Mild Hypercapnia or Normocapnia after Out-of-Hospital Cardiac Arrest.

BACKGROUND: Guidelines recommend normocapnia for adults with coma who are resuscitated after out-of-hospital cardiac arrest. However, mild hypercapnia increases cerebral blood flow and may improve neurologic outcomes. METHODS: We randomly assigned adults with coma who had been resuscitated after out-of-hospital cardiac arrest of presumed cardiac or unknown cause and admitted to the intensive care unit (ICU) in a 1:1 ratio to either 24 hours of mild hypercapnia (target partial pressure of arterial carbon dioxide [Paco2], 50 to 55 mm Hg) or normocapnia (target Paco2, 35 to 45 mm Hg). The primary outcome was a favorable neurologic outcome, defined as a score of 5 (indicating lower moderate disability) or higher, as assessed with the use of the Glasgow Outcome Scale-Extended (range, 1 [death] to 8, with higher scores indicating better neurologic outcome) at 6 months. Secondary outcomes included death within 6 months. RESULTS: A total of 1700 patients from 63 ICUs in 17 countries were recruited, with 847 patients assigned to targeted mild hypercapnia and 853 to targeted normocapnia. A favorable neurologic outcome at 6 months occurred in 332 of 764 patients (43.5%) in the mild hypercapnia group and in 350 of 784 (44.6%) in the normocapnia group (relative risk, 0.98; 95% confidence interval [CI], 0.87 to 1.11; P = 0.76). Death within 6 months after randomization occurred in 393 of 816 patients (48.2%) in the mild hypercapnia group and in 382 of 832 (45.9%) in the normocapnia group (relative risk, 1.05; 95% CI, 0.94 to 1.16). The incidence of adverse events did not differ significantly between groups. CONCLUSIONS: In patients with coma who were resuscitated after out-of-hospital cardiac arrest, targeted mild hypercapnia did not lead to better neurologic outcomes at 6 months than targeted normocapnia. (Funded by the National Health and Medical Research Council of Australia and others; TAME ClinicalTrials.gov number, NCT03114033.).

Multimorbidity impacts cardiovascular disease risk following percutaneous coronary intervention: latent class analysis of the Melbourne Interventional Group (MIG) registry.

BACKGROUND: Multimorbidity is strongly associated with disability or functional decline, poor quality of life and high consumption of health care services. This study aimed (1) To identify patterns of multimorbidity among patients undergoing first recorded percutaneous coronary intervention (PCI); (2) To explore the association between the identified patterns of multimorbidity on length of hospital stay, 30-day and 12- month risk of major adverse cardiac and cerebrovascular events (MACCE) after PCI. METHODS: A retrospective cohort study of the Melbourne Interventional Group (MIG) registry. This study included 14,025 participants who underwent their first PCI from 2005 to 2015 in Victoria, Australia. Based on a probabilistic modelling approach, Latent class analysis was adopted to classify clusters of people who shared similar combinations and magnitude of the comorbidity of interest. Logistic regression models were used to estimate odd ratios and 95% confidence interval (CI) for the 30-day and 12-month MACCE. RESULTS: More than two-thirds of patients had multimorbidity, with the most prevalent conditions being hypertension (59%) and dyslipidaemia (60%). Four distinctive multimorbidity clusters were identified each with significant associations for higher risk of 30-day and 12-month MACCE. The cluster B had the highest risk of 30-day MACCE event that was characterised by a high prevalence of reduced estimated glomerular filtration rate (92%), hypertension (73%) and reduced ejection fraction (EF) (57%). The cluster C, characterised by a high prevalence of hypertension (94%), dyslipidaemia (88%), reduced eGFR (87%), diabetes (73%) and reduced EF (65%) had the highest risk of 12-month MACCE and highest length of hospital stay. CONCLUSION: Hypertension and dyslipidaemia are prevalent in at least four in ten patients undergoing coronary angioplasty. This study showed that clusters of patients with multimorbidity had significantly different risk of 30-day and 12-month MACCE after PCI. This suggests the necessity for treatment approaches that are more personalised and customised to enhance patient outcomes and the quality of care delivered to patients in various comorbidity clusters. These results should be validated in a prospective cohort and to evaluate the potential impacts of these clusters on the prevention of MACCE after PCI.

Artificial neural networks for ECG interpretation in acute coronary syndrome: A scoping review.

