Chiari network: a case report

The Chiari network is a reticulated network originating from the inferior vena cava valve. Its incidence is observed to be about 2% in the general population.

In our instance, in a specimen observed during routine dissection, a fenestrated network of fibrous threads was attached to the inferior vena cava valve and the crista terminalis, sparing the coronary sinus valve and was identified as the Chiari network. Although clinically insignificant, the Chiari network is associated with various cardiac events including bundle branch blocks and ventricular and atrial arrythmias. It is also observed that the Chiari network is involved in the entrapment of guide wires inserted for interventions like cardiac catheterization and radiofrequency ablation procedure. Contrary to that, it is found to cause entrapment of thrombus preventing catastrophic massive pulmonary embolism. Transoesophageal echocardiography is considered as the best method to diagnose Chiari network.

Chiari network is remnant of the sinus venosus which is usually found incidentally during echocardiography or dissections or during autopsy procedures. It may be associated with various cardiac pathologies.