Case presentation
According to the SLICC 2012 criteria (13), a 15-year-old girl of African ethnicity was diagnosed with jSLE with a past history of Hashimoto’s thyroiditis treated by L-thyroxine presented with paroxysmal constructive chest pain, Exertional dyspnea, headache, and polyarthralgia. She also reported photosensitivity. On systemic review, the patient did not report either an upper airways infection preceding her complaints or any other associated general or specific symptom. Clinical examination revealed a fever of 39° C with blood pressure of 100/60 mmHg. There was no polypnea, no evidence of right heart failure, no audible murmur on cardiac auscultation, and no edema of the lower limbs. The biological analysis revealed a Leucopenia (3500/mm3), anemia (10g/dl), elevated erythrocyte sedimentation rate (ESR\1st h = 50 mm\h at the first hour, C-reactive protein (20 mg/l) and a direct Coombs test that was negative. Infections were excluded  with multiple negative blood cultures, as well as for anti-streptolysin O antibodies.  The immunological test revealed homogeneous anti-nuclear antibodies at 1/10,000 with the positivity of anti-native DNA antibodies (32 IU/ml) and anti-SSA antibodies. Antiphospholipid antibodies: anti cardiolipin anti beta 2 glycoprotein, were negative. The electrocardiogram showed sinus tachycardia, and the chest X-ray was free of cardiomegaly and pleural effusion. However, the transthoracic echocardiography has objectified a pericardidtis associated with a non-compacted LV, nodular thickenings of a few millimeters on the mitral valve with a small pericardial effusion. Thus, a cardiac magnetic resonance imaging (CMRI) was performed confirming the non-compaction of the LV with an hypertrabeculated sub-endocardium in the distal and apical regions (Figure 1, 2, and 3), with foci of fibrosis at the level of the cryptic fundus and a global hypokinesia of the LV. The systemic review did not reveal any proteinuria, hypocomplementemia or cerebral vasculitis on cerebral magnetic resonance imaging (MRI). Our patient was treated by high doses of corticosteroids (0,5mg/kg/j) associated with beta-blocker therapy with favourable outcome. The 2-year follow-up was characterized by a stabilized disease, without relapses on low dose corticosteroids.
DiscussionLVNC, also known as hypertrabeculation cardiomyopathy, or spongy myocardium, is currently a rare disease listed as an unclassified cardiomyopathy (CM) by the World Health Organization (WHO) (14) and the European Society of Cardiology (ESC) (15), and classified as a genetic CM by the American Heart Association (AHA) (16). The other proposed mechanism for the development of LVNC was acquired microcirculatory dysfunction leading to microinfarcts and hypertrabeculation. In addition, patients with chronically high preload or afterload, have a high prevalence of trabeculations and may also fulfill the criteria for LVNC (5,17).The reported incidence of LVNC is 0.05%, its prevalence is often underestimated and appears to be significantly higher in children than in adults (18). Cardiac involvement is certainly not uncommon in jSLE (19), with a prevalence of 50% (20). All three layers of the heart-pericardium, myocardium, and endocardium-can be affected by jSLE. Pericarditis is the most common cardiac manifestation of jSLE, occurring in up to 25% of patients (21). Clinical detection of myocarditis, which is the most characteristic feature of myocardial involvement in jSLE, ranges from 3% to 15% (22). In a study of children with primary CM of all types, LVNC was present in 9.2% of cases, making it the third most common type of primary CM after dilated CM and hypertrophic CM (23). LVNC is due to the failure of condensation of the myocardial spongy meshwork of fibers and intertrabecular recesses during intrauterine life leading to the persistence of ventricular trabeculations (24). Trabecular compaction occurs between 12 and 18 weeks of gestation, beginning at the base of the heart and progressing toward the apex (25). For unknown reasons, in patients with LVNC, this transition does not occur, resulting in the development of a thickened, noncompacted endomyocardial layer with prominent trabeculations that are continuous with the LV cavity and do not communicate with the epicardial circulation, deep recesses, and a thin, compacted epicardial layer (25). Approximately two-thirds of patients with LVNC may have NMDs (4), including