Related Experiment Video
Updated: Aug 7, 2026
Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
Published on: July 20, 2022
Relation between sympathetic overactivity and left atrial spontaneous echo contrast in patients with mitral stenosis
Ozcan Ozdemir1, Omer Alyan, Mustafa Soylu
1Türkiye Yüksek Ihtisas Hospital, Cardiology Clinics, Ankara, Turkey. drozdemir75@yahoo.com
Insights
Sympathetic overactivity and reduced heart rate variability are linked to left atrial spontaneous echo contrast (LASEC) formation in mitral stenosis patients. This suggests increased sympathetic activity may drive platelet activation, contributing to LASEC development.
Area of Science:
- Cardiology
- Autonomic Nervous System Research
- Thrombosis and Hemostasis
Background:
- Spontaneous echo contrast (SEC) in the left atrium (LA) of mitral stenosis (MS) patients correlates with increased thromboembolism risk.
- Platelet activation has been observed in patients with SEC, suggesting a role in its pathogenesis.
- Autonomic nervous system (ANS) activity's influence on SEC formation in rheumatic MS with sinus rhythm requires further investigation.
Purpose of the Study:
- To investigate the impact of autonomic nervous system activity on left atrial spontaneous echo contrast (LASEC) formation in patients with rheumatic mitral stenosis (MS) and sinus rhythm.
- To analyze heart rate variability (HRV) parameters in relation to LASEC presence and platelet activation markers.
Main Methods:
- Heart rate variability (HRV) analysis was performed on 26 patients with LASEC and 28 control patients without LASEC.
- Key HRV parameters including standard deviation of NN intervals (SDNN), root mean square of successive differences (RMSSD), and high frequency (HF) components were assessed.
- Statistical analysis compared HRV metrics and identified predictors of LASEC formation and sP-selectin levels.
Main Results:
- Patients with LASEC exhibited higher mean heart rate, low frequency (LF), and LF/HF ratio, alongside lower SDNN, RMSSD, PNN50, and HF values compared to controls.
- Specific thresholds for SDNN (<90ms), LF (>79.5), and LF/HF ratio (>3.7) demonstrated high sensitivity and specificity in distinguishing patients with LASEC.
- Left atrial diameter, heart rate, SDNN, LF/HF ratio, and sP-selectin levels were significant predictors of LASEC formation.
Conclusions:
- Overactivity of the sympathetic nervous system and diminished heart rate variability are key factors in the development of LASEC and elevated s-P selectin levels.
- Platelet activation, potentially mediated by heightened sympathetic activity, appears to play a crucial role in the pathogenesis of LASEC.
- These findings highlight the interplay between autonomic dysfunction, platelet activation, and thromboembolic risk in mitral stenosis patients.
Background:
Spontaneous echo contrast (SEC) is common in patients with mitral stenosis (MS) and presence of SEC in left atrium (LA) is associated with a higher risk of thromboembolism. Recently, an increase in activation of platelets was demonstrated in patients with SEC raising the hypothesis that platelets are involved in the pathogenesis of SEC. In this study, we evaluated effects of autonomic nervous system activity on SEC formation in patients with rheumatic MS and sinus rhythm by heart rate variability analysis.
Methods And Results:
Twenty-six patients with LASEC were compared with 28 patients without LASEC. Mean heart rate, low frequency (LF) and low frequency/high frequency (LF/HF) ratio were significantly higher, standard deviation of all NN (SDNN), root mean square of successive differences (RMSSD), number of NN intervals that differed by more than 50 ms from adjacent interval divided by the total number of all NN intervals (PNN50) and high frequency (HF) values were lower in the patients with LASEC. A standard deviation of all NN intervals <90ms separated the patients with LASEC from control subjects with a sensitivity of 77% and specificity of 90%; a low frequency >79.5 with a sensitivity of 92% and specificity of 90; a low frequency/high frequency ratio >3.7 with a sensitivity of 96% and specificity of 90%. A left atrial diameter >4.3 cm increased the LASEC formation by 3.0 folds, HR >78 beats/min by 6.4 folds, standard deviation of all NN intervals <90 ms by 9.2 folds, a low frequency/high frequency ratio >3.7 by 6.4 folds, sP-selectin>142 by 5.8 folds. Variables affecting sP-selectin levels were LA diameter, mitral valve area, transmitral mean gradient, left ventricular ejection fraction, the presence of mitral regurgitation, HR, standard deviation of all NN intervals, low frequency, high frequency and low frequency/high frequency ratio.
Conclusion:
Sympathetic overactivity and reduced heart rate variability are important determinants for LASEC formation and increased s-P selectin levels. Therefore, platelet activation via increased sympathetic activity may play an important role in pathogenesis of LASEC.
Related Concept Videos
01:23Mitral Stenosis II: Clinical features and Diagnostic Tests
01:22Mitral Stenosis I: Introduction
01:23Mitral Regurgitation II: Clinical Features and Diagnostic Tests
01:20Mitral Regurgitation I: Introduction
01:22Aortic Regurgitation II: Clinical Features and Diagnostic Tests
01:20Imaging Studies for Cardiovascular System II:Types of Echocardiography
Types of Echocardiography
Transthoracic Echocardiography (TTE)
TTE is the most common type of echocardiogram which involves placing a transducer on the patient's chest, emitting sound waves to create heart images. TTE is invaluable for evaluating the heart's size, structure, and motion, making it particularly useful for diagnosing...