INFLAMMATIONS IN THE HEART.
These are among the most common diseases of this organ and moreover lead to many of the changes in structure to be hereafter noticed so that it is convenient to treat of them here. According to their relative frequency they may be ranged:—1st. Inflammation of the external covering of the heart—pericarditis; 2d. Inflammation of the internal lining membrane of the heart—endocarditis; and 3d. Inflammation of the muscular substance of the heart—carditis.