In the letters that follow, the heart, addressing the brain, refers to this unfair and unjustified attribution of qualities that do not belong to it, as well as the corresponding shift of responsibilities, while clearly and simply expressing its complaints and needs to the brain, placing it before its responsibilities.

Thus, in ten letters and an "epilogue," fundamental topics concerning the normal functioning of the heart (and blood vessels) are presented in a simple, popularized manner, and the main factors contributing to the onset of coronary artery disease are mentioned, for which, of course, the brain is responsible (with its desires, choices, and decisions).

While in footnotes, in each letter, there is a brief scientific presentation and documentation of the corresponding topic of the letter.