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 physicians at Washington University School of Medicine in St. Louis can help these patients with a technique called LDL aphersis.
They are offering treatment at Barnes-Jewish Hospital with an FDA-approved system known as HELP (Heparin-induced Extracorporeal Lipoprotein Precipitation), which filters LDL cholesterol out of the blood.
“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,” says Washington University cholesterol specialist 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. 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), which is caused by a mutation in the LDL receptor gene. The condition affects about one in every 500 people.
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. People with FH have a high risk of suffering a heart attack or a stroke, often at a young age.
“High levels of cholesterol cause deposits to form inside blood vessels, and those deposits, called plaques, can narrow arteries and block blood flow,” Goldberg says. “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.
“These are people where normal therapy either isn’t working well enough, or they can’t tolerate enough therapy to get their bad cholesterol levels down,” says Goldberg.
A few dozen centers in the United States offer LDL apheresis, but the Center for Advanced Medicine at Washington University and Barnes-Jewish Hospital is the only site in the St. Louis area. The nearest centers to St. Louis offering the therapy are in Kansas City, Cincinnati and Indianapolis.
Goldberg says 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,” she explains. “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, call 314-362-3500.
Washington University School of Medicine’s 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked third in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.