A typical heart has two upper and two lower chambers. The upper chambers, the right and left atria, receive incoming blood. The lower chambers, the more muscular right and left ventricles, pump …

Oct 22, 2025 · A normal resting heart rate for adults ranges from 60 to 100 beats per minute. A heart rate above or below that may signal a health condition.

Jun 4, 2025 · The heart's conduction system also is called the heart's electrical signaling system. Electrical signals start in a group of cells at the top of the heart called the sinus node. The signals tell …

Nov 4, 2023 · In heart valve surgery, a surgeon repairs or replaces the damaged or diseased heart valve or valves. Methods to do this may include open-heart surgery or minimally invasive heart surgery. …

Mar 18, 2025 · The heart and a primitive circulatory system will form in the middle layer of cells, called the mesoderm. This layer of cells also will serve as the foundation for the bones, ligaments, kidneys …

Jan 20, 2026 · You can help prevent heart disease by following a heart-healthy lifestyle. Here are strategies to help you protect your heart.

Jun 27, 2023 · Hoping to get an edge by taking performance-enhancing drugs? Learn how these drugs work and how they can have effects on your health.

Jun 11, 2024 · The heart then has to work harder to send blood to the rest of the body. Aortic valve repair and aortic valve replacement help improve blood flow and reduce symptoms of heart valve …

Jan 25, 2025 · Over time, free radical damage can cause problems for tissues and organs in the body, potentially leading to disease. Research suggests that free radical molecules can add to the risk of …

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