Cardiogenic Shock Prior to Percutaneous Coronary Intervention in ST-Elevation Myocardial Infarction: Outcomes and Predictors of Mortality (ANZACS-QI 73).

BACKGROUND & AIMS: Cardiogenic shock (CS) is a serious complication of acute myocardial infarction (MI) and is associated with significant mortality. We describe a contemporary, real-world cohort of patients with ST-elevation MI (STEMI) and CS, including 30-day mortality and clinically relevant predictors of mortality. METHODS: All patients presenting with STEMI who were treated with percutaneous coronary intervention (PCI) in New Zealand (2016 to 2020) were identified from the Aotearoa New Zealand All Cardiology Services Quality Improvement (ANZACS-QI) registry and stratified based on their Killip class on arrival to the cardiac catheterisation laboratory. Primary outcome was 30-day all-cause mortality. Multivariable analysis was used to identify predictors of mortality prior to PCI and to develop a mortality scoring system. RESULTS: In total, 6,649 patients were identified, including 192 (2.9%) Killip IV (CS) patients. Thirty-day mortality was 47.5% in patients with CS, 14.6% in those with heart failure without shock, and 3% in those without heart failure. Independent predictors of 30-day mortality for patients with CS were: estimated glomerular filtration rate <60 mL/min/1.73m2 (relative risk [RR] 1.89, 95% confidence interval [CI] 1.39-2.58), cardiac arrest (RR 1.54, 95% CI 1.15-2.06), diabetes (RR 1.31, 95% CI 1.01-1.70), female sex (RR 1.32, 95% CI 1.01-1.72), femoral arterial access (RR 1.42, 95% CI 1.06-1.90) and left main stem culprit (RR 2.16, 95% CI 1.65-2.84). A multivariable Shock score was developed which predicts 30-day mortality with good global discrimination (area under the curve 0.79, 95% CI 0.73-0.85). CONCLUSION: In this national cohort, the 30-day mortality for STEMI patients presenting with CS treated with PCI remains high, at nearly 50%. The ANZACS-QI Shock score is a promising tool for mortality risk stratification prior to PCI but requires further validation.

Investigation and treatment after non-ST segment elevation acute coronary syndrome for patients presenting to rural or urban hospitals in Aotearoa New Zealand: ANZACS-QI 75.

AIMS: Compare the care patients with non-ST segment elevation acute coronary syndrome (NSTEACS) received in Aotearoa New Zealand depending on the rural-urban category of the hospital they are first admitted to. METHODS: Patients with NSTEACS investigated with invasive coronary angiogram between 1 January 2014 and 31 December 2019 were included. There were three hospital categories (routine access to percutaneous coronary intervention [urban interventional], other urban [urban non-interventional] and rural) and three ethnicity categories (Maori, Pacific and non-Maori/non-Pacific). Clinical performance measures included: angiography ≤3 days, assessment of left ventricular ejection fraction (LVEF) and prescription of secondary prevention medication. RESULTS: Of 26,779 patients, 66.2% presented to urban-interventional, 25.6% to urban non-interventional and 8.2% to rural hospitals. A smaller percentage of patients presenting to urban interventional than urban non-interventional and rural hospitals were Maori (8.1%, 17.0% and 13.0%). Patients presenting to urban interventional hospitals were more likely to receive timely angiography than urban non-interventional or rural hospitals (78.5%, 60.8% and 63.1%). They were also more likely to have a LVEF assessment (78.5%, 65.4% and 66.3%). In contrast, the use of secondary prevention medications at discharge was similar between hospital categories. Maori and Pacific patients presenting to urban interventional hospitals were less likely than non-Maori/non-Pacific to receive timely angiography but more likely to have LVEF assessed. However, LVEF assessment and timely angiography in urban non-interventional and rural hospitals were lower than in urban interventional hospitals for both Maori and non-Maori/non-Pacific. CONCLUSIONS: Patients presenting to urban hospitals without routine interventional access and rural hospitals were less likely to receive LVEF assessment or timely angiography. This disproportionately impacts Maori, who are more likely to live in these hospital catchments.

Invasive Management and Outcomes in Acute Coronary Syndromes and Chronic Kidney Disease (ANZACS-QI 70).

