue disease, alternatively formed
on a diseased valve (calcifications), fol-
lowed by aortic root/valve structural abnor-
malities such as a bicuspid aortic valve,
degenerative aortic valve, left ventricular
assist device, hypoplastic left heart syn-
drome or as a consequence of trauma
(surgery catheterization) (1, 3). Therefore,
in the absence of structural abnormalities
of the aortic valve and endothelial lesions,
it is reasonable to check autoantibodies
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(anti-cardiolipin, lupus anticoagulants,
anti-b2GPI antibodies), tumour markers,
and coagulopathy markers (prothrombin
gene mutation, C-S protein deficiency, anti-
thrombin III, resistance to activated pro-
tein C). We must also always consider the
possibility of an underlying malignancy and
conduct a thorough screening for cancer (4).
In our case, we observed simultaneous
deep vein thrombosis and thrombosis on
the native aortic valve. Suspecting an occult
malignancy, we performed a CT scan of the
abdomen and chest, which revealed a tumour
in the lingula. This tumour was diagnosed
as non-small cell carcinoma, most likely
adenocarcinoma of the lung. We have found
another case report in the literature describ-
ing thrombotic masses on the native aor-
tic and mitral valves in a patient with lung
cancer (5).
Differentiating native aortic valve throm-
bosis from tumours, particularly papillary
fibroelastoma, which is the most common
valvular tumour, can be challenging. Both
native valve thrombus and papillary fibro-
elastoma can cause systemic embolic
events (6). The definitive diagnosis is made
histologically.
The risk of in-hospital clinical deterio-
ration in patients with native aortic valve
thrombosis is 38%, and the overall in-hos-
pital mortality is 20% (1). Therefore, native
aortic valve thrombosis predicts an un-
favourable prognosis. Some authors advo-
cate for the prompt surgical resection of this
valvular disease, regardless of its size and
shape, not only to confirm the pathology
but also due to the potential for life-threat-
ening complications from a left-sided mass
and for representing a poor prognosis (5).
Due to the lack of evidence, decision-
-making regarding the treatment approach
is often based on individualized care, the
recommendations of a heart team, or expert
opinion. Anticoagulation treatment deci-
sions are complex, especially when central
nerve system embolisms prevent treat-
ment with therapeutic doses of anticoagu-
lant drugs. The optimal treatment approach
is unclear; there are no guidelines to defin-
itively recommend thrombectomy accom-
panied with anticoagulation versus anti-
coagulation alone.
Our patient was treated conservatively
with anticoagulation and supportive the-
rapy. Based on the systematic review, patients
who were not treated with thrombectomy
and those who experienced clinical deterio-
ration or recurrence during hospitalization
had worse outcomes with statistically sig-
nificant increased in-hospital mortality (1).
In our case, a neurological complication
(hemiparesis) recurred during hospitaliza-
tion and, according to the cardio surgery
council, she was treated conservatively
without surgery, which was somehow
understandable given the newly discovered
metastatic malignant disease (2). However,
thrombectomy is worth considering in
patients who are otherwise reasonable can-
didates for surgery.
In our patient, following conservative
treatment, the condition rapidly deterio-
rated due to recurrent central and periph-
eral embolisms, resulting in critical limb
ischemia. Consequently, only palliative
therapy could be administered, and the
patient passed away two months after the
onset of the initial symptoms. This case
underscores the severity and extremely
poor prognosis associated with aortic valve
thrombosis. In any case, serious consider-
ation of operative treatment would be nec-
essary in the absence of disseminated
malignancy. The literature review indi-
cates that surgical intervention has a bet-
ter outcome in these cases (1).
CONCLUSIONS
A thrombosis on the native aortic valve is
an extremely rare, urgent, and dangerous
condition with a poor prognosis and high
mortality. It is essential to investigate
underlying causes thoroughly. Rapid action
34 Barbara Eržen Native Aortic Valve Thrombosis: What’s Behind?
Angioloski 2024_Mr10_2.qxd  19.9.2024  8:46  Page 34
and treatment are necessary, though chal-
lenging, as decisions often must be made
on a case-by-case basis. Due to the rarity
of the disease and the consequent lack of
data, there are no established guidelines.
There is a need to report cases that can
35Med Razgl. 2024; 63 Suppl 2:
enhance knowledge about this condition.
Our report represents a rare case of spon-
taneous native aortic valve thrombosis in
a patient with newly discovered pulmonary
carcinoma, who was treated conserva-
tively.
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