WEDNESDAY, May 22, 2019 (HealthDay News) -- Imagine a procedure that filters "bad" LDL cholesterol from your bloodstream in a matter of hours.
The procedure, called LDL apheresis, works somewhat like kidney dialysis. Small amounts of blood are gradually removed from the body through an IV, then passed through a machine that removes LDL cholesterol.
Researchers found that when patients had the procedure a few days after a heart attack, it slashed their LDL levels within a few hours. Not only that, their artery-clogging "plaques" had shrunk by about 5% three months later.
Experts stressed the findings are preliminary, and the longer-term effects are not yet known.
"This study is not definitive," said lead researcher Dr. Subhash Banerjee, chief of cardiology at the VA North Texas Health Care System in Dallas. "It's an important step, but it's only a first step."
He was scheduled to present the findings Tuesday at the annual meeting of the Society for Cardiovascular Angiography and Interventions (SCAI), in Las Vegas. Research presented at meetings is typically considered preliminary until published in a peer-reviewed journal.
LDL apheresis has been around for years, but offered only to a limited group -- patients with a genetic condition called familial hypercholesterolemia, which causes very high LDL. Even then, it's done only when medications fail.
Banerjee's team wanted to see whether the procedure might also help in a much more common scenario: shortly after a heart attack.
"The idea was to not only bring patients' LDL down, but bring it down very quickly," Banerjee explained.
After a heart attack, he said, people are at high risk for another one -- often within a few months. In fact, American Heart Association figures show that 1 in 4 men and 1 in 3 women die within a year of suffering a heart attack -- in many cases, from a repeat attack.
To help cut those odds, high-dose statins are routinely prescribed to heart attack patients. They can be "very effective," Banerjee said, but many patients can't take high doses for a long period because of side effects.
In theory, apheresis might not only cut LDL levels; it might also allow patients to take lower statin doses to keep LDL numbers down. And that could limit side effects from the medications, Banerjee said.
To test the idea, his team enrolled 160 patients treated at four VA hospitals for an "acute coronary syndrome" -- either a heart attack or unstable angina, which is severe chest pain caused by blocked heart arteries.
All of the patients had stents implanted to help keep their narrowed heart arteries open, and all were prescribed statins. Within three days, half were randomly assigned to undergo LDL apheresis. The rest received statins only.
LDL apheresis worked quickly, according to Banerjee, slashing patients' LDL by 50% to 80% within two to three hours. Three months later, the plaques in those patients' arteries had shrunk by about 5.5%. In contrast, plaque volume rose in the statin-only group -- by 2.6%, on average.
"It's an indicator that they're on the right track," said Dr. Kirk Garratt, past president of SCAI.
Garratt, who was not involved in the study, said the use of LDL apheresis in this way is innovative.
But he said a big question remains: Can LDL apheresis ultimately prevent heart attacks or other cardiovascular complications such as stroke?
Banerjee agreed that question needs to be answered. He said the study, with funding from the VA, will follow patients out to a year, to see how they fare longer-term.
For now, the procedure -- which takes about three hours -- appears safe for these patients. There were no serious side effects, according to Banerjee. The main one was a temporary drop in blood pressure in some patients.
Still, apheresis would be an additional, and expensive, procedure for patients who've just had stents implanted, Garratt pointed out. So it will be important to show that it actually helps prevent future complications, he said.
Cost could vary across the country. For example, the University of Michigan's Frankel Cardiovascular Center in Ann Arbor offers LDL apheresis for patients who fail to respond to diet and drug therapy. Each treatment runs about $2,500 and most insurers cover that cost, according to its website.
The American Heart Association has more on heart attack recovery.