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Miguel Bayones
Dilated cardiomyopathy in polymyositis
ability to perform daily activities like walking and stair
climbing. Concomitantly, the patient presents with moderate
myalgia that was unresponsive to NSAIDS. Due to persistent
symptomatology, the patient is admitted to the Bejuma District
Hospital in October of 1991, where the patient is evaluated
for 21 days. Electromyography, skeletal muscle biopsies,
and further lab tests were performed; posing a diagnostic
impression of Polymyositis. The results showed a CPK ( 1435
IU/L) and CK-MB (40 IU/L) elevation, electromyography of
the anterior tibial, left vastus medialis, right deltoid, right
quadriceps, right long supinator and left gastronecmius
reported myopathic affection with proximal musculature
predominance. After the analysis of these results, specialists
concluded the diagnosis of Polymyositis. Oral Prednisone is
indicated for 15 days. A Rheumatology service consultation
is also requested. The patient did not follow treatment nor
attended to the Rheumatologist evaluation.
In March of 2007, he returned to the center after
complaining of respiratory distress during mild efforts,
concomitantly non-productive cough and palpitations, which
is why he was evaluated and admitted for 7 days. Physical
examination showed: Patient in regular general conditions.
Temperature: 36.5 ° C. Pulse: 100 b.p.m. Breathing: 20 b.p.m.
Blood Pressure: 100 / 70mmHg. Hydrated skin without
apparent lesions. Symmetric thorax, apex visible and palpable
in 7th left intercostal space at 3cm outside of left midclavicular
line, tachyarrhythmic cardiac sounds with holosystolic murmur
grade II; Respiratory sounds present in both hemithorax with
crackles in both pulmonary bases. Limbs showed decreased
muscle strength in both upper limbs and mainly in lower
limbs in its proximal portion, manifested by limitation to gait
and incorporation in squatting position, muscular atrophy is
evidenced at the predominance of bilateral femoral region,
preserved osteotendinous reflexes, superficial and deep
sensitivity conserved, no varices or edema are evident. Rest
of the physical evaluation, without alterations. Machado
Guerreiro test was negative, EKG showed Left Bundle Branch
Blockade with Ventricular Extrasystoles, in the chest X-ray
bibasal infiltrate, dilated cardiomyopathy is observed, and
echocardiogram indicated dilated cardiomyopathy in four
wells, left ventricular systolic function severely depressed with
Ejection Fraction (EF) of 17% moderate mitral insufficiency,
mild tricuspid insufficiency, without intracavitary thrombi.
The patient is diagnosed with functional class III dilated
cardiomyopathy.
After 7 days of hospitalizations the patient was discharged
with Prednisolone P.O (1g/day) and medical treatment for
cardiac insufficiency (lisinopril 2.5mg/day, spironolactone
5mg/day, metoprolol 25mg/day).
DISCUSSION
Polymyositis is an idiopathic inflammatory disease whose
prevalence is estimated in one case per 100,000 inhabitants
per year in the general population and an incidence of 5 to
10 cases per million in adults. The highest incidence occurs
around the fifth decade of life and the woman / man ratio is
2: 1 (3,7). Being a disease of unusual appearance it is often
considered by many specialists as a diagnosis of exclusion (1).
The factors that trigger polymyositis are still unknown.
The theory of a viral cause such as Coxsackie virus, influenza
virus and HIV infection has been proposed, the latter being the
most accepted because of the development of inflammatory
myopathies in patients infected with a retrovirus. However,
several studies have yielded conflicting results. Likewise, the
effect of genetic factors and environmental agents has been
hypothesized (1, 4). Our patient wasn’t aware of the presence
of polymyositis in his family and also denied the history of a
viral infection. The ELISA test for HIV reported a negative result.
The etiopathogenesis of this disease is believed to have
an autoimmune basis. The presence of a direct cytotoxicity
phenomenon restricted to the expression of class 1 antigens
of the major histocompatibility complex has been evidenced.
Polymyositis as an isolated entity is rare; more commonly it
appears along with some other inflammatory disorder, being
denominated “overlap syndrome”. These include: mixed
connective tissue disease (MCTD), scleroderma myositis
overlap syndrome, and the antisynthetase syndrome. It is
common to see physical findings such as sclerodactyly and
Raynaud’s phenomenon (1,2,4). Due to institutional and
economical limitations, it was not possible to perform the
necessary laboratories for the detection of antibodies related
to these entities.
The diagnosis of inflammatory myositis is based on
the presence of at least 3 clinical and laboratory findings,
including: the presence of progressive weakness in the upper
and lower extremities, elevation of muscle enzymes such as
creatine kinase and transaminases, Electromyography and
abnormal muscle biopsy. The presence of suggestive results in
the aforementioned studies and the absence of dermatological
findings such as Gottron’s papules and heliotrope rash excluded
the possibility of a diagnosis of dermatomyositis (4,5). In our
case, it would be necessary to do a differential diagnosis
with Chagas disease, which can present peripheral muscle
alterations, in addition to the characteristic heart affection.
Due to its similar presentation, Chagas can be confused with
Polymyositis (6). A test of Machado Guerreiro was indicated,
which yielded negative results.
Among the various complications related to the diagnosis
of polymyositis, the most common is the development of
interstitial lung disease; which has been evidenced in almost
75% of the cases (7,8,9). Cardiovascular complications have
an approximated prevalence of 9 to 72% of cases (10) It has
been hypothesized suggested that the development of cardiac
complications are the sum of traditional cardiovascular
risk factors plus the characteristic systemic inflammation
in Polymyositis , which may explain the long period of time
before the onset of cardiac symptoms in our patient. Cardiac
symptomatology is often related to a bad prognosis in patients
with Polymyositis The progress to systolic heart failure, has been
documented in case reports, however, there are no controlled
studies exposing this complication (11).). The development of
cardiac insufficiency by cardiomyopathy tends to be observed
in patients with important peripheral musculature affection
(12,13). Electrocardiographic manifestations include branch
block, A-V block, prolonged PR interval, left ventricular
abnormalities, ventricular extrasystoles, high-grade cardiac
block, Q-wave abnormalities, and non-specific changes in the
ST segment (10).
Due to economical causes, in Venezuela we do not have
the steroids sparing immunotherapy medications for the
treatment of inflammatory myopathies.
With the presentation of this case report, we would
like to highlight the relevance of a proper patient education
and medical follow up, which are the keys in the prevention
of long term complications. Even thought, in the Venezuelan
public health system, we don’t always count with the necessary
diagnostic and therapeutic tools, we as physicians try to prioritize
the use of a good clinical eye and a complete medical history to
obtain the correct diagnosis give the best treatment option.
Acknowledgement:
Bejuma District Hospital Epidemiology
Service.