Protocol Variation in Functional Coronary Angiography Among Patients With Suspected Angina With Non-Obstructive Coronary Arteries: A Nationwide Snapshot of Current Practice Within Australia and New Zealand.

BACKGROUND: Functional coronary angiography (FCA) for endotype characterisation (vasospastic angina [VSA], coronary microvascular disease [CMD], or mixed) is recommended among patients with angina with non-obstructive coronary arteries. Whilst clear diagnostic criteria for VSA and CMD exist, there is no standardised FCA protocol. Variations in testing protocol may limit the widespread uptake of testing, generalisability of results, and expansion of collaborative research. At present, there are no data describing protocol variation across an entire geographic region. Therefore, we aimed to capture current practice variations in the approach to FCA to improve access and standardisation for diagnosis of coronary vasomotor disorders in Australia and New Zealand. METHOD: Between July 2022 and July 2023, we conducted a national survey across all centres in Australia and New Zealand with an active FCA program. The survey captured attitudes towards FCA and protocols used for diagnosis of coronary vasomotor disorders at 33 hospitals across Australia and New Zealand. RESULTS: Survey responses were received from 39 clinicians from 33 centres, with representation from centres within all Australian states and territories and both North and South Islands of New Zealand. A total of 21 centres were identified as having an active FCA program. In general, respondents agreed that comprehensive physiology testing helped inform clinical management. Barriers to program expansion included cost, additional catheter laboratory time, and the absence of an agreed-upon national protocol. Across the clinical sites, there were significant variations in testing protocol, including the technique used (Doppler vs thermodilution), order of testing (hyperaemia resistance indices first vs vasomotor function testing first), rate and dose of acetylcholine administration, routine use of temporary pacing wire, and routine single vs multivessel testing. Overall, testing was performed relatively infrequently, with very little follow-on FCA performed, despite nearly all respondents believing this would be clinically useful. CONCLUSIONS: This survey demonstrates, for the first time, variations in FCA protocol among testing centres across two entire countries. Furthermore, whilst FCA was deemed clinically important, testing was performed relatively infrequently with little or no follow-on testing. Development and adoption of a standardised national FCA protocol may help improve patient access to testing and facilitate further collaborative research within Australia and New Zealand.

Sex Differences in Incidence and Outcome of Out-of-Hospital Cardiac Arrest Within a Local Health Network.

Introduction: Sex and gender differences in presentation and characteristics of out-of-hospital cardiac arrest (OHCA) are established in cohorts with presumed cardiac aetiology but not non-cardiac etiology. This study investigated the effect of sex on incidence and outcome of OHCA according to presumed and adjudicated aetiology within a local health network. Methods: Population-based observational cohort study of emergency medical services (EMS) attended OHCAs within an Australian local health network. Cases identified from an EMS registry between 2012-2016 were linked to a hospital registry. Age-standardised incidence and baseline characteristics were stratified by sex for EMS-treated OHCA, non-EMS witnessed presumed cardiac and obvious non-cardiac sub-cohorts, and hospitalised cases. Logistic regression was used to explore the primary outcome of survival to hospital discharge. Results: We identified 2,024 EMS-attended and 780 EMS-treated OHCAs. The non-EMS witnessed sub-cohorts comprised 504 presumed cardiac and 168 obvious non-cardiac OHCAs. Adjudicated aetiology was recorded in 123 hospitalised cases. Age-standardised incidence for women was almost half that of men across all groups. Across cohorts, women were generally older and arrested with a non-shockable initial rhythm in an area of low socioeconomic status. There was no sex difference in the primary outcome for the main EMS-treated cohort or in the non-cardiac sub-cohorts. The sex difference in outcome in the presumed cardiac sub-cohort was not present after multivariable adjustment. Conclusions: There are sex differences in incidence and outcome of EMS-treated OHCA that appear to be driven by differences in susceptibility to cardiac arrhythmias and underlying etiology, rather than treatment delays or disparities.

In-hospital mode of death after out-of-hospital cardiac arrest.

