The Blood Pressure Distribution

We consider systems of differential equations behavior of which solutions possesses several properties characteristic of the blood pressure distribution. They are a result of compartmental modeling of the cardiovascular system, admit bounded solutions with all coordinates separated from zero by positive numbers, and which are periodic, eventually periodic, almost periodic or chaotic depending on the moments of heart contraction. There are several open problems for future investigation. First of all, they relate to arrhythmia and have to be supported with theoretical chaos investigation. Next are problems related to the artificial cardiac pacemaker optimization. We suppose that the study of synchronization of cardiac pacemaker will adjacent with this topic, eventually. The models have to be improved considering various type of discontinuities of solutions.