AIMS: Guidelines recommend management with an invasive coronary angiogram in acute coronary syndromes (ACS), but most studies excluded patients with advanced chronic kidney disease (CKD). Our aims were to describe, in a comprehensive ACS cohort, the incidence of CKD, coronary angiography utilisation and outcomes, according to CKD stage. METHODS: National datasets were used to identify hospitalised ACS patients (2013 to 2018) in the Northern region of New Zealand. CKD stage was obtained from a linked laboratory dataset. Outcomes included all-cause and cause-specific mortality, and non-fatal myocardial infarction, heart failure and stroke. RESULTS: Thirty-eight percent (38%) of the 23,432 ACS patients had CKD stage 3 or higher: 2,403 (10%) had stages 4/5 CKD. Overall 61% received coronary angiography. Compared with normal renal function the adjusted rate of coronary angiography was lower in CKD stage 3b (RR 0.75, 95% confidence intervals [CIs] 0.69, 0.82) and stages 4/5 without dialysis (RR 0.41, 95% CIs 0.36, 0.46), but similar for those on dialysis (RR 0.89, 95% CIs 0.77, 1.02). All-cause mortality (mean follow-up 3.2 years) increased with CKD stage from 8% (normal kidney function) to 69% (stages 4/5 CKD without dialysis). Compared with coronary angiography, the adjusted all-cause and CVD mortality risks were higher in those without coronary angiography, except for those on dialysis, where these risks converged. CONCLUSIONS: Invasive management fell below an eGFR of 45 mL/min (≤ stage 3b), and nearly half of all deaths occurred in these patients. Clinical trials are needed to assess the role of invasive management in ACS and advanced CKD.

Outcomes and access to angiography following non-ST-segment elevation acute coronary syndromes in patients who present to rural or urban hospitals: ANZACS-QI 72.

AIM: This study's aim was to identify differences in invasive angiography performed and health outcomes for patients with non-ST-segment elevation acute coronary syndrome (NSTEACS) presenting to either i) a rural hospital, or an urban hospital ii) with or iii) without routine access to percutaneous intervention (PCI) in New Zealand. METHODS: Patients with NSTEACS between 1 January 2014 and 31 December 2017 were included. Logistic regression was used to model each of the outcome measures: angiography performed within 1 year; 30-day, 1-year and 2-year all-cause mortality; and readmission within 1 year of presentation with either heart failure, a major adverse cardiac event or major bleeding. RESULTS: There were 42,923 patients included. Compared to urban hospitals with access to PCI, the odds of a patient receiving an angiogram were reduced for rural and urban hospitals without routine access to PCI (odds ratio [OR] 0.82 and 0.75) respectively. There was a small increase in the odds of dying at 2 years (OR 1.16), but not 30 days or 1 year for patients presenting to a rural hospital. CONCLUSION: Patients who present to hospitals without PCI are less likely to receive angiography. Reassuringly there is no difference in mortality, except at 2 years, for patients that present to rural hospitals.

What is the Statin Possession Ratio Cut-Off Which Identifies Those at Increased Risk Following Acute Coronary Syndrome (ANZACS-QI 68)?

AIMS: More optimal dispensing of statins is associated with greater cholesterol lowering; however, it is not known whether this translates to improved outcomes following acute coronary syndrome (ACS). The aim of this study was to assess the association between various levels of statin adherence and outcomes following ACS. METHODS: Patients hospitalised with ACS who underwent coronary angiography between 2014-2018 were identified from the All New Zealand ACS Quality Improvement (ANZACS-QI) registry. Medication possession ratio (MPR) was used to assess statin adherence and calculated over 1 year post-discharge using linked pharmaceutical dispensing datasets. Optimal, adequate and suboptimal adherence was defined as an MPR of ≥1.0, 0.8-0.99 and 0-0.79, respectively. A combined outcome of all-cause mortality and rehospitalisation for atherosclerotic disease was identified from 1 year post-discharge through September 2021. Cox proportional hazard models were used to adjust for confounding variables. RESULTS: Of the 30,452 patients, 68% had optimal adherence, 15% adequate adherence and 16% had suboptimal adherence to statins. Mean follow-up was 3.6 years. Those with suboptimal adherence had a higher adjusted risk of the combined outcome compared with those with optimal adherence (HR 1.18, 95% CI 1.11-1.26). There was no significant difference in adjusted outcome between those with optimal and adequate adherence (HR 0.99, 95% CI 0.92-1.06). CONCLUSIONS: Suboptimal statin adherence following ACS is associated with an increased risk of mortality and rehospitalisation. An MPR cut-off of 0.8 seems reasonable to identify those at higher risk of cardiovascular events that could benefit the most from interventions to improve statin adherence and is appropriate as a target for quality improvement programs.

