Your Heart Is An Amazing Organ
(BlackDoctor.org) Heart disease is the No. 1 killer of American men and women. But, it doesn’t have to be.
Heart failure affects some 4.6 million Americans. Roughly 550,000 people are diagnosed with heart failure each year. It is the leading cause of hospitalization in people older than 65. Your heart is an amazing organ. It continuously pumps oxygen and nutrient-rich blood throughout your body to sustain life. This fist-sized powerhouse beats (expands and contracts) 100,000 times per day, pumping five or six quarts of blood each minute, or about 2000 gallons per day. As the heart beats, it pumps blood through a system of blood vessels, called the circulatory system. The vessels are elastic tubes that carry blood to every part of the body.
Blood is essential. In addition to carrying fresh oxygen from the lungs and nutrients to your body’s tissues, it also takes the body’s waste products, including carbon dioxide, away from the tissues. This is necessary to sustain life and promote the health of all the body’s tissues.
There are three main types of blood vessels:
- Arteries: They begin with the aorta, the large artery leaving the heart. Arteries carry oxygen-rich blood away from the heart to all of the body’s tissues. They branch several times, becoming smaller and smaller as they carry blood farther from the heart and into organs.
- Capillaries: These are small, thin blood vessels that connect the arteries and the veins. Their thin walls allow oxygen, nutrients, carbon dioxide and other waste products to pass to and from our organ’s cells.
- Veins: These are blood vessels that take blood back to the heart; this blood lacks oxygen (oxygen-poor) and is rich in waste products that are to be excreted or removed from the body. Veins become larger and larger as they get closer to the heart. The superior vena cava is the large vein that brings blood from the head and arms to the heart, and the inferior vena cava brings blood from the abdomen and legs into the heart.
This vast system of blood vessels — arteries, veins and capillaries — is over 60,000 miles long. That’s long enough to go around the world more than twice! Blood flows continuously through your body’s blood vessels. Your heart is the pump that makes it all possible.
By Glenn Ellis, Executive Editor, BlackDoctor.Org
FDA Approves New Drug
The Food and Drug Administration (FDA) today approved Tyzeka
(telbivudine) for the treatment of adults with chronic hepatitis B (HBV), a
serious viral infection that attacks the liver and can cause lifelong infection,
scarring of the liver (cirrhosis), and eventually liver cancer, liver failure,
and death. Tyzeka is a new molecular entity, which is a term used by the FDA to
describe a medication containing an active substance that has never before been
approved for marketing in any form in the United States.
“In a typical year, an estimated 70,000 Americans become infected with
chronic HBV, and some 5,000 of them will die of the complications caused by the
disease,” said Dr. Steven Galson, Director of the Center for Drug Evaluation and
Research. “Tyzeka offers prescribers another option for treating these
Tyzeka was studied in a year-long international clinical trial in 1,367
patients with chronic HBV. Three-quarters of the trial participants were male,
and all were 16 years of age or older. The trial produced evidence of antiviral
effectiveness, including the suppression of hepatitis B virus, and improvement
in liver inflammation comparable to Epivir-HBV (lamivudine), one of five other
medications approved to treat patients with chronic HBV.
HBV is spread when blood from an infected person enters the body of a
person who is not infected, sometimes by sexual contact or blood contamination.
Tyzeka is not a cure for hepatitis B, and long-term treatment benefits of this
drug are not known. Use of Tyzeka has not been shown to reduce the risk of
transmission of HBV to others through sexual contact or blood
clinical studies Tyzeka was generally well tolerated, and most reported adverse
events were mild to moderate. The most common side effects were elevated CPK
(creatinine phosphokinase, an enzyme that is present in muscle tissue and is a
marker for breakdown of muscle tissue), upper respiratory tract infection,
fatigue, headache, abdominal pain and cough.
Also, after several weeks to months of Tyzeka use, some patients
developed symptoms ranging from transient muscle pain to muscle weakness. Those
who developed muscle weakness experienced significant improvement in their
symptoms when Tyzeka was discontinued.
Patients should only stop Tyzeka after a careful discussion with their
doctor. As has happened with other forms of treatment for hepatitis B, some
patients who discontinued Tyzeka experienced a sudden and severe worsening of
their hepatitis B. Therefore, patients who discontinue Tyzeka should be closely
monitored by their doctor for at least several months.
Among drugs in the same class as Tyzeka, some cases of lactic acidosis
(too much acid in the body due to buildup of lactic acid) and severe enlargement
and accumulation of fat in the liver, including fatal cases, have been
Tyzeka is manufactured by Novartis Pharma
Stein AG, Stein, Switzerland and marketed and distributed by Idenix
Pharmaceuticals, Inc., Cambridge, MA.