N Swanson

Primary percutaneous coronary intervention for acute ST-segment elevation myocardial infarction: changing patterns of vascular access, radial versus femoral artery

Objective: To examine the safety and efficacy of emergency transradial primary percutaneous coronary intervention for ST-elevation myocardial infarction. Design: Single-centre observational study with prospective data collection. Setting: A regional cardiac centre, United Kingdom. Patients: 1051 consecutive patients admitted with ST-elevation myocardial infarction, without cardiogenic shock, between November 2004 and October 2008. Interventions: Percutaneous coronary interventions by radial and femoral access Main outcome measures: The primary outcome measures were procedural success, major vascular complication and failed initial access strategy. Secondary outcomes were in-hospital mortality and major adverse cardiac and cerebrovascular events, needle-to-balloon times, contrast volume used, radiation dose absorbed and time to discharge. Multiple regression analysis was used to adjust for potential differences between the groups. Results: 571 patients underwent radial access and 480 femoral. A variable preference for radial access was observed among the lead operators (between 21% and 90%). Procedural success was similar between the radial and femoral groups, but major vascular complications were more frequent at the site of femoral access (0% radial versus 1.9% femoral, p = 0.001). Failure of the initial access strategy was more frequent in the radial group (7.7% versus 0.6%, p<0.001). Adjustment for other procedural and clinical predictors did not alter these findings. Needle-to-balloon time, as a measure of procedural efficiency, was equal for radial and femoral groups. Conclusions: In the setting of acute ST-elevation myocardial infarction without cardiogenic shock, transradial primary angioplasty is safe, with comparable outcomes to a femoral approach and a lower risk of vascular complications.

Long-term mortality after primary percutaneous coronary intervention for high-risk myocardial infarction.

BACKGROUND Primary percutaneous coronary intervention (PPCI) has evolved, including the introduction of stents and platelet glycoprotein IIb/IIIa receptor inhibitors (GPI). The effects of these changes and other variables on long-term survival for a single-centre service were studied. METHODS A prospective database of clinical and angiographic variables were kept for patients treated with PPCI in Waikato Hospital from 1996 to 2006 (n=527). This was analysed with long-term mortality data. Survival was recorded using Kaplan-Meier curves. Multivariate analysis of factors at presentation, including ethnicity was performed. RESULTS 5, 8 & 10-year survival rates were 76.5% (n=274), 72.7% (n=125) & 71.0% (n=19) respectively. Increased stent (42.8% vs. 84.1%, p<0.001) and GPI (39.6% vs. 73.3%, p<0.001) use was seen between early and late stages of the study. Stent use was associated with greater 5-year survival (80.5% vs. 70.8%, p=0.02), but GPI use was not. Multivariate analysis showed stent use independently predicted reduced mortality. Age, Maori ethnicity, renal failure and cardiogenic shock predicted higher mortality. CONCLUSIONS Survival after PPCI remains high long-term. Stent and GPI use significantly increased. Stent, but not GPI, use was associated with improved survival. Maori ethnicity was under-represented in the study and is associated with worse long-term outcomes after myocardial infarction (MI).

The SSTARS (STeroids and Stents Against Re-Stenosis) Trial: Different stent alloys and the use of peri-procedural oral corticosteroids to prevent in-segment restenosis after percutaneous coronary intervention

BACKGROUND Stent design and technological modifications to allow for anti-proliferative drug elution influence restenosis rates following percutaneous coronary intervention (PCI). We aimed to investigate whether peri-procedural administration of corticosteroids or the use of thinner strut cobalt alloy stents would reduce rates of binary angiographic restenosis (BAR) after PCI. METHODS This was a two centre, mixed single and double blinded, randomised controlled trial using a factorial design. We compared (a) the use of prednisolone to placebo, starting at least six hours pre-PCI and continued for 28days post-PCI, and (b) cobalt chromium (CoCr) to stainless steel (SS) alloy stents, in patients admitted for PCI. The primary end-point was BAR at six months. RESULTS 315 patients (359 lesions) were randomly assigned to either placebo (n=145) or prednisolone (n=170) and SS (n=160) or CoCr (n=160). The majority (58%) presented with an ACS, 11% had diabetes and 287 (91%) completed angiographic follow up. BAR occurred in 26 cases in the placebo group (19.7%) versus 31 cases in the prednisolone group (20.0%) respectively, p=1.00. For the comparison between SS and CoCr stents, BAR occurred in 32 patients (21.6%) versus 25 patients (18.0%) respectively, p=0.46. CONCLUSION Our study showed that treating patients with a moderately high dose of prednisolone for 28days following PCI with BMS did not reduce the incidence of BAR. In addition, we showed no significant reduction in 6month restenosis rates with stents composed of CoCr alloy compared to SS (http://www.isrctn.com/ISRCTN05886349).

