胎児の上心室動脈拍動脈の開始と終了時の磁気動脈拍数パターン
R T Wakai1, J F Strasburger, Z Li
1Department of Medical Physics, University of Wisconsin-Madison, USA. rtwakai@wisc.edu
Circulation
|January 23, 2003
まとめ
胎児マグネトカルディオグラフィは,前述の仮定に異議を唱えて,上心室高動脈症 (SVT) の開始と終了のさまざまなパターンを明らかにした. 再発性早発性心房収縮 (PAC) は最も一般的な開始パターンであり,胎児の動きがSVTに影響を与えた.
科学分野:
- 心臓病学 心臓病学
- 胎児医学 胎児医学について
- 電気生理学 電気生理学
背景:
- 超心室性短心症 (SVT) は,胎児の生命を脅かす最も一般的な胎児不律症です.
- 胎児性SVTの開始と終了のメカニズムを理解することは,管理に不可欠です.
- 胎児磁気心臓撮影 (fMCG) は,胎児の心臓電気生理学を研究するための非侵襲的な方法を提供します.
研究 の 目的:
- fMCGを使用して,再侵入胎児のSVTの開始と終了の電気生理学的パターンを特徴付ける.
- 観測されたパターンを,SVTメカニズムに関する既存の期待と比較する.
- SVTにおける胎児の動きと自律的影響の役割を調査する.
主な方法:
- 電気生理学的信号を記録するために胎児磁気心臓撮影 (fMCG) を利用しました.
- QRSと心室間隔を含む波形形態とタイミングを分析した.
- 胎児の動きを評価するためにfMCGアクトカルジオグラフィとfMCGfMCGデータを相関させた.
主要な成果:
- 予想とは異なる胎児SVTの5つの異なる開始パターンと4つの終結パターンを特定しました.
- リエントラント早発性心房収縮 (PAC) は,最も頻繁な開始パターンでした.
- 胎児の幹の動きとSVTの開始/終了との間に有意な関連性が観察され,自律的影響を示唆しています.
結論:
- 胎児のSVT開始と終了のパターンは,これまで理解されていたよりも多様です.
- 再突入型PACは胎児のSVTを誘発する主要なメカニズムである.
- fMCGは,胎児タキアリズム症の非侵襲的分析に有効であり,メカニズムを理解し,治療を導くのに役立ちます.
関連する概念動画
01:13The Cardiac Cycle
The heart beats rhythmically in a sequence called the cardiac cycle—a rapid coordination of contraction (systole) and relaxation (diastole).
The Process
Electrical signals—sent from the sinoatrial (SA) node in the right atrial wall to the atrioventricular (AV) node between the right atrium and right ventricle—cause both atria to simultaneously contract. When the signal reaches the AV node, it pauses for approximately a tenth of a second, allowing the atria to contract and empty blood into the...
The Process
Electrical signals—sent from the sinoatrial (SA) node in the right atrial wall to the atrioventricular (AV) node between the right atrium and right ventricle—cause both atria to simultaneously contract. When the signal reaches the AV node, it pauses for approximately a tenth of a second, allowing the atria to contract and empty blood into the...
01:19Electrophysiology 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...
01:19Conduction 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...
01:29Cardiac Cycle
The cardiac cycle refers to the sequence of events that occur in the heart from the beginning of one heartbeat to the next. It's characterized by alternating periods of contraction (systole) and relaxation (diastole) of the heart muscles.
During the cardiac cycle, blood flow through the heart is regulated entirely by changing pressure gradients. This sequence of events begins with the heart in a state of total relaxation, known as mid-to-late diastole, during which blood passively flows from...
During the cardiac cycle, blood flow through the heart is regulated entirely by changing pressure gradients. This sequence of events begins with the heart in a state of total relaxation, known as mid-to-late diastole, during which blood passively flows from...
01:25Correlation between ECG and Cardiac Cycle
The electrical signals recorded on an electrocardiogram (ECG) occur before the mechanical processes of contraction and relaxation during the cardiac cycle.
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
01:14Fetal Circulation
Fetal circulation is a unique system that facilitates the exchange of gases, nutrients, and waste products between the developing fetus and the mother. This intricate process takes place through a special organ called the placenta.
Two umbilical arteries transport blood from the fetus to the placenta. At the placenta, the blood absorbs oxygen and nutrients while simultaneously eliminating waste products. This oxygen-enriched and nutrient-rich blood then returns to the fetus through one...
Two umbilical arteries transport blood from the fetus to the placenta. At the placenta, the blood absorbs oxygen and nutrients while simultaneously eliminating waste products. This oxygen-enriched and nutrient-rich blood then returns to the fetus through one...