A nurse-led and medically supported outpatient follow-up model following an acute coronary syndrome is as safe and effective as medical follow-up alone (ANZACS-QI 69.

BACKGROUND: At Middlemore Hospital, acute coronary syndrome (ACS) patients are admitted under the care of one of seven cardiologists working on a weekly rotation. Between 2010 and 2018 patients under the care of three of the cardiologists were followed up in a "medical only" post-ACS follow-up clinic model where the cardiologist or registrar saw all patients. Those admitted under the other four cardiologists were seen in a "nurse-led, cardiologist-supported" follow-up model where the majority of patients were seen by a nurse specialist. The study aim was to compare quality of care and outcomes between patients managed under these two follow-up clinic models. METHOD: The ANZACS-QI registry was used to identify all ACS admissions, 2010 to 2018. The ANZACS-QI records for 5296 patients, discharged alive, were anonymously linked with hospital clinic follow-up and national administrative datasets. Time to follow-up, medication dispensation and titration and one-year clinical outcomes were compared for the two follow-up models. RESULTS: Characteristics of patients managed under each model were similar. 4395 patients attended follow up, 74% in the nurse-led model. At one year there were no differences between the medical- and nurse-led cohorts in all-cause mortality (4.6% vs 3.9, p=0.29), rehospitalisations for myocardial infarction (MI) (9.2% vs 8.3%, p=0.31), stroke (1.2% vs 1.4% p=0.71), heart failure (5.7% vs 6.9%, p=0.15) or a combined endpoint of all-cause mortality and/or rehospitalisation for MI/stroke/HF (15.2% vs 14.8%, p=0.71). Patients were seen earlier post-discharge in the nurse-led model, (mean 83 vs 101 days). Medication dispensation one year post-discharge was similar for both models of care. CONCLUSION: The nurse-led model is associated with earlier access to follow-up, was equally as effective at maintaining secondary prevention pharmacotherapy and associated with similar survival and readmission with non-fatal ACS/stroke/heart failure.

Revascularisation and outcomes after acute coronary syndromes in patients with prior coronary artery bypass grafting-ANZACS-QI 67.

AIMS: Coronary angiography in patients with previous coronary artery bypass grafts (CABG) is technically more difficult with increased procedure time, radiation exposure and in-hospital complications. In a contemporary national registry of acute coronary syndrome (ACS) patients undergoing an invasive strategy, we compared the management and outcomes of patients with and without prior CABG. METHODS: The All New Zealand ACS Quality Improvement (ANZACS-QI) registry was used to identify patients admitted to New Zealand public hospitals with an ACS who underwent invasive coronary angiography (2014-2018). Outcomes were ascertained by anonymised linkage to national datasets. RESULTS: Of 26,869 patients, 1,791 (6.7%) had prior CABG and 25,078 (93.3%) had no prior CABG. Prior CABG patients were older (mean age 71 years vs 65 years), more comorbid and less likely to be revascularised than those without CABG (49.8% vs 73.0%). Compared to patients without CABG, at a mean follow-up of 2.1 years, patients with prior CABG had higher all-cause mortality (HR 2.03 (1.80-2.29)), and were more likely to have recurrent myocardial infarction (HR 2.70 (2.40-3.04)), rehospitalisation with congestive cardiac failure (HR 2.36 (2.10-2.66)) and stroke (HR 1.82 (1.41-2.34)). CONCLUSION: In contemporary real-world practice, despite half of the patients with ACS and prior CABG receiving PCI, the outcomes remain poor compared with those without prior CABG.

Guideline-Directed Medical Therapy Before and After Primary Prevention Implantable Cardioverter Defibrillator Implantation in New Zealand (ANZACS-QI 66).