INTRODUCTION: The electrocardiogram (ECG) is a crucial diagnostic tool in the Emergency Department (ED) for assessing patients with Acute Coronary Syndrome (ACS). Despite its widespread use, the ECG has limitations, including low sensitivity of the STEMI criteria to detect Acute Coronary Occlusion (ACO) and poor inter-rater reliability. Emerging ECG features beyond the traditional STEMI criteria show promise in improving early ACO diagnosis, but complexity hinders widespread adoption. The potential integration of Artificial Neural Networks (ANN) holds promise for enhancing diagnostic accuracy and addressing reliability issues in ECG interpretation for ACO symptoms. METHODS: Ovid MEDLINE, CINAHL, EMBASE, Cochrane, PubMed and Scopus were searched from inception through to 8th of December 2023. A thorough search of the grey literature and reference lists of relevant articles was also performed to identify additional studies. Articles were included if they reported the use of ANN for ECG interpretation of Acute Coronary Syndrome in the Emergency Department patients. RESULTS: The search yielded a total of 244 articles. After removing duplicates and excluding non-relevant articles, 14 remained for analysis. There was significant heterogeneity in the types of ANN models used and the outcomes assessed, making direct comparisons challenging. Nevertheless, ANN appeared to demonstrate higher accuracy than physician interpreters for the evaluated outcomes and this proved independent of both specialty and years of experience. CONCLUSIONS: The interpretation of ECGs in patients with suspected ACS using ANN appears to be accurate and potentially superior when compared to human interpreters and computerised algorithms. This appears consistent across various ANN models and outcome variables. Future investigations should emphasise ANN interpretation of ECGs in patients with ACO, where rapid and accurate diagnosis can significantly benefit patients through timely access to reperfusion therapies.

Preoperative Variables of 30-Day Mortality in Adults Undergoing Percutaneous Coronary Intervention: A Systematic Review.

BACKGROUND AND AIM: Risk adjustment following percutaneous coronary intervention (PCI) is vital for clinical quality registries, performance monitoring, and clinical decision-making. There remains significant variation in the accuracy and nature of risk adjustment models utilised in international PCI registries/databases. Therefore, the current systematic review aims to summarise preoperative variables associated with 30-day mortality among patients undergoing PCI, and the other methodologies used in risk adjustments. METHOD: The MEDLINE, EMBASE, CINAHL, and Web of Science databases until October 2022 without any language restriction were systematically searched to identify preoperative independent variables related to 30-day mortality following PCI. Information was systematically summarised in a descriptive manner following the Checklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling Studies checklist. The quality and risk of bias of all included articles were assessed using the Prediction Model Risk Of Bias Assessment Tool. Two independent investigators took part in screening and quality assessment. RESULTS: The search yielded 2,941 studies, of which 42 articles were included in the final assessment. Logistic regression, Cox-proportional hazard model, and machine learning were utilised by 27 (64.3%), 14 (33.3%), and one (2.4%) article, respectively. A total of 74 independent preoperative variables were identified that were significantly associated with 30-day mortality following PCI. Variables that repeatedly used in various models were, but not limited to, age (n=36, 85.7%), renal disease (n=29, 69.0%), diabetes mellitus (n=17, 40.5%), cardiogenic shock (n=14, 33.3%), gender (n=14, 33.3%), ejection fraction (n=13, 30.9%), acute coronary syndrome (n=12, 28.6%), and heart failure (n=10, 23.8%). Nine (9; 21.4%) studies used missing values imputation, and 15 (35.7%) articles reported the model's performance (discrimination) with values ranging from 0.501 (95% confidence interval [CI] 0.472-0.530) to 0.928 (95% CI 0.900-0.956), and four studies (9.5%) validated the model on external/out-of-sample data. CONCLUSIONS: Risk adjustment models need further improvement in their quality through the inclusion of a parsimonious set of clinically relevant variables, appropriately handling missing values and model validation, and utilising machine learning methods.

Post-Procedure Monocyte Count Levels Predict Major Adverse Cardiovascular Events (MACE) Following Transcatheter Aortic Valve Implantation (TAVI) for Aortic Stenosis.

BACKGROUND: Aortic stenosis has recently been characterised as having an inflammatory aetiology, beyond the traditional degenerative model. Recruitment of monocytes has been associated with inflammation contributing to progression of calcific aortic-valve disease. Prior research has demonstrated that pre-procedure inflammatory biomarkers do not consistently discriminate poorer outcomes in those with aortic stenosis. It remains, however, unclear if postprocedure inflammatory biomarkers, which are influenced by intraprocedural pro-inflammatory insults, can predict major adverse cardiovascular events (MACE) post transcatheter aortic valve implantation (TAVI). METHOD: All patients with postprocedure monocyte levels undergoing transcatheter aortic valve implantation at The Alfred Hospital, Melbourne, Australia (2008-2019) were included. The highest monocyte count from postprocedure days 1 to 3 was used. Patients were divided into "high" or "low" postprocedure monocyte count groups using the Youden Index. The incidence of 30-day MACE a composite of stroke, acute myocardial infarction, and death) was then compared. RESULTS: In total, 472 patients were included (54% men, median age 84 years). Fourteen (14) patients (3%) suffered a 30-day MACE. Those with high postprocedure monocyte count were more likely to: be hypertensive (p=0.049); have a higher Society of Thoracic Surgeons risk score (p=0.032); and, undergo non-transfemoral access (p=0.018). A high (≥0.975) postprocedure monocyte count was significantly associated with 30-day MACE (odds ratio [OR] 1.16 for each 0.1 increase in monocyte, p=0.025). This association remained present on multivariable analysis adjusted for age, sex, Society of Thoracic Surgeons risk score, and self-expanding valve prosthesis type (OR 1.17, p=0.028). CONCLUSIONS: The association between postprocedure monocytosis and 30-day MACE suggests that minimising peri-procedural inflammatory insults may improve outcomes. This inexpensive and readily available biomarker may also aid in tailored risk stratification for patients.

