Introduction: The profile of cardiovascular risk factors (RF) have been changing in our community with recent reports suggesting they are also changing among patients with myocardial infarction (MI). We sought to examine the RF profile of our ST-elevation MI (STEMI) population and whether the RF profile of STEMI patients have changed over time. Methods: We performed a retrospective analysis of patients from the Westmead Hospital STEMI database, which includes consecutive patients presenting with STEMI between January 2006 to December 2017. We examined the prevalence of five key RF and prevalence of the number of these RF. The RFs were hypertension, hypercholesterolaemia, diabetes, smoking and family history of ischaemic heart disease (IHD) at age <60 yr. Results: Of the 3256 STEMI patients during the 12-year period, 20.5% were female, average age 61years, 52% of patients had hypertension, 52% had hypercholesterolaemia, 29% diabetes, 61% smokers and 37% reported a family history of IHD. Over the 12 years, patients with no RFs rose from 3 to 13.6% and there was a reduction from 21 to 11% in patients with a total of >4 RFs. The trends were similar for younger (<60 years of age) versus older patients, patients with and without a history of IHD, and gender. Conclusion: This study confirms an increasing proportion of patients with fewer risk factors for STEMI over time. This may help identify patient populations in which novel mechanisms may contribute to the aetiology of their STEMI and allow further research into targeted secondary prevention.

Background: Cardiac arrest has been associated with poor outcomes in patients presenting for primary percutaneous coronary intervention (PPCI). Mechanical compression devices such as the Lund University Cardiopulmonary Assist System (LUCAS-3) aim to reduce ischaemic time during cardiopulmonary resuscitation. Methods: We conducted a retrospective review of consecutive patients with ST-elevation myocardial infarction or suspected severe myocardial ischaemia undergoing PPCI at a large tertiary institution between January 2017–December 2018. The study group comprised patients with an out-of-hospital cardiac arrest (OOHCA), in-hospital cardiac arrest (IHCA), or both. Demographic data, downtime (defined as the time from recognised arrest to return of spontaneous circulation (ROSC)), use of the LUCAS-3, and survival to discharge, were collected. Results: Of 630 patients, 80 (12.7%) were identified as either OOHCA, IHCA, or both; of whom 75 (93.4%) achieved ROSC prior to attempt at PPCI. 7 patients had an on-table IHCA during angiography without obtaining ROSC. 55 patients (68.8%) were discharged alive. Comparison of baseline demographics between survival to discharge and fatality: Age: 59.8 vs 65.7 years (p = 0.018), median downtime 4 vs 32 minutes (p < 0.001), gender was not significant (p = 0.32). ROSC was achieved in all vs 52% (p < 0.001) respectively. LUCAS-3 was used in 16 patients, of whom 3 were discharged alive and had achieved ROSC prior to attempt at PPCI. Conclusions: Younger age, shorter downtime, and ROSC predict survival to discharge in patients with OOHCA, IHCA, or both who present for PPCI. LUCAS-3 did not show utility in our cohort in the absence of ROSC prior to PPCI.

Background: We assessed the cycle length (CL) of ventricular tachycardia (VT) induced at electrophysiology study (EPS) early post-MI with spontaneous VT at follow up in implantable-cardioverter defibrillator (ICD) recipients. Methods: Consecutive STEMI patients with left ventricular ejection fraction (LVEF) ≤40% underwent EPS as part of a study protocol targeting early (within 40 days) prevention of sudden cardiac death (SCD). The CL of induced VT at EPS was compared with first spontaneous VT and subsequent VT in ICD recipients at follow up. Secondary endpoints included mortality, sudden cardiac death (SCD) and cardiac arrest. Results: EPS performed early post-MI in 403 patients was negative in 68.5% (n = 276) and positive in 31.5% (n = 127). In patients with a positive EPS, induced monomorphic VT had mean CL 229 ± 29 milliseconds. Primary prevention ICD was implanted in 120/127 patients with a positive EPS. In EPS positive patients with an ICD, 33% had an appropriate activation due to either VF (n = 5) or VT (n = 35) mean CL 308 ± 47 milliseconds at mean 3.4 ± 2.7 years post-STEMI. In individual patients the induced VT CL at EPS did not correlate with first spontaneous VT CL (r = 0.09, p = 0.60) but instead the VT CL lengthened with time post-MI (r = 0.481, p < 0.001). Total mortality occurred in 15.7% and 5.1% of EPS positive and negative patients, respectively (p = 0.001). Conclusions: In patients post-MI with LVEF ≤40% and inducible VT at early EPS, the first episode of spontaneous VT at follow up in ICD recipients was significantly slower to what was induced. This is potentially related to the myocardial remodelling process post-MI.