INTRODUCTION: Guidelines recommend angiotensin converting enzyme inhibitors (ACEi)/angiotensin receptor blockers (ARB)/angiotensin receptor neprilysin inhibitors (ARNI); beta blockers; and mineralocorticoid receptor antagonists (MRA) in patients with symptomatic heart failure and reduced left ventricular ejection fraction before consideration of primary prevention implantable cardioverter defibrillator (ICD). This study aims to investigate dispensing rates of guideline-directed medical therapy (GDMT) before and after primary prevention ICD implantation in New Zealand. METHODS: All patients receiving a primary prevention ICD between 2009 and 2018 were identified using nationally collected data on all public hospital admissions in New Zealand. This was anonymously linked to national pharmaceutical data to obtain medication dispensing. Medications were categorised as low dose (<50% of target dose), 50-99% of target dose or target dose based on international guidelines. RESULTS: Of the 1,698 patients identified, ACEi/ARB/ARNI, beta blockers and MRA were dispensed in 80.2%, 83.6% and 45.4%, respectively, prior to ICD implant. However, ≥50% target doses of each medication class were dispensed in only 51.8%, 51.8% and 34.5%, respectively. Only 15.8% of patients were receiving ≥50% target doses of all three classes of medications. In the 1,666 patients who survived 1 year after ICD implant, the proportions of patients dispensed each class of medications remained largely unchanged. CONCLUSION: Dispensing of GDMT was suboptimal in patients before and after primary prevention ICD implantation in New Zealand, and only a minority received ≥50% target doses of all classes of medication. Interventions are needed to optimise use of these standard evidence-based medications to improve clinical outcomes and avoid unnecessary device implantation.

Clinically Acquired High Sensitivity Cardiac Troponin T is a Poor Predictor of Reduced Left Ventricular Ejection Fraction After ST Elevation Myocardial Infarction: A National Cohort Study-ANZACS-QI 65.

OBJECTIVE: Cardiac troponins (cTn) have been used historically to estimate infarct size in ST elevation myocardial infarction (STEMI). Within a resource constrained health care environment, cTn could therefore be used for prioritisation of patients for cardiac imaging, in particular echocardiography. We aimed to determine how useful routinely collected cTn would be in predicting significant left ventricular (LV) impairment. METHODS: All patients in the All New Zealand Acute Coronary Syndrome Quality Improvement (ANZACS-QI) registry with their first episode of STEMI between January 2013 and November 2018, who had high sensitivity troponin T measured, were included. We excluded patients with no left ventricular ejection fraction (LVEF) assessment, known LV dysfunction, or prior myocardial infarction. RESULTS: In total, 3,698 patients were included in the analysis. A higher mean hsTnT (admission and peak) was seen in patients with more severely impaired LV function but there was significant overlap in the range of hsTnT between the different LVEF categories. Cardiac troponins demonstrated poor discriminative ability to either predict or exclude significant LV impairment (LVEF <40%). At an optimal cutpoint of 3,405 ng/L, peak hsTnT had a sensitivity of 56.5% (95% confidence interval [CI] 42-62%), a specificity of 65.3% (95% CI 62-79%) and an area under the receiver operating curve of 0.62 (95% CI 0.60-0.64). CONCLUSION: This is the largest study comparing clinically measured troponin levels and LV function in patients presenting with STEMI. A definite, but weak, association was seen between peak troponin and the degree of LV dysfunction, with significant overlap in troponin levels between levels of myocardial dysfunction. Routinely acquired troponin is not suitable for clinical use as a method of prioritising patients for cardiac imaging.

Prehospital identification of ST-segment elevation myocardial infarction and mortality (ANZACS-QI 61).

BACKGROUND: Early recognition of ST-segment elevation myocardial infarction (STEMI) is needed for timely cardiac monitoring and reperfusion therapy. METHODS: Three anonymously linked New Zealand national datasets (July 2016-November 2018) were used to assess the utilisation of ambulance transport in STEMI cases, the concordance between ambulance initial clinical impressions and hospital STEMI diagnoses, and the association between initial paramedic clinical impressions and 30-day mortality. The St John Ambulance electronic record captures community call-outs and paramedic initial clinical impressions. The national cardiac (ANZACS-QI) registry and national administrative datasets capture all New Zealand public hospital admission diagnoses and mortality data. RESULTS: Of 5465 patients with STEMI, 73% were transported to hospital by ambulance. For these patients, the initial paramedic impression was STEMI in 50.7%, another acute coronary syndrome (ACS) diagnosis in 19.9% and non-ACS diagnosis in 29.7%. Only 37% of the 5465 patients with STEMI were both transported by ambulance and clinically suspected of STEMI by paramedics. Compared with patients with paramedic-'suspected STEMI', 30-day mortality was over threefold higher for patients thought to have a non-ACS condition (10.9% and 34.9%, respectively), but after adjustment for available covariates, this was substantially ameliorated (HR 1.48, 95% CI 1.22 to 1.80). CONCLUSIONS: In this national data linkage study, only 4 out of every 10 patients with STEMI were both transported by ambulance and had STEMI suspected by paramedics. Although patients with STEMI not suspected of an ACS diagnosis by paramedics had the highest mortality rate, this is largely explained by the different risk profile of these patients.

