In its classic definition, by FranÃ§ois-Louis Ganshof (1944), feudalism describes a set of reciprocal legal and military obligations among the warrior nobility revolving around the three key concepts of lords, vassals and fiefs.
The exact cause of intracardiac echogenic foci remains unclear; however, they appear to be caused by small deposits of calcium in the papillary muscle of the fetal heart.
Echocardiography is the main diagnostic tool used in the evaluation of pericardial effusion. A pericardial effusion causes an echo-free space between visceral and parietal pericardium; the extent of the space defines the size of the effusion (Table 3). Large effusions can produce the picture of a swinging heart.