Toxocariasis-associated cardiac diseases—A systematic review of the literature

•Toxocariasis is a mostly oligo- or asymptomatic infection.•Toxocariasis may present with unusual complications.•Diagnosis is based on clinical presentation, eosinophilia and serological findings.•Toxocara spp. can cause endocarditis, myocarditis and pericarditis.•Tamponade, endocardial thrombosis or heart failure can complicate cardiac toxocariasis.•Severe disease may warrant prolonged treatment with albendazole and corticosteroids. Toxocariasis, caused by Toxocara canis or Toxocara catis, is a worldwide occurring parasitic disease, reaching high prevalences especially in tropical and subtropical countries. The clinical presentation can range from asymptomatic seropositivity to life threatenting disease, depending on the organ system involved. Cardiac involvement, one of the possible manifestations of human Toxocara spp. infection, is rarely reported in case reports. As far as we know, no systematic reviews of clinical presentations have been published till now and no clear recommendations regarding the treatment of Toxocara spp. infection involving the heart exist. In a systematic review of the literature, 24 published cases of Toxocara spp. infection involving the heart were identified. The cardiac entities described included myocarditis, pericarditis, and Loeffler’s endocarditis. The clinical presentation ranged from asymptomatic or mild disease to life threatening myocarditis/pericarditis with heart failure or cardiac tamponade, leading to death. In most cases, the diagnosis was based on a combination of clinical, laboratory and radiological findings. Only in three of the nine cases in which histological analysis was performed (either pre- or post-mortem), granulomas or remnants of the parasite were detected. In the other six cases, findings were non-specific; the damage of the heart was equally caused by direct invasion of the larvae and by immunological reactions, either caused by the systemic hypereosinophilia or by the presence of the larvae in the tissue. The treatment regimen described mostly consisted of anthelmintic drugs in combination with corticosteroids. Even though dosage and duration of treatment varied widely, ranging from days to months, most patients were treated successfully. Cardiac involvement in Toxocara spp. infection is a rare but potentially life-threatening complication of a very common disease. The therapeutic regimens vary widely especially with regard to the duration of therapy, however, the combination of an anthelmintic d