Chiari Network Endocarditis: Not Just an Innocent Bystander

Three-dimensional echocardiographic assessment of Chiari’s network relationship with the left ventricular false tendon

Background

Left ventricular false tendon (LVFT) is a fibromuscular band crossing the left ventricular cavity. And Chiari’s network (CN) is a highly mobile, mesh-like, echogenic structure in right atrium. In this study, we aimed to evaluate the coexistence of LVFT in patients with CN. CN patients were examined with live/real-time three-dimensional transthoracic echocardiography (TTE) for visualization of LVFT.

Results

This is a single-center prospective study of 49 patients with CN. In literature studies, the average ratios of LVFT were 22% in the normal population. In our study, an increased ratio of LVFT (n = 31, 63.3%) was found in CN patients evaluated with a three-dimensional TTE (63.3% versus 22%) (p = 0.01). The interatrial septal aneurysm was found in 31 (63.3%) patients with CN. And, the positive contrast echocardiography examination was determined in 22 (61.1%) patients with CN.

Conclusions

Our study reveals that CN is associated with LVFT and is also associated with cardiac anomalies like an interatrial septal aneurysm, and atrial septal defect. And LVFT can be evaluated better with three-dimensional TTE than with traditional two-dimensional TTE. Patients with CN should be evaluated more carefully by three-dimensional echocardiography as they can be in synergy in terms of the cardiac pathologies they accompany.

Supplementary Information

The online version contains supplementary material available at 10.1186/s43044-022-00287-5.

Chiari network diagnosis intraoperative based on echocardiography

We report a case of a Chiari network as a possible cause of intraoperative supraventricular tachycardia with potential cardiac flow obstruction and hemodynamic collapse. The intraoperative diagnostic analysis considered detects cardiac abnormalities associated to this congenital remnant and discard common intraoperative causes of hemodynamic alterations.

Chiari network diagnosis intraoperative based on echocardiography

We report a case of a Chiari network as a possible cause of intraoperative supraventricular tachycardia with potential cardiac flow obstruction and hemodynamic collapse. The intraoperative diagnostic analysis considered detects cardiac abnormalities associated to this congenital remnant and discard common intraoperative causes of hemodynamic alterations.

Chiari Network or Catheter-Associated Thrombus? A Rare Complication of Transseptal Access

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Chiari network dragged into the left atrium during left atrial appendage occlusion.

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Chiari network initially confused for thrombus adherent to the transseptal catheter.

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This case highlights a unique complication likely to recur.

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This case provides direction should this situation be encountered again.

Complicated Infective Endocarditis Limited to a Chiari Network

Introduction

The Chiari network is an uncommon vestigial structure of the heart that is often clinically insignificant. We present an unusual case of infective endocarditis affecting only the Chiari network in a patient who presented with septic emboli to the lungs and brain.

Case summary

A 61-year-old man was admitted with a 2-month history of hemoptysis, pleuritic chest pain, and right upper extremity numbness and weakness. He was found to have multifocal bilateral pulmonary opacities and an abscess collection in the brain. Blood cultures grew Streptococcus intermedius and transthoracic echocardiogram (TTE) was normal. Subsequent transesophageal echocardiogram (TEE) revealed an 8.3 × 4.6 mm vegetation arising from the Chiari network, close to the right atrial appendage, without involvement of the tricuspid valve or any of the other valves. There were no atrial or ventricular septal defects. He was treated with appropriate antibiotics with improvement of symptoms. Repeat imaging showed improvement of the lung opacities, but not the brain abscess, warranting transfer to another hospital for neurosurgical intervention.

Conclusion

The diagnosis and management of isolated Chiari network endocarditis require a high index of clinical suspicion. A multidisciplinary approach incorporating both medical and surgical approaches where necessary is essential for optimal outcome.

The Chiari Network-Only an Embryonic Remnant or a Confusing Finding?

Chiari network is an embryonic remnant of valves of the sinus venosus, which can be observed in several locations in the right atrium. Although it is usually considered a normal anatomic variant, when associated with certain clinical conditions, the Chiari network may become a confusing finding, and a careful differential diagnosis is required. It should be differentiated from a tricuspid valve disruption, vegetation, thrombus, or tumoral mass. In this case report, we describe a singular case of endocarditis over a Chiari network in a seven-year-old boy that was successfully managed in a conservative fashion.

The Presence of a Large Chiari Network in a Patient with Atrial Fibrillation and Stroke

The Chiari network is an embryological remnant found in the right atrium, mostly without any significant pathophysiological consequences. However, several cardiac associations are reported in the literature including supraventricular tachyarrhythmias. We present a case of a 96-year-old body donor with a stroke episode and intermittent atrial fibrillations. The dissection of the heart revealed the presence of an immense Chiari network with a large central thrombus. The role of a Chiari network in the pathogenesis of stroke and pulmonary embolism is discussed.

Chiari network: A case report and brief overview

The Chiari network is mobile, net-like structures occasionally seen in right atrium near the opening of inferior vena cava and coronary sinus. This is usually of no clinical significance and is often diagnosed incidentally. However, sometimes it may cause diagnostic confusion with right atrial pathologies, and may favour thromboembolism by causing flow obstruction. It may be associated with infective endocarditis, arrhythmias, and migraine. Sometimes, it acts as a physical barrier during invasive procedures. The Chiari network has also been described to protect from pulmonary embolism by acting as an inferior vena cava filter due to its sieve-like effect at the cavo-atrial junction. Here, the Chiari network has been described in a case of Ebstein anomaly of tricuspid valve which produced diagnostic confusion during echocardiography. A brief overview has also been presented.