The role of Chiari`s network in cardiovascular pathology

Introduction: The Chiari network, encountered infrequently in the right atrium, is a fenestrated, net-like embryonic remnant of the right valve of sinus venosus, lying closely in relation to the inferior vena cava and coronary sinus, sometimes connecting these with other right atrial structures. It is believed to be of little clinical significance. Aim: The aim of this work is to discuss the role of Chiari`s network in various cardiovascular pathologies.Material and methods: The Chiari network results from failure of resorption of the right sided sinus venosus valve. Developmentally, the right valve of sinus venosus evolves into two valves: the valve of the inferior vena cava (Eustachian valve) and the valve of the coronary sinus (Thebesian valve). During involution of these valves, tissue undergoes fenestration so that a network may be formed from remnants that usually disappear. The prevalence of Chiari network has been reported to be variable 2-13.6%. However, numerous researches have shown that this remnant is frequently associated with different cardiovascular pathologies such as patent foramen ovale, atrial septal aneurysm, paroxysmal arterial embolic events etc.Results: The most recent researches have shown that although Chiari`s network is in some cases associated with other pathological findings, these combinations may be merely coincidental. It has been reported to be involved in the pathogenesis of thromboembolic disease, endocarditis, arrhythmias, and entrapment of catheters upon percutaneous intervention.Conclusion: In conclusion, nowadays  Chiari`s network is regarded a benign and normal anatomic variant that is rarely of clinical importance. It is overall an uncommon diagnosis and plays a role only as long as it concerns diagnostics, because if not recognized appropriately it may lead to misdiagnosis.