1 Route of admission in stemi: do patients who present directly to a PCI-capable hospital differ from inter-hospital transfers?

Background Rapid delivery of reperfusion therapy with PPCI is the gold standard treatment in STEMI. Systems have been developed, such as direct admission to a PCI-capable hospital, to minimise the time from diagnosis to PPCI. Despite this, a significant minority of patients are initially admitted to non-PCI capable hospitals. The aim of this study was to determine whether patients differed in their characteristics, time to PPCI, and outcome by route of admission. Methods The study was performed in a single tertiary centre in North England. Data are collected routinely on all patients undergoing PPCI and include demographic, clinical and procedural variables. In-hospital MACCE (death, re-infarction or CVA) and mortality are collected providing relevant outcome measures. Baseline clinical variables by route of admission were compared and unadjusted in-hospital MACCE rates determined. One-year mortality by route of admission was calculated using the K-M product limit estimate. In-hospital and 1-year outcomes were analysed after adjustment for factors known to be predictors of early mortality following STEMI (models 1 and 3). To determine the relative importance of delays in treatment, call-to-balloon time was added (models 2 and 4). Logistic regression was used for the adjusted in-hospital outcomes, and Cox-proportional regression for adjusted 1-year mortality. Results 2268 patients were included in the analysis. 510 patients (22.5%) were treated with PPCI following transfer from a non-PCI capable centre. Analysis of baseline variables (Abstract 1 table 1) showed the transfer group were more likely to have an LAD occlusion treated, and previous MI. Despite shorter DTB times, the transfer group had a greater median CTB time (52 minutes longer) compared with direct admissions. Other baseline variables were statistically no different between groups. There were 110 in-hospital MACCE events, and 168 deaths within 1-year follow-up. The transfer group had significantly higher unadjusted in-hospital MACCE rates (2.4% absolute, 58% relative increase (Abstract 1 table 2)). At 1 year, the transfer group had significantly higher unadjusted mortality (2.7% absolute, 48% relative increase (Abstract 1 table 2)). After adjustment for relevant co-variates (models 1 and 3) route of admission remained a significant predictor of in-hospital and 1-year mortality. With the addition of call-to-balloon time, no significant difference in outcome was noted by route of admission for either in-hospital or 1-year events.Abstract 1 Table 1 Direct Transfer p Age (years±SD) 64.3 (12.7) 63.9 (12.4) 0.17 Male 1252 (71.2) 367 (72.0) 0.74 Diabetes 177 (10.1) 55 (10.8) 0.68 Previous MI 225 (12.6) 89 (17.3) 0.001 Treated vessel 0.001  LMS 24 (1.4) 13 (2.5)  LAD 630 (36.1) 218 (42.9)  LCx 249 (14.3) 83 (16.3)  RCA 812 (46.6) 188 (37.0)  Graft 28 (1.7) 5 (1.1) Cardiogenic shock 28 (1.7) 35 (6.9) 0.61 Smoking (ex/current) 1331 (75.7) 377 (73.9) 0.42 Call-to-balloon time 102 (82–135) 154 (107–235) <0.001 Door-to-balloon time 44 (29–76) 34 (24–50) <0.001Abstract 1 Table 2 Direct Transfer OR (±95% CI) p In-hospital MACCE 4.3% 6.7% 1.58 (1.04 to 2.39) 0.03 Adjusted in-hospital MACCE (model 1) 1.64 (1.00 to 2.28) 0.05 Adjusted in-hospital MACCE (model 2) 1.34 (0.79 to 2.29) 0.27 Direct Transfer HR (±95% CI) p 1-year mortality 7% 9.7% 1.48 (1.06 to 2.07) 0.02 Adjusted 1-year mortality (model 3) 1.41 (0.99 to 2.01) 0.05 Adjusted 1-year mortality (model 4) 1.29 (0.87 to 1.89) 0.20 Conclusion In this study, patients who presented directly had superior in-hospital and 1-year outcomes compared with those who required transfer from other hospitals. Adjustment for longer call-to-balloon times attenuated the finding of poorer outcomes in these patients, suggesting that delays in treatment are critical. Systems of care should be designed to avoid admission of STEMI patients to non-PCI hospitals, and facilitate more rapid transfer of patients where this has not been possible.

