Related Experiment Video

Updated: Jan 27, 2026

Use of a Percutaneous Ventricular Assist Device/Left Atrium to Femoral Artery Bypass System for Cardiogenic Shock
07:39

Use of a Percutaneous Ventricular Assist Device/Left Atrium to Femoral Artery Bypass System for Cardiogenic Shock

Published on: August 16, 2021

4.1K

Estimation of Central Venous Pressure by Pacemaker Lead Impedances in Left Ventricular Assist Device Patients

Teruhiko Imamura1, Joshua D Moss1, Erin Flatley1

  • 1From the Department of Medicine, University of Chicago Medical Center, Chicago, Illinois.

ASAIO Journal (American Society for Artificial Internal Organs : 1992)
|March 27, 2019
PubMed

Insights

Assessing volume status in left ventricular assist device (LVAD) patients is difficult. Researchers developed a new equation using cardiac resynchronization therapy (CRT) lead impedance to estimate central venous pressure (CVP) noninvasively.

Area of Science:

  • Cardiology
  • Biomedical Engineering
  • Medical Devices

Background:

  • Left ventricular assist device (LVAD) patients often have complex volume status assessment challenges.
  • Cardiac resynchronization therapy (CRT) devices are frequently implanted in LVAD patients.
  • CRT lead impedance may correlate with hemodynamic parameters.

Purpose of the Study:

  • To investigate the association between CRT lead impedance and central venous pressure (CVP) in LVAD patients.
  • To develop a noninvasive method for estimating volume status in LVAD patients.

Main Methods:

  • Prospective collection of 91 measurement sets from 11 LVAD patients with CRT devices during ramp tests.
  • Measurement of cardiac filling pressures and lead impedances (Right Atrial, Right Ventricular, Left Ventricular).
  • Derivation and validation of an equation to estimate CVP using lead impedance values.

Main Results:

  • All measured lead impedances (RA, RV, LV) showed significant association with CVP (p < 0.05).
  • A derived equation demonstrated significant correlation (r = 0.795) and good agreement with measured CVP.
  • The equation maintained strong association with measured CVP in a validation cohort (r = 0.705).

Conclusions:

  • A novel equation was derived to estimate CVP using CRT lead impedance measurements in LVAD patients.
  • This method offers a potential noninvasive tool for monitoring volume status in this patient population.

More Related Videos

Use of Two Intracorporeal Ventricular Assist Devices As a Total Artificial Heart08:49

Use of Two Intracorporeal Ventricular Assist Devices As a Total Artificial Heart

Published on: May 11, 2018

9.9K
In Vitro Thrombosis Test for Ventricular Assist Devices09:15

In Vitro Thrombosis Test for Ventricular Assist Devices

Published on: March 21, 2025

1.2K

Related Concept Videos

Definition and Measurement of Pressure: Atmospheric Pressure, Barometer, and Manometer02:57

Definition and Measurement of Pressure: Atmospheric Pressure, Barometer, and Manometer

Gas pressure is caused by force exerted by gas molecules colliding with the surfaces of objects. Although the force of each collision is very small, any surface of an appreciable area experiences a large number of collisions in a short time, which can result in high pressure.
42.8K
The Central Dogma01:25

The Central Dogma

Overview
139.3K
Impedance Combination01:21

Impedance Combination

Consider a string of christmas lights, each bulb symbolizing an impedance element. In this series configuration, the flow of electric current remains uniform across every component. This behavior aligns with Kirchhoff's Voltage Law (KVL), which asserts that the total impedance in such a setup equals the sum of individual impedances—akin to resistors in series. It follows that the voltage from the power source is distributed proportionally among these components, adhering to the voltage...
738
Impedances and Admittance01:23

Impedances and Admittance

In the realm of AC circuits, passive circuit elements like resistors, inductors, and capacitors take on a different character when characterized by phasor voltage and current. Their behavior is expressed through impedance, a vital concept in AC circuit analysis.
Impedance is a measure of resistance to sinusoidal current flow in an AC circuit. Unlike their behavior in DC circuits, where inductors appear as short circuits and capacitors as open circuits, the behavior of these components in AC...
1.9K
What are Estimates?01:06

What are Estimates?

It isn't easy to measure a parameter such as the mean height or the mean weight of a population. So, we draw samples from the population and calculate the mean height or mean weight of the individuals in the sample. This sample data acts as a representative measure of the population parameter. These sample statistics are known as estimates. 
The estimate for the mean of a sample is denoted by ͞x, whereas the mean of the population is designated as μ. Further, parameters such...
8.2K
Vapor Pressure02:34

Vapor Pressure

When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally collide with the surface of the condensed phase, and in some cases, these collisions will result in the molecules re-entering the condensed phase. The change from the gas phase to the liquid is called condensation. When the rate of condensation becomes equal to the rate of vaporization, neither the amount of the liquid nor the amount of the vapor...
40.2K