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Patient Education
General Cardiology
The Heart
In the course of a lifetime, a human heart can beat over two million times. The heart's sturdy, rhythmic beating to constantly nourish the body's tissues and organs belies the fact that the heart is an incredibly complex, intricate organ.
The heart is composed of specially organized tissue surrounding a cartilage foundation. The heart is divided into four chambers, composed of the left and right atria, and the left and right ventricles. A sophisticated valve system controls blood flow between the chambers. In fact, it is the latching of the heart valves that creates the beating sound of the heart.
De-oxygenated blood from the body tissues enters the heart in the right atrium. When the atria contract, the blood is ejected into the right ventricle. Upon contraction of the ventricles, the blood moves from the right ventricle through the pulmonary arteries, where it absorbs oxygen inhaled into the lungs. Oxygenated blood returns via the pulmonary veins and empties into the left atrium. When the heart contracts again, blood moves into the left ventricle. Upon left ventricular contraction, the oxygen-rich blood is pumped through the aorta, from which it is distributed throughout the tissues to provide oxygen and other nutrients to the body.
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Cardiac muscle contract in a highly coordinated fashion to repeatedly eject large volumes of blood into the cardiovascular system. Such contractions are coordinated by an intricate electrical signaling system. A specialized group of cells in the right atrium, called the Sino-Atrial Node (SA Node) initiate the electrical signal. As the electrical signal disseminates through the heart tissue, contraction occurs along its path. When the electrical signal reaches the wall between the atria and ventricles, it must pass through another specialized bundle of tissue, called the Atrial-Ventricular Node (AV Node). Once the electrical signal passes through the AV Node, it propagates through the ventricles and stimulates ventricular contraction. Immediately after stimulating contraction normal cardiac tissue is unable to be stimulated by another electrical impulse - this phenomena is called hyperpolarization - maintaining the unidirectional flow of the electrical current. Within milliseconds, hyperpolarized cardiac tissue returns back to its baseline electrochemical state, ready to contract upon the arrival of the next signal.
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An electrocardiogram (EKG) diagnostic test is often performed to evaluate a patient's electrical heart activity. It provides cardiologists with a blueprint of the propagation of the electrical signal within different regions of the heart.
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Many complex feedback and control mechanisms are naturally in place to maintain cardiovascular homeostasis. Heart rate and blood flow are constantly adjusted according to exercise, environment, stress, and other factors.
Heart Disease
The human heart is incredibly efficient and durable, given its intricacy and workload. However, the heart is prone to damage from environmental, genetic, age-related, and disease-related factors. Common risk factors include smoking, high-cholesterol diets, diabetes, hypertension, and lack of exercise. According to the Centers for Disease Control and Prevention (CDC), Heart Disease is the most common cause of death in the United States, accounting for over 650,000 deaths per year. Heart problems can be a challenge to live with. They often demand comprehensive medical care, bring about drastic lifestyle changes, and affect the lives of friends and family.
The USC Division of Cardiovascular Medicine understands the strain that cardiac problems can have on patients and their loved ones. We understand that such problems can be daunting, and work tirelessly to make the experiences of our patients a positive one.
The USC Division of Cardiovascular Medicine is made up of talented physicians and staff from all corners academic and medical worlds. They are tremendously involved in research to push the boundaries of cardiac care and lay the foundation for the treatments of tomorrow. They are highly decorated as members of many professional societies and are recognized as pioneers in the field. Our wide-ranging team of specialists will work together to create the best solution to our patients' needs, utilizing an array of medication, lifestyle, and procedural therapies. At the USC Division of Cardiovascular Medicine we will do whatever it takes to allow our patients to live life to the fullest.
The USC Division of Cardiovascular Medicine has at its disposal a talented and diverse staff, and a plethora of cutting edge technologies to provide optimal care for our patients. The USC Division of Cardiovascular Medicine is proud to provide our patients with access to leading professionals in the cardiac specialties of:
At the USC Division of Cardiovascular Medicine we welcome our patients into the Trojan family.
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