Background: Risk stratification of patients who have had a ST elevation myocardial infarction (STEMI) remains controversial. The safety of programmed ventricular stimulation (PVS) in the acute phase after STEMI remains unclear.

Background: There is little known about the influence of BMI on ventricular arrhythmias in patients with ischaemic heart disease. Aim: The aim of our study was to assess the effect of BMI on the combined primary outcome of spontaneously occurring ventricular arrhythmias and mortality and the individual secondary outcomes of mortality and spontaneous ventricular arrhythmias in patients with STEMI, LV-dysfunction and ICD implantation. Methods: 123 consecutive patients with LV ejection fraction ≤ 40% after STEMI and who underwent ICD insertion either for primary or secondary prevention were included. Patients were classified as normal (43.9%), overweight (35%) or obese (20.3%). Results: The primary outcome occurred in 36% of the patients with normal weight which was more than those who were overweight and obese (5.4% and 11.5% respectively, p-0.001). Kaplan–Meier curves and the log-rank test revealed that overweight and obese patients had significantly lower incidence of death and ventricular arrhythmias (p < 0.01) in comparison to normal weight individuals. Using a Cox regression multivariable analysis when adjusting for ejection fraction, age and triple vessel disease, normal BMI remained a significant predictor for the primary outcome. Mortality was higher in normal weight patients (10%) compared to overweight (5.3%) and obese (3.8%) patients. Overweight and obese patients demonstrated a non-significant trend towards reduced survival in patients with normal weight (p = 0.346). Conclusion: In patients with post-MI LV dysfunction and ICD insertion, BMI remained a significant predictor for the combined primary outcome of spontaneously occurring ventricular arrhythmias and mortality. Our findings are consistent with the obesity paradox.

Background and objectives: Drug eluting stents (DES), compared with bare metal stents (BMS) in STEMI, have been shown to reduce the rate of in-stent restenosis (ISR) without a mortality reduction. DES is associated with increased risk of late stent thrombosis and is also considerably more expensive. This study assessed the long-term outcomes of DES use in selected patients at high risk of ISR. Methods: Consecutive patients (n = 1832) presenting with STEMI between April 2004 and January 2012 were included and grouped into two cohorts based on pre-specified criteria: high risk for in-stent restenosis who received DES (46%, n = 847), and low risk who received BMS (54%, n = 985). The lesion characteristics for the high-risk group were: target vessel ≤2.5 mm in diameter in non-diabetic patients and ≤3.0 mm in diabetic patients; lesion length >18mm; previous ISR; saphenous vein graft lesions; ostial lesions; bifurcation lesions; left main coronary artery lesions; and multi-vessel disease. Results: Patients were followed up for a median period of 24 months (inter-quartile range 6–35 months). At 24 months, there was no significant difference (DES vs BMS) in MACE (10.1% vs 14.9%, p = 0.070), mortality (7.6% vs 10.4%, p = 0.327), definite stent thrombosis (2.2% vs 1.6%, p = 0.094), TVR (6.3% vs 8.4%, p = 0.140) and TLR (5.1% vs 6.4%, p = 0.321). Patients who received DES had a lower rate of clinical ISR (2.3% vs 4.7%, p = 0.016). Conclusion: Selective use of DES in STEMI provides satisfactory long-term outcomes while limiting the number of patients exposed to DES costs.

