Apollo Medicine

CASE REPORT
Year
: 2021  |  Volume : 18  |  Issue : 3  |  Page : 212--214

The utility of “heart sign” on neuroimaging in acute-onset quadriparesis: A series of three cases


S Sheetal1, Antony Kalliath2, Aswathy Sasidharan1, S Vijayalekshmi1,  
1 Department of Neurology, Pushpagiri Institute of Medical Sciences and Research Centre, Thiruvalla, Kerala, India
2 Department of Critical Care, Pushpagiri Institute of Medical Sciences and Research Centre, Thiruvalla, Kerala, India

Correspondence Address:
S Sheetal
16 FG, The Edge, Skyline Apartments, Thirumoolapuram, Thiruvalla - 689 115, Kerala
India

Abstract

The “heart sign” is a well-described radiological sign in bilateral medial medullary infarction, which is a rare stroke syndrome. It has also been rarely reported in infarction of bilateral paramedian pons and caudal paramedian midbrain. Bilateral brainstem infarcts usually present with varying degree of quadriparesis and in the initial stages, it is difficult to distinguish from other conditions such as Guillain–Barre syndrome and brainstem encephalitis. Recognizing the “heart sign” on magnetic resonance imaging in a stroke-like episode may be helpful in differentiating these conditions from bilateral brainstem infarcts.



How to cite this article:
Sheetal S, Kalliath A, Sasidharan A, Vijayalekshmi S. The utility of “heart sign” on neuroimaging in acute-onset quadriparesis: A series of three cases.Apollo Med 2021;18:212-214


How to cite this URL:
Sheetal S, Kalliath A, Sasidharan A, Vijayalekshmi S. The utility of “heart sign” on neuroimaging in acute-onset quadriparesis: A series of three cases. Apollo Med [serial online] 2021 [cited 2022 Jan 19 ];18:212-214
Available from: https://www.apollomedicine.org/text.asp?2021/18/3/212/324554


Full Text



 Introduction



Bilateral brainstem infarcts are rare stroke syndromes, with bilateral medial medullary infarction (MMI) accounting for <1% of all infarctions.[1] Bilateral medial pontine infarction (MPI) is also uncommon, occurring in <10% of all pontine infarctions.[2] The heart sign on magnetic resonance imaging (MRI) is a very useful radiological sign, well described in bilateral MMI and less commonly described in bilateral MPI and bilateral caudal midbrain infarction.[3],[4],[5],[6] However, it has been very rarely reported in bilateral pontomedullary junction infarcts.[7] Recognizing the “heart sign” on MRI in a stroke-like episode may be helpful in differentiating bilateral brainstem infarcts from other conditions such as Guillain–Barre syndrome and brainstem encephalitis.[3] We hereby report three cases, who presented with quadriparesis and were noted to have the “heart sign” on MRI brain, owing to infarction in bilateral medial medulla, pontomedullary junction, and pons.

 Case Reports



Case 1

A 70-year-old female with a history of type 2 diabetes mellitus, systemic hypertension, dyslipidemia presented with acute onset of weakness of all four limbs. She was found lying in the bed, by her daughter, in the morning. She was not speaking when spoken to but seemed to understand the queries. She was noted to be unable to move her limbs. She was offered water to drink, however, the water drooled out of her mouth. She was carried to the vehicle and brought to our hospital. On examination, she was conscious, was nodding to queries, and had dysarthria. Her pulse rate was 80/min and regular, and blood pressure was 160/90 mm Hg. Cranial nerve examination revealed gaze-evoked nystagmus, decreased movement of the tongue to either side, with difficulty in protrusion. Other cranial nerves were normal. Motor system examination revealed hypotonia of all limbs, with grade 2 power in all limbs. All deep tendon reflexes were sluggish, with bilateral extensor plantar response. Sensory system examination was normal. Few hours later, she developed breathing difficulty and was intubated and ventilated. MRI brain taken on a 1.5 T machine revealed a heart shaped hyperintensity in bilateral anteromedial medulla on diffusion weighted sequence, with low values on ADC – the characteristic “heart sign” [Figure 1]a and [Figure 1]b. MR angiography was normal [Figure 1]c. Hence, the diagnosis of bilateral MMI was made. She remained on the ventilator for the next 5 days, thereafter she underwent tracheostomy. She was discharged after 2 weeks, on tracheostomy, as her bystanders wished for home care.{Figure 1}

Case 2

A 78-year-old male with a history of type 2 diabetes mellitus and peripheral vascular occlusive disease presented with acute onset of dizziness, slurring of speech, and weakness of the right upper and lower limbs. On the next day, he developed weakness of the left upper and lower limbs also. On examination, he was conscious, obeying commands but had dysarthria and dysphonia. His pulse rate was 88/min and blood pressure was 150/90 mmHg. Examination of cranial nerves was notable for horizontal gaze-evoked nystagmus, left lower motor neuron type facial palsy, and bilateral lower motor neuron type hypoglossal palsy. On motor system examination, he had grade 3 power in all four limbs, with hyperreflexia and extensor plantar. MRI brain was taken which showed a heart-shaped diffusion restriction in bilateral pontomedullary junction, in the midline-the heart sign [Figure 2]a, [Figure 2]b, [Figure 2]c. MR angiography revealed normal caliber of the vertebral and basilar arteries [Figure 2]d. Over the next few days, his weakness progressed further and he was totally unable to move his limbs. He developed profuse pooling of secretions in the throat, and hence, he was intubated and ventilated. However, he deteriorated and 2 days later, when into a cardiac arrest from which he could not be revived.{Figure 2}