Introduction: Factors associated with in-hospital mortality after out-of-hospital cardiac arrest (OHCA), such as mode of death and withdrawal of life-sustaining treatment (WLST), are not well established. This study aimed to compare clinical characteristics, timing of WLST and death, and precipitating aetiology between modes of death for OHCAs treated at hospital within a local health network. Methods: Retrospective cohort study of adult non-traumatic OHCAs included in a hospital based OHCA registry between 2011 and 2016 and deceased at hospital discharge, excluding cases retrieved to external hospitals. Mode of death was defined as (1) cardiovascular instability, (2) non-neurological WLST, (3) neurological WLST, and (4) formal brain death. Relevant data were extracted from the registry and stratified according to mode of death and timing of death as early (within the emergency department) or late (after admission). Results: Mode of death data was available for 69 early and 144 late deaths. Cardiovascular instability was the primary mode for 75% of early deaths, while 72% of late deaths were attributed to neurological injury (47% neurological WLST and 24% brain death, combined). Cardiovascular instability was associated with cardiac aetiology, brain death was associated with younger age and highest rates of organ donation, and neurological WLST was associated with highest rates of targeted temperature management, and longest time from arrest to death (p < 0.05). Conclusions: This is the first study to compare clinical characteristics of adult patients resuscitated from OHCA according to in-hospital mode of death. A consensus on the definition of mode of death with standardised classification is needed.

Prevalence and real-world management of NSTEMI with multivessel disease.

Background: Non-ST elevation myocardial infarction (NSTEMI) has higher post-discharge mortality than ST-elevation myocardial infarction (STEMI). Prognosis worsens in those with multivessel coronary disease (MVD). However, information about the prevalence and extent of MVD in NSTEMI is limited, in turn limiting insights into optimal treatment strategies. This study aimed to define the prevalence and extent of MVD, preferred treatment strategies and the predictors of MVD in a real-world NSTEMI population. Methods: The Coronary Angiogram Database of South Australia (CADOSA) was used to identify consecutive patients presenting to major teaching hospitals with NSTEMI between 2012 and 2016. Obtaining clinical and angiographic details, patients were stratified by the number of significantly diseased vessels (0,1,2,3-VD), defined by a stenosis of ≥70%, or ≥50% in the left main coronary artery. Data was analysed retrospectively. Results: The prevalence of MVD (2- or 3-VD) was 42% amongst 3,722 NSTEMI presentations. Multivariate logistic regression modelling showed age, male gender, diabetes, dyslipidaemia and prior myocardial infarction predicted MVD over 1-VD or 0-VD. Percutaneous coronary intervention (PCI) was performed in 42% of patients with MVD. This comprised 61% of 2-VD patients and only 22% of 3-VD patients, with 24% and 66% of each group referred for coronary bypass grafting, respectively. Among MVD patients treated with PCI, 76% had their culprit lesion treated alone in the index admission. Conclusions: In this NSTEMI cohort, over 40% had MVD. Notably, a minority of patients with MVD undergoing PCI received multivessel revascularisation. This real-world practice emphasises that further evaluation is required to determine whether complete revascularisation is beneficial in NSTEMI, as reported for STEMI.

Management of ischaemia with non-obstructive coronary arteries (INOCA).

Up to half of patients undergoing elective coronary angiography for the investigation of chest pain do not present with evidence of obstructive coronary artery disease. These patients are often discharged with a diagnosis of non-cardiac chest pain, yet many could have an ischaemic basis for their symptoms. This type of ischaemic chest pain in the absence of obstructive coronary artery disease is referred to as INOCA (ischaemia with non-obstructive coronary arteries). This comprehensive review of INOCA management looks at why these patients require treatment, who requires treatment based on diagnostic evaluation, what clinical treatment targets should be considered, how to treat patients using a personalised medicine approach, when to initiate treatment, and where future research is progressing.

Overcoming challenges of establishing a hospital-based out-of-hospital cardiac arrest registry: accuracy of case identification using administrative data and clinical registries.