27 Use of rotational atherectomy in primary pci for st-elevation myocardial infarction- a single centre 10-year experience

Introduction Rotational atherectomy (RA) during primary PCI (PPCI) for STEMI is relatively contraindicated because of the perceived increased risk of no-reflow. However, RA PPCI may sometimes be required to restore flow in heavily calcified coronary arteries. Previously only very limited observational data has described the use of RA in PPCI. Aim We report the clinical and procedural characteristics, and in hospital outcomes, of 21 patients who underwent RA PPCI at our centre between 2006 and 2016, Methods A retrospective review of the PCI database and medical records. Results 21 patients (age 78(10) years (mean (SD)), 12 men) underwent RA during PPCI (0.4% of all PPCI). 3 patients had cardiogenic shock at presentation and 2 had out of hospital cardiac arrest. Hypertension (n=19), smoking history (n=18), hypercholesterolemia (n=16), diabetes (n=6) and chronic kidney disease (n=6 with eGFR<60) were frequently present. Aspirin was given to 20/21 patients and clopidogrel, ticagrelor and prasugrel to 10, 9 and 3 patients respectively. Heparin was used in all patients, glycoprotein (GP) IIBIIIA inhibitor in 10 and bivalirudin in 2. Radial access was used in 14 and femoral in 7. Initial TIMI flow grade was 0, 1, 2 and 3 in 11, 2, 1 and 7 patients respectively. The target vessel was the RCA in 14, Cx in 4, LMS in 2 and LAD in 1. All were severely calcified with visible thrombus in 13/21. The lesion length was 36(19) mm (range 12–72 mm). The vessel diameter was 2.5–2.99 mm in 5, 3–3.49 mm in 10 and 3.5–4.0 mm in 6. RA was used because of anticipated difficulty with conventional PCI in 7/21 and uncrossable/unexpandable lesions in 14/21. The number of burrs used was 1.33 (0.48) and the final burr was 1.25, 1.5, 1.75 and 2 mm in 4, 11, 4 and 1 patient respectively. The burr-to-artery ratio was <0.4 in 5 and 0.4–0.6 in 16. The final procedure was DES in 17, BMS in 3 and POBA followed by CABG in 1. A temporary pacemaker was used in 3 cases and intra-aortic balloon pump in 3 cases. There were no perforations, no tamponade and no vascular complications. The median(range) pain-to-PCI time was 180 min (114–544); door-to-PCI time 49 min (21–186, 14 patients <60 min) and procedure time was 119 min (66-175). Procedural difficulty caused door-to-PCI>60 min in 5/7 patients while medical/logistic reasons contributed in the other 2. 1 patient underwent CT scanning prior to PCI; 1 underwent an urgent MDT discussion before PCI. Final flow was TIMI 3 in 19/21 and TIMI 2 in 2/21 cases. The procedure was complicated by 1 event of distal embolization. There was 1 event of peri-procedural cerebral infarction. 20/21 patients survived to hospital discharge. Conclusions Our study suggests that RA PPCI can be performed safely in a small group of predominantly elderly, complex patients in whom conventional techniques are inadequate or unsuccessful. It is associated with a relatively long procedure time but we did not experience a marked increase in no-reflow.