Objectives: We performed serial Doppler echocardiography in patients with ST‐elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) to describe the temporal changes in Doppler parameters following STEMI. Background: Data on comprehensive Doppler assessment of diastolic dysfunction following STEMI, incorporating tissue Doppler imaging (TDI), are lacking. Severe diastolic dysfunction in stable patients usually manifests as a restrictive mitral filling pattern (RFP), reduced TDI‐derived annular velocities (E'), and elevated E/E' ratios >15. Methods: Twenty‐eight patients (19 males, mean age 60 ± 10 years) with a first‐ever STEMI who underwent PCI were prospectively assessed with echocardiography and invasive left ventricular end‐diastolic pressure (LVEDP) measurements prior to PCI. Repeat echocardiograms were performed at day 3 and 12 months. Results: During STEMI: (i) LVEDP was significantly elevated but decreased post revascularization (26.1 ± 6.2 vs. 20.8 ± 5.2 mmHg, P = 0.002); (ii) the predominant mitral inflow pattern was an abnormal relaxation pattern (n = 14 [50%]), whereas restrictive filling pattern was only observed in seven (25%) patients; (iii) E' velocities were only modestly reduced (septal E' 7.4 ± 2.2 cm/sec, lateral E' 9.6 ± 2.2 cm/sec), and (iv) a septal E/E'ratio >15 seen in only one patient, whereas all other patients had an E/E' ratio of 8–15. Serial TDI showed that E'velocity decreased at day 3 (septal E' 7.4 ± 2.1 cm/sec vs. 5.9 ± 1.6 cm/sec, P = 0.002) and remained reduced at 1 year follow‐up, suggesting persistence of diastolic dysfunction. Conclusions: During STEMI, contrary to findings in stable patients, the predominant Doppler manifestation of the severe diastolic dysfunction and elevated LVEDP was an abnormal relaxation mitral inflow pattern accompanied by E/E' ratios of 8–15. Serial Doppler assessment suggests incomplete diastolic recovery following STEMI.

Introduction: Variation in Electrophysiology study (EPS) inducibility protocol may account for differences in its predictive value for sudden cardiac death (SCD. Ventricular tachycardia (VT) induced with four ventricular extrastimuli (ES) was previously believed to be of non-specific prognostic value. We evaluated the long term prognosis of patients with VT induced with 1–4 ES post-ST elevation myocardial infarction (STEMI). Methods: Consecutive patients post STEMI (n = 142) with a left ventricular ejection fraction (LVEF) ≤ 40% underwent EPS. Monomorphic VT CL ≥ 200 ms induced by ≤4 ES was considered inducible. Patients were divided into VT induced with ≤2 ES (n = 37), 3 ES (n = 64) or 4 ES (n = 41). Primary endpoint was ventricular arrhythmia free survival; a composite of SCD, spontaneous ventricular arrhythmia or defibrillator-treated ventricular arrhythmia. Results: Mean age was 60 ± 12 years with mean LVEF 30 ± 6%. EPS was performed at a median of 12 days post-STEMI. An ICD for primary prevention was inserted in 83.8%, 73.4% and 56.1% of patients with inducible VT with ≤2, 3 or 4 ES, respectively (P = .005). At mean follow up of 50 ± 31 months, the ventricular arrhythmia free survival was 72.3 ± 8%, 64.3 ± 7% and 84.8 ± 6% in patients with inducible VT with ≤2, 3 and 4 ES respectively (adjusted hazard ratio of .76, 95% confidence interval .3–1.95, P = .57 for the 4 ES vs. ≤2 ES groups). Conclusions: The prognostic significance of VT induced by 4 ES is similar to that of VT induced by ≤2 or 3 ES in patients with STEMI and LVEF ≤40%. Limiting to 3 ES would have resulted in 22% of all arrhythmic events occurring in patients classified as non-inducible. The use of a fourth ES may increase the prognostic value of EPS in primary prevention of SCD.

