Tandem lesions associate with angiographic progression of coronary artery stenoses.

Background: Although the clinical factors associated with progression of coronary artery disease have been well studied, the angiographic predictors are less defined. Objectives: Our objective was to study the clinical and angiographic factors that associate with progression of coronary artery stenoses. Methods: We conducted a retrospective analysis of consecutive patients undergoing multiple, clinically indicated invasive coronary angiograms with an interval greater than 6 months, between January 2013 and December 2016. Lesion segments were analysed using Quantitative Coronary Angiography (QCA) if a stenosis ≥ 20 % was identified on either angiogram. Stenosis progression was defined as an increase ≥ 10 % in stenosis severity, with progressor groups analysed on both patient and lesion levels. Mixed-effects regression analyses were performed to evaluate factors associated with progression of individual stenoses. Results: 199 patients were included with 881 lesions analysed. 108 (54.3 %) patients and 186 (21.1 %) stenoses were classified as progressors. The median age was 65 years (IQR 56-73) and the median interval between angiograms was 2.1 years (IQR 1.2-3.0). On a patient level, age, number of lesions and presence of multivessel disease at baseline were each associated with progressor status. On a lesion level, presence of a stenosis downstream (OR 3.07, 95 % CI 2.04-4.63, p < 0.001) and circumflex artery stenosis location (OR 1.81, 95 % CI 1.21-2.7, p = 0.004) were associated with progressor status. Other lesion characteristics did not significantly impact progressor status or change in stenosis severity. Conclusion: Coronary lesions which have a downstream stenosis may be at increased risk of stenosis progression. Further research into the mechanistic basis of this finding is required, along with its implications for plaque vulnerability and clinical outcomes.

Anti-Anginal Efficacy of Zibotentan in the Coronary Slow-Flow Phenomenon.

BACKGROUND: Patients with coronary microvascular disorders often experience recurrent angina for which there are limited evidence-based therapies. These patients have been found to exhibit increased plasma levels of endothelin; thus, selective endothelin-A (Et-A) receptor blockers such as zibotentan may be an effective anti-anginal therapy in these patients. The study evaluated the impact of a 10 mg daily dose of zibotentan on spontaneous angina episodes in patients with the coronary slow-flow phenomenon who had refractory angina (i.e., experiencing angina at least three times/week despite current anti-anginal therapy). METHODS: Using a randomized, double-blind, placebo-controlled, crossover trial design with 4-week treatment periods, 18 patients (63.2 ± 9.9 years, 33% females) were recruited. The primary endpoint was angina frequency as measured by an angina diary, with secondary endpoints including nitrate consumption, angina duration/severity and the Seattle Angina Questionnaire (SAQ) domains. RESULTS: During the 4 weeks of therapy, angina frequency significantly improved with zibotentan therapy (placebo 41.4 (58.5) vs. zibotentan 29.2 (31.6), p < 0.05), and sublingual nitrate consumption significantly reduced (placebo 11.8 (15.2) vs. zibotentan 8.8 (12.9), p < 0.05. CONCLUSIONS: Zibotentan improved the frequency of spontaneous angina episodes and reduced sublingual nitrate consumption in patients unresponsive to standard anti-anginal therapy.

Clinical Effectiveness and Utilisation of Cardiac Rehabilitation After Hospital Discharge: Data Linkage Analysis of 84,064 Eligible Discharged Patients (2016-2021).

BACKGROUND: Despite the highest levels of evidence on cardiac rehabilitation (CR) effectiveness, its translation into practice is compromised by low participation. AIM: This study aimed to investigate CR utilisation and effectiveness in South Australia. METHODS: This retrospective cohort study used data linkage of clinical and administrative databases from 2016 to 2021 to assess the association between CR utilisation (no CR received, commenced without completing, or completed) and the composite primary outcome (mortality/cardiovascular re-admissions within 12 months after discharge). Cox survival models were adjusted for sociodemographic and clinical data and applied to a population balanced by inverse probability weighting. Associations with non-completion were assessed by logistic regression. RESULTS: Among 84,064 eligible participants, 74,189 did not receive CR, with 26,833 of the 84,064 (31.9%) participants referred. Of these, 9,875 (36.8%) commenced CR, and 7,681 of the 9,875 (77.8%) completed CR. Median waiting time from discharge to commencement was 40 days (interquartile range, 23-79 days). Female sex (odds ratio [OR] 1.12; 95% CI 1.01-1.24; p=0.024), depression (OR 1.17; 95% CI 1.05-1.30; p=0.002), and waiting time >28 days (OR 1.15; 95% CI 1.05-1.26; p=0.005) were associated with higher odds of non-completion, whereas enrolment in a telehealth program (OR 0.35; 95% CI 0.31-0.40; p<0.001) was associated with lower odds of non-completion. Completing CR (hazard ratio [HR] 0.62; 95% CI 0.58-0.66; p<0.001) was associated with a lower risk of 12-month mortality/cardiovascular re-admissions. Commencing without completing was also associated with decreased risk (HR 0.81; 95% CI 0.73-0.90; p<0.001), but the effect was lower than for those completing CR (p<0.001). CONCLUSIONS: Cardiac rehabilitation (CR) attendance is associated with lower all-cause mortality/cardiovascular re-admissions, with CR completion leading to additional benefits. Quality improvement initiatives should include promoting referral, women's participation, access to telehealth, and reduction of waiting times to increase completion.

