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Pulsus Bisferiens
Pulsus bisferiens, also known as biphasic pulse, is an aortic waveform with two peaks per cardiac cycle, a small one followed by a strong and broad one. This reference illustrates the normal and abnormal spectral waveform. It is a sign (medicine), sign of problems with the aortic valve, aorta, including aortic stenosis and aortic regurgitation, as well as hypertrophic cardiomyopathy causing subaortic stenosis. __TOC__ Pathogenesis In hypertrophic cardiomyopathy, there is narrowing of the left ventricular outflow tract (LVOT) due to hypertrophy of the interventricular septum. During systole, the narrowing of the LVOT creates a more negative pressure due to the Venturi effect and sucks in the anterior mitral valve leaflet. This creates a transient occlusion of the LVOT, causing a midsystolic dip in the aortic waveform. Towards the end of systole, the ventricle is able to overcome the obstruction to cause the second rise in the aortic waveform. In severe aortic regurgitation, addit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiology
Cardiology () is a branch of medicine that deals with disorders of the heart and the cardiovascular system. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. Physicians who specialize in this field of medicine are called cardiologists, a specialty of internal medicine. Pediatric cardiologists are pediatricians who specialize in cardiology. Physicians who specialize in cardiac surgery are called cardiothoracic surgeons or cardiac surgeons, a specialty of general surgery. Specializations All cardiologists study the disorders of the heart, but the study of adult and child heart disorders each require different training pathways. Therefore, an adult cardiologist (often simply called "cardiologist") is inadequately trained to take care of children, and pediatric cardiologists are not trained to treat adult heart disease. Surgical aspects are not included in cardiology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiac Cycle
The cardiac cycle is the performance of the human heart from the beginning of one heartbeat to the beginning of the next. It consists of two periods: one during which the heart muscle relaxes and refills with blood, called diastole, following a period of robust contraction and pumping of blood, called systole. After emptying, the heart immediately relaxes and expands to receive another influx of blood returning from the lungs and other systems of the body, before again contracting to pump blood to the lungs and those systems. A normally performing heart must be fully expanded before it can efficiently pump again. Assuming a healthy heart and a typical rate of 70 to 75 beats per minute, each cardiac cycle, or heartbeat, takes about 0.8 second to complete the cycle. There are two atrial and two ventricle chambers of the heart; they are paired as the left heart and the right heart—that is, the left atrium with the left ventricle, the right atrium with the right ventricle—and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sign (medicine)
Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showing on a medical scan. A symptom is something out of the ordinary that is experienced by an individual such as feeling feverish, a headache or other pain or pains in the body. Signs and symptoms Signs A medical sign is an objective observable indication of a disease, injury, or abnormal physiological state that may be detected during a physical examination, examining the patient history, or diagnostic procedure. These signs are visible or otherwise detectable such as a rash or bruise. Medical signs, along with symptoms, assist in formulating diagnostic hypothesis. Examples of signs include elevated blood pressure, nail clubbing of the fingernails or toenails, staggering gait, and arcus senilis and arcus juvenilis of the eyes. Indication ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aortic Valve
The aortic valve is a valve in the heart of humans and most other animals, located between the left ventricle and the aorta. It is one of the four valves of the heart and one of the two semilunar valves, the other being the pulmonary valve. The aortic valve normally has three cusps or leaflets, although in 1–2% of the population it is found to congenitally have two leaflets. The aortic valve is the last structure in the heart the blood travels through before stopping the flow through the systemic circulation. Structure The aortic valve normally has three cusps however there is some discrepancy in their naming. They may be called the left coronary, right coronary and non-coronary cusp. Some sources also advocate they be named as a left, right and posterior cusp. Anatomists have traditionally named them the left posterior (origin of left coronary), anterior (origin of the right coronary) and right posterior. The three cusps, when the valve is closed, contain a sinus called an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aortic Stenosis
Aortic stenosis (AS or AoS) is the narrowing of the exit of the left ventricle of the heart (where the aorta begins), such that problems result. It may occur at the aortic valve as well as above and below this level. It typically gets worse over time. Symptoms often come on gradually with a decreased ability to exercise often occurring first. If heart failure, loss of consciousness, or heart related chest pain occur due to AS the outcomes are worse. Loss of consciousness typically occurs with standing or exercising. Signs of heart failure include shortness of breath especially when lying down, at night, or with exercise, and swelling of the legs. Thickening of the valve without narrowing is known as aortic sclerosis. Causes include being born with a bicuspid aortic valve, and rheumatic fever; a normal valve may also harden over the decades. A bicuspid aortic valve affects about one to two percent of the population. As of 2014 rheumatic heart disease mostly occurs in the dev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aortic Regurgitation