The Role of Comorbidities in Predicting Functional Improvement After Transcatheter Aortic Valve Implantation.

BACKGROUND: Patients undergoing transcatheter aortic valve implantation (TAVI) have a high comorbidity burden. We sought to stratify patients into functional outcomes using the Kansas City Cardiomyopathy Questionnaire (KCCQ-12), a patient-reported outcome with benefits over both the New York Heart Association (NYHA) classification and the original 23-item KCCQ, and to evaluate the importance of comorbidities in predicting failure of functional improvement post-TAVI in a contemporary cohort. METHODS: In total, 366 patients with severe aortic stenosis undergoing TAVI with baseline KCCQ-12 were retrospectively analysed and divided into two groups. Failure to improve was defined as a score <60 and a change in score <10 at 1 year in either overall score (KCCQ-OS) or clinical summary score (KCCQ-CSS). RESULTS: Failure to improve was noted in 13% of patients, who were more likely to have lower KCCQ-OS at baseline (47 [35-59] vs 56 [42-74]), chronic obstructive pulmonary disease (COPD) (19% vs 8%), severe chronic kidney disease (CKD) (13% vs 2%), a clinical frailty score (CFS) ≥5 (41% vs 14%), and lower serum albumin (36 g/L [34-38] vs 38 g/L [35-40]). On multivariate analysis, with an area under the curve of 0.71 (0.63-0.78), baseline KCCQ-OS (adjusted odds ratio [aOR] 0.3 [0.1-0.6], p=0.04), COPD (aOR 2.8 [1.2-6.5], p=0.02), and severe CKD (aOR 5.7 [1.7-18.5], p=0.004) remained independent predictors. CFS alone had a similar predictive value as the multivariable model (OR 2.0 [1.3-3.4], area under the curve 0.69 [0.59-0.80], p<0.001). CONCLUSIONS: KCCQ scores were effective in delineating functional outcomes, with most patients in our relatively lower surgical risk cohort showing significant functional improvements post-TAVI. Low baseline KCCQ, moderate or worse COPD, and severe CKD were associated with failure of improvement post-TAVI. Baseline CFS appears to be a good screening tool to predict poor improvement. These factors should be evaluated and weighted accordingly in pre-TAVI assessments and decision-making.

Acute Kidney Injury Following Transcatheter Aortic Valve Implantation-A Contemporary Perspective of Incidence, Predictors, and Outcomes.

BACKGROUND: Acute kidney injury (AKI) is a known complication following transcatheter aortic valve implantation (TAVI), associated with increased morbidity and mortality. Most of this data relates to higher-risk patients with early-generation TAVI valves. With TAVI now established as a safe and cost-effective procedure for low-risk patients, there is a distinct need for updated analysis. We aimed to assess the incidence, predictors, and outcomes of AKI in a contemporary cohort of TAVI patients, concurrently examining the role of temporal evolution on AKI. METHOD: A total of 2,564 patients undergoing TAVI from 2008-2023 included in the Alfred-Cabrini-Epworth (ACE) TAVI Registry were analysed. Patients were divided into AKI and no AKI groups. Outcomes were reported according to the Valve Academic Research Consortium-3 (VARC-3) criteria. RESULTS: Of 2,564 patients, median age 83 (78-87) years, 57.4% men and a median Society of Thoracic Surgeons score of 3.6 (2.4-5.5), 163 (6.4%) patients developed AKI with incidence falling from 9.7% between 2008-2014 to 6% between 2015-2023 (p=0.022). On multivariable analysis, independent predictors of AKI were male sex (adjusted odds ratio [aOR] 1.89, p=0.005), congestive cardiac failure (aOR 1.52, p=0.048), estimated glomerular filtration rate 30-59 (aOR: 2.79, p<0.001), estimated glomerular filtration rate <30 (aOR 8.65, p<0.001), non-femoral access (aOR 5.35, p<0.001), contrast volume (aOR 1.01, p<0.001), self-expanding valve (aOR 1.60, p=0.045), and bleeding (aOR 2.88, p=0.005). Acute kidney injury was an independent predictor of 30-day (aOR: 6.07, p<0.001) and 12-month (aOR: 3.01, p=0.002) mortality, an association that remained consistent when excluding TAVIs performed prior to 2015. CONCLUSIONS: Acute kidney injury remains a relatively common complication of TAVI, associated with significant morbidity and mortality even in less comorbid, contemporary practice patients.

