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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
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]