The term heart is often mentioned in Vedantic scriptures.  However, the term is not used in a physiological sense but rather in a psychological one as in the heart of the issue or the heart of a nation. In Advaita Vedanta heart has a very specific metaphysical meaning but also many divergent explanations of that meaning that one might just as well concentrate on the physiological heart.

There is, however, one definition that perfectly elucidates the Vedantic meaning of heart.

In his commentary on the Bhagavad Gita, Chapter 15, Verse 15, referring to the line, “I am seated in the hearts of all,” H. H. Swami Chinmayananda wrote:

“The term HEART in philosophy means ‘minds which have been trained to entertain constantly the positive qualities of love, tolerance, mercy, charity, kindness, and the like.’ A peaceful, joyous settled in tranquility, alert and vigilant to receive higher intimations is called the ‘heart.’

The Infinite ‘DWELLS IN THE HEART’ means, though He is present everywhere the Lord is most conspicuously self-evident, during meditation, in the HEART of the meditator.”

So, as Gurudev has pointed out, the term heart refers to the mind and a very special kind of trained mind.  And Vedanta tells us that the mind is not a part of the body.  Many associate the term mind with the brain, which is in the body. Both body and brain are composed of gross physical matter. The mind, however, is composed of subtle matter, and, if anything, one could say the body and its brain exist within the mind and not vice versa.