97 Can pre-operative troponin levels predict post-operative mortality following non-cardiac surgery?

Introduction Despite advances in surgical and anaesthetic techniques, non-cardiac surgery still has a significant mortality. We hypothesised that pre-operative troponin levels might predict post-operative mortality. Methods Patients undergoing elective and urgent/emergency non-cardiac surgery excluding minor procedures were retrospectively assessed for known vascular disease (defined by diagnostic imaging or previous intervention rather than clinical assessment) and vascular risk factors including hypertension, treatment with lipid-modifying agents (irrespective of agent or dose) and chronic lung disease. Pre-operative high-sensitivity troponins and routine pre-operative bloods were recorded. Six- and twelve-month mortality data were collected; independent predictors of mortality and associations between pre-operative patient characteristics and pre-operative troponin were determined. Results 993 patients were assessed; 13% had an elevated pre-operative troponin with 3%>50 ng/L. 825 (83%) were elective patients; 8.6% had an elevated pre-operative troponin. Six-month mortality was 4.2% and 5.9% at twelve months. Elevated pre-operative troponin was associated with higher post-operative mortality; 2.5%, 12.5% and 25% for a troponin <17 ng/L, 17 – 49 ng/L and >50 ng/L respectively (figure?1). This trend was also evident at twelve months; 3.7%, 16.3% and 37% for the same troponin bands (figure 2). Lipid-modifying agents were independently associated with a lower rate of pre-operative troponin release (HR 0.446 (0.232 – 0.857) p=0.015). Impaired renal function (assessed as a continuous variable), emergency presentation and pre-operative troponin levels were independent predictors of six- and twelve-month mortality with emergency presentation the strongest predictor by hazard ratio (table 1). Age over 75 independently predicted twelve-month mortality only. Conclusion The role of pre-operative troponin monitoring and the prevalence of pre-operative troponin has not previously been established on an all-comer population. Pre-operative troponin level greater than 50 ng/L is an independent predictor of six and twelve-month mortality following non-cardiac surgery in an all-comers cohort although the mechanism of troponin release is not clear. The lower rate of troponin release associated with lipid-modifying medication has been seen in other studies (1). We hypothesise the known anti-inflammatory effects of statins may indicate a systemic inflammatory process responsible for the troponin release rather than unstable coronary disease. Further studies to assess this in the elective population may be useful to target pre-operative interventions. Reference Association between pre-operative statin use and major cardiovascular complications among patients undergoing non-cardiac surgery: the VISION study. ?Berwanger O, Le Manach Y, Suzumura EA, et al. Eur Heart J2016Jan 7;37(2):177?–?85Abstract 97 Table 1Abstract 97 Figure 1Abstract 97 Figure 2

88 Routine Post-Operative Troponin Screening for Myocardial Injury after Noncardiac Surgery (MINS) Events – A Single Centre Experience

Introduction The VISION study demonstrated an association between 30-day mortality after surgery and raised post-operative troponin levels.1 Subsequently, diagnostic criteria for ‘ischaemic’ MINS were established excluding non-ischaemic aetiology.2 We evaluated our initial experiences with post-operative troponin monitoring, to look in-depth at patients who suffer MINS events. Methods Pre- and post-operative high-sensitive troponins were checked on all elective and emergency surgical patients over 45 years of age with an inpatient stay of more than 2 days between August 2014 and June 2015. A MINS event was defined as in the VISION (1) study as any positive post-operative troponin. Thirty-day mortality after surgery was determined via HES data. Notes, pathology reports and discharge letters were reviewed for evidence of sepsis, prolonged tachycardia, multi-organ failure or significant bleeding (Hb loss of >5 g/l and/or total Hb <8 g/dl). Events were classified as ‘non MINS’, ‘unexplained MINS’ or ‘secondary MINS’ due to one of these provoking factors. Cox regression analysis was performed to assess association between variables. Results 388 patients were studied. 196 were male with a mean age of 69 years (range 45–95). 132 (34%) were emergency admissions. 245 (63.1%) had normal post-operative troponins (i.e. non MINS), with 81 (20.9%), 49 (12.6%) and 13 (3.4%) recording troponin levels of 17–50, 51–1000 and more than 1000 respectively. 21 of the positive post-op values represented a downward trend from pre-op tests, with a further 17 positive pre-op values falling into the normal range post-operatively.Abstract 88 Table 1 Types of MINS and 30 day mortality Pathophysiology Emergency N = 132 (% of total MINS) Elective N = 256 (% of total MINS) All surgery N = 388 (% of total MINS) 30 day mortality N = 11 (% of total mortality) All MINS events 82 60 142 8 (72.7%) Unexplained MINS 31 (37.8%) 39 (65%) 70 (49.3%) 0 (0%) Secondary to Sepsis 41 (50%) 15 (25%) 56 (39.4%) 8 (72.7%) Secondary to Bleeding 9 (11%) 5 (8.3%) 14 (9.9%) 0 (0%) Secondary to Tachycardia 1 (1.2%) 1 (1.7%) 2 (1.4%) 0 (0%) No MINS event 50 196 246 3 (27.3%) All patients 132 256 388 11 The 30 day mortality rate was 2.8% compared to 1.9% in VISION. Of the 11 deaths, 10 (90.9%) were emergency admissions. Two (18.2%) deaths occurred in patients exhibiting a downward trend in troponin and 3 (27.3%) had a normal post-operative troponin (i.e. did not suffer a MINS event). Discussion A raised post-operative troponin was associated with poor prognosis as suggested in the VISION study (p = 0.022 HR 0.213 [0.057–0.803]). Sepsis was also associated with a poor prognosis (p < 0.001 HR 0.08 [0.021–0.305]) as is emergency admission for surgery (p = 0.004 HR 0.05 [CI 0.006–0.392]). However, there was no mortality from ‘ischaemic’ MINS events (unexplained events and events secondary to tachycardia and bleeding). Whether MINS events are a separate clinical entity related to unstable or significant coronary disease or a reflection of other poor prognostic factors remains unclear. Further studies assessing coronary anatomy may be useful in delineating this further. References Devereaux PJ, Chan MT, Alonso-Coello P, et al. Association between Post-operative Troponin Levels and 30-Day Mortality among Patients undergoing Noncardiac Surgery. JAMA. 2012;307(21) Myocardial Injury After Noncardiac Surgery. VISION Study Investigators. Anaesthesiology, 2014;120: 564-–78