myotonic dystrophies, dystrophinopathies, Charcot-Marie-Tooth disease, Barth syndrome, Friedreich’s ataxia, and Pompe disease (26). Thus, Patients with such NMDs should be screened promptly for CM (27). Men are more frequently affected by LVNC than women (28). LVNC is more prevalent in blacks (29) and that was the case of our patient who is a black ethnic background girl. This CM can occur at any age, ranging from early infancy to late adulthood or even remain completely asymptomatic, as shown by cases discovered accidentally (30). Median age at diagnosis is 40- 50 years in adults, and 5-7 years in pediatric patients (28, 31). The age at diagnosis in our patient was 15 years. The clinical presentation is highly variable, LVHT is usually diagnosed when the condition becomes symptomatic or when complications occur (32). Reasons for consultation include often unexplained heart failure, palpitations or exertional dyspnea, chest pain, or syncope (33). Such was the case with our patient, whose reason for consultation was chest pain with exertional dyspnea. Meanwhile, the classical triad of heart failure (HF), ventricular arrhythmias, and systemic embolism constitute typical complications of this disease (33). No electrical signs are specific for LVNC, but electrocardiograms (ECG) should be performed routinely in LVNC cases, as they can show rhythm and conduction disorders of varying severity, signs of myocardial hypertrophy, ST segment changes, bundle branch blocks or ventricular extrasystoles (34). The frequency of ECG abnormalities is high: 88% in pediatric patients (35). A sinus tachycardia was noted in our patient. Echocardiography, and CMRI are the gold standard tests for LVNC diagnosis (36). Transthoracic echocardiography (TTE), because of its simplicity, is the most commonly used technique. It shows the presence of criteria leading to the LVNC suspicion (37) such us: presence of multiple left ventricular trabeculations, presence of deep intertrabecular recesses, color doppler flow within the recesses and in communication with the LV cavity. Classically, when the ratio of non-compacted area to compacted area is greater than 2, LVNC diagnosis is made (38). In doubtful cases, CMRI provides similar diagnostic elements, allowing perfect visualization of the trabeculations and recesses as well as their localization ( 39). It confirm echographic findings, detect subtle patterns, assess myocardial damage level, obtain data on myocardial perfusion, assess myocardial fibrosis, identify ventricular thrombi, and distinguish between LVNC and other potential diagnoses (39). Real-time 3D echocardiography is another newly introduced method, which allows a more accurate quantification of the number of trabeculations and left ventricular mass (40). Our patient had both TTE and CMRI, and was diagnosed with LVNC by both methods. At present, no consensus for the diagnostic criteria for LVNC and the best diagnostic methods (32). Pathoanatomical findings currently seem to be the gold standard for diagnosing LVHT (41). Currently, there is no specific option for the LVNC treatment, which is the same as for HF ( 42). There are three main goals of treatment: treatment of HF, antiarrhythmic therapy, and antithrombotic therapy to prevent systemic embolism in patients with impaired LV function ( 33). The prognosis for patients with LVNC is extremely variable, ranging from a prolonged asymptomatic course to rapidly progressive HF, which may lead to heart transplantation or death. More recent publications, report a mortality rate ranging from 2% to 15% (3) with the highest risk of death associated with ventricular arrhythmias and HF (24). In 2007, a LVNC was reported in a patient with Behçet’s disease with multiple thrombus formations (43). Another patient with ankylosing spondylitis also had features of LVNC (44). Recently, a CM strongly resembling LVNC was described in a patient with proliferative lupus nephritis (45). Also, When reviewing literature, there are reports on association of LVNC with, endocrine abnormalities including hypothyroidism (46). The current case describes the features of LVNC in a patient with jSLE and Hashimoto’s thyroiditis. LVNC might represent more a morphologic expression of different underlying morbidities than a distinct CM, according to some group of authors (47). If these underlying disorders include jSLE and other connective tissue disorders, it is an open question.