Aortic regurgitation (AR), also known as aortic insufficiency (AI), is the leaking of the aortic valve of the heart that causes blood to flow in the reverse direction during ventricular diastole, from the aorta into the left ventricle. As a consequence, the cardiac muscle is forced to work harder than normal. Signs and symptoms Symptoms of aortic regurgitation are similar to those of heart failure and include the following: * Dyspnea on exertion * Orthopnea * Paroxysmal nocturnal dyspnea * Palpitations * Angina pectoris * Cyanosis (in acute cases) Causes In terms of the cause of aortic regurgitation, is often due to the aortic root dilation ('' annuloaortic ectasia''), which is idiopathic in over 80% of cases, but otherwise may result from aging, syphilitic aortitis, osteogenesis imperfecta, aortic dissection, Behçet's disease, reactive arthritis and systemic hypertension.Chapter 1: Diseases of the Cardiovascular system > Section: Valvular Heart Disease in: Aortic root dilation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypertrophic Cardiomyopathy
Hypertrophic cardiomyopathy (HCM, or HOCM when obstructive) is a condition in which the heart becomes thickened without an obvious cause. The parts of the heart most commonly affected are the interventricular septum and the ventricles. This results in the heart being less able to pump blood effectively and also may cause electrical conduction problems. People who have HCM may have a range of symptoms. People may be asymptomatic, or may have fatigue, leg swelling, and shortness of breath. It may also result in chest pain or fainting. Symptoms may be worse when the person is dehydrated. Complications may include heart failure, an irregular heartbeat, and sudden cardiac death. HCM is most commonly inherited from a person's parents in an autosomal dominant pattern. It is often due to mutations in certain genes involved with making heart muscle proteins. Other inherited causes of left ventricular hypertrophy may include Fabry disease, Friedreich's ataxia, and certain medica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Left Ventricular Outflow Tract
A ventricular outflow tract is a portion of either the left ventricle or right ventricle of the heart through which blood passes in order to enter the great arteries. The right ventricular outflow tract (RVOT) is an infundibular extension of the ventricular cavity that connects to the pulmonary artery. The left ventricular outflow tract (LVOT), which connects to the aorta, is nearly indistinguishable from the rest of the ventricle. The outflow tract is derived from the secondary heart field, during cardiogenesis. Both the left and right outflow tract have their own term. The right outflow tract is called "conus arteriosus" from the outside, and infundibulum from the inside. In the left ventricle the outflow tract is the "aortic vestibule". They both possess smooth walls, and are derived from the embryonic bulbus cordis In both left and right ventricle there are specific structures separating the inflow and outflow of blood. In the right ventricle, the inflow and outflow is separ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interventricular Septum
The interventricular septum (IVS, or ventricular septum, or during development septum inferius) is the stout wall separating the ventricles, the lower chambers of the heart, from one another. The ventricular septum is directed obliquely backward to the right and curved with the convexity toward the right ventricle; its margins correspond with the anterior and posterior interventricular sulci. The lower part of the septum, which is the major part, is thick and muscular, and its much smaller upper part is thin and membraneous. During each cardiac cycle the interventricular septum contracts by shortening longitudinally and becoming thicker. Structure The interventricular septum is the stout wall separating the ventricles, the lower chambers of the heart, from one another. The ventricular septum is directed obliquely backward to the right and curved with the convexity toward the right ventricle; its margins correspond with the anterior and posterior longitudinal sulci. The gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venturi Effect
The Venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section (or choke) of a pipe. The Venturi effect is named after its discoverer, the 18th century Italian physicist, Giovanni Battista Venturi. Background In inviscid fluid dynamics, an incompressible fluid's velocity must ''increase'' as it passes through a constriction in accord with the principle of mass continuity, while its static pressure must ''decrease'' in accord with the principle of conservation of mechanical energy (Bernoulli's principle). Thus, any gain in kinetic energy a fluid may attain by its increased velocity through a constriction is balanced by a drop in pressure. By measuring pressure, the flow rate can be determined, as in various flow measurement devices such as Venturi meters, Venturi nozzles and orifice plates. Referring to the adjacent diagram, using Bernoulli's equation in the special case of steady, incompressible, inviscid flows (such as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
