'grave heart' is not an expression that is commonly used in written English.
If you wanted to express a serious or sombre feeling, you could say "a heavy heart" instead. For example: "She carried her heavy heart as she said her final goodbye."
The final section is a different irony and the book's grave heart.
Rumors have it that Yanukovych has been confined to a hospital after a grave heart attack; the uncertainty has led to open speculation that he might even be dead.
From 1948 to 1954, while strep infections raged at the Fort Francis E. Warren Air Force Base in Wyoming, doctors there conducted a landmark study that eventually proved that treating the bacterial infections with antibiotics could prevent rheumatic fever, a grave heart condition that can follow strep throat.
The film climaxes with our down-to-earth anti-hero (whose endeavours have touched an entire community) suffering dramatic crucifixion and death, only for his body to escape the grave via heart and eye transplants which restore sight to the blind and offer the gift of new life.
Me, I blushed at the grimly determined image of the Hong Kong actor Tony Leung Chiu-Wai, the great, grave, soulful heart of Wong Kar-wai films like "In the Mood for Love" and "2046," bunching up the sheets as this new film's resident villain and cad.
In each of the rose arches a passageway opens, like the entrance to a garden, to a grave, to the heart of a flower.
All that they had they gave - they gave; and they shall not return./ For these are those that have no grave where any heart may mourn.
Leicester notes that it is a couple of hours away by horse from where Richard was killed in 1485, at the Battle of Bosworth Field, and that he lay for centuries in a shallow grave in the heart of the city.
But for all the joy and mania surrounding the N.F.L. game, for all the spectacle and the glorious noise outside it and for all the systems and salesmanship and money within it, there is still something human and grave at the heart of professional football, something frightening in its zero-sum tally of risk and defeat.
There was not a moist eye in the land when his metal-plated coffin, while in the televised process of being lowered into the grave, in the very heart of the heart of the country, suddenly proved to be too heavy for the funeral servants' hands and tumbled into the hole with a loud crashing sound.
Years later, three of the observers eventually died of conditions that are known to be promoted by radiation (Graves of a heart attack 20 years later at age 54, Cieslicki of acute myelocytic leukemia 19 years later at age 42, and Young of aplastic anemia and bacterial infection of the heart lining 27 years later at age 83).
