Treatment filters out bad cholesterol

Diet and lifestyle changes, combined with medication, can lower the risk of heart attack and stroke in patients with high levels of so-called bad cholesterol. But some patients genetically predisposed to high levels of LDL (low-density lipoprotein) don’t respond well to drug therapy.

Now School of Medicine physicians can help these patients with a technique called LDL apheresis, a treatment with an FDA-approved system known as HELP (Heparin-induced Extracorporeal Lipoprotein Precipitation), which filters LDL cholesterol out of the blood.

Anne Carol Goldberg, M.D., associate professor of medicine, talks with patient Ted Harrison while he undergoes apheresis treatment for high cholesterol at Barnes-Jewish Hospital.

“The blood is separated into red cells and plasma, and the plasma is run through a device containing material that grabs on to bad cholesterol particles,” said Anne Carol Goldberg, M.D., associate professor of medicine. “It picks up the particles that contain a protein found on LDL cholesterol and removes them from the blood. Then the plasma is put back together with the red blood cells, minus the LDL, and returned to the body.”

The therapy reduces LDL cholesterol levels by at least 50 percent, according to Goldberg, a cholesterol specialist. Sometimes as much as three quarters of a patient’s LDL will be removed during treatment. Unfortunately, the bad cholesterol will begin to build up again in the days and weeks following treatment, so patients who qualify for the therapy must receive treatment twice a month.

The HELP system is designed primarily for people with inherited genetic defects that cause their LDL levels to be extremely high. Most have been diagnosed with Familial Hypercholesterolemia (FH), caused by a mutation in the LDL receptor gene. The condition affects about one in every 500 people. People with FH have a high risk of suffering a heart attack or a stroke, often at a young age.

Some people with very severe FH will inherit a defective gene from both parents, but that only occurs about once in every 1 million people. In patients with one defective copy of the gene, blood cholesterol levels usually range between 350 and 500. Those with two copies of the defective gene can have cholesterol levels between 700 and 1,200.

“High levels of cholesterol cause deposits to form inside blood vessels, and those deposits, called plaques, can narrow arteries and block blood flow,” Goldberg said. “It is a silent disease, and most people don’t notice any symptoms until they suffer a heart attack or a stroke.”

To be eligible for the therapy, a person must have an LDL cholesterol level of more than 300 after at least six months of drug treatment to lower cholesterol and lifestyle changes, including a diet low in saturated fat with low-cholesterol foods. People who already have been diagnosed with cardiovascular disease are eligible if their LDL levels remain above 200 after maximum tolerated therapy.

A few dozen centers in the United States offer LDL apheresis, but the Center for Advanced Medicine at the School of Medicine and Barnes-Jewish Hospital is the only site in the St. Louis area. Other centers close to St. Louis offering the therapy are in Kansas City, Mo., Cincinnati and Indianapolis.

Goldberg said unlike kidney dialysis, which removes impurities from the blood of patients who have kidney failure, LDL apheresis is more like what happens when people donate platelets at the blood bank.

“This does not remove as much blood for as long a period of time. It’s a shorter procedure,” Goldberg said. “On dialysis, it’s possible for a patient to develop imbalances in things like potassium or sodium. That’s not the situation with this treatment because basically the only thing we’re taking out of the blood is LDL.”

Each session involves the treatment of up to three quarts of blood plasma. Patients also must continue their diet and drug therapy.

For more information on the procedure, call 362-3500.