Ten-year trends in cardiac implantable electronic devices in New Zealand: a national data linkage study (ANZACS-QI 51).

BACKGROUND: Implant rates for cardiac implantable electronic devices (CIED), including permanent pacemakers (PPM) and implantable cardioverter defibrillators (ICD), have increased globally in recent decades. AIMS: This is the first national study providing a contemporary analysis of national CIED implant trends by sex-specific age groups over an extended period. METHODS: Patient characteristics and device type were identified for 10 years (2009-2018) using procedure coding in the National Minimum Datasets, which collects all New Zealand (NZ) public hospital admissions. CIED implant rates represent implants/million population. RESULTS: New PPM implant rates increased by 4.6%/year (P < 0.001), increasing in all age groups except patients <40 years. Males received 60.1% of new PPM implants, with higher implant rates across all age groups compared with females. The annual increase in age-standardised implant rates was similar for males and females (3.4% vs 3.0%; P = 0.4). By 2018 the overall PPM implant rate was 538/million. New ICD implant rates increased by 4.2%/year (P < 0.001), increasing in all age groups except patients <40 and ≥ 80 years. Males received 78.1% of new ICD implants, with higher implant rates across all age groups compared to females. The annual increase in age-standardised implant rates was higher in males compared with females (3.5% vs 0.7%; P < 0.001). By 2018 the overall ICD implant rate was 144/million. CONCLUSION: CIED implant rates have increased steadily in NZ over the past decade but remain low compared with international benchmarks. Males had substantially higher CIED implant rates compared with females, with a growing gender disparity in ICD implant rates.

Regional variation in cardiac implantable electronic device implants trends in New Zealand over the past decade (ANZACS-QI 54).

BACKGROUND: Permanent pacemaker (PPM) and implantable cardioverter defibrillator (ICD) implant rates have increased in New Zealand over the past decade. AIMS: To provide a contemporary analysis of regional variation in implant rates. METHODS: New PPM and ICD implants in patients aged ≥15 years were identified for 10 years (2009-2018) using procedure coding in the National Minimum Datasets, which collects all New Zealand public hospital admissions. Age-standardised new implant rates per million adult population were calculated for each of the four regions (Northern, Midland, Central and Southern) and the 20 district health boards (DHB) across those regions. Trend analysis was performed using joinpoint regression. RESULTS: New PPM implant rates increased nationally by 3.4%/year (P < 0.001). The Northern region had the highest new PPM implant rate, increasing by 4.5%/year (P < 0.001). Excluding DHB with <50 000 people, the new PPM implant rate for 2017/2018 was highest in Counties Manukau DHB (854.3/million; 95% confidence interval (CI): 774.9-933.6/million) and lowest in Canterbury DHB (488.6/million; 95% CI: 438.1-539.0/million). New ICD implant rates increased nationally by 3.0%/year (P = 0.002). The Midland region had the highest new ICD implant rate, increasing by 3.8%/year (P = 0.013). Excluding DHB with <50 000 people, the new ICD implant rate for 2017-2018 was highest in the Bay of Plenty DHB (228.5/million; 95% CI: 180.4-276.6/million) and lowest in Canterbury DHB (90.2/million; 95% CI: 69.9-110.4/million). CONCLUSION: There was significant variation in PPM and ICD implant rates across regions and DHB, suggesting potential inequity in patient access across New Zealand.

Both incidence and prevalence of ischaemic heart disease are declining in parallel: a national data-linkage study in New Zealand (ANZACS-QI 52).