30 Do PRAMI and CVLPRIT represent real-life experiences of culprit-only PPCI? - a single centre observational study

Introduction The RCTs, PRAMI1 and CVLPRIT,2 have suggested that preventative PCI for multi-vessel disease identified during PPCI improves outcomes with higher rates of cardiovascular events in the culprit-only cohorts. Methods 1143 consecutive STEMIs at our centre from August 2011–2013 were retrospectively assessed for eligibility to one or both trials. 343 patients would have been suitable for PRAMI and 196 for CVLPRIT; termed ‘observational’ cohorts. Outcomes were determined from clinic letters, procedure reports and regional blood result reporting with mortality outcomes compared to ONS data. Results Over 36 months, our observational PRAMI cohort experienced fewer combined primary outcomes (13.9% vs 22.9%), comparable to the preventative PRAMI (Figure 1A) arm with only 8.5% undergoing additional early planned revascularisation. Our observational CVLPRIT cohort experienced numerically fewer MACE primary outcomes over 12 months (16.8% vs 21.2% Figure 1B) with 30 day event rates comparable to the preventative PCI cohort, despite only 9.2% undergoing additional early planned revascularisation. Abstract 30 Figure 1 A – Primary outcomes from PRAMI (1) cohorts, B – Primary outcomes from CVLPRIT (2) cohorts. Original graphs reproduced with permission with observational cohort outcomes superimposed Conclusion Our all-comers culprit-only PCI cohorts have better outcomes than those seen in the published RCTs suggesting a high-risk population may have been selected for inclusion. Reference PRAMI trial. Wald DS, Morris JK, Wald NJ, et al. Randomized trial of preventive angioplasty in myocardial infarction. N Eng J Med. 2013, 369(12), 1115–1123 CVLPRIT trial. Gershlick AH. Khan JN, Kelly DJ, et al. Randomized trial of complete versus lesion-only revascularization in patients undergoing primary percutaneous coronary intervention for STEMI and multivessel disease: the CvLPRIT trial. J Am Coll Cardiol. 2015 Mar 17;65(10):963–972. Figure A was originally published in N Eng J Med, 369(12):1115–1123, D. S. Wald et al, Randomised Trial of Preventive Angioplasty in Myocardial Infarction, Copyright

