Keyword search (3,619 papers available)


Energy loss associated with in-vitro modeling of mitral annular calcification.

Author(s): Wiener PC, Darwish A, Friend E, Kadem L, Pressman GS

INTRODUCTION: Study aims were to compare hemodynamics and viscous energy dissipation (VED) in 3D printed mitral valves-one replicating a normal valve and the other a valve with severe mitral annular calcification (MAC). Patients with severe MAC develop tran...

Article GUID: 33591991
Proper Orthogonal Decomposition Analysis of the Flow Downstream of a Dysfunctional Bileaflet Mechanical Aortic Valve.

Author(s): Darwish A, Di Labbio G, Saleh W, Kadem L

PURPOSE: Aortic valve replacement remains the only viable solution for symptomatic patients with severe aortic valve stenosis. Despite their improved design and long history of successful operation, bileaflet mechanical heart valves are still associated wit...

Article GUID: 33469847
Impact of Mitral Regurgitation on the Flow in a Model of a Left Ventricle.

Author(s): Papolla C, Darwish A, Kadem L, Rieu R

PURPOSE: Mitral regurgitation (MR) is the second most common valve disease in industrialized countries. Despite its high prevalence, little is known about its impact on the flow dynamics in the left ventricle (LV). Because of the interdependence between val...

Article GUID: 33000444
Color Doppler Splay: A Clue to the Presence of Significant Mitral Regurgitation.

Author(s): Wiener PC, Friend EJ, Bhargav R, Radhakrishnan K, Kadem L, Pressman GS

J Am Soc Echocardiogr. 2020 Jul 22;: Authors: Wiener PC, Friend EJ, Bhargav R, Radhakrishnan K, Kadem L, Pressman GS

Article GUID: 32712051
Effects of Hemodynamic Conditions and Valve Sizing on Leaflet Bending Stress in Self-Expanding Transcatheter Aortic Valve: An In-vitro Study.

Author(s): Stanová V, Zenses AS, Thollon L, Kadem L, Barragan P, Rieu R, Pibarot P

Artif Organs. 2020 Jan 29;: Authors: Stanová V, Zenses AS, Thollon L, Kadem L, Barragan P, Rieu R, Pibarot P

Article GUID: 31995230
Experimental Investigation of the Effect of Heart Rate On Flow in the Left Ventricle in Health and Disease -- Aortic Valve Regurgitation.

Author(s): Di Labbio G, Ben-Assa E, Kadem L

J Biomech Eng. 2019 Nov 01;: Authors: Di Labbio G, Ben-Assa E, Kadem L

Article GUID: 31701119
Jet collisions and vortex reversal in the human left ventricle.

Author(s): Di Labbio G, Kadem L

J Biomech. 2018 09 10;78:155-160 Authors: Di Labbio G, Kadem L

Article GUID: 30049450
Response to letter to the editor: 'Left ventricular flow in the presence of aortic regurgitation'.

Author(s): Di Labbio G, Kadem L

J Biomech. 2019 Apr 18;87:212-214 Authors: Di Labbio G, Kadem L PMID: 30871721 [PubMed - in process]

Article GUID: 30871721
Experimental investigation of the flow downstream of a dysfunctional bileaflet mechanical aortic valve.

Author(s): Darwish A, Di Labbio G, Saleh W, Smadi O, Kadem L

Artif Organs. 2019 May 08;: Authors: Darwish A, Di Labbio G, Saleh W, Smadi O, Kadem L

Article GUID: 31066923
Title:Energy loss associated with in-vitro modeling of mitral annular calcification.
Authors:Wiener PC,  Darwish A,  Friend E,  Kadem L,  Pressman GS
Link:https://www.ncbi.nlm.nih.gov/pubmed/33591991
DOI:10.1371/journal.pone.0246701
Category:PLoS One
PMID:33591991
Dept Affiliation: ENCS
1 Division of Cardiology, Heart and Vascular Institute, Einstein Medical Center, Philadelphia, PA, United States of America.
2 Department of Mechanical, Industrial and Aerospace Engineering, Concordia University, Montreal, Canada.

Description:

Energy loss associated with in-vitro modeling of mitral annular calcification.

PLoS One. 2021; 16(2):e0246701

Authors: Wiener PC, Darwish A, Friend E, Kadem L, Pressman GS

Abstract

INTRODUCTION: Study aims were to compare hemodynamics and viscous energy dissipation (VED) in 3D printed mitral valves-one replicating a normal valve and the other a valve with severe mitral annular calcification (MAC). Patients with severe MAC develop transmitral gradients, without the commissural fusion typifying rheumatic mitral stenosis (MS), and may have symptoms similar to classical MS. A proposed mechanism relates to VED due to disturbed blood flow through the diseased valve into the ventricle.

METHODS: A silicone model of a normal mitral valve (MV) was created using a transesophageal echocardiography dataset. 3D printed calcium phantoms were incorporated into a second valve model to replicate severe MAC. The synthetic MVs were tested in a left heart duplicator under rest and exercise conditions. Fine particles were suspended in a water/glycerol blood analogue for particle image velocimetry calculation of VED.

RESULTS: Catheter mean transmitral gradients were slightly higher in the MAC valve compared to the normal MV, both at rest (3.2 vs. 1.3 mm Hg) and with exercise (5.9 vs. 5.0 mm Hg); Doppler gradients were 2.7 vs. 2.1 mm Hg at rest and 9.9 vs 8.2 mm Hg with exercise. VED was similar between the two valves at rest. During exercise, VED increased to a greater extent for the MAC valve (240%) versus the normal valve (127%).

CONCLUSION: MAC MS is associated with slightly increased transmitral gradients but markedly increased VED during exercise. These energy losses may contribute to the exercise intolerance and exertional dyspnea present in MAC patients.

PMID: 33591991 [PubMed - as supplied by publisher]