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

Blood Flow01:29

Blood Flow

Blood is pumped by the heart into the aorta, the largest artery in the body, and then into increasingly smaller arteries, arterioles, and capillaries. The velocity of blood flow decreases with increased cross-sectional blood vessel area. As blood returns to the heart through venules and veins, its velocity increases. The movement of blood is encouraged by smooth muscle in the vessel walls, the movement of skeletal muscle surrounding the vessels, and one-way valves that prevent backflow.
Accelerating Fluids01:17

Accelerating Fluids

When a fluid is in constant acceleration, the pressure and buoyant force equations are modified. Suppose a beaker is placed in an elevator accelerating upward with a constant acceleration, a. In the beaker, assume there is a thin cylinder of height h with an infinitesimal cross-sectional area, ΔS.
The motion of the liquid within this infinitesimal cylinder is considered to obtain the pressure difference. Three vertical forces act on this liquid:
Cardiac Output and Stroke Volume01:11

Cardiac Output and Stroke Volume

Cardiac output (CO) is an integral aspect of human physiology, reflecting the heart's efficiency and responsiveness to the body's needs. It represents the volume of blood that the left or right ventricle ejects into the aorta or pulmonary trunk each minute. The CO is calculated by multiplying the heart rate (HR)—the number of heartbeats per minute—by the stroke volume (SV)—the amount of blood pumped out with each heartbeat.
In an average resting adult male, the typical cardiac output averages...
Development of Blood Vessels01:07

Development of Blood Vessels

The development of the vascular system in a fetus is a complex and intricate process that begins as early as 15 to 16 days post-conception. This process starts outside the embryo, specifically in the mesoderm of the yolk sac, chorion, and connecting stalk. Approximately two days later, the formation of blood vessels occurs within the embryo itself.
The initial formation of this system is facilitated by the small amount of yolk present in the ovum and yolk sac. Blood vessels originate from...
Cardiac Output II: Effect of Stroke Volume on Cardiac Output01:22

Cardiac Output II: Effect of Stroke Volume on Cardiac Output

Cardiac output (CO), the amount of blood the heart pumps per minute, is a parameter in cardiovascular physiology determined by stroke volume and heart rate. Stroke volume, the amount of blood pushed from one of the ventricles per heartbeat, is influenced by preload, afterload, and contractility.
Preload
Preload refers to the initial elongation of the cardiac myocytes before contraction and is related to the volume of blood filling the heart at the end of diastole, or end-diastolic volume. The...
Turbulent Flow01:24

Turbulent Flow

Turbulent flow is characterized by unpredictable fluctuations in velocity and pressure, which result in a chaotic fluid movement distinct from the orderly patterns of laminar flow. While laminar flow is governed by smooth, parallel layers with minimal mixing, turbulent flow exhibits highly irregular, three-dimensional patterns. This behavior arises due to instabilities in the fluid's velocity profile, and amplifies as the flow velocity increases. Minor disturbances, known as turbulent spots,...

You might also read

Related Articles

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

Sort by
Same author

Procedural Strategies for Optimal Transcatheter Aortic Valve Replacement: An International Position Statement.

JACC. Cardiovascular interventions·2026
Same author

Percutaneous "Double-Seal" Strategy With Occluder Plus TAV-in-TAV for Post-TAVR Aortic Root-to-Right Ventricle Fistula.

JACC. Cardiovascular interventions·2026
Same author

Cardiac remodelling and clinical outcomes after mitral edge-to-edge repair with the PASCAL® system.

European heart journal. Imaging methods and practice·2026
Same author

Eyeballing versus comprehensive geriatric frailty assessment and outcomes after transcatheter aortic valve replacement: Insights from a large cohort.

Cardiovascular revascularization medicine : including molecular interventions·2026
Same author

Balloon-Expandable Versus Self-Expanding Valves in Patients With Small Aortic Annuli Undergoing Transcatheter Aortic Valve Replacement.

The American journal of cardiology·2026
Same author

Redo-TAVR (TAV-in-TAV) Best Practices Part 1: Short-in-Short and Short-in-Tall - A Heart and Valve Collaboratory Document.

JACC. Cardiovascular interventions·2026

Related Experiment Video

Updated: Jun 19, 2026

Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
11:00

Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section

Published on: July 19, 2016

11.6K

Inflow-to-Outflow Stent Frame Expansion, Ellipticity, and Decoupling in Evolut TAVR: Implications for Mid-term

Rishi Puri1, Julianne Spencer2, Didier Tchétché3

  • 1Heart, Vascular & Thoracic Institute, Cleveland Clinic, Ohio.

Journal of the Society for Cardiovascular Angiography & Interventions
|March 10, 2025
PubMed
Summary

Transcatheter aortic valve replacement (TAVR) frame ellipticity and expansion were assessed. Inflow underexpansion did not impact 4-year hemodynamics, but leaflet region underexpansion was linked to a smaller effective orifice area.

Keywords:
hemodynamicshypoattenuating leaflet thickeningnonuniform expansionstent frame decouplingtranscatheter aortic valve replacement

More Related Videos

Noninvasive Determination of Vortex Formation Time Using Transesophageal Echocardiography During Cardiac Surgery
04:48

Noninvasive Determination of Vortex Formation Time Using Transesophageal Echocardiography During Cardiac Surgery

Published on: November 28, 2018

7.9K
Particle Image Velocimetry Investigation of Hemodynamics via Aortic Phantom
06:26

Particle Image Velocimetry Investigation of Hemodynamics via Aortic Phantom

Published on: February 25, 2022

3.4K

Related Experiment Videos

Last Updated: Jun 19, 2026

Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
11:00

Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section

Published on: July 19, 2016

11.6K
Noninvasive Determination of Vortex Formation Time Using Transesophageal Echocardiography During Cardiac Surgery
04:48

Noninvasive Determination of Vortex Formation Time Using Transesophageal Echocardiography During Cardiac Surgery

Published on: November 28, 2018

7.9K
Particle Image Velocimetry Investigation of Hemodynamics via Aortic Phantom
06:26

Particle Image Velocimetry Investigation of Hemodynamics via Aortic Phantom

Published on: February 25, 2022

3.4K

Area of Science:

  • Cardiovascular Imaging
  • Interventional Cardiology
  • Biomedical Engineering

Background:

  • Native aortic annulus exhibits variable ellipticity, influencing transcatheter aortic valve (TAV) performance.
  • Noncircular and underexpanded TAVs may compromise hemodynamic outcomes.
  • This study investigates Evolut TAV frame geometry and its clinical impact.

Purpose of the Study:

  • Quantify Evolut TAV frame ellipticity and expansion 30 days post-transcatheter aortic valve replacement (TAVR).
  • Evaluate the impact of frame deformation on hypoattenuating leaflet thickening at 1 year and hemodynamics at 4 years.

Main Methods:

  • Retrospective analysis of 184 patients from the Evolut Low Risk substudy.
  • Computed tomography imaging used to quantify frame ellipticity ratio and percent expansion.
  • Association analysis of frame deformation with clinical outcomes.

Main Results:

  • Evolut frame ellipticity was highest at the inflow and lowest at the leaflet and outflow regions.
  • Frame expansion was lowest at the inflow and highest at the leaflet region.
  • Inflow frame deformation did not affect 4-year hemodynamics; leaflet region underexpansion correlated with reduced effective orifice area.

Conclusions:

  • Evolut frame deformation at the inflow does not compromise leaflet region geometry or expansion.
  • Mid-term hemodynamic performance (4 years) is not adversely affected by inflow frame geometry.
  • Leaflet region underexpansion is a critical factor for long-term TAV function.