New LabChart 7.1 Module: PV Loop

The PV Loop Module for LabChart allows you to record and analyze left ventricular pressure and volume data for hemodynamic research in animals. Analyses can be conducted during sampling or on pre-recorded data. You can display the pressure-volume loops, decide which loops to include and exclude from your analyses, and compute end-systolic and end-diastolic pressure volume relationships. A wide range of hemodynamic parameters can be calculated including pressure volume area, stroke work, and cardiac output. 

The module allows you to convert data to absolute volumes using cuvette calibration and to correct for parallel conductance using saline calibration - all in one data file. 

PV Loop with split pane Chart View (top left), Hemodynamics Table (bottom left), Loop View (top right),
PRSW plot (bottom right).

Analysis Manager

The Analysis Manager has been specially developed for PV Loop, and provides a way to save the settings of an analysis. This allows separate data regions within a data file to be analyzed, the results of the analysis to be saved and each saved analysis set to be recalled. 

The Analysis Manager dialog box

Loop view

In Loop View, individual loops can be examined, and selected or excluded from analyses. The end-systolic and end-diastolic PV relationships (ESPVR and EDPVR) are automatically calculated and displayed. You can choose which ESPVR and EDPVR regression fit to display in Loop View (linear, quadratic, or exponential).

 
Loop View

Hemodynamics Table

A wide range of hemodynamic parameters are calculated and displayed on a loop-by-loop basis. You can choose which hemodynamic parameters are included in the table, e.g. pressure volume area, stroke work, and cardiac output.

Hemodynamics Table (top) and display options dialog (below).

 Plots and linear regression information can be displayed for:

• dP/dt max vs. EDV
• PVA vs. ESP
• PVA vs. EDV
• Preload-Recruitable Stroke Work (PRSW) 

dP/dT Max vs. EDV Plot (top left) ; PVA vs. ESP Plot (top right);
PVA vs. EDV Plot (bottom left) and PRSW Plot (bottom right).

Calibration of volume data

There are two calibration methods available in the PV Loop module. 

• Cuvette calibration can be computed and applied to the volume channel. Settings files with known volumes of common cuvettes are supplied. 
• Saline calibration allows the parallel volume correction factor to be calculated and applied to the volume channel.

A PV Loop Help File and Getting Started tutorial are available in the LabChart 7.1 Welcome Center.

Cuvette Calibration (top) and Saline Calibration (bottom)

LabChart Pro users can download PV Loop for free. Upgrade to LabChart Pro to receive all LabChart software, LabChart modules and five years of free software upgrades.

20 May 2010