AIMS: To examine trends in ischaemic heart disease (IHD) incidence and prevalence in New Zealand from 2005 to 2016, using comprehensive linked national hospitalization and mortality data as proxy measures of all significant events. METHODS AND RESULTS: Incident and prevalent cases of IHD in people aged ≥25 years were identified using individual patient-linkage of routinely collected ICD-10-coded hospitalization and mortality data. Incidence rates and prevalence proportions were calculated by sex and age group and then age-standardized to the 2016 New Zealand population. Ischaemic heart disease incidence and prevalence declined in men and women in all age groups. The average annual rate of decline in age-standardized IHD incidence was 3.3% for women and 2.7% for men, and the rate of decline in age-standardized IHD prevalence was 3.2% for women and 2.2% for men. Despite a 17% increase in the New Zealand population aged 25 years and over during the study period, the total number of people living with IHD also decreased, particularly in those aged 65 years and older. CONCLUSION: In contrast to observations from other countries, where IHD incidence but not IHD prevalence has been falling, declining IHD incidence in New Zealand in recent decades is now mirrored by declining IHD prevalence.

Type of Stressor and Medium-Term Outcomes After Takotsubo Syndrome: What Becomes of the Broken Hearted? (ANZACS-QI 59).

BACKGROUND: Takotsubo syndrome (TS) is often triggered by an acute physical or emotional stressor. We hypothesised that medium-term prognosis may be better for TS patients with an associated emotional stressor than for those with an acute physical illness. METHODS: We identified consecutive TS patients presenting in New Zealand (2006-2018). The clinical presentation and outcomes of TS patients according to types of stressor (physical, emotional or no stressor) were assessed. Post-discharge survival after TS was compared with age- and gender-matched patients after myocardial infarction (MI) and people in the community without known cardiovascular disease (CVD). RESULTS: Of 632 TS patients (95.9% women, mean age 65.0±11.1 years), 27.4% had an associated acute physical stressor, 46.4% an emotional stressor and 26.2% no evident stressor. In-hospital mortality was similar for each group (1.7%, 1.2%, 0.3% respectively, p=0.29). In a median 4.4 years post-discharge there were 54 deaths (53 non-cardiac). Compared with patients without known CVD, TS patients with physical stress and those with MI were less likely to survive (HR 4.46, 95%CI 3.10-6.42; HR 4.23, 95%CI 3.81-4.70 respectively) but survival for TS patients associated with emotional stress or no stressor was similar (HR 1.11, 95%CI 0.66-1.85; HR 1.08, 95%CI 0.54-2.18, respectively). Recurrence was similar among the three groups (p=0.14). CONCLUSION: Takotsubo syndrome associated with physical stressor has a post-discharge mortality risk as high as after MI. In contrast, prognosis for TS triggered by an emotional stressor is excellent, and similar to that of those without known CVD.

How common are non-acute coronary syndrome (ACS) diagnoses in patients with suspected ACS investigated with coronary angiography in New Zealand? (ANZACS-QI 58).

BACKGROUND AND AIMS: The last two decades in New Zealand have seen increased availability of primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) and early invasive coronary angiography (ICA) for other high-risk acute coronary syndrome (ACS) patients. One metric to assess the clinical appropriateness of these invasive strategies is to examine the false-positive rate for the investigation (ie, the rate of non-ACS diagnoses). METHODS: All patients presenting to New Zealand public hospitals with suspected ACS who underwent ICA between 2015 and 2019 were recorded prospectively in the All New Zealand Acute Coronary Syndrome Quality Improvement registry. The cohort was divided according to clinical impression at presentation: (1) suspected STEMI <24h and (2) other suspected ACS. The final discharge diagnosis for each patient were obtained from the registry. RESULTS: There were 6,059 (20%) patients with suspected STEMI <24h and 24,258 (80%) with other suspected ACS. Of the suspected STEMIs <24h, 90.6% had a final diagnosis of STEMI, 3.5% non-ST segment elevation ACS (NSTEACS) and only 5.9% had a non-ACS diagnosis. Of those with other suspected ACS, 80.7% had a final ACS diagnosis. Across all New Zealand district health boards (DHBs), the proportion of non-ACS diagnoses was similar for suspected STEMI presentations. However, for other suspected ACS, the proportions were higher in DHBs with rapid access to coronary interventional facilities than in those without (17.6% vs 7.0%, p<0.001). CONCLUSIONS: False-positive catheter laboratory activations for suspected STEMI patients are low across New Zealand. The differences in the proportion of non-ACS diagnoses according to DHB interventional capability for other suspected ACS requires further investigation.

