eLVOTD: Estimation of the Left Ventricular Outflow Tract Diameter

OverviewThe left ventricular outflow tract diameter (LVOTD) is one of two measurements needed to calculate cardiac stroke volume and cardiac output (CO). CO is an important measure of heart function and can help determine the need for inotropic s…

Overview

The left ventricular outflow tract diameter (LVOTD)
is one of two measurements needed to calculate cardiac stroke volume and
cardiac output (CO). CO is an important measure of heart function and
can help determine the need for inotropic support of the heart. In
combination with mean arterial blood pressure, CO can also be used to
determine the systemic vascular resistance, which directs the use of
vasopressors. Currently, LVOTD (and therefore CO) is measured using an
indwelling pulmonary artery catheter. This technique requires a highly
advanced hospital setting to insert and maintain. As a result, the LVOTD
is determined for only about half of all patients that could benefit
from the measurement. This invention is a novel algorithm that estimates
LVOTD using ultrasound and several patient characteristics, which
simplifies and standardizes how CO is measured. The algorithm allows an
estimated LVOTD (eLVOTD) value to be obtained with any ultrasound
system, including console-based, laptop, tablet, handheld, continuous
patch/cutaneous monitors, and point of care ultrasounds (POCUS). eLVOTD
is related to another technology by the same inventor used to measure
stroke volume using ultrasound (SM-2016-067). Together, these tools
allow clinicians to make better decisions regarding inotropic
vasopressor use and volume management in critically ill patients. 

This technology is an algorithm that uses a patient’s age, sex,
height, weight, etc., as well as the left ventricular velocity time
integral (LV VTI) to calculate the estimated left ventricular outflow
tract diameter (eLVOTD). A retrospective review of 182 patients who had
undergone an echocardiogram to determine left ventricular outflow tract
demonstrated eLVOTD was a good estimate of LVOTD (RMSE = 0.15, R2
= 0.74). Use of eLVOTD will allow the echocardiographic calculation of
CO and stroke volume to be more easily performed by the physician.

Applications

POCUS is a $700 million dollar market with a
7-8% annual growth rate. The POCUS market is expanding as units are very
portable, relatively inexpensive, and the procedures can be performed
quickly. Despite this, there are no other significant applications
designed to assist physicians using POCUS to direct the care of
critically ill patients. As a result, the full potential of POCUS to
affect patient care has not been fully realized. This technology can be
incorporated into POCUS systems to significantly expand their
functionality and direct patient care.

Advantages

Can be used by or with any ultrasound system, including at the point-of-care

Increases the accuracy of echocardiographic calculation of cardiac output and stroke volume

Stage of Development

This technology is ready for further development and commercialization.

Website

https://www.umventures.org/technologies/elvotd-estimation-left-ventricular-outflow-tract-diameter

Contact Info

University of Maryland Baltimore

Office of Technology Transfer
620 W Lexington St., 4th Floor
Baltimore, MD 21201
Email: ott@umaryland.edu
Phone: (410) 706-2380

Website: www.umventures.org