Making Physiology Happen


Pressure-Volume Loop Solutions


PVL Analysis Module

Zoom image


Pressure-volume (PV) loops have become the gold standard for studying myocardial contractility, compliance, muscle energetics and other quantitative measures of cardiac function. Typical applications for PV loops include heart failure studies, gene therapy and manipulation protocols and pharmacology studies.

Along with our partner, Transonic Scisense, Inc., iWorx offers a comprehensive acquisition and analysis solution for PV loop experiments. The foundation of these systems is the LabScribe Pressure-Volume Loop Module which allows for real-time display and analysis of elastance and compliance curves providing instant feedback on the quality of occlusions being performed. Unlike other software offerings for PV analysis, all the acquisition and analysis takes place within one program providing seamless and time saving options for generating data for publication.

The LabScribe PV Loop Module can be used to analyze pressure-volume data from any source including conductance catheters, admittance catheters, echo ultrasound systems or sonomicrometry dimension crystals.


Papers about measuring PV-Loops using iWorx systems on Google Scholar


Download brochure (.pdf)


IX-RA-834 Recorder
IX-RA-834 Multi-Channel Recorder
The iWorx RA Recorder is the most advanced and feature-rich physiological data acquisition system on the market. It comes standard with 8 general purpose input channels, a low voltage and high voltage stimulator, 8 digital outputs, a built-in barometric pressure sensor
and 4 iWire inputs.
IX-400 Series
IX-400 Series Recorders
Data Aquisition Systems are economical, high performance 6, 8 and 16 channel data recorders for use with a broad range of amplifiers. The recorders offer 16-bit resolution at maximum data collection speeds up to 10 KHz, making them appropriate for most research applications.



LabScribe Pressure Volume Loop Module

LS-PVL iWorx Pressure Volume Loop Software Module is a plug-in software module for iWorx data acquisition systems that performs pressure volume loop analysis for hemodynamic research in animals. The software module provides a powerful and easy to use tool for investigators to measure and analyze the hemodynamic parameters of cardiac and pulmonary pressure and volume data acquired by an iWorx recorder.
Cardiac cycle parameters that can be monitored online are:
  • Heart Rate,PVL Analysis Module
  • End Systolic Pressure,
  • End Diastolic Pressure,
  • Max Pressure,
  • Min Pressure,
  • Max dP/dt,
  • Min dP/dt,
  • Max Volume,
  • Min Volume,
  • End Systolic Volume,
  • End Diastolic Volume,
  • Stroke Volume,
  • Cardiac Output,
  • Ejection Fraction,
  • Stroke Work
Further analysis can be performed offline, such as selecting cycles, calculating Pressure-Volume Area, Potential Energy, Cardiac Efficiency, and plotting PV Loops, PRSW, Max dp vs EDV, PVA vs EDV, PVA vs ESP, can be performed. The data and graphs can be copied or exported to the built-in Journal or any external program.

The software module is plug and play compatible with all iWorx Data Acquisition and Analysis Modules.

Notable Features:

  • Real-time XY plotting
  • Real-time analysis of PV derived parameters
  • Real-time or offline calculation of admittance derived volume using raw signals from the Scisense ADVantage system
  • Calibration of classical conductance catheter volume using cuvette method or Baan’s equation
  • Volume calculations from sonomicrometry, echo ultrasound or pressure-volume systems
  • Calculation of stress-volume loops from VisualSonics echo ultrasound data
PV Loop Calculations:
  • Maximum and Minimum Volume
  • Diastolic and Systolic Volume
  • Stroke Volume
  • Cardiac Output
  • Ejection Fraction
  • End-Systolic Pressure Volume Relationship (ESPVR)
  • End-Diastolic Pressure Volume Relationship (EDPVR)
  • Preload-Recruitable Stroke Work (PRSW)
  • Pressure-Volume Area (PVA)
  • Arterial Elastance
  • Time-Varying Elastance
  • Maximum Power
  • Preload-Adjusted Maximal Power
  • Potential Energy
  • Cardiac Efficiency
  • Heart Rate Variability (HRV) Calculations
  • PV Loops
  • PRSW
  • Max dp/dt vs EDV
  • PVA vs EDV
  • PVA vs ESP
  • Time Varying Elastance
  • E(t) vs. time
  • Averaged PV loops
Detailed information about using the modules is in the LabScribe Manual

LS-20BP The LabScribe2 Blood Pressure Module acquires and analyzes data from blood pressure transducers. Data can be analyzed from ventricular and arterial signals in real-time. The software automatically calculates common indices of function from the blood pressure signal where it can easily be exported to another program for further analysis.


LS-30TXT  The iWorx ASCII Import Module enables import of data in text format that was recorded in any other data acquisition program. The module also allows the researcher to use the analysis functions in LabScribe software on data they may previously recorded with another a different program.