Structured Weaning From the Impella Left Ventricular Micro-Axial Pump in Acute Myocardial Infarction With Cardiogenic Shock and Protected Percutaneous Coronary Intervention: Experience From a Non-Cardiac Surgical Centre.

BACKGROUND: The Impella (Abiomed, Danvers, MA, USA) temporary percutaneous left ventricular assist device is increasingly used as mechanical circulatory support in patients with acute myocardial infarction-cardiogenic shock (AMICS) or those undergoing high-risk protected percutaneous coronary intervention (PCI). The optimal weaning regimen remains to be defined. METHOD: We implemented a structured weaning protocol in a series of 10 consecutive patients receiving Impella support for protected PCI or AMICS treated with PCI in a high volume non-cardiac surgery centre. Weaning after revascularisation was titrated to native heart recovery using both haemodynamic and echocardiographic parameters. RESULTS: Ten patients (eight male, two female; aged 43-70 years) received Impella support for AMICS (80%) or protected PCI (20%). Cardiogenic shock was of Society for Cardiac Angiography & Interventions grade C-E of severity in 80%, and median left ventricular end-diastolic pressure was 31 mmHg. Protocol implementation allowed successful weaning in eight of 10 patients with a median support time of 29 hours (range, 4-48 hours). Explantation was associated with an increase in heart rate (81 vs 88 bpm; p=0.005), but no significant change in Cardiac Index (2.9 vs 2.9 L/min/m2), mean arterial pressure (79 vs 82 mmHg), vasopressor requirement (10% vs 10%), or serum lactate (1.0 vs 1.0). Median durations of intensive care and hospital stay were 3 and 6 days, respectively. At 30 days, the mortality rate was 20%, with median left ventricular ejection fraction of 40%. CONCLUSIONS: A structured and dynamic weaning protocol for patients with AMICS and protected PCI supported by the Impella device is feasible in a non-cardiac surgery centre. Larger studies are needed to assess generalisability of such a weaning protocol.

Comparison of Characteristics and Outcomes in Patients With Acute Decompensated Heart Failure Admitted Under General Medicine and Cardiology Units.

BACKGROUND: Acute decompensated heart failure (ADHF) is a leading cause of cardiovascular disease hospitalisations associated with significant morbidity and mortality. In hospitals, HF patients are typically managed by cardiology or physician teams, with differences in patient demographics and clinical outcomes. This study utilises contemporary HF registry data to compare patient characteristics and outcomes in those with ADHF admitted into General Medicine and Cardiology units. METHODS: The Victorian Cardiac Outcomes Registry was utilised to identify patients hospitalised with ADHF 30-day period in each of four consecutive years. We compared patient characteristics, pharmacological management and outpatient follow-up of patients admitted to General Medicine and Cardiology units. Primary outcome measures included in-hospital mortality, 30-day readmission, and 30-day mortality. RESULTS: Between 2014 and 2017, a total of 1,253 patients with ADHF admissions were registered, with 53% admitted in General Medicine units and 47% in Cardiology units. General Medicine patients were more likely to be older (82 vs 71 years; p<0.001), female (51% vs 34%; p<0.001), and have higher prevalence of comorbidities and preserved left ventricular function (p<0.001). There were no differences in primary outcome measures between General Medicine and Cardiology in terms of: in-hospital mortality (5.0% vs 3.9%; p=0.35), 30-day readmission (23.4% vs 23.6%; p=0.93), and 30-day mortality (10.0% vs 8.0%; p=0.21). CONCLUSIONS: Hospitalised patients with HF continue to have high mortality and rehospitalisation rates. The choice of treatment by General Medicine or Cardiology units, based on the particular medical profile and individual needs of the patients, provides equivalent outcomes.

Prevalence and Predictors of Emergency Medical Service Use in Patients Undergoing Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction.

