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Published on: February 8, 2022
Right Atrial Septal In Situ Microthrombus: A Potential Novel Cause of Patent Foramen Ovale-Associated Stroke
Jianbo Zhu1,2, Anni Chen1,2,3, Lei Zhu1,2
1Department of Echocardiography Shaoxing People's Hospital Shaoxing China.
Background:
Patent foramen ovale (PFO)-associated stroke has a complex and diverse pathogenesis. It mainly results from a paradoxical embolism caused by venous thrombosis. However, few studies have investigated the presence of an in situ thrombus in the right atrium. Transesophageal echocardiography can effectively detect right atrial septal in situ microthrombus. Therefore, we aimed to explore the relationship between a right atrial septal in situ microthrombus and PFO-associated stroke and further dissect the pathophysiological basis of microthrombus formation.
Methods And Results:
Between April 2022 and October 2023, we prospectively investigated 466 patients who visited our hospital for transesophageal echocardiography with a high clinical suspicion of PFO. Right atrial septal in situ microthrombus was detected in 34 patients (7%), and 23 of them were examined. The microthrombus disappeared in 13 patients and decreased in 7; PFO recanalization and anatomical variations were observed in 2 and 1 patient, respectively. The incidence of index stroke was higher in the microthrombus group than in the nonmicrothrombus group (76.47% versus 61.11%). Univariate and multivariable (adjusted) analyses revealed PFO as an independent risk factor for right atrial septal in situ microthrombus formation (odds ratio, 3.29 [95% CI, 1.49-7.26]; P=0.003).
Conclusions:
Transesophageal echocardiography effectively detects right atrial septal in situ microthrombus. A PFO may promote the formation of right atrial septal in situ microthrombus. Right atrial septal in situ microthrombus significantly increases the risk of PFO-associated stroke. This finding may be crucial in disease management strategies for patients with PFO.
Insights
A patent foramen ovale (PFO) may promote right atrial microthrombus formation, significantly increasing stroke risk. Transesophageal echocardiography can detect these microthrombi, aiding PFO-associated stroke management.
Area of Science:
- Cardiology
- Neurology
- Medical Imaging
Background:
- Patent foramen ovale (PFO)-associated stroke pathogenesis is complex, often linked to paradoxical embolism.
- The role of in situ thrombus formation within the right atrium remains under-investigated.
- Transesophageal echocardiography (TEE) is effective in detecting right atrial septal in situ microthrombi.
Purpose of the Study:
- To explore the relationship between right atrial septal in situ microthrombus and PFO-associated stroke.
- To investigate the pathophysiological basis of microthrombus formation in patients with PFO.
- To assess the diagnostic utility of TEE in identifying these microthrombi.
Main Methods:
- Prospective investigation of 466 patients with high clinical suspicion of PFO undergoing TEE.
- Detection and characterization of right atrial septal in situ microthrombi.
- Analysis of stroke incidence and risk factors, including PFO and microthrombus presence.
Main Results:
- Right atrial septal in situ microthrombus was detected in 7% of patients.
- The incidence of index stroke was higher in patients with microthrombi (76.47%) compared to those without (61.11%).
- PFO was identified as an independent risk factor for right atrial septal in situ microthrombus formation (OR, 3.29; P=0.003).
Conclusions:
- TEE is a valuable tool for detecting right atrial septal in situ microthrombi.
- PFO appears to promote the formation of these microthrombi.
- The presence of right atrial septal in situ microthrombi significantly elevates the risk of PFO-associated stroke, impacting management strategies.
