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The heart is an extraordinary pump designed by nature to maintain circulation of blood in the body. Physiological functions, namely contractions and relaxations of the heart muscles, are mediated by electrical signals. This electrical activity when recorded as a graph of moving lines on a strip chart is called an electrocardiogram (EKG/ECG). Tiny electrodes are attached to specific sites on the chest and limbs of an individual and waves of electrical signals are gathered for display. It is a very powerful tool which provides a wealth of information.
A miniaturized portable electrocardiographic machine which records a heart's electrical activity while a patient is freely ambulating, can be utilized to continuously monitor a patient for 24 hours or even for several days, and is called a Holter.
Echocardiography relies on ultrasound energy, which is reflected off the structures of the heart, to produce pictures. The chambers of the heart, as well as their walls, and valves that guide the flow of blood within the heart are displayed on an imaging platform. The major blood vessels attached to the heart can also be visualized. It does not use X-ray and is a very safe test. A special gel is necessary and is placed on the chest, as the pictures are taken by a hand held transducer and displayed on a video monitor.
This is a common physiological test which can bring out abnormalities of heart function that are not commonly present at rest. It can estimate functional capacity, predict underlying coronary artery disease and elicit rhythm disturbances with reasonable accuracy. In its simplest form, it is done by exercising a person to target heart rate and by recording 12 lead electrocardiograms during the process. In patients who are unable to exercise due to physical limitations, infusion of pharmacological agents like Dobutamine may simulate exercise by raising a person's heart rate by chemical means.
Arteries and veins in the body can similarly be imaged with ultra sound to detect various forms of vascular disease. Early detection leads to effective preventative interventions or treatment strategies.
Carotid arteries: These are two arteries in the neck that provide blood supply to the head and neck. Plaque information within these vessels by the process of atherosclerosis significantly increases the risk of strokes.
Peripheral arteries of the lower extremities: Compromised circulation to the lower extremities causes cramping pain in the legs when walking and is called claudication. Advanced disease may threaten the viability of a person's legs.
Aorta: Atherosclerosis is a widely preventative disease process that affects a very large percentage of people in this country and world wide. It is a result of infiltration of the lining of blood vessels with cholesterol rich fatty plaques that disrupt flow of blood. Weakened areas of such vessels may lose their elasticity and form aneurismal dilations, which can be dangerous if they rupture.
Renal: Compromised circulation to the kidneys, from obstructive disease in the renal arteries, is an important cause of very high blood pressure.
Venous disorders: Disease in the peripheral venous systems (particularly in the lower extremities) can be easily diagnosed with ultrasound based duplex imaging. Acute Deep Vein Thrombosis (DVT) can pose a very significant hazard to a person's health profile.
Non-invasive tests using ultrasound techniques to examine the carotid arteries and other blood vessels.
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