Video Experimental Relacionado
Updated: Jul 16, 2026
08:56
Sterile Pericarditis in Aachener Minipigs As a Model for Atrial Myopathy and Atrial Fibrillation
Published on: September 24, 2021
La fibrilación auricular producida por el ritmo auricular rápido prolongado se asocia con cambios heterogéneos en la
J V Jayachandran1, H J Sih, W Winkle
1Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
Circulation
|March 15, 2000
Resumen
Las frecuencias cardíacas rápidas sostenidas durante la fibrilación auricular (FA) aumentan la actividad del nervio simpático en las aurículas. Esta inervación autónoma alterada se correlaciona con cambios en la actividad eléctrica auricular.
Área de la Ciencia:
- Cardiología Cardiología.
- Neurociencia Autónoma y Neurociencia Autónoma.
- Electrofisiología y electrofisiología.
Sus antecedentes:
- La fibrilación auricular (FA) implica cambios estructurales y electrofisiológicos debido a las tasas rápidas.
- El impacto de la FA sostenida en la inervación autonómica auricular sigue sin estar claro.
- Este estudio investiga la relación entre las velocidades auriculares rápidas y la inervación atrial autónoma.
Objetivo del estudio:
- Para determinar si los ritmos auriculares rápidos sostenidos alteran la inervación autónoma en las aurículas.
- Explorar la correlación entre la remodelación electrofisiológica y los cambios autónomos durante la AF.
Principales métodos:
- Seis perros se sometieron a aceleración auricular a 600 bpm para inducir una FA sostenida.
- La tomografía por emisión de positrones con [C-11] hidroxiefedrina (HED) se utilizó para evaluar la densidad terminal del nervio simpático.
- Se analizaron las concentraciones de norepinefrina y la electrofisiología auricular.
Principales resultados:
- Los perros acelerados mostraron una retención de HED y una concentración de norepinefrina significativamente mayores en los tejidos auriculares en comparación con los controles.
- La inervación simpática auricular fue heterogénea, con mayor retención de HED en la aurícula derecha.
- La duración del ciclo de fibrilación auricular fue más larga en la aurícula derecha y aumentó con el tratamiento con propranolol.
Conclusiones:
- Las tasas rápidas de FA conducen a un aumento heterogéneo de la inervación simpática auricular.
- Estos cambios autónomos están asociados con distintos efectos electrofisiológicos de la FA.
Videos de Conceptos Relacionados
01:28Mechanism of Cardiac Arrhythmias
Arrhythmias are irregular heart rhythms occurring when the heart's electrical impulses become abnormal. These disturbances can lead to various symptoms, depending on their severity and the underlying cause. Some common factors contributing to arrhythmias include hypoxia, ischemia, electrolyte imbalances, excessive catecholamine exposure, drug toxicity, and muscle overstretching. Arrhythmias can be classified into two main types based on the rate and site of origin of abnormal heart rhythms.
01:29Disturbances in Heart Rhythm
Arrhythmia or dysrhythmia refers to an abnormal heart rhythm caused by a defect in the heart's conduction system. It can cause the heart to beat irregularly, too quickly, or too slowly, leading to symptoms like chest pain, shortness of breath, and fainting. Factors such as stress, caffeine, alcohol, nicotine, cocaine, certain drugs, congenital defects, diseases, and electrolyte abnormalities can trigger arrhythmias.
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
01:28Dysrhythmias II: Classification of Tachyarrhythmias
Tachyarrhythmias are a type of dysrhythmia where the heart rate exceeds 100 beats per minute. Here are some common types of tachyarrhythmias:Sinus TachycardiaSinus tachycardia originates from increased impulses from the sinus node, leading to an elevated heart rate. It is often triggered by stress, fever, or exercise.Patients may experience palpitations, a sensation of a racing heart, dizziness, and chest discomfort.Causes and Risk Factors: Common causes include physical exertion, emotional...
01:29Dysrhythmias III: Characteristics of Dysrhythmias
Dysrhythmias, also known as arrhythmias, are irregular heart rhythms that result from abnormal electrical activity in the heart, affecting its ability to circulate blood efficiently. Tachyarrhythmias, a subset of dysrhythmias, are characterized by abnormally fast heart rates exceeding 100 beats per minute. Here are some types of tachyarrhythmias with their distinct ECG features:Sinus Tachycardia:Sinus tachycardia presents a regular heart rhythm with an increased rate of 101-180 beats per minute.
01:18Dysrhythmias IV: Characteristics of Bradyarrhythmias
Bradyarrhythmias are cardiac rhythm disorders characterized by a slower-than-normal heart rate, typically defined as fewer than 60 beats per minute. Some of which are discussed here:Sinus BradycardiaSinus bradycardia presents a heart rate lower than 60 beats per minute, with a regular rhythm originating from the SA node. The ECG typically shows normal P waves preceding each QRS complex, a normal PR interval (0.12 to 0.20 seconds), and a normal QRS duration (0.06 to 0.10 seconds).First-Degree AV...
01:25ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
Arrhythmia is a condition characterized by an irregular heart rhythm, with ECG changes that differ based on its origin and nature. The types of arrhythmias discussed below include atrial, junctional, and ventricular arrhythmias.Atrial ArrhythmiasPremature Atrial Complexes (PACs): PACs are early atrial beats caused by stress, caffeine, alcohol, electrolyte imbalances, hypoxia, hyperthyroidism, or certain medications (e.g., bronchodilators and decongestants). The ECG shows early P waves with an...