DEFER STEMI - A new approach to heart attack treatment
Issued: Thu, 23 May 2013 16:49:00 BST
A Randomized Trial of Deferred Stenting versus Immediate Stenting to Prevent No-Reflow in Acute ST-Elevation Myocardial Infarction
Authors: 1,2David Carrick MRCP; 2Margaret McEntegart MRCP, 3Caroline Haig MSc, 1Mark C. Petrie MRCP, 1Hany Eteiba FRCP, 1Stuart Hood FRCP, 1Colum Owens MRCP, 1Stuart Watkins MRCP, 1Mitchell Lindsay MRCP, 1Eileen Peat MRCP, 2Alan Rae FRCP, 1,2Jamie Layland MRCP, 4Miles Behan FRCP, 5Arvind Sood MRCP, 1W. Stewart Hillis FRCP, 1,2Ify Mordi MRCP, 2Ahmed Mahrous MSc, 1Nadeem Ahmed BMedSci, 1Rebekah Wilson, 6Laura Lasalle MPH, 6Philippe Généreux MD, 3Ian Ford PhD, 1Keith G. Oldroyd FRCP, 1,2Colin Berry FRCP.
Institutions: 1 BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow; 2West of Scotland Heart and Lung Centre, Golden Jubilee National Hospital; 3Robertson Centre for Biostatistics, University of Glasgow; 4Royal Infirmary of Edinburgh; 5Hairmyres Hospital, Lanarkshire; 6Cardiovascular Research Foundation and Columbia University Medical Center, New York City.
Heart attack is caused by the sudden blockage of a coronary artery due to a blood clot. This life-threatening condition, known as ST-elevation myocardial infarction (STEMI), is treated by opening the blocked artery with a catheter and then placing a stent. However, once the coronary artery is open, placing a stent can dislodge the blood clot and coronary flow may suddenly reduce or cease. This problem, known as ‘no-reflow’, causes heart failure and even death (Figure 1).
In this study, we assessed whether deferred stenting for a few hours might prevent no-reflow and improve treatment outcomes. In the DEFER-STEMI trial, Professor Berry and colleagues undertook a prospective randomised controlled proof-of-concept trial in acute STEMI patients in the Golden Jubilee National Hospital (Glasgow, UK). Patients with one or more risk factors for no-reflow were eligible if normal blood flow was initially established after re-opening the blocked artery. Randomisation was to deferred stenting with an intention-to-stent 4-16 hours later or conventional treatment with immediate stenting. This time window was chosen to permit sufficient time for the beneficial effects of reperfusion (i.e. at least 4 hours) while temporising the length of time that a patient might wait for the second procedure (i.e. maximum 16 hours). The primary outcome was the occurrence of no/slow-reflow based on independent analysis of the coronary angiograms blind to treatment allocation. These analyses were carried out by the Cardiovascular Research Foundation Angiographic Core Laboratory in New York, USA. DEFER STEMI was publically registered as a clinical trial (NCT01717573).
Between 11th March 2012 - 21st Nov 2012, 411 STEMI patients were treated in the Golden Jubilee National Hospital. All of these patients were entered in a registry. Of these, 101 patients (mean age 60 years, 69% male) with eligibility criteria were randomised (n=52 deferred group, n=49 immediate stenting). The clinical characteristics in both groups were similar. The median (IQR) time to the second procedure in the deferred group was 9 (6, 12) hours. Compared with immediate stenting, fewer patients in the deferred group had no/slow-reflow or intra-procedural thrombotic complications (Figure 2) and blood flow in the culprit coronary artery at the end of the procedure was better in the deferred group than in the immediately stented group (p=0.02). Two patients in the deferred group had a recurrent STEMI (< 6h). These patients promptly received a stent and had uncomplicated progress. In conclusion, deferred stenting in STEMI patients with clinical risk factors for no-reflow improved culprit artery blood flow and reduced complications during primary PCI. This new approach to heart attack treatment is simple, pragmatic and potentially widely applicable.
Our study was supported by the British Heart Foundation and NHS Scotland.
DEFER STEMI was presented at a Featured Research Session on March 9th, 2013 at the American College of Cardiology Annual Scientific Sessions.
Published 23rd May 2013
Correspondence: Professor Colin Berry, BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, 126 University Place, University of Glasgow, Glasgow, G12 8TA, Scotland, UK. Telephone: +44 (0) 141 330 1671 or +44 (0) 141 951 5000. Fax +44 (0) 141 330 6794 Email: email@example.com