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A heart valve is a biological one-way valve that allows blood to flow in one direction through the chambers of the heart. A mammalian heart usually has four valves. Together, the valves determine the direction of blood flow through the heart. Heart valves are opened or closed by a difference in blood pressure on each side. [1] [2] [3]
Technicians who use ultrasound to examine the heart chambers, valves, and vessels are referred to as cardiac sonographers. [1] They use ultrasound instrumentation to create images called echocardiograms. An echocardiogram may be performed while the patient is either resting or physically active. Technicians may administer medication to ...
The semilunar valves close to prevent backflow into the heart. Since the atrioventricular valves remain closed at this point, there is no change in the volume of blood in the ventricle, so the early phase of ventricular diastole is called the isovolumic ventricular relaxation phase, also called isovolumetric ventricular relaxation phase. [1]
Congenital heart defects are divided into two main groups: cyanotic heart defects and non-cyanotic heart defects, depending on whether the child has the potential to turn bluish in color. [100] The problems may involve the interior walls of the heart, the heart valves, or the large blood vessels that lead to and from the heart. [99]
The concept of biomedical engineering was developed after World War II and they even considered it as they make humans work easier as they give exact and Clear detailed reports.The invention of the first artificial heart valve was successfully implanted in 1952, the first artificial kidney was created in the 1940s, and a heart-lung machine was ...
Cardiac catheterization (heart cath) is the insertion of a catheter into a chamber or vessel of the heart.This is done both for diagnostic and interventional purposes. A common example of cardiac catheterization is coronary catheterization that involves catheterization of the coronary arteries for coronary artery disease and myocardial infarctions ("heart attacks").
A heart rate below normal is called "bradycardia" (<60 in adults) and above normal is called "tachycardia" (>100 in adults). A complication of this is when the atria and ventricles are not in synchrony and the "heart rate" must be specified as atrial or ventricular (e.g., the ventricular rate in ventricular fibrillation is 300–600 bpm ...
Heart sounds result from vibrations created by the closure of the heart valves. There are at least two; the first (S1) is produced when the atrioventricular valves (tricuspid and mitral) close at the beginning of systole and the second (S2) when the aortic valve and pulmonary valve (semilunar valves) close at the end of systole. [ 4 ]