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Brain & Heart Thrombosis, essential thrombocythemia, and recurrent stroke

number of platelets and their function are associated with the chances, he would develop a new stroke. The basilar
stroke occurrence. This disorder is typically comorbid with thrombus most likely was secondary to an atherosclerotic
thrombocytosis and megakaryocytic hyperplasia in the plaque rupture (an acute event on a chronic one). It
bone marrow, with the former specifically contributing to is possible that an eddy current of blood flow might
the risks for thrombosis and hemorrhage. 2 have formed at the end of the large thrombus, causing a
The current case is particularly distinctive because no secondary hypercoagulable state. To tackle this, we treated
definite prothrombotic etiology could be identified after him with long-term anticoagulation with a plan to dissolve
conducting repeated tests over many years, despite the the whole thrombus or address the eddy current.
recurrent thrombotic events, until he was admitted to our As the patient had a history of peripheral arterial disease
institute due to acute strokes. This is probably because minor and was stable with anticoagulation, there might be an
hematological derangements in the peri-stroke period are underlying hypercoagulable state that contributed to the
sometimes overlooked, causing a lack of proper follow-up. formation of basilar thrombus and a prothrombotic state,
These aberrations may later prove to be a critical stroke despite the negative results for thrombophilia. Since we did
etiology and a “harbinger of havoc” in the future. The platelet not have the facility to perform round-the-clock monitoring
counts during our patient’s 1 admission (in our institute) of partial thromboplastin time, in which case unfractionated
st
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were 9 × 10 /µL, and during the 2 stroke, it was 8 × heparin is applied, we chose to use low-molecular-weight
nd
10 /µL. Interestingly, based on his previous medical records, heparin to dissolve the intraluminal thrombi. It has been
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we learned that his baseline platelets used to be borderline found that anticoagulation therapy in a subgroup of embolic
high, at around 4 × 10 /µL. Rarely, essential thrombocythemia stroke of undetermined source patients with abnormal serum
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is diagnosed in patients with high normal platelet counts d-dimer, thrombin-antithrombin complex, prothrombin
(between 350,000 and 600,000 platelets per microliter of blood) fragment, and fibrin monomer or having severe left atrial
that are persistent over a long period of time and has relevant enlargement was associated with a reduced rate of recurrent
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genetic components that warrant a supportive bone marrow stroke. Thus, in the case when it is not possible to pinpoint
examination, which is performed to rule out possibilities a hypercoagulable state or cardiac etiology in stroke cases,
other than essential thrombocythemia. In fact, if a patient is anticoagulation may be warranted in special cases. In the
aged over 60 years with over 1,50,000 platelets per microliter current case, our patient had been on acenocoumarol for
and has a history of thrombosis, he falls under the high-risk 17 years due to a lower limb ischemic incident and reported
category for essential thrombocythemia that necessitates strict no significant clinical event. He had a stroke secondary to
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follow-up. Hence, if this kind of information was available, we a big basilar thrombus, which occurred a few years after he
could have been able to detect essential thrombocythemia in stopped taking anticoagulant because of an incident of lower
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our patient at a much earlier phase, even before he presented limb hematoma. In the 2 occasion, he had a recurrent stroke
with acute stroke. Another uniqueness of our case was that our while not taking any anticoagulants and his condition had
patient had recurrent thrombotic events but never exhibited since remained stable after he resumed taking anticoagulant.
common vasomotor symptoms of thrombocythemia, such as Due to the non-availability of relevant facility at our
headache, nausea, vomiting, light-headedness, transient visual center, we did not conduct CYP2C19 testing for clopidogrel
disturbances, atypical chest pain, acral paresthesia, livedo resistance. However, we presumed that this patient had
reticularis, and erythromelalgia. clopidogrel resistance, since Asian populations have high
Patients who had a minor stroke in the initial prevalence of clopidogrel resistance with nearly 70% in
presentation, and improved significantly post- some communities, and he experienced a recurrent stroke
thrombolysis, can be considered for re-thrombolysis if a while on clopidogrel. 7
new stroke strikes within 3 months after the initial minor
stroke. In the present case, although not a minor stroke, 4. Conclusion
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we administered re-thrombolysis as a treatment for the In conclusion, prescribing anticoagulants for stroke
patient. The back-to-back thrombolysis sessions were patients who have experienced recurrent strokes of
administered too close to each other, with only 16 days unknown etiology while on antiplatelet, and who are in
apart. The rather small timeline gap in giving multiple an unknown prothrombotic state, should be considered,
thrombolytic treatments stands as a unique point of after deliberating over the pros and cons of such strategy
this case, and fortunately, the patient recovered without with their family. Endovascular therapy is not mandatory
presenting any catastrophic bleeding. In hindsight, we for all cases of basilar thrombus with acute stroke, because
should have anticoagulated him during the 1 presentation thrombolysis may be sufficient in special situations like in
st
to dissolve any new, evolving thrombus, so as to minimize this case, considering the clinical picture and natural history

Volume 2 Issue 3 (2024) 4 doi: 10.36922/bh.3741