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About the App

This first-of-it's-kind iPad application is an interactive simulation-based digital textbook of cardiovascular physiology and hemodynamics. A full range of topics relevant to the understanding of hemodynamics in health and disease are covered.

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The full text is divided into four parts:

  • Part I: Basic Physiological Concepts
  • Part II: Advanced Physiological Concepts
  • Part III:Pathophysiology, Disease States and Therapeutics
  • Part IV: Mechanical Circulatory Support

Part I is complete and included in its entirety in the current application. Additional chapters from Parts II, III and IV will be made available as they are completed. A preliminary list of subjects to be included in each of these Parts can be viewed by tapping the respective textbook cover on the app's Main Menu or can be found on the homepage. A fifth part covering Congenital Heart Diseases is also envisioned.

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Our Philosophy and Approach

The cardiovascular system is dynamic, with properties that change on a moment-by-moment basis. Significant understanding of how the different parts of the system work together to determine overall cardiovascular performance can be obtained in an interactive environment where parameters can be changed and the effects on output variables can be observed.

Our philosophy is that the most effective way to learn these concepts is by doing. Our approach has therefore been to create an interactive environment for doing, through the implementation of a computer-based simulation of the cardiovascular system.

Learn By Doing

In the past, medical and graduate schools required students to participate in live animal laboratories in order to obtain the hands-on experience necessary to gain appreciation for many of the concepts discussed in this textbook. With the availability of sophisticated cardiovascular models, much of this can be obtained from interactive computer simulations. Four different learn-by-doing features are incorporated throughout this textbook.

interactive simulation

Interactive Questions

At the end of each Chapter, the reader will have the option to enter a Questions section that contains problem sets and self assessment questions. In many cases, the answers require the user to design and execute an experiment using the simulation and to collect and interpret the data.

key points

Key Points

At the begining of each chapter is a "Key Points" button. When tapped, a popup window appears and lists the major take home messages of the chapter.

try it now

Try it Now

Embedded within text that describes a principle or the effects of a parameter that characterizes a cardiovascular property, the reader will be offered a "Try it Now" button. When tapped, a pop-up window appears that allows the reader to modify the parameter of interest and observe, in real time, its impact on indices of cardiovascular performance.


Access to the complete cardiovascular simulation underlyinig this textbook is available by selecting the "Full Simulation" button present at the top of the screen. In this mode, all cardiovascular parameters can be modified and all output variables can be viewed. An infinite number of combinations of parameter values can be explored to simulate different clinical settings and therapies.

Make a Suggestion

This textbook is meant to be a living application; to be updated over time with new chapters, new questions and new and improved text. Updates and new features will be added and disseminated seamlessly through the App Store. This feature will be utilized to keep readers fully updated with the latest versions of PV Loops and to offer new features as they become available.

In addition, users are encouraged to provide suggestions for improvements through our website. The following types of feedback are actively sought:

suggest a question

Suggest Questions or Problem Sets

Readers may have a suggestion for a question or problem set to be included in the tutorial of an existing chapter. This may be particularly useful for teachers of cardiovascular physiology or cardiology courses.

Suggest a Question or Set

suggest a chapter

Suggest a Chapter

The cardiovascular model employed in this textbook is versatile and faithfully simulates a large number of phyisologic phenomena. The currently available and planned chapters already cover a broad range of physiological and medically relevant topics. However, it is anticipated that readers may come up with suggestions for new chapters and lessons that can be added to the text.

Suggest a Chapter

report a bug

Report a Bug

As with any computer simulation, bugs may arise. Although extensive stress testing of the simulation has been performed, errors may be encountered with unusual combinations involving extreme values of system parameters.

Any such irregularities in model performance can be reported by following the "Report a Bug" link.

Report a Bug

Custom Apps

The model underlying the simulation is detailed and fairly well validated. It has been used to simulate numerous forms of cardiovascular disease and medical and device-based therapies. The simulation has been used to explain effects of different cardiovascular therapies, to prospectively predict the outcome of certain clinical trials and has been useful in guiding initial patient inclusion-exclusion criteria for new device-based therapies.

Readers interested in discussing the development of a custom app are encouraged to contact PVLoops via the Contact section.

custom apps