What is intracranial atherosclerosis? Intracranial simply means âinside the skull.â Atherosclerosis is a hardening of the arteries. So, intracranial atherosclerosis is a narrowing and hardening of the arteries in the skull. Generally there are no symptoms until the arteries are so clogged with plaque that blood can no longer flow through them.
According to Baby Center, is possible to hear the baby's heartbeat at about 8 weeks via ultrasound. A fetus's heartbeat begins at about 6 weeks gestation.
Put your head on someone's chest and the heartbeat sounds a bit like lub-DUB, lub-DUB, lub-DUB. The lub is the sound of the tricuspid and mitral valves closing. The DUB is the sound of the aortic and pulmonary valves closing. Together, they're the sound of someone's heart doing its job.