Intrauterine Herpes Simplex Virus Infection Presenting With Fetal Sinus Bradycardia and Pericardial Effusion: A Case Report.

Cardiac complications have rarely been reported in intrauterine herpes simplex virus (HSV) infection. We report a case of myocarditis associated with intrauterine HSV infection. Our patient's mother was a 28-year-old woman with no known history of HSV infection. Fetal ultrasound at 26 weeks of gestation revealed sinus bradycardia and pericardial effusion. Cesarean section was performed due to placental abruption at 28 weeks of gestation. A male newborn was born with extensive skin erosions, hypotension, and persistent bradycardia unresponsive to resuscitation. Despite intensive treatment, he died within 24 hours of life. Postmortem computed tomography revealed multiple calcifications in the heart wall, suggesting the existence of myocarditis. HSV-2 was confirmed in skin exudates by viral culture, and the diagnosis of disseminated HSV infection was made. Intrauterine HSV infection can be associated with cardiac complications. Clinicians should be aware of the possibility of HSV infection when encountering fetuses with the signs of myocarditis.