An unusual cause of a complete heart block in a young healthy man! (a case report).

Acute myocarditis represents a challenging diagnosis as there is no pathognomonic clinical presentation. It is rare to see heart block as the first-and-only presentation of infectious myocarditis. We report the case of a young healthy patient who presented with syncope secondary to a complete heart block. It was caused by acute presumed viral myocarditis. The diagnosis was confirmed with cardiac magnetic resonance imaging. With close monitoring, the EKG abnormalities resolved over the following 5 days. In this case report, we present the importance of several imaging tools to diagnose a rare and reversible cause of conduction disturbances. In at-risk individuals, clinicians should rule out a treatable cause of heart block before proceeding with permanent pacemaker implantation due to enormous clinical and cost implications involved.

A case of complete heart block in a patient with HIV and leptospirosis.

A 32 year-old patient presented with a two-week duration of fever with hepato-splenomegaly with dizziness spells for two days. The patient was found to have HIV and to be leptospira positive. Electrocardiogram showed complete heart block which disappeared after antibiotic treatment. Our case is unique because a combination of HIV, leptospirosis and complete heart block has never before been described in literature.

Atypical manifestations of congenital parvovirus B19 infection.

Parvovirus B19 infection in pregnancy is associated with fetal anemia, hydrops and fetal death. We report two unusual manifestations of vertical parvovirus B19 infection. The first patient developed hydrops as consequence of myocarditis with involvement of sino-atrial node. The other had pleural effusion reactive to the hepatic localization of the virus.

Relevance of inflammatory cell infiltrates for complete atrioventricular block in experimental murine myocarditis.

BACKGROUND: There are few systemic pathologic studies on myocarditis. This study aimed to clarify the pathologic characteristics of murine myocarditis. METHODS: We recorded serial electrocardiograms in experimental viral myocarditis in mice and then examined their cardiac pathology. After taking baseline electrocardiograms, we inoculated the mice intraperitoneally with the encephalomyocarditis virus. Electrocardiograms were serially recorded until 220 days after the virus inoculation. RESULTS: Serial electrocardiograms revealed ectopic beats, low voltage of the QRS complex, and the appearance of complete atrioventricular (AV) block. Corresponding myocardial lesions were found in the hearts of mice with these ectopic beats. Mononuclear cell infiltrations into the His bundle were most frequently found in mice with complete AV block. CONCLUSIONS: Inflammatory change with cellular infiltrations was the most common pathologic finding in mice with complete AV block. In clinical settings, anti-inflammatory therapy might be recommended for patients with myocarditis complicated with conduction disturbances.

Complete atrioventricular block in experimental murine myocarditis.

BACKGROUND: There were few reports on the pathological characteristics of the conduction system in myocarditis. This study was aimed to clarify the pathological characteristics of complete atrioventricular (AV) block in myocarditis. METHODS AND RESULTS: We studied serial electrocardiograms in experimental myocarditis in mice and also examined their cardiac pathology. After taking baseline electrocardiograms, mice were inoculated intraperitoneally with the encephalomyocarditis virus. Electrocardiograms were serially recorded until day 360. Serial electrocardiograms revealed the appearance of complete AV block. Myocardial lesions were found in the hearts of mice with these ectopic beats. Mononuclear cell infiltrations into the His bundle and necrotic lesions of the conduction system were found in 10.7% (18/168) of mice with complete AV block. However, 17.3% (29/168) of mice showed no evident pathological lesions except the edematous changes of AV node. CONCLUSIONS: The appearance of complete AV block in myocarditis may suggest not only significantly comparable pathological lesions of the conduction system but also the trivial edematous changes; in clinical settings, in the former case, permanent pacing therapy is necessary, and in the latter case, the disease may be transient and could be recovered from complete AV block. This study may shed light on the pathological characteristics of complete AV block in myocarditis.

[Syncope in 3rd degree atrioventricular block. Detection of virus genome in the myocardium]. / Synkope bei AV-Block III(o). Nachweis von Virusgenom im Myokard.

HISTORY AND CLINICAL FINDINGS: A 28-year-old woman was admitted after syncope which had been preceded by several flulike episodes. There was no history of any other serious disease. Physical examination was unremarkable. Heart sounds were regular and normal, there were no murmurs. INVESTIGATIONS: White cell count was 9400/microliter, with a normal differential count. Erythrocyte sedimentation rate and C-reactive protein were also normal. Virus serology revealed no abnormality. The electrocardiogram (ECG) showed complete (third degree) atrioventricular (AV) block with an idioventricular rhythm of 38 beats/min and right bundle branch block pattern. TREATMENT AND COURSE: A temporary transvenous pacemaker was inserted on the first hospital day. As myocarditis was suspected a right ventricular endomyocardial biopsy was obtained. Histological and immunohistological examinations demonstrated no unequivocal findings. But molecular-biological tests revealed. Coxsackie-B3 virus genome. The pacemaker was removed on the 6th day, when the ECG had shown intermittent second degree AV block. Regular sinus rhythm with a PR interval of 0.18 s was recorded on day 12, and 24-hour ECG monitoring for several days until her discharge on the 18th day confirmed this rhythm throughout. CONCLUSION: In aetiologically undetermined disease molecular-biological techniques can be indispensable for the exact diagnosis and may be decisive for administering specific treatment.

The expression of human endogenous retrovirus-3 in fetal cardiac tissue and antibodies in congenital heart block.

Endogenous retrovirus-3 (ERV-3) is an endogenous retrovirus encoding an open reading frame for an envelope protein expressed in placenta. In this study we also found high levels of expression in fetal heart, with peak expression occurring between 11 and 17 weeks of gestation. Antibodies to a peptide corresponding to a predicted epitope of ERV-3 were studied by ELISA in sera from 32 healthy women, 47 women during pregnancy, 19 post-partum, 34 with Sjogren's syndrome (SS), 28 with systemic lupus erythematosus (SLE) and 48 mothers of babies with congenital heart block (CHB). Elevated levels of antibodies to ERV-3 were found in normal pregnancy and in patients with SS or SLE. Compared with normal sera the highest levels occurred in mothers of CHB babies (P < 0.001). Antibodies from sera from three CHB mothers bound to recombinant transmembrane protein of ERV-3 on immunoblots, and to sections of fetal cardiac tissue and placenta. This study has shown evidence of autoimmunization to ERV-3 during pregnancy, with particularly high levels of antibodies in mothers of CHB babies. The expression of ERV-3 in fetal heart and the presence of antibodies in maternal sera suggest a possible role in the pathogenesis of CHB.