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ICDs are useful in preventing sudden death in patients with known, sustained ventricular tachycardia or fibrillation. Studies have shown ICDs to have a role in preventing cardiac arrest in high-risk patients who haven't had, but are at risk for, life-threatening ventricular arrhythmias. View an animation of an ICD. Newer-generation ICDs may have a dual function which includes the ability to serve as a pacemaker. The pacemaker feature would stimulate the heart to beat if the heart rate is detected to be too slow. What is an Implantable Cardioverter Defibrillator (ICD)? An ICD is a battery-powered device placed under the skin that keeps track of your heart rate. Thin wires connect the ICD to your heart. If an abnormal heart rhythm is detected the device will deliver an electric shock to restore a normal heartbeat if your heart is beating chaotically and much too fast. ICDs have been very useful in preventing sudden death in patients with known, sustained ventricular tachycardia or fibrillation. Studies have shown that they may have a role in preventing cardiac arrest in high-risk patients who haven't had, but are at risk for, life-threatening ventricular arrhythmias.
Wilson's disease is a rare inherited disorder that causes too much copper to accumulate in your liver, brain and other vital organs. Symptoms typically begin between the ages of 12 and 23. Copper plays a key role in the development of healthy nerves, bones, collagen and the skin pigment melanin. Normally, copper is absorbed from your food, and any excess is excreted through bile — a substance produced in your liver. But in people with Wilson's disease, copper isn't eliminated properly and instead accumulates, possibly to a life-threatening level. When diagnosed early, Wilson's disease is treatable, and many people with the disorder live normal lives.
The human heart has four main valves—two on the left and two on the right. The aortic valve is one of the main valves on the left side of the heart. It is the outflow valve for the left ventricle, which means that it is the valve between the heart and the body. The aortic valve opens when the left ventricle squeezes to pump out blood, and closes in between heart beats to keep blood from going backward into the heart.
Tendons are thick cords that join your muscles to your bones. When these tendons become irritated or inflamed, it is called tendinitis. This condition causes acute pain and tenderness, making it difficult to move the affected joint. Read more
The cornea occupies the front center part of the outer wall of the eye. It is made of collagen fibers in a very special arrangement so that the cornea is clear. One looks through the cornea to see the iris and pupil. The cornea bends light coming into the eye so that it is focused on the retina.
Cells may have slender extensions of the cell membrane to form cilia or the smaller extensions called microvilli. The microscopic microvilli effectively increase the surface area of the cell and are useful for absorption and secretion functions. A dramatic example is the human small intestine. The tissue has small fingerlike extensions called villi which are collections of cells, and those cells have many microvilli to even further increase the available surface area for the digestion process. According to Audesirk & Audesirk, this can give an effective surface area of about 250 square meters for absorption.
The term trisomy is used to describe the presence of three chromosomes, rather than the usual matched pair of chromosomes. For example, if a baby is born with three #21 chromosomes, rather than the usual pair, then the baby would be said to have "trisomy 21." Trisomy 21 is also known as Down syndrome. Other examples of trisomy include syndromes like trisomy 18 and trisomy 13. Again, trisomy 18 or trisomy 13 simply means the child has three copies of the #18 chromosome (or of the #13 chromosome) present in each cell of the body, rather than the usual pair.
The timing of the nausea or vomiting can indicate the cause. When appearing shortly after a meal, nausea or vomiting may be caused by food poisoning, gastritis (inflammation of the stomach lining), an ulcer, or bulimia. Nausea or vomiting one to eight hours after a meal may also indicate food poisoning.
Nephrotic syndrome is a kidney disorder that causes your body to excrete too much protein in your urine. Nephrotic syndrome is usually caused by damage to the clusters of small blood vessels in your kidneys that filter waste and excess water from your blood. Nephrotic syndrome causes swelling (edema), particularly in your feet and ankles, and increases the risk of other health problems. Treatment for nephrotic syndrome includes treating the underlying condition that's causing it and taking medications. Nephrotic syndrome can increase your risk of infections and blood clots. Your doctor may recommend medications and dietary changes to prevent these and other complications of nephrotic syndrome.
Iatrogenic injury to the ureter is a potentially devastating complication of modern surgery. The ureters are most often injured in gynecologic, colorectal, and vascular pelvic surgery. There is also potential for considerable ureteral injury during endoscopic procedures for ureteric pathology such as tumor or lithiasis. While maneuvers such as perioperative stenting have been touted as a means to avoid ureteral injury, these techniques have not been adopted universally, and the available literature does not make a case for their routine use. Distal ureteral injuries are best managed with ureteroneocystostomy with or without a vesico-psoas hitch. Mid-ureteral and proximal ureteral injuries can potentially be managed with ureteroureterostomy. If the distal segment is unsuitable for anastomosis then a number of techniques are available for repair including a Boari tubularized bladder flap, transureteroureterostomy, or renal autotransplantation. In rare cases renal autotransplantation or ureteral substitution with gastrointestinal segments may be warranted to re-establish urinary tract continuity. Laparoscopic and minimally invasive techniques have been employed to remedy iatrogenic ureteral injuries.
As a result, the amount of glucose in the blood increases while the cells are starved of energy. Over time, high blood glucose levels damage nerves and blood vessels, leading to complications such as heart disease and stroke, the leading causes of death among people with diabetes.