65 Proximal Lad PCI - Single Centre Long Term Outcomes 2003–2013

The 2010 ESC guidelines on myocardial revascularisation state that for patients with significant disease in the proximal LAD (pLAD), CABG is the preferred revascularisation strategy (class I, evidence Level A) and that PCI is less strongly supported (class IIa, evidence level B). The 2011 ACC/AHA guideline for PCI does not differentiate between modes of revascularisation for pLAD disease. We have analysed all PCI procedures performed at this institution between January 2003 and January 2013 with reference to involvement of the pLAD and long term outcome. In total 14,935 PCI procedures were undertaken. We excluded 4,080 emergency PCIs for STEMI. We present data for 10,855 PCIs, 6,859 for ACS patients and 3,996 for patients with stable angina. Of these, 2,723 (25%) involved the pLAD and 8,132 (75%) non-pLAD disease (non-pLAD). Median follow up was 5.9 years, with 5 year follow up available for 6,387. Patients with pLAD versus non-pLAD PCI were of similar age (median age 62 (IQR 54–72) vs 63 (IQR 56–71)) but more likely to be male (73% vs 71%, p = 0.04). pLAD patients were less likely to have had previous MI (22.5% vs 29.3%, p < 0.001), previous PCI (13.3% vs 18.6%, p < 0.001) or previous CABG (1.5% vs 11.2%, p < 0.001). Patients with pLAD disease were more likely to undergo multi vessel PCI (30.6% vs 16.1%, p < 0.001) or present with shock (0.8% vs 0.5%, p = 0.03). Use of DES was greater in the pLAD PCI group (77.8% vs. 66.8%, p < 0.001). Mortality rates at 1 and 5 years are shown in Table 1. The data for repeat revascularisation are shown in Table 2 and are derived from data on patients returning to this hospital and do not include patients who may have attended a different cardiothoracic centre. Local geography means that this should be a small number. Abstract 65 Table 1 Mortality 1 year 5 years pLAD 2.6% 9.9% non-pLAD 2.2% 12.0% p value 0.26 0.02 Abstract 65 Table 2 Repeat revascularisation at any time PCI (any) PCI (target lesion) CABG pLAD (n = 2723) 10.9% 5.1% 2.3% non-pLAD (n = 8132) 14.2% 6.9% 2.7% p value <0.001 0.001 0.24 Conclusion Our data suggest that the long term results for PCI to the pLAD are at least as good as the results for non-pLAD PCI. The rates of repeat revascularisation by PCI or CABG are markedly lower than in studies cited in the 2010 ESC revascularisation guideline which were mainly based on PCI by balloon angioplasty. The ESC guidelines are not based on contemporary outcomes of PCI for pLAD disease.

029 Management and outcomes of patients following out-of-hospital cardiac arrest

Introduction Treatment of patients with out-of-hospital arrest (OOHA) is complex, may be time sensitive and depends on the coordinated actions of diverse healthcare providers. There are no clear guidelines for the management of these patients and there is a lack of outcome data for those presenting with cardiac causes. We reviewed the characteristics and outcomes of a series of patients with OOHA referred and accepted to a tertiary cardiac service. Methods and Result Between January 2010 and October 2011, 76 pts with OOHA were accepted by our unit. Median age was 62 years (21–91) and 66% were male. The diagnosis of STEMI was made prior to the arrest in 38 pts (Gp 1) and emergency angiography ± PCI was attempted. PCI was done in 36 (95%). 14 (37%) were in cardiogenic shock, 9 (24%) were transferred to ITU, 5 (13.2%) had therapeutic cooling and 33 (87%) survived to hospital discharge. In 20 pts, the diagnosis of STEMI was made following resuscitation (Gp 2). Of these 18 (90%) had angiography + PCI, 9 (45%) were in cardiogenic shock, 6 (30%) had therapeutic cooling, 12 (60%) admitted to ITU, 3 (15%) were admitted to ITU first before coming to the Cath lab and 15 (75%) survived to discharge. There was no evidence of STEMI following resuscitation in 18 pts accepted by our unit (Gp 3). Of these, 17 (94%) had angiography, 7 (39%) had PCI, 2 (18%) had CABG, 2 (18%) were in cardiogenic shock, 15 (83%) were admitted to ITU, 7 (38%) had therapeutic cooling and survival to discharge was 94%. In Gp 3, angiography was delayed pending a head CT in 7 (38%) compared to none in Gps 1 and 2. Angiography was deferred following initial ITU treatment in 8 (44%) patients in Gp 3. Overall survival in patients with and without cardiogenic shock was 58% and 98% respectively (p<0.01). Survival was 87% for those with a witnessed OOHA compared to 40% where the arrest was not witnessed (p<0.05). Conclusion A programme of immediate cardiovascular assessment of patients with OOHA and referral for angiography and revascularisation as deemed appropriate is associated with encouraging short-term outcomes. Outcomes are related to the presence of shock and whether the OOHA was witnessed or not. National guidance on the immediate management of these patients may improve outcomes.