South Asian migrants are rapidly increasing in particular in western Sydney and known to have a high prevalence of coronary artery disease (CAD). We compared outcomes of South Asian born patients with Australian born patients that had presented with an ST elevation myocardial infarction (STEMI) to a large tertiary hospital within Western Sydney. Data was retrospectively collected between January 2004 and January 2010 from the STEMI registry. A total of 973 consecutive patients were included; 864 (age 59 ± 13, 77.2% male) were Australian born and 109 (age 59 ± 14, 83.5% male) were South Asian born. Lipid profile, family history of CAD, and hypertension were not different between the groups. Diabetes was more common in the South Asian born group (37.2% vs 21.1%, P = 0.003), while smoking was more common in the Australian born group (71% vs 47.7%, P < 0.001). There was no significant difference in the mode of transport to hospital. There was a difference (P = 0.028) in emergency department triage criteria with more South Asian born patients triaged >2 (2.7% vs 1.6%) and less triage bypassed (16.2% vs 28%). Door to balloon time was however no different. Symptom to door time was significantly longer with South Asian born patients (202 ± 22 min vs 149 ± 7 min, P = 0.009). This translated to a non-significantly greater 30-day mortality in South Asian born patients (10% vs 6.3%, P = 0.2). In summary, South Asian migrants tend to delay initial contact with health care providers and were assessed and triaged differently. Therefore, specific guided strategies are needed to target this population.

Background: ICDs are an important treatment option in the management of arrhythmias post myocardial infarction. One complication of having an ICD is tricuspid regurgitation (TR), attributed to the passage of the transvenous lead across the tricuspid valve (TV). There is conflicting evidence regarding the effect of the ventricular lead on the TV with some evidence suggesting that the function is significantly compromised. Aim: To examine the impact of ICD leads on the TV by assessing the severity of TR in both acute (<6 months) and chronic (>12 months) phases after insertion. Methods: A retrospective review of patients who underwent percutaneous coronary intervention for an acute STEMI in a tertiary referral teaching hospital (2004–10), with left ventricular ejection fraction <40% at day 3 post infarct as determined by a gated heart pool scan or transthoracic echocardiography (TTE). Of the 299, 59 had an ICD inserted following detection of spontaneous or induced ventricular tachycardia on electrophysiological study within seven days of the infarct vs 241 who did not have ICD. Only subjects who had a TTE pre- and post-implantation of AICD TTE were considered. Results: In the case group 19 had TTEs at all three time points, 24 had TTES pre implant and within six months and the remaining 29 had echos pre implant and >12 months after implantation. The odds ratio of worsening TR at long term follow up compared to short term follow up was 1.6 (95% CI 0.7–3.6, p = 0.28 NS). Conclusion: The presence of an ICD does not appear to worsen tricuspid regurgitation with an odds ratio of 1.6 which was not statistically significant.

Background: The duration of ischaemia is an important determinant of survival following acute myocardial infarction (AMI). The impact of the duration of ischaemia on left ventricular (LV) diastolic properties following AMI has not been previously studied. We determined the correlation between the symptom-to-reperfusion time and severe diastolic dysfunction (restrictive filling pattern-RFP) in patients undergoing primary angioplasty (PAMI) for AMI.

Objective: To evaluate the best predictive model of 30-day mortality in patients presenting with a STEMI to the catheterisation laboratory of a tertiary teaching hospital in Western Sydney.

Background: Western Sydney has a unique multicultural mix (over 250 ethnic groups) with a significant proportion of residents being first generation migrants. The outcomes of multiple ethnic groups receiving identical STEMI management at a single centre have not been previously reported.

Aims: Historically, ST segment resolution (STR) assessed at ninety minutes post initiation of thrombolysis is a predictor of reperfusion success and cardiovascular outcomes in ST segment elevation myocardial infarction (STEMI). Our aim was to assess whether STR measured immediately post primary percutaneous intervention was (PPCI) was a useful predictor of adverse cardiovascular events.

Background: Field triaging of ST-elevation myocardial infarction (STEMI) has enabled shorter delays to reperfusion. The predictive role of ST-segment resolution at 90-min post-angioplasty in these patients is not known and is examined in this study.

Background: The Emergency Triage of Acute Myocardial Infarction (ETAMI) study investigated the use of field triage to expedite revascularisation by bypassing district hospitals (DH) and the regional heart centre (RHC) emergency department.

Background: PPCI is the treatment of choice for Acute Myocardial Infarction (AMI). With the need for assessing patients rapidly there is room for error in the diagnosis.