Case 3

A 65-year-old female, with a history of type 2 diabetes mellitus and systemic hypertension, presented with acute onset of slurring of speech and weakness of all 4 limbs. On examination, she was conscious and oriented, dysarthric and had emotional incontinence. She had difficulty in swallowing and was started on Ryle's tube feeds. Her pulse rate was 80/min and blood pressure was 160/90 mmHg. Cranial nerve examination was remarkable for pseudobulbar palsy, evidenced by a brisk gag reflex. Motor system examination revealed hypotonia and grade 3 power of all limbs, with bilaterally brisk tendon jerks and bilateral extensor plantar. MRI brain showed a large heart-shaped area of diffusion restriction in bilateral medial pons, suggestive of acute infarct [Figure 3]a and [Figure 3]b. MR angiography showed diffuse atherosclerotic changes in the basilar artery [Figure 3]c. Over the next 1 week, her dysarthria improved, she started taking oral feeds and was able to walk with support.{Figure 3}

 Discussion



The “heart sign” is a well-described radiological sign in bilateral brainstem infarcts. It is most commonly described with bilateral MMI. Bilateral MMI is a rare stroke syndrome, with accounting for <1% of all infarctions.[1] The medulla can be divided into four territories: anteromedial territory, anterolateral territory, lateral territory, and posterior territory, based on the vascular supply.[3] The heart sign is described in infarcts involving the anteromedial (supplied by branches of vertebral artery and anterior spinal artery) and anterolateral (supplied by short and long transverse branches of vertebral artery) territories of the medulla. MR angiography may be normal, pointing toward small vessel disease of the paramedian perforators from vertebral or anterior spinal arteries, as was seen in our first patient.[3],[4] Patients with bilateral MMI present acutely or subacutely with dysarthria, dysphagia, and quadriplegia and often have a poor prognosis.[1]

Bilateral MPI is also a rare syndrome and the clinical features may include quadriparesis, acute pseudobulbar palsy, or locked-in syndrome.[2] The vascular supply of the pons is by the paramedian arteries supplying the anteromedial territory, the short circumferential branches supplying the anterolateral territory, and the long circumferential branches, supplying the lateral territory. The heart appearance on imaging occurs in bilateral anteromedial and anterolateral arterial territories infarction.[5] This may happen with atherothrombotic disease of the basilar artery, as was seen in our patient. An extensive PubMed search revealed that there has been only a single case report of the heart sign in pontomedullary infarction, reported by Zhou et al.[7] They observed that it resulted due to infarction of the deep perforating branch and short circumflex branch of basilar artery. In our patient also, MRA was normal, and hence, the perforating branches of the basilar artery were possibly involved. One of the differentials for bilateral pontine T2 hyperintensities is osmotic demyelination, characterized by symmetric, central pontine, trident-shaped, T2-hyperintense lesions – the “trident sign.” However, diffusion restriction is reported in <50% cases of osmotic demyelination.[8] The presence of the “heart sign” on MRI can help in differentiating brainstem infarcts from other causes of quadriparesis such as Guillain–Barre syndrome, brainstem encephalitis, and periodic paralysis.[3]

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Bassetti C, Bogousslavsky J, Mattle H, Bernasconi A. Medial medullary stroke: Report of seven patients and review of the literature. Neurology 1997;48:882-90.
2Kumral E, Bayülkem G, Evyapan D. Clinical spectrum of pontine infarction. Clinical-MRI correlations. J Neurol 2002;249:1659-70.
3Sajan S, Thomas R. Heart sign in neurology – A radiological sign. NJNS 2020;17:120-2.
4Krishnan M, Rajan P, Kesavdas C, Iyer RS. The 'heart appearance' sign in MRI in bilateral medial medullary infarction. Postgrad Med J 2011;87:156-7.
5Venkatesan P, Balakrishnan R, Ramadoss K, Iyer RS. Heart appearance sign in pontine stroke: A result of bilateral infarction due to small vessel disease. Neurol India 2014;62:115-6.
6Zhou C, He Y, Chao Z, Zhu Y, Wang P, Wang X, et al. Wernekink commissure syndrome secondary to bilateral caudal paramedian midbrain infarction presenting with a unique “Heart or V” appearance sign: Case report and review of the literature. Front Neurol 2017;8:376.
7Zhou ZH, Wu YF, Wu WF, Liu AQ, Yu QY, Peng ZX, et al. Giant “heart appearance-like sign” on MRI in bilateral ponto-medullary junction infraction: Case report. BMC Neurol 2020;20:107.
8Beh SC. Temporal evolution of the trident and piglet signs of osmotic demyelination syndrome. J Neurol Sci 2017;373:268-73.