INTRODUCTION: Comprehensive identification of out-of-hospital cardiac arrest (OHCA) cases for inclusion in registries remains challenging due to the inherent diversity of OHCA aetiology, presentation, and management. The Northern Adelaide Local Health Network (NALHN) OHCA registry identifies OHCAs presenting to NALHN hospitals using existing data sources to monitor in-hospital treatment and survival. This study aimed to investigate the accuracy of hospital-based data sources for identifying OHCA cases treated at hospital. METHODS: Retrospective analysis of all OHCAs aged >18 years included in the NALHN OHCA registry between 2011-16. Registry cases are identified from an emergency medical service (EMS) OHCA registry, Emergency Department (ED) and ICD-10 coding datasets, and key-word searches of two in-hospital clinical registries. Sensitivity and positive predictive values (PPV) of each hospital-based data source were analysed with respect to (a) the number of cases expected to be identified by that source, (b) total OHCA. Non-OHCAs yielded by each source were explored and a sub-analysis of ICD-10 codes was performed. RESULTS: Between 2011-16, the four hospital-based sources yielded 992 cases, of which 383 were confirmed as OHCA. The ED coding dataset was the most accurate with a sensitivity and PPV of 78%. The ICD-10 coding dataset had good sensitivity but low PPV (33%). The ED coding dataset, combined with the two in-hospital clinical registries, identified 93% of OHCAs. CONCLUSIONS: No single dataset identified all OHCAs presenting to NALHN hospitals. Combined hospital-based data sources provide a valid method of identifying OHCAs treated at hospital that may be adapted to augment EMS-based data.

Cardiologists appropriately exclude resuscitated out-of-hospital cardiac arrests from emergency coronary angiography.

OBJECTIVE: Emergency coronary angiography after resuscitated out-of-hospital cardiac arrest as a selective or non-selective diagnostic procedure with or without intervention continues to be the subject of debate. This study sought to determine if cardiologists reliably select patients using clinical judgement for emergency coronary angiography without missing acutely ischemic cases requiring revascularization. METHODS: Presenting clinical details and ECGs (within 2 hours) from 52 consecutive out-of-hospital cardiac arrest patients who underwent non-selective coronary angiography were compiled retrospectively. Three out-of-hospital cardiac arrest-experienced interventional cardiologists, blinded to patient outcome, independently determined working diagnosis, and decision for emergency coronary angiography using clinical judgement. Sensitivity of the cardiologists' decision was assessed with respect to the outcome of acute revascularization. Inter-rater differences, consensus in clinical assessment, and influence of working diagnosis were also investigated. RESULTS: Sensitivity of individual cardiologist's decision for emergency coronary angiography with respect to acute revascularization was very high (adjusted overall sensitivity = 95.8%, 95% CI = 89-100, cardiologist range = 93%-100%), and perfect for the consensus of 2 or more cardiologists (100%, 95% CI = 79.4-100). There was no statistical difference in the sensitivity of this decision between cardiologists (P < 0.05), and inter-rater agreement was moderate (78% overall agreement, Κ = 0.56). CONCLUSIONS: Experienced cardiologists recommend emergency coronary angiography in all resuscitated out-of-hospital cardiac arrest requiring acute revascularization and appropriately excluded one-third of patients. Rather than advocating a non-selective, or conversely, a restrictive strategy with respect to coronary angiography after out-of-hospital cardiac arrest, the findings support an individualized approach by a multidisciplinary emergency team that includes experienced cardiologists. The results should be confirmed in a larger prospective study.

Out-of-hospital cardiac arrest-review of demographics in South Australia to inform decisions about the provision of automatic external defibrillators within the community.

