Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

True Stress and True Strain01:28

True Stress and True Strain

852
Engineering stress is calculated as the load divided by the original, undeformed cross-sectional area. It approximates a material under load. This approximation is especially relevant post-yield in ductile materials. Though engineering stress-strain diagrams are often used for their convenience and accessibility, they can sometimes fall short in accuracy, particularly when dealing with large strain values.
In contrast, true stress offers a more precise portrayal. It is computed by dividing the...
852
Sustainable Development01:43

Sustainable Development

15.2K
As the human population continues to grow and use resources, we must be mindful of our planet’s natural limits. Sustainable development provides a pathway to maintain and improve human life now while also ensuring that future generations will have the resources that they need. The long-term success of sustainability efforts rests on understanding the interplay between human actions and ecological systems.
15.2K
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias01:25

ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias

601
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...
601
Design Example: Sustainability in Concrete Building01:26

Design Example: Sustainability in Concrete Building

424
As the construction industry moves towards more eco-friendly practices, concrete's adaptability and its ability to incorporate sustainable features make it a key material in the drive towards greener building solutions.
There are multiple approaches to achieve sustainability in a commercial concrete building. For instance, construct a concrete parking area under the building, utilizing pervious concrete paver blocks in open areas to facilitate rainwater collection through an underground...
424
Protein Complex Assembly02:41

Protein Complex Assembly

16.8K
Proteins can form homomeric complexes with another unit of the same protein or heteromeric complexes with different types.  Most protein complexes self-assemble spontaneously via ordered pathways, while some proteins need assembly factors that guide their proper assembly. Despite the crowded intracellular environment, proteins usually interact with their correct partners and form functional complexes.
Many viruses self-assemble into a fully functional unit using the infected host cell to...
16.8K
Protein Complexes with Interchangeable Parts01:57

Protein Complexes with Interchangeable Parts

2.9K
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order...
2.9K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Outbreak simulation on the neonatal ward using silica nanoparticles with encapsulated DNA: unmasking of key spread areas.

The Journal of hospital infection·2024
Same author

PRE-SURGICAL DIAGNOSTIC PARALLELS IN BASAL CELL CARCINOMA OF THE SKIN.

Georgian medical news·2022
Same author

CLINICAL SONOGRAPHIC ANALYSIS OF BIOMETRIC INDICATORS OF BUCCAL THICKNESS AND BUCCAL FAT PAD IN PATIENTS WITH DIFFERENT FACIAL TYPES.

Georgian medical news·2020
Same author

Cushing Syndrome Secondary to Primary Neuroendocrine Lung Carcinoma.

Case reports in endocrinology·2019
Same author

A review of the atrial upper rate algorithms of St. Jude Medical (Abbott) cardiac implantable electronic devices : Incidence of repetitive nonreentrant ventriculoatrial synchrony (RNRVAS).

Herzschrittmachertherapie & Elektrophysiologie·2017
Same author

Erratum to: Noise from a dysfunctional atrial lead detected as atrial fibrillation by a cardiac implantable electronic device.

Herzschrittmachertherapie & Elektrophysiologie·2017

Related Experiment Video

Updated: Feb 10, 2026

Patient-specific Modeling of the Heart: Estimation of Ventricular Fiber Orientations
12:09

Patient-specific Modeling of the Heart: Estimation of Ventricular Fiber Orientations

Published on: January 8, 2013

14.1K

True vs. pseudo-electrical ventricular alternans sustained by ventricular premature complexes.

S S Barold1, K Rajamani2, A Kucher3

  • 1Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. ssbarold@aol.com.

Herzschrittmachertherapie & Elektrophysiologie
|May 26, 2018
PubMed
Summary

This study identifies a rare form of electrical ventricular alternans caused by ventricular premature complexes (VPCs). This true alternans, unlike its pseudo-alternans counterpart, occurs with a constant heart rate and is often overlooked.

Keywords:
AlternansElectrical ventricular alternansPseudo-alternans

More Related Videos

In Vitro Thrombosis Test for Ventricular Assist Devices
09:15

In Vitro Thrombosis Test for Ventricular Assist Devices

Published on: March 21, 2025

1.2K
Induction of Right Ventricular Failure by Pulmonary Artery Constriction and Evaluation of Right Ventricular Function in Mice
09:40

Induction of Right Ventricular Failure by Pulmonary Artery Constriction and Evaluation of Right Ventricular Function in Mice

Published on: May 13, 2019

11.1K

Related Experiment Videos

Last Updated: Feb 10, 2026

Patient-specific Modeling of the Heart: Estimation of Ventricular Fiber Orientations
12:09

Patient-specific Modeling of the Heart: Estimation of Ventricular Fiber Orientations

Published on: January 8, 2013

14.1K
In Vitro Thrombosis Test for Ventricular Assist Devices
09:15

In Vitro Thrombosis Test for Ventricular Assist Devices

Published on: March 21, 2025

1.2K
Induction of Right Ventricular Failure by Pulmonary Artery Constriction and Evaluation of Right Ventricular Function in Mice
09:40

Induction of Right Ventricular Failure by Pulmonary Artery Constriction and Evaluation of Right Ventricular Function in Mice

Published on: May 13, 2019

11.1K

Area of Science:

  • Cardiology
  • Electrophysiology
  • Cardiac Arrhythmias

Background:

  • Ventricular alternans, a beat-to-beat variation in ventricular electrical activity, is typically associated with specific underlying conditions.
  • Ventricular premature complexes (VPCs) are common cardiac arrhythmias that can influence heart rhythm.
  • Distinguishing true alternans from its mimics is crucial for accurate diagnosis and management.

Observation:

  • A specific form of electrical ventricular alternans sustained by VPCs was observed.
  • This alternans presented with a constant heart rate (RR interval), consistent with true alternans.
  • In contrast, pseudo-alternans induced by VPCs typically exhibits an inconstant heart rate.

Findings:

  • True ventricular alternans can be sustained by VPCs, a phenomenon largely unreported.
  • The incidence of VPC-induced true alternans is likely underestimated due to measurement practices.
  • Late VPCs and their associated RR intervals are critical for identifying this condition.

Implications:

  • Recognizing VPC-induced true alternans can refine diagnostic criteria for cardiac arrhythmias.
  • This finding may necessitate re-evaluation of diagnostic protocols for ventricular alternans.
  • Understanding this mechanism could impact the management of patients with VPCs and alternans.