Transient AV Block as a Hemodynamic Complication of the Influenza A Virus: A Case Report.

Influenza virus causes annual epidemics of respiratory illness characterized by sudden onset of fever, malaise, myalgias, headache, cough, and other respiratory complains. Each year in the United States, it is estimated that this debilitating respiratory illness accounts for 294,000 excess hospitalizations and 36,000 attributable deaths. Epidemiological studies describe increased cardiovascular mortality during influenza seasons. Cardiovascular involvement in acute influenza infection can occur through direct effects of the virus on the myocardium or through exacerbation of existing cardiovascular disease. The purpose of this report is to document a transient atrioventricular (AV) block with hemodynamic compromise after infection with the influenza virus in a patient with underlying cardiac disease without myocarditis.

Acute right ventricular myocarditis presenting with chest pain and syncope.

Myocarditis is assumed to involve both ventricles equally. Right ventricular predominant involvement is rarely described. A case of acute viral right ventricular myocarditis presenting with chest pain and syncope, grade 3 atrioventricular block, right ventricular dilatation and free wall hypokinesia is reported. Cardiac MRI showed late enhancement of the right ventricular free wall without involvement of the left ventricle. Anti-Coxsackie A9 virus neutralising IgM-type antibodies titre was elevated. This case emphasises that manifestations of myocarditis can be limited to the right ventricle and should be considered in the differential diagnosis of right ventricular enlargement.

Parvovirus-mediated fetal cardiomyopathy with atrioventricular nodal disease.

Acute parvovirus B19 infection (API) in pregnancy has been associated with fetal anemia and hydrops fetalis. Direct myocardial damage from API in a fetus and an infant has been described. This report presents a case of fetal second-degree heart block and cardiomyopathy secondary to API. A 19-year-old G4P1112 (gravida 4 para 2 with 1 term delivery, 1 preterm delivery, 1 termination, and 2 living children) was referred at 20 weeks gestation for fetal bradycardia. A 2:1 atrioventricular block was identified by fetal echocardiography at 23 weeks. Hydrops developed at 25 weeks. Amniocentesis and percutaneous umbilical blood sampling demonstrated API. At 31 weeks, the patient presented with preterm labor and delivered a viable female infant, who died of poor cardiac function and arrhythmia on the first day of life. In addition to fetal anemia and hydrops fetalis, API in pregnancy may cause direct fetal myocardial damage and conduction system disease.

A newborn with congenital complete atrioventricular block, lissencephaly, and skeletal abnormalities: a case of suspected cytomegalovirus infection.

We present a case of congenital complete atrioventricular block in a preterm microcephalic male with multiple additional congenital anomalies, including spinal and rib abnormalities. The heart was structurally normal, and maternal tests for autoimmune disorders were negative. The brain had an immature lissencephalic appearance, suggestive of an insult early in gestation. Genetic testing was normal, virtually excluding chromosomal disorders that are known to cause lissencephaly. Viral studies were suggestive of cytomegalovirus infection during early gestation, and we believe that the patient's clinical presentation was most likely the result of an early cytomegalovirus infection. The finding of complete atrioventricular block in a patient with presumed cytomegalovirus infection would represent a very rare complication. "Isolated" complete atrioventricular block in a fetus should be considered an incentive for an extensive work-up in search for a possible etiology, rather than accepted as a final diagnosis.