Atrial premature beats with cycle-dependent J waves/ST-segment elevation
1Department of Electrocardiogram Room, Jining No.1 People's Hospital, Jining, Shandong, China.
Abstract:
The cases reported in this study have the following characteristics: ① no J waves were observed in sinus beats, while transient J waves (Cases 1 and 3) or J point/ST-segment elevation (Case 2) appeared in atrial premature beats (APB), indicating that the occurrence of significant J waves/ST-segment elevation was dependent on short cycles (Cases 1 and 2) or long-short-cycle sequences (Case 3); ② the degree of J waves/ST-segment elevation was significant in all cases. Analysis suggests that short-cycle-dependent or long-short-cycle sequence-dependent J waves/ST-segment elevation is an ECG manifestation that can be caused by different underlying mechanisms, namely repolarization abnormalities and/or depolarization abnormalities.
Related Concept Videos
Dysrhythmias III: Characteristics of Dysrhythmias
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
Dysrhythmias IV: Characteristics of Bradyarrhythmias
Correlation between ECG and 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...
Electrocardiogram Fundamentals
An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
Definition
An electrocardiogram (ECG) visualizes the heart's electrical activity by tracing the electrical movement associated with each heartbeat on a graph or monitor. As the heart beats, an electrical wave passes through it, correlating with the cardiac cycle events.
Parts of an ECG
An ECG utilizes electrodes on the skin to...
Electrocardiogram
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and the T...


