Data from: Recurrent myocardial infarction: mechanisms of free-floating adaptation and autonomic derangement in networked cardiac neural control

The cardiac nervous system continuously controls cardiac function whether
or not pathology is present. While myocardial infarction typically has a
major and catastrophic impact, population studies have shown that
longer-term risk for recurrent myocardial infarction and the related
potential for sudden cardiac death depends mainly upon standard
atherosclerotic variables and autonomic nervous system maladaptations.
Investigative neurocardiology has demonstrated that autonomic control of
cardiac function includes local circuit neurons for networked control
within the peripheral nervous system. The structural and adaptive
characteristics of such networked interactions define the dynamics and a
new normal for cardiac control that results in the aftermath of recurrent
myocardial infarction and/or unstable angina that may or may not
precipitate autonomic derangement. These features are explored here via a
mathematical model of cardiac regulation. A main observation is that the
control environment during pathology is an extrapolation to a setting
outside prior experience. Although global bounds guarantee stability, the
resulting closed-loop dynamics exhibited while the network adapts during
pathology are aptly described as ‘free-floating’ in order to emphasize
their dependence upon details of the network structure. The totality of
the results provide a mechanistic reasoning that validates the clinical
practice of reducing sympathetic efferent neuronal tone while aggressively
targeting autonomic derangement in the treatment of ischemic heart
disease.