Obesity and All Cause Mortality Following Acute Coronary Syndrome (ANZACS-QI 53).

BACKGROUND: Some studies have suggested a lower mortality in obese subjects with cardiovascular disease. The aim of this study was to evaluate the relationship between body mass index (BMI) and outcomes in patients with acute coronary syndrome (ACS). METHODS: The study included 13,742 patients undergoing coronary angiography for ACS between 2012 and 2016 from the All New Zealand Acute Coronary Syndrome-Quality Improvement (ANZACS-QI) registry. Patients were categorised by BMI (kg/m2) as: underweight <18.5, normal 18.5 to <25, overweight 25 to <30, mildly obese 30 to <35, moderately obese 35 to <40, and severely obese ≥40. The primary endpoint of the study was all cause mortality with secondary endpoints of cardiovascular disease (CVD) and non-CVD mortality within 4 years of discharge. RESULTS: Unadjusted all cause mortality was lowest in the mildly obese but no different to normal or overweight after adjustment for multiple confounders. Adjusted all cause mortality was higher in the moderately (hazard ratio [HR] 1.39, 95% CI: 1.10-1.75) and severely obese (2.06, 95% CI: 1.57-2.70) compared to the mildly obese. Non-CVD mortality (HR 1.58, 95% CI: 1.12-2.23) was the major contributor to higher all cause mortality in moderately obese patients. Both CVD mortality (HR 2.36, 95% CI: 1.67-3.32) and non-CVD mortality (HR 1.67, 95% CI: 1.07-2.61) contributed to higher all cause mortality in the severely obese. CONCLUSIONS: Moderate and severe obesity is associated with worse survival post ACS influenced by higher non-CVD mortality in moderate/severe obesity and higher CVD mortality in severe obesity.

Demographic differences in the initiation and maintenance of statins in the first year post ACS in New Zealand: a data linkage study (ANZACS-QI 57).

INTRODUCTION: Prior New Zealand studies suggest that only approximately two-thirds of patients who present with an acute coronary syndrome (ACS) are adequately maintained on a statin post-discharge. This could be due to low initiation and/or poor longer-term adherence. AIM: To identify the pattern and adequacy of statin maintenance following ACS from initial prescription to one-year post-discharge. METHODS: All New Zealand Acute Coronary Syndrome Quality Improvement (ANZACS-QI) registry data for consecutive New Zealand residents (2015-2017) who were hospitalised with ACS and managed with coronary angiography were anonymously linked to national datasets to derive a medication possession ratio (MPR) to assess medication maintenance. An MPR ≥0.8 is considered adequate maintenance and ≥1 is considered optimal. RESULTS: Of the 16,557 patients who survived their ACS, 15,431 (93.2%) were prescribed a statin at discharge and 89.8% were dispensed a statin within three months. 79.8% (13,219/16,557) of patients had an MPR ≥0.8 during the first year, but only 61.0% (10,096/16,557) had optimal dispensing over this period. Regression analysis identified the independent predictors of sub-optimal maintenance over the first year as age <45 years, no prior statin and Maori and Pacific ethnicity. CONCLUSION: After ACS discharge, the gap between prescribing and dispensing rates was small with only minor demographic variation. One in ten patients were not initially dispensed a statin. Although eight in ten patients were adequately maintained, only six in ten had optimal maintenance with clear ethnic and age differences, which may reflect more general disparities in healthcare.

Nationwide dispensing of cardioprotective medications during the first year following acute coronary syndrome (ANZACS-QI 56).

