まとめ
ペースメーカーが心拍を感知できなくなるのは,特に右束の分岐ブロックで,中心室の脱極化が遅れているためです. これにより,正常に機能しているペースメーカーが誤火し,故障を模倣し,不必要なデバイスの交換につながる可能性があります.
科学分野:
- 心臓病学 心臓病学
- バイオメディカルエンジニアリング
背景:
- 通常機能するペースメーカーでは,センサーが故障することがあります.
- これらの障害は,しばしばペースメーカーの故障として誤診されます.
研究 の 目的:
- ペースメーカーの感知障害の以前に認識されていない原因を記述するために.
- この感知障害の根本的なメカニズムを特定するために.
主な方法:
- 非競争力のあるペースメーカーで感知障害を経験した30人の患者を研究した.
- 分析された心電図 (ECG) を用いて,心室脱極化タイミングと心室内伝導を評価した.
- QRS複合体の形態とタイミングがペースメーカーの感知行動と相関している.
主要な成果:
- 遅れた心室脱極化によって引き起こされる特定の感覚障害が特定されました.
- 右ブンドルブランクルブロック (RBBB) などの心室内伝導障害は,右心室頂部 (RVA) への偏移を遅らせます.
- ペースメーカーの電極は,次の予想されたインパルスから65ms以内に始まったQRS複合体を感知できず,不適切なペースメーカーの放電につながりました.
結論:
- 静脈内伝導の遅延は,ペースメーカーの非感受性の重要な原因です.
- この現象はペースメーカーの機能不全を模倣しますが,患者の内在の伝導システムによるものです.
- このことを認識することは,特に広範囲のQRS複合体を持つ患者の場合,早すぎるパルス発生器の置換を防ぐことができます.
関連する概念動画
Electrophysiology of Normal Cardiac Rhythm
The normal cardiac rhythm is a synchronized electrical activity that facilitates the regular and coordinated contraction of the heart muscle. This process is essential for efficient blood circulation throughout the body. The fundamental elements involved in establishing and maintaining this rhythm include the unique electrical properties of cardiac muscle cells, the sinoatrial (SA) node's pacemaker function, the specialized conducting system, and the ionic mechanisms underlying each phase of...
Mechanism 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.
Conduction System of the Heart
Autorhythmicity is a term that refers to the heart's inherent ability to generate electrical signals and instigate muscle contractions. This self-regulating conduction system within the heart consists of two key components: the pacemaker cells and specialized conducting cells.
The pacemaker cells are located in two primary nodes: the sinoatrial (SA) node and the atrioventricular (AV) node. The SA node pacemaker cells can autonomously depolarize, triggering an action potential that leads to the...
The pacemaker cells are located in two primary nodes: the sinoatrial (SA) node and the atrioventricular (AV) node. The SA node pacemaker cells can autonomously depolarize, triggering an action potential that leads to the...
Disturbances 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...
Dysrhythmias 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...
ECG 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...