AIM: We aim to describe prevalence of Emergency Medical Service (EMS) use, investigate factors predictive of EMS use, and determine if EMS use predicts treatment delay and mortality in our ST-elevation myocardial infarction (STEMI) cohort. METHOD: We prospectively collected data on 5,602 patients presenting with STEMI for primary percutaneous coronary intervention (PCI) transported to PCI-capable hospitals in Victoria, Australia, from 2013-2018 who were entered into the Victorian Cardiac Outcomes Registry (VCOR). We linked this dataset to the Ambulance Victoria and National Death Index (NDI) datasets. We excluded late presentation, thrombolysed, and in-hospital STEMI, as well as patients presenting with cardiogenic shock and out-of-hospital cardiac arrest. RESULTS: In total, 74% of patients undergoing primary PCI for STEMI used EMS. Older age, female gender, higher socioeconomic status, and a history of prior ischaemic heart disease were independent predictors of using EMS. EMS use was associated with shorter adjusted door-to-balloon (53 vs 72 minutes, p<0.001) and symptom-to-balloon (183 vs 212 minutes, p<0.001) times. Mode of transport was not predictive of 30-day or 12-month mortality. CONCLUSIONS: EMS use in Victoria is relatively high compared with internationally reported data. EMS use reduces treatment delay. Predictors of EMS use in our cohort are consistent with those prevalent in prior literature. Understanding the patients who are less likely to use EMS might inform more targeted education campaigns in the future.

Clinical Outcomes of Renal Transplant Recipients Undergoing Percutaneous Coronary Intervention.

BACKGROUND: Clinical outcomes of patients with renal transplant (RT) undergoing percutaneous coronary intervention (PCI) remain poorly elucidated. METHOD: Between 2014 and 2021, data were analysed for the following three groups of patients undergoing PCI enrolled in a multicentre Australian registry: (1) RT recipients (n=226), (2) patients on dialysis (n=992), and (3) chronic kidney disease (CKD) patients (estimated glomerular filtration rate [eGFR], 30‒60 mL/min per 1.73 m2) without previous RT (n=15,534). Primary outcome was 30-day major adverse cardiac and cerebrovascular events (MACCEs)-composite of mortality, myocardial infarction, stent thrombosis, target vessel revascularisation, and stroke. RESULTS: RT recipients were younger than dialysis and patients with CKD (61±10 vs 68±12 vs 78±8.2 years, p<0.001). Patients with RT less frequently had severe left ventricular dysfunction compared with dialysis and CKD groups (6.7% vs 14% and 8.5%); however more, often presented with acute coronary syndrome (58% vs 52% and 48%), especially STEMI (all p<0.001). Patients with RT and CKD had lower rates of 30-day MACCE (4.4% and 6.8% vs 11.6%, p<0.001) than the dialysis group. Three-year survival was similar between RT and CKD groups, however was lower in the dialysis group (80% and 83% vs 60%, p<0.001). After adjustment, dialysis was an independent predictor of 30-day MACCE (odds ratio [OR] 1.90, 95% confidence interval [CI] 1.44‒2.50, p<0.001), however RT was not (OR 0.91, CI 0.42‒1.96, p=0.802). Both RT (hazard ratio [HR] 2.07, CI 1.46‒2.95, p<0.001) and dialysis (HR 1.35, CI 1.02‒1.80, p=0.036) heightened the hazard of long-term mortality. CONCLUSIONS: RT recipients have more favourable clinical outcomes following PCI compared with patients on dialysis. However, despite having similar short-term outcomes to patients with CKD, the hazard of long-term mortality is significantly greater for RT recipients.

Effect of COVID-19 Pandemic Lockdown on Emergency Medical Service Utilisation, and Percutaneous Coronary Intervention Volume-An Australian Perspective.

BACKGROUND: Acute coronary syndrome (ACS) admissions and percutaneous coronary intervention (PCI) volume declined during periods of COVID-19 lockdown internationally in 2020. The effect of lockdown on emergency medical service (EMS) utilisation, and PCI volume during the initial phase of the pandemic in Australia has not been well described. METHOD: We analysed data from the Victorian Cardiac Outcomes Registry (VCOR), a state-wide PCI registry, linked with the Ambulance Victoria EMS registry. PCI volume, 30-day major adverse cardiovascular and cerebrovascular events (MACCE; composite of mortality, myocardial infarction, stent thrombosis, unplanned revascularisation, and stroke), and EMS utilisation were compared over four time periods: lockdown (26 Mar 2020-12 May 2020); pre-lockdown (26 Feb 2020-25 Mar 2020); post-lockdown (13 May 2020-10 Jul 2020); and the year prior (26 Mar 2019-12 May 2019). Interrupted time series analysis was performed to assess PCI trends within and between consecutive periods. RESULTS: The EMS utilisation for ACS during lockdown was higher compared with other periods: lockdown 39.4% vs pre-lockdown 29.7%; vs post-lockdown 33.6%; vs year prior 27.1%; all p<0.01. Median daily PCI cases were similar: 31 (IQR 10, 38) during lockdown; 39 (15, 49) pre-lockdown; 39.5 (11, 44) post-lockdown; and, 42 (10, 49) the year prior; all p>0.05. Median door-to-procedure time for ACS indication during lockdown was shorter at 3 hours (1.2, 20.6) vs pre-lockdown 3.9 (1.7, 21); vs post-lockdown 3.5 (1.5, 21.26); and, the year prior 3.5 (1.5, 23.7); all p<0.05. Lockdown period was associated with lower odds for 30-day MACCE compared to pre-lockdown (odds ratio [OR] 0.55 [0.33-0.93]; p=0.026); post-lockdown (OR 0.66; [0.40-1.06]; p=0.087); and the year prior (OR 0.55 [0.33-0.93]; p=0.026). CONCLUSIONS: Contrary to international trends, EMS utilisation for ACS increased during lockdown but PCI volumes remained similar throughout the initial stages of the pandemic in Victoria, with no observed adverse effect on 30-day MACCE during lockdown. These data suggest that the public health response in Victoria was not associated with poorer quality cardiovascular care in patients receiving PCI.

