Related Experiment Video

Updated: Jun 7, 2026

Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
07:15

Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation

Published on: January 16, 2019

Pregnancy and short-coupled torsades de pointes

Katherine Burrows1, Judy Fox, Lee A Biblo

  • 1Division of Cardiology, Department of Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA.

Pacing and Clinical Electrophysiology : PACE
|November 3, 2010
PubMed

More Related Videos

Electrocardiogram Recordings in Anesthetized Mice using Lead II04:16

Electrocardiogram Recordings in Anesthetized Mice using Lead II

Published on: June 20, 2020

Related Concept Videos

Dysrhythmias II: Classification of Tachyarrhythmias01:28

Dysrhythmias II: Classification of Tachyarrhythmias

Tachyarrhythmias are a type of dysrhythmia where the heart rate exceeds 100 beats per minute. Here are some common types of tachyarrhythmias:Sinus TachycardiaSinus tachycardia originates from increased impulses from the sinus node, leading to an elevated heart rate. It is often triggered by stress, fever, or exercise.Patients may experience palpitations, a sensation of a racing heart, dizziness, and chest discomfort.Causes and Risk Factors: Common causes include physical exertion, emotional...
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias01:25

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...
Antiarrhythmic Drugs: Class III Agents as Potassium Channel Blockers01:12

Antiarrhythmic Drugs: Class III Agents as Potassium Channel Blockers

Class III antiarrhythmic drugs are a group of medications that can prolong action potentials in the heart. They achieve this by blocking potassium channels or enhancing inward currents from sodium channels. However, these drugs have a unique property of "reverse use-dependence," which is most pronounced at slower heart rates and can lead to torsades de pointes—a specific type of arrhythmia. However, it is essential to note that excessive QT interval prolongation—a measure of the heart's...
Antiarrhythmic Drugs: Class II Agents as β-Adrenergic Blockers01:24

Antiarrhythmic Drugs: Class II Agents as β-Adrenergic Blockers

Adrenergic stimulation generally impacts cardiac rate and rhythm. Specifically, stimulation of the β-adrenoceptors triggers an increase in intracellular calcium ion influx and pacemaker currents, which may cause arrhythmias. Catecholamines like adrenaline also demonstrate β2-adrenoceptor-mediated hypokalemia, impacting cardiac action potential and disrupting the normal cardiac rhythm. Class II antiarrhythmic drugs are β-adrenoceptor antagonists or β-blockers, which indirectly block calcium...
Dysrhythmias VII: Nursing Management of Dysrhythmias01:25

Dysrhythmias VII: Nursing Management of Dysrhythmias

Nursing management of dysrhythmias involves the following:AssessmentSubjective Assessment:The initial step involves gathering patient-reported symptoms such as dizziness, palpitations, and chest discomfort. It is crucial to collect a detailed history, including previous heart conditions, current medication use, and lifestyle factors like caffeine and alcohol consumption.Objective Assessment:This involves observing clinical signs such as jugular venous distention, cool and pale skin, and...
Cardiac Action Potential01:30

Cardiac Action Potential

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