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We report a case of Miller Fisher syndrome associated with reversible left ventricular wall motion abnormalities similar to takotsubo shaped cardiomyopathy.
Case report
A 58 year old man was admitted to our hospital because of ataxia, ophthalmoplegia, and dysarthria. He had a 10 year history of hypertension. Four weeks before admission, he had common-cold-like symptoms. Ten days before admission, he developed difficulties with walking and speaking. The next day he was unable to walk or lift his eyelids. He was admitted to another hospital, where he was diagnosed as having a brain stem infarct. During admission, he developed tightness in the chest for three to four days which improved spontaneously. Because of exacerbation of his neurological symptoms, he was transferred to our hospital.
On initial physical examination, his blood pressure was 158/106 mm Hg and his heart rate was 108 beats/min and in regular rhythm. He was afebrile and had no respiratory difficulty. On neurological examination, he was fully orientated. His pupils were slightly mydriatic bilaterally (right 6 mm, left 6.5 mm) and the light reflex was absent on both sides. Complete ophthalmoplegia and peripheral facial palsy were observed bilaterally. He had severe dysarthria with restricted movements of the soft palate and tongue. Although muscle strength was preserved, deep tendon reflexes were absent in the four extremities. The plantar responses were flexor. There was no definite involvement of sensory disturbance. Ataxia was observed in the four extremities.
Routine laboratory tests were normal except for a slightly increased white blood cell count. Cerebrospinal fluid obtained on the first hospital day showed one monocyte per high power field and an increased protein level of 82 mg/dl. Aetiological investigations, including anti-GM1, anti-GM2, anti-GD1a, anti-GM1b, anti-GT1a, anti-GQ1b, anti-GD1b, anti-GT1b titres, were all negative. Results of thyroid function tests, angiotensin converting enzyme level, c-ANCA, p-ANCA, anti-acetylcholine receptor antibody, serum electroimmunophoresis, and polymerase chain reaction analysis for CSF tuberculosis and herpes simplex virus were all normal. Serum titres of influenza A and B, measles, mumps, varicella-zoster virus, cytomegalovirus, Epstein–Barr virus, herpes simplex virus, rubella, and mycoplasma were also normal. Cranial magnetic resonance (MR) imaging and MR angiography showed no abnormal lesions. EEG findings were normal. Nerve conduction studies showed decreased F wave persistence in the arms. Motor and sensory nerve conduction velocities were well mintained.
On the basis of the neurological findings, we established a diagnosis of the Miller Fisher syndrome. The patient was treated with a 12 litre plasma exchange over six days, followed by high dose intravenous gamma globulin (400 mg/kg/day for five continuous days).
There was no chest pain during admission to our hospital; however, an ECG on the first hospital day showed sinus tachycardia with slightly elevated ST segments in leads V3–V5. T waves were inverted in leads I, II, aVL, and V3–6 on the fifth day. These findings, in conjunction with the pevious episode of chest tightness, led us to suspect acute coronary syndrome, and we undertook coronary angiography. Although the coronary arteries were free of any lesions, a left ventriculogram showed severe hypokinesis in the anterolateral, apical, and diaphragmatic segments, with an ejection fraction of 34%. Provocative vasospasm was not confirmed. Maximum creatine kinase MB release was 8.0 ng/ml (normal < 5.0 ng/ml). A left ventriculogram on the 13th hospital day showed an improvement in the hypokinesis, with an ejection fraction of 44%. There were no specific abnormal findings on myocardial biopsy. Serum noradrenaline (norepinephrine) concentrations were increased to 810 ng/l, 1160 ng/l, and 549 ng/l on the seventh, 14th, and 78th day, respectively (normal 90–420 ng/l). Thallium-201 scintigraphy on the ninth day showed only mild hypoperfusion in the lateral wall; however, I123-metaiodobenzylguanidine (MIBG) scintigraphy done on the 12th day revealed a decrease in uptake in the anterior, inferior, and lateral walls in the early phase (fig 1A). MIBG scintigraphy on the 70th day showed improved uptake (fig 1B). The patient was discharged on the 130th day with marked improvement in both ophthalmoplegia and gait disturbance.
MIBG (metaiodobenzylguanidine) myocardial scintigrams on the 12th day (A) and the 70th day (B). On the 12th day, MIBG uptake was reduced in the anterior, inferior, and lateral walls (A). The uptake had recovered by the 70th day (B).
Comment
In this case, serum anti-GQ1b antibody was negative despite its common association with Miller Fisher syndrome. However, we feel that the triad of ataxia, areflexia, and ophthalmoplegia in association with dissociation of protein and cytological findings in the CSF and the absence of specific findings on cranial MR imaging and MR angiography is sufficient to justify our diagnosis of the Miller Fisher syndrome. Autonomic dysfunctions consisting of sinus tachycardia, increased serum noradrenaline, and decreased MIBG uptake were noted in this case. As these dysfunctions were reversible and paralleled the severity of the Miller Fisher syndrome, they probably have the same aetiology. Because I123-metaiodobenzylguanidine is a physiological analogue of noradrenaline, and is actively transported into the noradrenaline granules of sympathetic nerve terminals by uptake-1, decreased MIBG uptake in the early phase suggested the involvement of cardiac autonomic nerves. Normal findings on coronary angiography, as well as unremarkable findings on thallium-201 scintigraphy, ruled out ischaemic cardiomyopathy. Thus autonomic dysfunction in the cardiovascular system was considered to have been an important factor in the present case.
Takotsubo shaped cardiomyopathy is a unique heart syndrome characterised by reversible left ventricular apical wall motion abnormalities with chest symptoms, ECG changes, and minimal myocardial enzymatic release mimicking acute myocardial infarction without coronary stenosis.1,2 The syndrome is named “takotsubo shaped” cardiomyopathy as it has often been reported in Japan and the unique configuration of left ventriculogram resembles a takotsubo, a Japanese word describing an octopus pot.2 The left ventricular wall motion abnormality observed in the present case can be included in the takotsubo shaped cardiomyopathy category because of its reversible course and other clinical characteristics. Although the detailed aetiology of this syndrome remains unclear, enhanced sympathetic activity or vasospasm are considered to play a role in the development of contraction abnormalities.1 Three cases of Guillain-Barré syndrome with reversible left ventricular dysfunction have previously been reported.3–5 In all these cases, the apical regions were mainly involved. In two of the three cases, MIBG scintigraphy was done and showed decreased uptake around the apex in both cases.3,4
To our knowledge, this is the first report of a case of Miller Fisher syndrome with reversible cardiomyopathy caused by impairment of the autonomic nervous system. This cardiac syndrome may easily be missed because of its transient nature, with minimal abnormalities on routine laboratory findings. However, careful cardiac examination including ECG, left ventriculography, and MIBG scintigraphy may lead to the identification of further cases of Miller Fisher syndrome showing this cardiac complication.