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

Dysrhythmias IV: Characteristics of Bradyarrhythmias01:18

Dysrhythmias IV: Characteristics of Bradyarrhythmias

501
Bradyarrhythmias are cardiac rhythm disorders characterized by a slower-than-normal heart rate, typically defined as fewer than 60 beats per minute. Some of which are discussed here:Sinus BradycardiaSinus bradycardia presents a heart rate lower than 60 beats per minute, with a regular rhythm originating from the SA node. The ECG typically shows normal P waves preceding each QRS complex, a normal PR interval (0.12 to 0.20 seconds), and a normal QRS duration (0.06 to 0.10 seconds).First-Degree AV...
501
Disturbances in Heart Rhythm01:29

Disturbances in Heart Rhythm

2.6K
Arrhythmia or dysrhythmia refers to an abnormal heart rhythm caused by a defect in the heart's conduction system. It can cause the heart to beat irregularly, too quickly, or too slowly, leading to symptoms like chest pain, shortness of breath, and fainting. Factors such as stress, caffeine, alcohol, nicotine, cocaine, certain drugs, congenital defects, diseases, and electrolyte abnormalities can trigger arrhythmias.
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
2.6K
Acute Coronary Syndrome III: Diagnostic Studies01:30

Acute Coronary Syndrome III: Diagnostic Studies

219
Diagnosing acute coronary syndrome or ACS begins with a thorough patient history. Notable symptoms include central, crushing chest pain radiating to the left arm, neck, jaw, or back, along with shortness of breath, sweating (diaphoresis), nausea, vomiting, dizziness, and palpitations.It is crucial to note any history of cardiac illnesses and assess risk factors, including age, gender, smoking, hypertension, diabetes, hyperlipidemia, and a sedentary lifestyle.During physical examination, vital...
219
Dysrhythmias V: Evaluating Dysrhythmias01:30

Dysrhythmias V: Evaluating Dysrhythmias

331
Dysrhythmias, also known as arrhythmias, are disturbances in the heart's rhythm that range from benign to life-threatening. A thorough evaluation is crucial for appropriate management and involves a comprehensive medical history, physical examination, and various diagnostic tests.Medical HistorySymptoms: Collect detailed information on palpitations, dizziness, syncope, chest pain, and fatigue. Note their onset, frequency, and triggers.Previous Cardiac Issues: Document any history of heart...
331
Dysrhythmias III: Characteristics of Dysrhythmias01:29

Dysrhythmias III: Characteristics of Dysrhythmias

425
Dysrhythmias, also known as arrhythmias, are irregular heart rhythms that result from abnormal electrical activity in the heart, affecting its ability to circulate blood efficiently. Tachyarrhythmias, a subset of dysrhythmias, are characterized by abnormally fast heart rates exceeding 100 beats per minute. Here are some types of tachyarrhythmias with their distinct ECG features:Sinus Tachycardia:Sinus tachycardia presents a regular heart rhythm with an increased rate of 101-180 beats per...
425
Mechanism of Cardiac Arrhythmias01:28

Mechanism of Cardiac Arrhythmias

1.7K
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.
1.7K

You might also read

Related Articles

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

Sort by
Same author

Physician Perspectives on the Initial Diagnostic Strategy of Syncope in Older Patients Without Diagnostic Clues.

Annals of noninvasive electrocardiology : the official journal of the International Society for Holter and Noninvasive Electrocardiology, Inc·2026
Same author

Tilt testing or implantable cardiac monitoring in the diagnosis of unexplained syncope.

Internal and emergency medicine·2025
Same author

The hope and the hype of artificial intelligence for syncope management.

European heart journal. Digital health·2025
Same author

Embryological incubation temperature modulates behaviour in larval white sturgeon (Acispencer transmontanus).

Journal of thermal biology·2025
Same author

Brief exposure to (-) THC affects zebrafish embryonic locomotion with effects that persist into the next generation.

Scientific reports·2025
Same author

Suppression of sleep syncope and vagally-mediated asystole by norepinephrine transporter inhibitor.

HeartRhythm case reports·2024

Related Experiment Video

Updated: Jan 18, 2026

Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System
10:17

Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System

Published on: April 11, 2025

1.6K

Clinical variables do not predict syncope in pacemaker patients with bifascicular block: a SPRITELY substudy.

Joshua Szaszkiewicz1, Robert Sheldon2, Satish Raj1

  • 1Libin Cardiovascular Institute, University of Calgary, 3280 Hospital Drive NW, Calgary, AB, T2 N 4Z6, Canada.

Clinical Autonomic Research : Official Journal of the Clinical Autonomic Research Society
|June 3, 2025
PubMed
Summary

In patients with bifascicular block and syncope, a history of asystole, supraventricular tachycardia, or diabetes predicts recurrence. This finding aids in managing syncope resistant to pacing.

Keywords:
Bifascicular blockClinical predictorsImplantable cardiac monitorPacemakerSyncope

More Related Videos

Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice
09:20

Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice

Published on: July 5, 2021

3.5K
Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice
08:05

Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice

Published on: June 29, 2022

3.4K

Related Experiment Videos

Last Updated: Jan 18, 2026

Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System
10:17

Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System

Published on: April 11, 2025

1.6K
Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice
09:20

Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice

Published on: July 5, 2021

3.5K
Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice
08:05

Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice

Published on: June 29, 2022

3.4K

Area of Science:

  • Cardiology
  • Electrophysiology
  • Clinical Trials

Background:

  • The SPRITELY study found no difference in syncope recurrence between pacemaker and implantable cardiac monitor groups in bifascicular block patients.
  • Predictors of syncope recurrence in patients with bifascicular block and permanent pacemakers remain unclear.

Purpose of the Study:

  • To identify baseline clinical characteristics that predict syncope recurrence in patients with bifascicular block and a permanent pacemaker.

Main Methods:

  • Retrospective analysis of the SPRITELY randomized clinical trial.
  • Evaluated 38 baseline clinical variables in 60 patients who received a pacemaker.
  • Used univariable and multivariate statistics to identify significant predictors (p < 0.05).

Main Results:

  • Recurrent syncope occurred in 12% of patients (20%).
  • Angiotensin receptor blockers (ARB) use and a history of asystole, supraventricular tachycardia (SVT), or diabetes were univariable predictors.
  • A history of asystole, SVT, or diabetes independently predicted syncope recurrence in multivariate analysis (p = 0.03).

Conclusions:

  • In older patients with syncope and bifascicular heart block, a history of asystole, SVT, or diabetes is a significant predictor of syncope recurrence.
  • These factors may help identify patients with syncope resistant to pacing.