## Pulse v4.1.0 (March 2022)

- Software Architecture Improvements
  - Including build information
    - Added to all client facing API's (C++, Java, Python, C#) for external applications to get Pulse version
    - Added to state files to help identify compatibility with engine builds
  - New Hemodynamics Engine
    - Provides the ability to execute and optimize our cardiovascular circuit
    - Compares optimization iterations to validation data to converve on an optimal and valid circuit configuration
  - Updated to Eigen 3.4.0 and Protobuf 3.18.0
- Physiology Model Improvements
  - Added Lorazepam 
  - Added an oversedation drug as a test case
  - New Advanced Cardiac Life Support (ACLS) Arrhythimias with ECG waveforms
    - NormalSinus : Normal electrical signal and mechanical function
    - Sinus Bradycardia : Normal electrical signal with reduced heart rate
    - Sinus Tachycardia : Normal electrical signal and increased heart rate
    - Sinus Pulseless Electrical Activity : Organized electrical signal, but no mechanical function
    - Asystole : No electrical signal or mechanical function
    - Coarse Ventricular Fibrillation : Unorganized electrical signal, no mechanical function
    - Fine Ventricular Fibrillation : Unorganized electrical signal, reduced amplitude compared to coarse VF, no mechanical function
    - Pulseless Ventricular Tachycardia : Ventricular tachycardia electrical signal with reduced amplitude, but no mechanical function
    - Stable Ventricular Tachycardia : Ventricular tachycardia electrical signal with increased heart rate
    - Unstable Ventricular Tachycardia : Ventricular tachycardia electrical signal with increased heart rate, reduced heart elastance
  - ECG Waveforms use an interpolation algorithm to fit the waveform to the cardiac cycle
  - Ventilation equipment provides breath information to differentiate patient or equipment initiated breaths
  - Added configurable relief valve to mechanical ventilator
  - Added a suite of black box unit tests to verify data exchange combinations
  - Bug Fixes
    - Corrected flow calculations for compartments
    - Increased the frequency data is updated in the cardiovascular system during cardiac arrest
    - Replaced Irreversible states with more relavent clinical events: Pulse continues running, unlike during Irreversible states
    - Improved calculations of patient lung volumes due to disease