Alcohol Abstinence in Drinkers with Atrial Fibrillation.

BACKGROUND: Excessive alcohol consumption is associated with incident atrial fibrillation and adverse atrial remodeling; however, the effect of abstinence from alcohol on secondary prevention of atrial fibrillation is unclear. METHODS: We conducted a multicenter, prospective, open-label, randomized, controlled trial at six hospitals in Australia. Adults who consumed 10 or more standard drinks (with 1 standard drink containing approximately 12 g of pure alcohol) per week and who had paroxysmal or persistent atrial fibrillation in sinus rhythm at baseline were randomly assigned in a 1:1 ratio to either abstain from alcohol or continue their usual alcohol consumption. The two primary end points were freedom from recurrence of atrial fibrillation (after a 2-week "blanking period") and total atrial fibrillation burden (proportion of time in atrial fibrillation) during 6 months of follow-up. RESULTS: Of 140 patients who underwent randomization (85% men; mean [±SD] age, 62±9 years), 70 were assigned to the abstinence group and 70 to the control group. Patients in the abstinence group reduced their alcohol intake from 16.8±7.7 to 2.1±3.7 standard drinks per week (a reduction of 87.5%), and patients in the control group reduced their alcohol intake from 16.4±6.9 to 13.2±6.5 drinks per week (a reduction of 19.5%). After a 2-week blanking period, atrial fibrillation recurred in 37 of 70 patients (53%) in the abstinence group and in 51 of 70 patients (73%) in the control group. The abstinence group had a longer period before recurrence of atrial fibrillation than the control group (hazard ratio, 0.55; 95% confidence interval, 0.36 to 0.84; P = 0.005). The atrial fibrillation burden over 6 months of follow-up was significantly lower in the abstinence group than in the control group (median percentage of time in atrial fibrillation, 0.5% [interquartile range, 0.0 to 3.0] vs. 1.2% [interquartile range, 0.0 to 10.3]; P = 0.01). CONCLUSIONS: Abstinence from alcohol reduced arrhythmia recurrences in regular drinkers with atrial fibrillation. (Funded by the Government of Victoria Operational Infrastructure Support Program and others; Australian New Zealand Clinical Trials Registry number, ACTRN12616000256471.).

Long-term impact of the 2014 Hazelwood coal mine fire on emergency department presentations in Australia.

BACKGROUND: In 2014, wildfires ignited a coal mine in Australia, burning for 6 weeks, releasing large amounts of fine particulate matter ≤2.5 µm in diameter (PM2.5). We investigated the association between individual PM2.5 exposure and emergency department presentations (EDPs) within 5 years post-fire. METHODS: Survey and exposure data for 2725 residents from an exposed and unexposed town were linked with ED administrative data from 2009 to 2019. The association between individual PM2.5 and EDPs was assessed using recurrent survival analysis. RESULTS: A 10 µg/m3 increase in PM2.5 was associated with a 10% increase in respiratory EDPs (HR = 1.10; 95%CI:1.00-1.22) over 5 years post-fire. Increased risks of EDPs for ischaemic heart disease (HR = 1.39; 95%CI:1.12-1.73), atherothrombotic disease (HR = 1.27; 95%CI:1.08-1.50), and cardiovascular disease (HR = 1.10, 95%CI:0.99-1.22) were evident within 2.5 years. CONCLUSION: PM2.5 exposure from a 6-week mine fire increased the 5-year risk of respiratory conditions. An increased risk of CVD within 2.5 years post-fire subsided after this time.

Inconsistent discharge diagnoses for young cardiac arrest episodes: insights from a statewide registry.

