Related Experiment Video
Updated: Jun 13, 2025

06:14
Translational Rabbit Model of Chronic Cardiac Pacing
Published on: January 6, 2023
2.5K
Transient pacing pulse on the T-wave: What is the mechanism?
1Department of Cardiology, Soka Municipal Hospital, Saitama, Japan.
Indian Pacing and Electrophysiology Journal
|September 13, 2024
Abstract:
A patient with a dual-chamber pacemaker for sick sinus syndrome was hospitalized for heart failure. The electrocardiography (ECG) during hospitalization displayed seemingly abnormal pacing artifacts. This report focuses on the problem-solving of an abnormal-looking paced ECG and identifies the pacemaker's operational behavior as the underlying reason.
Related Concept Videos
Electrophysiology of Normal Cardiac Rhythm
2.3K
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...
2.3K
Cardiac Action Potential
1.1K
Cardiac action potentials are essential for proper heart function, enabling the rhythmic contractions needed for adequate blood circulation. Nodal cells and Purkinje fibers, specialized for electrical conduction, generate these action potentials.
The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials
The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials
1.1K
Correlation between ECG and Cardiac Cycle
3.6K
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...
3.6K
The Cardiac Cycle
86.9K
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...
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...
86.9K
Pulse rhythm
771
Pulse rhythm refers to the pattern of pulsations within specific intervals, offering valuable insights into the regularity or irregularity of the heart's beats as observed through the pattern of pulsation within specific intervals. A regular pulse exhibits a consistent heart rate with uniform waveforms and pulsation force, variations of which can be classified as normal, weak, or bounding.
Conversely, an irregular pulse pattern is termed dysrhythmia, stemming from disruptions in cardiac...
Conversely, an irregular pulse pattern is termed dysrhythmia, stemming from disruptions in cardiac...
771
Mechanism of Cardiac Arrhythmias
900
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.
900

