Heart valve chambers are lined with endocardium. Heart valves separate the atria from the ventricles, or the ventricles from a blood vessel. Heart valves are situated around the fibrous rings of the cardiac skeleton. The valves incorporate leaflets or cusps, which are pushed open to allow blood flow and which then close together to seal and prevent backflow. The mitral valve has two cusps, whereas the others have three. There are nodules at the tips of the cusps that make the seal tighter. The pulmonary valve has left, right, and anterior cusps. The aortic valve has left, right, and posterior cusps. The
Any Human Heart Any Human Heart Any Human Heart: The Intimate Journals of Logan Mountstuart is a 2002 novel by William Boyd, a British writer. It is written as a lifelong series of journals kept by Mountstuart, a writer whose life (1906–1991) spanned the defining episodes of the 20th century, crossed several continents and included a convoluted sequence of relationships and literary endeavours. Boyd uses the diary form to explore how public events impinge on individual consciousness, so that Mountstuart's journal alludes almost casually to the war, the death of a prime minister or the abdication of the king. Boyd plays ironically on