fabrication of percutaneous transvenous mitral annuloplasty testing device

Fabrication of Percutaneous

Transvenous Mitral Annuloplasty Testing

DeviceTeam 19

Kaitlyn ClarkeBrittany DePoi

Andrew ReynoldsAdarsha Selvachandran

Client: Dr. Wei Sun

Project Overview Dr. Sun has requested a testing

device that will allow his research team to obtain physical evidence regarding the response of cardiac tissue to implantation of the Percutaneous Mitral Annuloplasty System for the Treatment of Mitral Regurgitation

( aka. “stent bridge constriction device”)

Required project components:o Biological environment regulatoro Marker Tracking Systemo Force Determination Systemo Ultrasonic Detection

Distal Anchor

Nitinol Bridge

Proximal Anchor

Biological Environment Regulator

Purpose: support heart and simulate naturally occurring environmental conditions such as temperature, pressure, and blood flow

3 main components:o Water batho Camera mount and frameo Heart mount

Biological Environment Regulator Water Bath and Camera Mount

Water Batho Clear cast acrylic

sheetso Two separate baths

(inner and outer) Camera Mount

o Aluminumo Adjustable

Biological Environment Regulator Heart Mount

Secure enough to hold heart stable, loose enough to allow heart to move naturally in response to the stent bridge constriction device

Aluminum base Small hooks to securely hold

heart in place Rigid tube inserted into the

ascending aorta, down into the left ventricleo Structural supporto Pathway for saline that will

control pressure in the mitral valve

Base

Aorta Tube

Marker Tracking System Purpose: Understand mechanical changes experienced by heart

during stent deployment 15-20 small graphite markers on mitral annulus

plane 2 cameras 30-45 degrees apart to capture image Calibration Cube in field of view of each camera

Marker Tracking SystemAlgorithm

Direct linear transformation (DLT) MATLAB codeo Recreate image with reference to the three-dimensional

planeo Determine the 3-D position of each marker o Keep track of each marker and it’s movements from

frame to frameo Recognize if a marker leaves the frame of view of one of

both cameraso Calculate stress, strain, and deformation

Force Determination System Purpose: Determine relationship between force applied on the

mitral annulus by stent and the decrease in mitral valve prolapse

FlexiForce Sensorso Force measured at specific point as opposed to continuouso Use 6 sensors in an attempt to get more thorough data

Ultrasonic Detection Purpose: Capture Image of the coronary sinus before and after

stent deployment Ultrasound Machine has 2 probes one probe port Probe attached to machine will be changed between deployment

of stents

Distal Stent

Proximal Stent

Aortic Root

Mitral Valve (open)

Coronary Sinus

Mitral Valve (closed)

Coronary Sinus

Distance between coronary sinus and

valve

What’s Next?(We’ve ordered and received Plexiglas/FlexiForce)

Begin to build water bath Obtain computer from Kewei and begin

downloading Vision Software Build FlexiForce circuit and experiment with

sensors to determine the best way to adhere/use them

Test ultrasound to become comfortable with use and to determine the best settings to use