Crimean-Congo hemorrhagic fever: does it involve the heart?

Summary 

Objective

Crimean-Congo hemorrhagic fever (CCHF) is an acute viral hemorrhagic fever with a high mortality rate. Despite increasing knowledge about viral hemorrhagic fevers, the pathogenesis of CCHF and causes of death have not been well described. In this study, we aimed to evaluate the cardiac functions of CCHF patients.

Methods

This prospective study was performed among confirmed CCHF cases in Turkey in 2007. All the patients underwent a thorough cardiologic evaluation and transthoracic echocardiography examination within 24hours of hospitalization. In addition, the patients were classified into two groups – ‘severe’ CCHF and ‘non-severe’ CCHF. Demographic characteristics, findings of echocardiography, and outcomes were recorded for each patient.

Results

Among 52 consecutive patients with a tentative diagnosis of CCHF, 44 were confirmed as having CCHF. Seventeen (38.6%) patients were classified as severe, whereas the remaining 27 (61.4%) patients were classified as non-severe. Five of 17 severe CCHF patients died. Severe cases had a lower left ventricular ejection fraction (p=0.04), a higher systolic pulmonary artery pressure (p=0.02), and more frequent pericardial effusion (p<0.001) compared to non-severe cases. Fatal CCHF cases also had a lower left ventricular ejection fraction (p=0.03), a higher systolic pulmonary artery pressure (p=0.03), and more frequent pericardial effusion (p=0.01) compared to survivors.

Conclusions

The results of this study indicate that severe and fatal CCHF cases have impaired cardiac functions, which may be associated with fatality in CCHF infection. Direct invasion of the heart muscles by the virus or endothelial damage of cardiac structures may have a role in this. Molecular testing methods would be useful in order to investigate direct invasion by the CCHF virus. Clinicians should be aware of this complication.

Keywords: Crimean-Congo hemorrhagic fever, Echocardiography, Cardiac functions