Jab to stop damage after a heart attack

AJaB that starts working in minutes could repair damage done by a heart attack and prevent risk of future heart failure. every year, some 270,000 people in Britain have a heart attack, typically when blood flow to the heart is reduced by a clot. This lack of oxygen-rich blood leads to the death of heart tissue.

The jab contains a protein, called insulin-like growth factor 1, that has been found to halt the damage and stimulate the growth of healthy new heart muscle.

researchers at university College Cork ran a trial involving 47 heart attack survivors and found less scar tissue — areas where heart muscle has ‘died’ — formed in those given the jab compared with those given a dummy treatment.

Tests found it starts working within half an hour. The one- off injection must be given within 12 hours of an attack. This is when the heart becomes floppy and unable to pump blood properly round the body.

Damaged by the lack of oxygen, heart muscle can undergo adverse remodelling — it changes shape. it can quickly become thin, reducing the heart’s ability to contract. This can lead to heart failure.

Drugs such as beta blockers and ace inhibitors can preserve heart function, but around 40 per cent of those with heart failure still die within a year of their first hospital admission. The jab may halt damage before heart failure occurs.

insulin–like growth factor 1 (igF-1) aids growth. released in high quantities during childhood, synthetic versions are sometimes used to treat dwarfism and conditions such as muscular dystrophy.

The jab was tested on patients left with severely reduced ejection fraction — a measure of how much blood the heart pumps out with each contraction.

Between two and 12 hours after their heart attacks, 16 patients had a low dose of 1.5 nanograms of igF-1 injected into the heart via a catheter fed through from an artery in the wrist.

another 16 received a dose of 15 nanograms. The other 15 had a dummy drug. Those on the high dose of igF-1 saw the biggest increase in diastolic volume, which suggests the heart is pumping blood more efficiently.

mri scans showed lower rates of scarring in those who got 15 nanograms of igF-1 than those on the smaller dose or placebo.

The results were presented at the recent european Society of Cardiology conference in Paris.

Noel Caplice, a professor of cardiovascular sciences at university College Cork, who led the study, said: ‘When igF-1 gets in the heart it stimulates receptors on cardiac cells. Within about 30 minutes, it sends a survival signal to the heart muscle cells.’

He said if larger planned studies show similar benefit, the jab could be available within five years.

Professor Stephen Westaby, a heart surgeon at John radcliffe Hospital, oxford, said the jab is ‘an interesting approach and moving in the right direction’.

MEANWHILE scientists are working on a one- off injection that may permanently lower raised cholesterol. it is designed to switch off a gene, PCSK9.

Those born with the gene switched off have naturally lower cholesterol. This is because the gene encourages production of a protein that helps block removal of harmful lDl cholesterol from the blood. The jab, being developed by astra Zeneca, has been successfully tested in animals.