BACKGROUND: Administrative coding of out-of-hospital cardiac arrest (OHCA) is heterogeneous, with the prevalence of noninformative diagnoses uncertain. AIM: To characterize the prevalence and type of non-informative diagnoses in a young cardiac arrest population. METHODS: Hospital discharge diagnoses provided to a statewide OHCA registry were characterised as either 'informative' or 'noninformative.' Informative diagnoses stated an OHCA had occurred or defined OHCA as occurring due to coronary artery disease, cardiomyopathy, channelopathy, definite noncardiac cause, or no known cause. Noninformative diagnoses were blank, stated presenting cardiac rhythm only, provided irrelevant information or presented a complication of the OHCA as the main diagnosis. Characteristics of patients receiving informative versus noninformative diagnoses were compared. RESULTS: Of 1479 patients with OHCA aged 1 to 50 years, 290 patients were admitted to 15 hospitals. Ninety diagnoses (31.0%) were noninformative (arrest rhythm = 50, blank = 21, complication = 10 and irrelevant = 9). Two hundred diagnoses (69.0%) were informative (cardiac arrest = 84, coronary artery disease = 54, noncardiac diagnosis = 48, cardiomyopathy = 8, arrhythmia disorder = 4 and unascertained = 2). Only 10 diagnoses (3.5%) included both OHCA and an underlying cause. Patients receiving a noninformative diagnosis were more likely to have survived OHCA or been referred for forensic assessment (P = 0.011) and had longer median length of stay (9 vs 5 days, P = 0.0019). CONCLUSION: Almost one third of diagnoses for young patients discharged after an OHCA included neither OHCA nor any underlying cause. Underestimating the burden of OHCA impacts ongoing patient and at-risk family care, data sampling strategies, international statistics and research funding.

Healthcare cost burden of acute chest pain presentations.

BACKGROUND: This study aimed to estimate the direct healthcare cost burden of acute chest pain attendances presenting to ambulance in Victoria, Australia, and to identify key cost drivers especially among low-risk patients. METHODS: State-wide population-based cohort study of consecutive adult patients attended by ambulance for acute chest pain with individual linkage to emergency and hospital admission data in Victoria, Australia (1 January 2015-30 June 2019). Direct healthcare costs, adjusted for inflation to 2020-2021 ($A), were estimated for each component of care using a casemix funding method. RESULTS: From 241 627 ambulance attendances for chest pain during the study period, mean chest pain episode cost was $6284, and total annual costs were estimated at $337.4 million ($68 per capita per annum). Total annual costs increased across the period ($310.5 million in 2015 vs $384.5 million in 2019), while mean episode costs remained stable. Cardiovascular conditions (25% of presentations) were the most expensive (mean $11 523, total annual $148.7 million), while a non-specific pain diagnosis (49% of presentations) was the least expensive (mean $3836, total annual $93.4 million). Patients classified as being at low risk of myocardial infarction, mortality or hospital admission (Early Chest pain Admission, Myocardial infarction, and Mortality (ECAMM) score) represented 31%-57% of the cohort, with total annual costs estimated at $60.6 million-$135.4 million, depending on the score cut-off used. CONCLUSIONS: Total annual costs for acute chest pain presentations are increasing, and a significant proportion of the cost burden relates to low-risk patients and non-specific pain. These data highlight the need to improve the cost-efficiency of chest pain care pathways.

Impact of prehospital opioid dose on angiographic and clinical outcomes in acute coronary syndromes.

BACKGROUND: An adverse interaction whereby opioids impair and delay the gastrointestinal absorption of oral P2Y12 inhibitors has been established, however the clinical significance of this in acute coronary syndrome (ACS) is uncertain. We sought to characterise the relationship between prehospital opioid dose and clinical outcomes in patients with ACS. METHODS: Patients given opioid treatment by emergency medical services (EMS) with ACS who underwent percutaneous coronary intervention (PCI) between 1 January 2014 and 31 December 2018 were included in this retrospective cohort analysis using data linkage between the Ambulance Victoria, Victorian Cardiac Outcomes Registry and Melbourne Interventional Group databases. Patients with cardiogenic shock, out-of-hospital cardiac arrest and fibrinolysis were excluded. The primary end point was the risk-adjusted odds of 30-day major adverse cardiac events (MACE) between patients who received opioids and those that did not. RESULTS: 10 531 patients were included in the primary analysis. There was no significant difference in 30-day MACE between patients receiving opioids and those who did not after adjusting for key patient and clinical factors. Among patients with ST-elevation myocardial infarction (STEMI), there were significantly more patients with thrombolysis in myocardial infarction (TIMI) 0 or 1 flow pre-PCI in a subset of patients with high opioid dose versus no opioids (56% vs 25%, p<0.001). This remained significant after adjusting for known confounders with a higher predicted probability of TIMI 0/1 flow in the high versus no opioid groups (33% vs 11%, p<0.001). CONCLUSIONS: Opioid use was not associated with 30-day MACE. There were higher rates of TIMI 0/1 flow pre-PCI in patients with STEMI prescribed opioids. Future prospective research is required to verify these findings and investigate alternative analgesia for ischaemic chest pain.

Declining Public Awareness of Heart Attack Warning Symptoms in the Years Following an Australian Public Awareness Campaign: A Cross-Sectional Study.