INTRODUCTION: Sudden, out-of-hospital cardiac arrest (OHCA) has an annual incidence of approximately 50 per 100,000 population. Public access defibrillation is seen as one of the key strategies in the chain-of-survival for OHCA. Positioning of these devices is important for the maximization of public health outcomes. The literature strongly advocates widespread public access to automated external defibrillatiors (AEDs). The most efficient placement of AEDs within individual communities remains unclear. METHODS: A retrospective case review of OHCAs attended by the South Australia Ambulance Service in metropolitan and rural South Australia over a 30-month period was performed. Data were analyzed using Utstein-type indicators. Detailed demographics, summative data, and clinical data were recorded. RESULTS: A total of 1,305 cases of cardiac arrest were reviewed. The annual rate of OHCA was 35 per 100,000 population. Of the cases, the mean value for the ages was 66.3 years, 517 (39.6%) were transported to hospital, 761 (58.3%) were judged by the paramedic to be cardiac, and 838 (64.2%) were witnessed. Bystander cardiopulmonary resuscitation (CPR) was performed in 495 (37.9%) of cases. The rhythm on arrival was ventricular fibrillation (VF) or ventricular tachycardia (VT) in 419 (32.1%) cases, and 315 (24.1%) of all arrests had return of spontaneous circulation (ROSC) before or on arrival at the hospital. For cardiac arrest cases that were witnessed by the ambulance service (n=121), the incidence of ROSC was 47.1%. During the 30-month period, there only was one location that recorded more than one cardiac arrest. No other location recorded recurrent episodes. CONCLUSIONS: This study did not identify any specific location that would justify defibrillator placement over any other location without an existing defibrillator. The impact of bystander CPR and the relatively low rate of bystander CPR in this study points to an area of need. The relative potential impact of increasing bystander CPR rates versus investing in defibrillators in the community is worthy of further consideration.

Improving cardiovascular care for indigenous populations.

The challenges and opportunities for provision of, and access to, reliable chronic cardiovascular health care for Indigenous people were addressed by expert speakers from New Zealand and Australia. It is well recognised that cardiovascular disease is a life-long concern, requiring reliable follow-up, early transition of clinical research into practice and ongoing support of patients. The clinical outcomes and long-term prognosis of individuals with cardiovascular disease are critically dependent upon the quality and availability of follow-up and chronic care facilities. This paper summarises the principal issues identified by the expert speakers for the provision of chronic cardiovascular health care to Indigenous peoples in Australia and New Zealand; identifies common challenges and describes important initiatives which the Cardiac Society of Australia and New Zealand (CSANZ), in partnership with health care professionals, communities and governments, can undertake in order to achieve the goals of uniform and equitable health care for chronic cardiovascular disease in all the Indigenous peoples, relevant to the needs of these peoples, in New Zealand and Australia. The issues addressed by the meeting include: 1) Determination of appropriate models for effective delivery of cardiovascular health care. (2) Who should deliver cardiovascular health care and what are the workforce requirements. (3) What support systems and infrastructure are required. (4) How can primary care and secondary specialist services be effectively integrated.

Rheumatic heart disease in indigenous populations.

Rates of acute rheumatic fever and chronic rheumatic heart disease in Aboriginal people, Torres Strait Islanders and Maori continue to be unacceptably high. The impact of rheumatic heart disease is inequitable on these populations as compared with other Australians and New Zealanders. The associated cardiac morbidity, including the development of rheumatic valve disease, and cardiomyopathy, with possible sequelae of heart failure, development of atrial fibrillation, systemic embolism, transient ischaemic attacks, strokes, endocarditis, the need for interventions including cardiac surgery, and impaired quality of life, and shortened life expectancy, has major implications for the individual. The adverse health and social effects may significantly limit education and employment opportunities and increase dependency on welfare. Additionally there may be major adverse impacts on family and community life. The costs in financial terms and missed opportunities, including wasted young lives, are substantial. Prevention of acute rheumatic fever is dependent on the timely diagnosis and treatment of sore throats and skin infections in high-risk groups. Both Australia and New Zealand have registries for acute rheumatic fever but paradoxically neither includes all cases of chronic rheumatic heart disease many of whom would benefit from close surveillance and follow-up. In New Zealand and some Australian States there are programs to give secondary prophylaxis with penicillin, but these are not universal. Surgical outcomes for patients with rheumatic valvular disease are better for valve repair than for valve replacement. Special attention to the selection of the appropriate valve surgery and valve choice is required in pregnant women. It may be necessary to have designated surgical units managing Indigenous patients to ensure high rates of surgical repair rather than valve replacement. Surgical guidelines may be helpful. Long-term follow-up of the outcomes of surgery in Indigenous patients with rheumatic heart disease is required. Underpinning these strategies is the need to improve poverty, housing, education and employment. Cultural empathy with mutual trust and respect is essential. Involvement of Indigenous people in decision making, design, and implementation of primary and secondary prevention programs, is mandatory to reduce the unacceptably high rates of rheumatic heart disease.