AIM: A number of evidence-based medications are recommended following an acute coronary syndrome (ACS), including statins, antithrombotics (antiplatelet and/or anticoagulants), a beta-blocker and an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker (ACE-I/ARB). This study aimed to describe the dispensing of the cardioprotective medications in the first year following an ACS hospitalisation in New Zealand and how this varies according to age, sex and type of coronary intervention. METHOD: National hospitalisation data was used to identify all New Zealand residents aged 35-79 years who were discharged from hospital in the years 2013/14 with a primary discharge diagnosis of ACS. Using anonymous linkage to national pharmaceutical dispensing and mortality datasets, the dispensing of each group of medications was examined in survivors of quarters one, two and four of the first year post discharge. RESULTS: There were 14,496 patients; mean age was 63.4 years and 68.8% were male. Dispensing of medications in survivors steadily fell across quarters one, two and four: 90.8%, 82.1% and 78.8% of patients were dispensed statins; 90.6%, 79.8% and 78.1% were dispensed aspirin; 82.7%, 72.6% and 70.0% were dispensed beta-blockers; 69.6%, 62.7% and 61.3% were dispensed ACE-I/ARB; 67.7%, 53.6% and 40.4% were dispensed a P2Y12 inhibitor; and 68.6%, 53.0% and 40.7% were dispensed a combination of two or more antithrombotics. CONCLUSION: Cardioprotective medication dispensing was lower than would have been the case if the current ACS guidelines were followed. The greatest decrease in dispensing occurred between quarter one and quarter two, which highlights a potentially important period for targeted interventions to improve adherence.

Prognostic significance of mid-range ejection fraction following acute coronary syndrome (ANZACS-QI 23).

AIM: Recommendations regarding medication use after acute coronary syndrome (ACS) are dichotomised according to whether left ventricular ejection fraction (LVEF) is <40% or ≥40%. In the context of heart failure (HF), a mid-range EF (mrEF, 40-49%) confers an intermediate prognosis between reduced EF (rEF, <40%) and preserved EF (pEF, ≥50%). The aim of this study was to describe, in the context of ACS, the frequency of each EF subgroup and their associated outcomes. METHODS: Consecutive patients presenting with ACS who underwent coronary angiography during 2015 were enrolled in the ANZACS-QI (All New Zealand Acute Coronary Syndrome-Quality Improvement) registry. Outcomes were obtained using anonymised linkage to national datasets. Cox proportional hazards models were used to adjust for confounding variables. RESULTS: Of the cohort of 6,216 patients, 31% did not have an LVEF assessment. Of those with a recorded LVEF, 63% had pEF, 21% had mrEF and 16% had rEF. Mean follow-up was 1.5 years. After adjusting for age, sex, clinical risk factors and post-ACS management, those with mrEF and rEF had a higher adjusted risk of all-cause mortality compared to pEF (HR 1.55, 95% CI 1.12-2.15 and HR 2.57, 95% CI 1.89-3.48, respectively). After adjustment, rEF was associated with an increased risk of subsequent HF hospitalisation (HR 2.32, 95% CI 1.75-3.08). CONCLUSIONS: One in five patients post-ACS have mrEF, which is associated with an intermediate risk of morbidity and mortality compared to those with pEF and rEF. Further study is warranted to determine the optimal management for these patients.

Ethnic variation in the trends of new implantable cardioverter defibrillator implants in New Zealand 2005-2019 (ANZACS-QI 63).

AIMS: Ethnic variation in implantable cardioverter defibrillator (ICD) implant rates have been reported internationally but have not previously been examined in New Zealand. This study examined trends in new ICD implants by ethnicity over an extended period. METHODS: All patients who received a new ICD implant between 2005 and 2019 were identified using the National Minimum Dataset, which collects information on all public hospital admissions in New Zealand. Ethnicity was classified using the following standard prioritisation: Maori, Pacific, Asian and European/Other. New ICD implant rates were analysed by ethnicity and age groups. RESULTS: A total of 5,514 new ICDs were implanted. New ICD implant rates increased from 41.4/million in 2005 to 98.2/million in 2019, an average increase of 5.4%/year (p<0.01). The highest age-standardised implant rates were among Maori, followed by Pacific, European/Other and Asian ethnicities. The largest increase was seen in Pacific people at 8.9%/year (p<0.01), followed by Maori and Asian people at 4.7%/year and 4.3%/year respectively (both p<0.01). In European/Other patients, ICD implant rates increased by 10.3%/year (p<0.01) between 2005 to 2012, then plateaued at -0.4%/year (p=0.71) between 2012 to 2019. By 2019, the age-standardised implant rates in Maori and Pacific people were two-fold higher than European/Others. CONCLUSION: There is marked ethnic variation in ICD implant rates in New Zealand. The higher implant rates in Maori and Pacific parallel known ethnic differences in rates of underlying cardiac disease. The more rapid increase in implant rates in these ethnic groups may represent more equitable treatment over time.