BACKGROUND: The National Heart Foundation of Australia's (NHFA) Warning Signs campaign ran between 2010 and 2013. This study examines trends in Australian adults' ability to name heart attack symptoms during the campaign and in the years following. METHODS: Using the NHFA's HeartWatch data (quarterly online surveys) for adults aged 30-59 years, we conducted an adjusted piecewise regression analysis comparing trends in the ability to name symptoms during the campaign period plus one year lag (2010-2014) to the post-campaign period (2015-2020) RESULTS: Over the study period, there were 101,936 Australian adults surveyed. Symptom awareness was high or increased during the campaign period. However, there was a significant downward trend in each year following the campaign period for most symptoms (e.g., chest pain: adjusted odds ratio [AOR] =0.91, 95%CI: 0.56-0.80; arm pain: AOR=0.92, 95%CI: 0.90-0.94). Conversely, the inability to name any heart attack symptom increased in each year following the campaign (3.7% in 2010 to 19.9% in 2020; AOR=1.13, 95%CI: 1.10-1.15); these respondents were more likely to be younger, male, have less than 12 years of education, identify as Aboriginal and/or Torres Strait Islander Peoples, speak a language other than English at home and have no cardiovascular risk factors. CONCLUSION: Awareness of heart attack symptoms has decreased in the years since the Warning Signs campaign in Australia, with 1 in 5 adults currently unable to name a single heart attack symptom. New approaches are needed to promote and sustain this knowledge, and to ensure people act appropriately and promptly if symptoms occur.

Long-Term Valve Durability in Patients Undergoing Transcatheter Aortic Valve Implantation.

AIMS: To evaluate the long-term incidence of structural valve deterioration (SVD) in patients who underwent transcatheter aortic valve implantation (TAVI). METHOD AND RESULTS: Between 2008 and 2018, 693 underwent TAVI at two centres. Four hundred and twenty-one (421) patients (mean age 83.6±6.0 yrs) survived for ≥2 years post TAVI and had at least two consecutive transthoracic echocardiographies (TTEs) with the latest TTE no less than 2 years after TAVI, and were therefore included in the analysis for SVD. Median follow-up was 4.7 (3.6-6.0) years and median echocardiography follow-up 3 (3.0-4.0) years. All-cause mortality was 30.9% (130) with a median time to death of 4.1 (3.0-5.6) years. The cumulative incidence of SVD increased from 1.7% (95% CI, 0.4-2.9) at 3 years to 3.5% (95% CI, 1.5-5.8) at 5 years and 4.7% (95% CI, 1.6-7.9) at 10 years. The overall median time to SVD was 3 (2-4) years. Twelve (12) patients demonstrated SVD stage 2, and 1 patient stage 3. No SVD required re-intervention. All other patients showed no significant changes in valve parameters over time. CONCLUSIONS: Structural valve deterioration is an uncommon event, occurring in 5% over a total follow-up of 10 years. Most patients show stable valve parameters. However, the analysis is limited by the loss of follow-up (owing to patient mortality), which renders extrapolation of the data to a younger patient population difficult.

Variation in Health Care Processes, Quality and Outcomes According to Day and Time of Chest Pain Presentation via Ambulance.

BACKGROUND: Previous studies examining temporal variations in cardiovascular care have largely been limited to assessing weekend and after-hours effects. We aimed to determine whether more complex temporal variation patterns might exist in chest pain care. METHODS: This was a population-based study of consecutive adult patients attended by emergency medical services (EMS) for non-traumatic chest pain without ST elevation in Victoria, Australia between 1 January 2015 and 30 June 2019. Multivariable models were used to assess whether time of day and week stratified into 168 hourly time periods was associated with care processes and outcomes. RESULTS: There were 196,365 EMS chest pain attendances; mean age 62.4 years (standard deviation [SD] 18.3) and 51% females. Presentations demonstrated a diurnal pattern, a Monday-Sunday gradient (Monday peak) and a reverse weekend effect (lower rates on weekends). Five temporal patterns were observed for care quality and process measures, including a diurnal pattern (longer emergency department [ED] length of stay), an after-hours pattern (lower angiography or transfer for myocardial infarction, pre-hospital aspirin administration), a weekend effect (shorter ED clinician review, shorter EMS off-load time), an afternoon/evening peak period pattern (longer ED clinician review, longer EMS off-load time) and a Monday-Sunday gradient (ED clinician review, EMS offload time). Risk of 30-day mortality was associated with weekend presentation (Odds ratio [OR] 1.15, p=0.001) and morning presentation (OR 1.17, p<0.001) while risk of 30-day EMS reattendance was associated with peak period (OR 1.16, p<0.001) and weekend presentation (OR 1.07, p<0.001). CONCLUSIONS: Chest pain care demonstrates complex temporal variation beyond the already established weekend and after-hours effect. Such relationships should be considered during resource allocation and quality improvement programs to improve care across all days and times of the week.