The interplay between heart and brain is bi-directional, complex and profound. Each system influences the other in health as well as in disease, when dysfunction in one organ has broad and as yet incompletely understood reverberations on the other. Although terms such as “heart-brain axis,” “brain-heart axis,” and “brain-heart syndrome” have previously been used to describe the complex interaction between the heart and the brain, a unified and systematic conceptual framework for coherently classifying these various clinical conditions is currently lacking.
