Chapters Archive – Page 21 of 22

Figure 2. Types of atrioventricular nodal reentry tachycardia (AVNRT).

Atrioventricular nodal reentry tachycardia (AVNRT): ECG features & management

Atrioventricular Nodal Reentry (Reentrant) Tachycardia (AVNRT): clinical features, mechanisms, ECG & management Atrioventricular nodal reentrant tachycardia (AVNRT) is a common tachyarrhythmia observed across all age…

Ectopic atrial rhythm (EAT), atrial tachycardia (AT) & multifocal atrial tachycardia (MAT)

Atrial rhythms: ectopic atrial rhythm, atrial tachycardia and multifocal atrial tachycardia Ectopic atrial tachycardia (EAT, or atrial tachycardia) arises when an ectopic focus within the…

Atrial flutter: classification, causes, ECG criteria and management

Atrial flutter Atrial flutter is the second most common pathological tachyarrhythmia. Only atrial fibrillation is more common. Atrial flutter occurs almost exclusively among persons with…

Figure 4. ECG showing Ashman's phenomenon during atrial fibrillation.

Atrial fibrillation: ECG, classification, causes, risk factors & management

Atrial fibrillation: definitions, causes, risk factors, ECG diagnosis and management Atrial fibrillation is the most common abnormal tachyarrhythmia (only sinus tachycardia is more common). The prevalence…

Figure 1. ECG showing sinus tachycardia. Paper speed 25 mm/s. Calculate the heart rate by dividing 300 by the number of large boxes between R-waves. There are approximately 3 large boxes between the R-waves; 300/3 equals 100 beats per minute.

Sinus tachycardia & Inappropriate sinus tachycardia

Sinus tachycardia: causes, ECG, normal variants & pathological variants Sinus tachycardia is the most common tachyarrhythmia (tachycardia). Sinus tachycardia is the result of an increased rate…

Sinus node dysfunction (SND) and sick sinus syndrome (SSS)

Sinus node dysfunction and sick sinus syndrome Sinus node dysfunction is an umbrella term for conditions that either affect the automaticity of the sinoatrial node…

Figure 1. Sinus bradycardia. Paper speed 25 mm/s. Calculate the rate by dividing 300 by the number of large boxes between two cycles (e.g between two R waves). As seen in the figure, there are approximately 6.5 large boxes between two R waves. 300/6.5 equals 46 beats/min.

Sinus bradycardia: definitions, ECG, causes and management

Sinus bradycardia: ECG, causes & management Definition of sinus bradycardia Sinus bradycardia fulfills the criteria for sinus rhythm but the heart rate is slower than…

Sinus arrhythmia (respiratory sinus arrhythmia)

Definition of sinus arrhythmia (respiratory sinus arrhythmia) Sinus arrhythmia and respiratory sinus arrhythmia both refer to the same phenomenon. Sinus arrhythmia fulfill all criteria for sinus…

Figure 1. Sinus rhythm. Paper speed 25 mm/s.

Sinus rhythm: physiology, ECG criteria & clinical implications

Sinus rhythm: the normal rhythm of the heart A rhythm is defined as three consecutive heartbeats with identical waveforms on the ECG. The similarity of…

$Figure 1. Aberrant conduction. The figure shows a supraventriclar extrasystole (an extra atrial impulse, discharged by an ectopic focus outside of the sinoatrial node). The supraventricular extrasystole arrives into the ventricles while the right bundle branch is still refractory, which is why it blocks the impulse. The resulting QRS-complex has a right bundle branch block pattern.$

Aberrant ventricular conduction (aberrancy, aberration)

Aberrant ventricular conduction (aberrancy, aberration) Aberrant conduction is not a mechanism of arrhythmia; it is a ventricular conduction disturbance. It is discussed in this chapter because…