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

Pulse rhythm01:30

Pulse rhythm

Pulse rhythm refers to the pattern of pulsations within specific intervals, offering valuable insights into the regularity or irregularity of the heart's beats as observed through the pattern of pulsation within specific intervals. A regular pulse exhibits a consistent heart rate with uniform waveforms and pulsation force, variations of which can be classified as normal, weak, or bounding.
Conversely, an irregular pulse pattern is termed dysrhythmia, stemming from disruptions in cardiac muscle...
Electrocardiogram01:29

Electrocardiogram

An electrocardiogram (ECG or EKG) is a critical diagnostic tool that records the electrical signals produced by the heart during each heartbeat. This recording is achieved through electrodes placed strategically on the arms, legs, and chest. The electrocardiograph amplifies these signals and produces 12 distinct tracings, offering a comprehensive understanding of the heart's electrical activity.
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and the T...
Exercise Stress Test01:26

Exercise Stress Test

Introduction
Exercise stress testing, commonly known as a treadmill test, is a noninvasive procedure used to evaluate cardiovascular function and diagnose heart conditions.
Definition
An exercise stress test measures the heart's response to exertion using a treadmill or stationary bicycle. Chest electrodes record the heart's electrical activity through an ECG, and blood pressure is monitored regularly.
Purposes
Dysrhythmias V: Evaluating Dysrhythmias01:30

Dysrhythmias V: Evaluating Dysrhythmias

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...
Cardiomyopathy II: Dilated Cardiomyopathy01:30

Cardiomyopathy II: Dilated Cardiomyopathy

Dilated cardiomyopathy, or DCM, is a progressive myocardial disorder characterized by ventricular chamber dilation and contractile dysfunction.EtiologyVarious factors can cause DCM, including hypertension and heavy alcohol intake, which contribute to the weakening and enlargement of the heart muscle. Viral infections, such as Coxsackievirus B, adenoviruses, and influenza, can lead to DCM by causing inflammation and damage to heart tissue. Certain chemotherapeutic agents, including daunorubicin,...
Cardiomyopathy III: Hypertrophic Cardiomyopathy01:29

Cardiomyopathy III: Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy, or HCM, is an autosomal dominant genetic disorder characterized by asymmetric left ventricular hypertrophy without ventricular dilation. It is more common in men and is typically diagnosed in young, athletic adults.EtiologyHCM is primarily genetic and is caused by mutations in genes encoding sarcomeric proteins. Researchers have identified over 1400 mutations across at least 11 different genes. Among these, the most frequently occurring mutations are found in the...

You might also read

Related Articles

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

Sort by
Same author

Clinical application of demand pacemakers.

British medical journal·2010
Same author

Result of a british survey on artificial cardiac pacemakers.

British medical journal·2010
Same author

Predictors of angiographic findings when chest pain recurs after successful coronary angioplasty.

European heart journal·1995
Same author

'Tandem lesion' coronary angioplasty: ten years' experience.

Coronary artery disease·1995
Same author

Percutaneous transluminal coronary angioplasty in patients 70 years of age or older: 12 years' experience.

British heart journal·1995
Same author

Percutaneous transluminal coronary angioplasty of aorta ostial, non-aorta ostial, and branch ostial stenoses: acute and long-term outcome.

European heart journal·1995

Related Experiment Video

Updated: Jul 7, 2026

Programmed Electrical Stimulation in Mice
07:29

Programmed Electrical Stimulation in Mice

Published on: May 26, 2010

21.1K

Exercise testing in the indication and evaluation of pacemaker treatment.

E Sowton1

  • 1Department of Cardiology Guy's 'ospital, London, UK.

European Heart Journal
|August 1, 1987
PubMed
Summary

Rate-responsive pacing systems often fail to match heart rate with patient workload. P-wave and QT-driven pacing show inaccuracies, with limited benefits over fixed-rate pacing.

Area of Science:

  • Cardiology
  • Biomedical Engineering
  • Physiology

Background:

  • Pacemakers are crucial for managing bradycardia.
  • Rate-responsive pacing aims to optimize cardiac output during varying physiological demands.
  • Current systems face challenges in accurately reflecting patient workload.

Purpose of the Study:

  • To compare the efficacy of different rate-responsive pacing algorithms.
  • To evaluate the accuracy of heart rate response to workload across various pacing methods.
  • To assess the added benefit of atrioventricular (AV) synchrony in rate-responsive pacing.

Main Methods:

  • Comparison of multiple rate-responsive pacing systems in normal subjects.
  • Assessment of heart rate response against expected rates for a given workload.

More Related Videos

Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine
10:05

Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine

Published on: July 7, 2016

8.8K
Author Spotlight: Exercise Test for Evaluation of the Functional Efficacy of the Pig Cardiovascular System
02:47

Author Spotlight: Exercise Test for Evaluation of the Functional Efficacy of the Pig Cardiovascular System

Published on: May 12, 2023

1.9K

Related Experiment Videos

Last Updated: Jul 7, 2026

Programmed Electrical Stimulation in Mice
07:29

Programmed Electrical Stimulation in Mice

Published on: May 26, 2010

21.1K
Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine
10:05

Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine

Published on: July 7, 2016

8.8K
Author Spotlight: Exercise Test for Evaluation of the Functional Efficacy of the Pig Cardiovascular System
02:47

Author Spotlight: Exercise Test for Evaluation of the Functional Efficacy of the Pig Cardiovascular System

Published on: May 12, 2023

1.9K
  • Analysis of pacing data from P-wave driven and QT-driven modes.

    • Main Results:

    • Most rate-responsive pacing systems inaccurately matched heart rate to workload.
    • P-wave driven pacing often resulted in excessively high heart rates.
    • QT-driven pacing tended to produce heart rates that were too low for the workload.
    • Observed improvements over fixed-rate pacing were less significant than anticipated.
    • Additional benefits from AV synchrony were minimal beyond rate optimization.

    Conclusions:

    • Current rate-responsive pacing technologies require significant improvement for accurate workload matching.
    • P-wave and QT-based algorithms demonstrate limitations in physiological response.
    • The incremental value of AV synchrony in these systems appears limited.