Specialists at the Golden Jubilee National Hospital have shown that in ‘high risk’ heart attack patients, after blood flow has been restored in the blocked artery, delaying putting a stent could aid their recovery, according to research published in the Journal of the American College of Cardiology.
The usual procedure for patients who have suffered a ST segment elevation myocardial infarction (STEMI) – the most serious type of heart attack – and who are at risk of ‘no reflow’ is to immediately insert a stent after blood flow has been restored.
A STEMI heart attack occurs when the coronary artery is totally blocked resulting in prolonged interruption to the blood supply if not treated promptly. Placing a stent helps keep the artery open but the stent can also cause harmful ‘no reflow’.
‘No-reflow’ is a phenomenon where, although blood flow through the blocked artery is restored, blood still cannot return to the oxygen-starved area of the heart. This is because the tiny vessels within the damaged muscle do not allow blood to flow. About 40 per cent of people who have had a STEMI heart attack are at increased risk of ‘no reflow’.
The study, funded by the British Heart Foundation (BHF) and the Chief Scientist Office of Scotland, involved 101 patients at high risk of ‘no reflow’ after experiencing a STEMI heart attack.
The researchers from the Golden Jubilee National Hospital and the University of Glasgow assessed a new and entirely different approach for heart attack treatment. This was where doctors inserted a stent straight away in one group of patients, which is usual standard care, whilst stenting was delayed by between four and 16 hours in the other group.
All patients were monitored for at least six months after discharge. The results concluded that waiting for a period of time before putting in a stent in higher-risk heart attack patients reduces the likelihood of ‘no-reflow’ and may improve clinical outcome.
Professor Colin Berry of the Golden Jubilee National Hospital and Institute of Cardiovascular and Medical Sciences at the University of Glasgow, said: “For the first time, we have shown that deferred stenting in patients having a STEMI heart attack reduced no-reflow and decreased the size of the heart attack compared to conventional treatment with immediate stenting.
“We think that deferred stenting allows any residual clot in the artery causing the heart attack to break-up. In certain cases, if a stent is placed immediately some of this clot material can be dislodged and cause further damage to the heart muscle. When the stent placement is deferred for a few hours, the final results are better with overall less damage to the heart muscle.”
Professor Jeremy Pearson, Associate Medical Director at the BHF, said: “This innovative study suggests that patients who have had a major heart attack have a better outcome if surgeons wait several hours before putting in a stent.
“If researchers confirm these findings in larger trials we could see a major change in how patients who have had a heart attack are treated.”
Professor Keith Oldroyd, Consultant Cardiologist and Director of Research at the Golden Jubilee, added: “This strategy is simple, pragmatic and potentially widely applicable, but a large multicentre clinical trial in the NHS will be needed to fully assess its risks, benefits and cost-effectiveness. And as with any research, we want to ensure that positive findings lead to changes in clinical practice, which in turn will significantly benefit how we care for our patients”
Since its creation five years ago, the Golden Jubilee has established itself as one of the UK’s leading ‘heart attack centres’. The concentration of resources, skills and expertise within the centre has enabled this state of the art national hospital to lead the way in research, development and academic activity which ensures innovation and improvements in patient care.
A Randomized Trial of Deferred Stenting versus Immediate Stenting to Prevent No-or Slow Reflow in Acute ST-Elevation Myocardial Infarction (DEFER-STEMI), David Carrick, Dr; Keith G. Oldroyd, Professor; Margaret McEntegart, Dr; Caroline Haig, Dr; Mark C. Petrie, Dr; Hany Eteiba, Dr1; Stuart Hood, Dr; Colum Owens, Dr; Stuart Watkins, Dr; Jamie Layland, Dr; Mitchell Lindsay, Dr1; Eileen Peat, Dr; Alan Rae, Dr; Miles Behan, Dr; Arvind Sood, Dr; W. Stewart Hillis, Professor1; Ify Mordi, Dr; Ahmed Mahrous, Dr; Nadeem Ahmed, Dr; Rebekah Wilson, Ms; Laura Lasalle, Ms; Philippe Généreux, Dr; Ian Ford, Professor; Colin Berry, Professor.,J Am Coll Cardiol. 2014;():. doi:10.1016/j.jacc.2014.02.530, published 27 March 2014.