Overview and determinants of cardiovascular disease in indigenous populations.

Cardiovascular disease (CV) is an important problem among the 400 million Indigenous Populations around the world, and has been included in the World Health Organization (WHO) "2008-2013 Action Plan for Non-Communicable Diseases". Our understanding of the causes of CV disease in the Indigenous populations of Australia and New Zealand will be facilitated by better understanding the causes of CV disease in Indigenous populations around the world. The opening scientific presentations of the Inaugural CSANZ Conference on Indigenous Cardiovascular Health were from two international speakers notable for their commitment to Indigenous Health as a global problem.

Indigenous vascular health-bridging the survival gap: strategies for community-based services.

The vascular health of Indigenous Australians requires urgent first aid. In concert with improved primary health care strategies, there is a need for improved access to both specialist and tertiary vascular health services. More importantly, these services must be strongly integrated to allow seemless transition in a patient focussed model of care that simultaneously addresses the need for community-based services and transition to frequently remote tertiary facilities. Education and empowerment of local health workers to identify patients requiring primary or secondary prevention and deliver evidence based therapies is as important as the need to evaluate the impact of services on disease burden. It is pivotal to the success of expanded services that clinical support is delivered in conjunction with educational and research programs.

Practical solutions for injury surveillance at mass gatherings.

INTRODUCTION: Public safety at mass gatherings is the responsibility of multiple agencies. Injury surveillance and inter-agency communication are pivotal to ensure continued public safety. OBJECTIVES: The principal objective of this pilot study was to improve the identification of trends and patterns of injury presentations at mass gatherings. This was achieved through an electronic process for data gathering to support timely reporting of injury data. In addition, what evolved was the development of an inter-agency communication model to support information transfer. METHODS: An Electronic Injury Surveillance System was created and piloted at two mass gatherings in South Australia. Live, real-time data were collected via customized software supported by electronic report generation. RESULTS: The Injury Surveillance System captured data on 181 injured patients and assisted in the identification of trends and patterns of presentations. The relevant injuries and patterns of injuries were reported to the appropriate organizations based on pre-defined communication models. CONCLUSIONS: The pilot study demonstrated that it was possible to perform "live", portable injury surveillance during patient presentations at two mass gatherings. The Injury Surveillance System ensured immediate data capture. Well-defined communication systems established for this pilot also enabled early action to rectify hazards. Further development of electronic injury surveillance should be considered as an essential tool for managing public safety at mass gatherings.

Forecasting medical work at mass-gathering events: predictive model versus retrospective review.

INTRODUCTION: Mass-gathering events are dynamic and challenge traditional medical management systems. To improve the system for the provision of first aid at mass-gathering events, an evaluation of two models that assist in forecasting the number of patients presenting for first-aid services was conducted. METHOD: A prospective evaluation of a recurrent, mass-gathering event was undertaken comparing predicted patient presentations and ambulance transfers generated by a predictive model developed by Arbon et al and a retrospective review of seven years of historical, event data as described by Zeitz et al. RESULTS: Patient presentation rate (per 1,000 patrons) for this event was 1.6 and the transport to hospital rate (per 1,000 patrons) was 0.07. The retrospective review closely predicted the actual overall attendance. Both methods forecast the number of patients presenting on a daily basis. The prediction proved to be more accurate, on a day-by-day basis, using the Zeitz method. CONCLUSION: The Arbon method is particularly useful for events where there is no or limited information about previous medical work. Retrospective review of data generated from specific events (Zeitz method) considers the unique and individual variability that can occur from event to event and is more accurate at predicting patient presentations when the data are available. Both methods have the potential to be used more frequently to adequately and efficiently plan for the resources required for specific events.