1998 Cardiovascular Diseases Lecture 1




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Summary: The heart acts as a dual pump, sending oxygen-depleted blood to the lungs to be reinvigorated and pumping oxygen-rich blood to vital organs throughout the body. A collection of specialized cells, called the pacemaker, coordinates the contraction of the heart’s four chambers by generating electrical impulses that spread all over the heart. Hormonal secretions alter heart activity in various ways, as can risk factors such as smoking and male gender.