Quantitative integration of the cardiovascular system and synthesis of drug actions: another attempt.

This article describes the latest version of a computer program, first published in 1982, that attempts to integrate quantitatively the physiological and pharmacological knowledge of the cardiovascular system. This new version incorporates pressure-induced autoregulation of arterioles, distensibility of venous and pulmonary resistances, and some aspects of pericardial constraint on cardiac function. The program allows the researcher or student to explore the complex interactions resulting from changes in a wide variety of cardiovascular parameters and to synthesize the cardiovascular actions of drugs in the human, dog, or cat. The program can be run on an IBM-compatible computer with math coprocessor and with DOS as the operating system. The program can be modified by licensed users of QuickBasic. The program is available on diskette from the authors. This model represents our attempt to put together some of the complex interactions within the cardiovascular system. Every relationship, every initialized parameter, and every drug action can be questioned and alternatives can be proposed. However, the model allows these alternatives to be tested and their consequences to be predicted. We believe that the value of the model lies in the thought, discussion, and experiments that can be generated by this process.