Scientists develop tiny tech to tackle heart attacks

Most vulnerable could benefit from new technology that will dissolve the plaques that lead to blocked blood vessels.

New technology targets the plaque that can cause heart attacks. Picture; Thinkstock.

Scientists are developing technology that seeks out and destroys the deadly blockages that cause thousands of heart attacks a year.

The treatment, which scientists believe could be given to patients in as little as three years, uses a nanoparticle that identifies and latches on to the most dangerous plaques in blood vessels near the heart. A tiny capsule – just a 5,000th of a millimetre in size – releases an anti-inflammatory medicine, breaking down the plaque and slashing the risk of a heart attack.

The approach, developed by researchers at Imperial College London, marks a radical departure in the treatment of coronary arterial disease – the primary cause of heart attacks – which kills about 66,000 people a year.

For years, those at risk of heart disease have been given pills such as statins to reduce levels of cholesterol – the fatty substance that causes the plaques.

At-risk patients have also been given pills to lower blood pressure, which further reduces the risk of an attack. And when people start suffering severe symptoms a stent can be inserted to widen arteries and increase blood flow to the heart.

But Dr Ramzi Khamis, a consultant cardiologist and researcher at Imperial, said that by identifying and directly treating the most dangerous plaques – known as atherosclerosis – the most vulnerable patients could be saved.

“If you’ve got atherosclerosis in your arteries, one of a few things can happen,” he said. “The first is nothing – you could just live with it and carry on.

“The second thing is that it gets worse, worse and worse, and the blood supply becomes reduced to the heart muscle and you get something called angina. We fix that by giving medication but also by putting in stents.

“But the third thing is the most dangerous thing – the plaque ruptures, and you get a clot and that clot completely blocks the blood supply to the muscle, and you have a heart attack.”

He added: “Despite giving people medications, there’s still a big gap in identifying which plaques will rupture and therefore cause a heart attack, and which ones are stable and will just be there.”

Khamis and his colleagues in 2016 published a paper showing they could identify the most dangerous of those plaques by using an antibody that latched on to oxidised “LDL” cholesterol, the substance that is most likely to rupture. The antibody was marked with a fluorescent dye, allowing doctors to see it in scans.

The team has taken the technology a step further, so they can not only identify the most dangerous plaques but also treat them.

A microscopic nanoparticle – developed by Queen’s University Belfast – is loaded with anti-inflammatory drugs, attached to the antibody and injected into the bloodstream. The antibody latches on to the plaque, the nanoparticle gradually dissolves, releasing the medication, and the fragile parts of the blockage are harmlessly broken down, stabilising the plaque.

Dr Adam Hartley, a member of the team at Imperial, will this week present early findings – which are expected to show the treatment has been effective in breaking down plaques in mice – at the European Society of Cardiology congress in Barcelona.

Khamis said: “We are looking to move into human studies for imaging and therapeutics in the next three to five years.”

If those trials were successful, he expected the treatment to benefit those at highest risk – in particular people who had already survived a heart attack.

“Patients who have already had a heart attack or stroke have three times the risk of having another heart attack than the rest of the population.

“The future plan would be to use screening blood tests and risk factor assessment in patients that have already had a cardiovascular event, to screen for those who might benefit from this new technology.”

The treatment is likely to be given in the form of a subcutaneous injection, which can sometimes be given by a patient themselves into the layer of fat beneath the skin of the stomach or leg.

Professor Sir Nilesh Samani, medical director at the British Heart Foundation, which funded the research, said: “Despite the huge advances in treatment in recent decades, such as statins, we have not solved the problem of atherosclerosis and many people remain at high risk of heart attack and stroke.

“Targeting the build-up of dangerous cholesterol in plaques using antibodies provides an alternative way of tackling this risk.”

The Times