https://tube.blueben.net/videos/watch/dbe8e3b9-cee3-4eaa-9ec5-792a6ae73e3d What Makes Your Heartbeat Sound Every heartbeat makes the familiar lub-dub sound, but it isn’t caused by the heart muscle squeezing. “Lub” comes from the mitral and tricuspid valves closing, while “dub” comes from the aortic and pulmonary valves shutting as blood flow changes. Mon, 05 Oct 2026 17:06:14 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://tube.blueben.net https://tube.blueben.net/client/assets/images/icons/icon-96x96.png https://tube.blueben.net/videos/watch/dbe8e3b9-cee3-4eaa-9ec5-792a6ae73e3d All rights reserved, unless otherwise specified in the terms specified at https://tube.blueben.net/about and potential licenses granted by each content's rightholder.