During heart treatment performed via a port, the heart is moved without impeding the circulatory dynamics in the cardiac sac. Provided is a cardiac treatment apparatus including: an annular portion equipped with a wire that can be deformed between a contracted shape that allows insertion into the cardiac sac via a tubular port disposed passing from a body surface to the pericardium and an annular expanded shape in which the annular portion is expanded in the cardiac sac, is fitted onto the outer circumference of the heart from a ventricular apex side, and is located at a position for surrounding the outer circumference of the heart and a pulling portion that exerts a pulling force on the annular portion such that the annular portion presses a sidewall of the heart, with the annular portion having been located at the position for surrounding the heart.