Modifiable and Non-Modifiable Risk Factors for Premature Coronary Heart Disease (PCHD): Systematic Review and Meta-Analysis.

AIM: We aimed to compare the prevalence of modifiable and non-modifiable coronary heart disease (CHD) risk factors among those with premature CHD and healthy individuals. METHODS: PubMed, CINAHL, Embase, and Web of Science databases were searched (review protocol is registered in PROSPERO CRD42020173216). The quality of studies was assessed using the National Heart, Lung and Blood Institute tool for cross-sectional, cohort and case-control studies. Meta-analyses were performed using Review Manager 5.3. Effect sizes for categorical and continuous variables, odds ratio (OR) and mean differences (MD)/standardised mean differences (SMD) with 95% confidence intervals (CI) were reported. RESULTS: A total of n=208 primary studies were included in this review. Individuals presenting with premature CHD (PCHD, age ≤65 years) had higher mean body mass index (MD 0.54 kg/m2, 95% CI 0.24, 0.83), total cholesterol (SMD 0.27, 95% CI 0.17, 0.38), triglycerides (SMD 0.50, 95% CI 0.41, 0.60) and lower high-density lipoprotein cholesterol (SMD 0.79, 95% CI: -0.91, -0.68) compared with healthy individuals. Individuals presenting with PCHD were more likely to be smokers (OR 2.88, 95% CI 2.51, 3.31), consumed excessive alcohol (OR 1.40, 95% CI 1.05, 1.86), had higher mean lipoprotein (a) levels (SMD 0.41, 95% CI 0.28, 0.54), and had a positive family history of CHD (OR 3.65, 95% CI 2.87, 4.66) compared with healthy individuals. Also, they were more likely to be obese (OR 1.59, 95% CI 1.32, 1.91), and to have had dyslipidaemia (OR 2.74, 95% CI 2.18, 3.45), hypertension (OR 2.80, 95% CI 2.28, 3.45), and type 2 diabetes mellitus (OR 2.93, 95% CI 2.50, 3.45) compared with healthy individuals. CONCLUSION: This meta-analysis confirms current knowledge of risk factors for PCHD, and identifying these early may reduce CHD in young adults.

Influence of Socioeconomic Status on the Association Between Pregnancy Complications and Premature Coronary Artery Disease: Linking Three Cohorts.

Background: We hypothesized that there is an influence of socioeconomic status (SES) on association between pregnancy complications and premature coronary artery disease (PCAD) risk. Materials and Methods: This project involved a data linkage approach merging three databases of South Australian cohorts using retrospective, age-matched case-control study design. Cases (n = 721), that is, women aged <60 years from Coronary Angiogram Database of South Australia (CADOSA) were linked to South Australian Perinatal Statistics Collection (SAPSC) to ascertain prior pregnancy outcomes and SES. Controls (n = 194) were selected from North West Adelaide Health Study (NWAHS), comprising women who were healthy or had health conditions unrelated to CAD, age matched to CADOSA (±5 years), and linked to SAPSC to determine prior pregnancy outcomes and SES. This project performed comparative analysis of SES using socioeconomic indexes for areas-index of relative socioeconomic advantage and disadvantage (SEIFA-IRSAD) scores across three databases. Results: Findings revealed that SEIFA-IRSAD scores at the time of pregnancy (p-value = 0.005) and increase in SEIFA-IRSAD scores over time (p-value = 0.040) were significantly associated with PCAD. In addition, when models were adjusted for SEIFA-IRSAD scores at the time of pregnancy and age, risk factors including placenta-mediated pregnancy complications such as preterm birth (odds ratio [OR] = 4.77, 95% confidence interval [CI]: 1.74-13.03) and history of a miscarriage (OR = 2.14, 95% CI: 1.02-4.49), and cardiovascular disease (CVD) risk factors including smoking (OR = 8.60, 95% CI: 3.25-22.75) were significantly associated with PCAD. When the model was adjusted for change in SEIFA-IRSAD scores (from CADOSA/NWAHS to SAPSC) and age, pregnancy-mediated pregnancy complications including preterm birth (OR = 4.40, 95% CI: 1.61-12.05) and history of a miscarriage (OR = 2.09, 95% CI: 1.00-4.35), and CVD risk factor smoking (OR = 8.75, 95% CI: 3.32-23.07) were significantly associated with PCAD. Conclusion: SES at the time of pregnancy and change in SES were not associated with PCAD risk.

Sex-specific and ethnicity-specific differences in MINOCA.

Suspected myocardial infarction with non-obstructive coronary arteries (MINOCA) has received increasing attention over the past decade. Given the heterogeneity in the mechanisms underlying acute myocardial infarction in the absence of obstructive coronary arteries, the syndrome of MINOCA is considered a working diagnosis that requires further investigation after diagnostic angiography studies have been performed, including coronary magnetic resonance angiography and functional angiography. Although once considered an infrequent and low-risk form of myocardial infarction, recent data have shown that the prognosis of MINOCA is not as benign as previously assumed. However, despite increasing awareness of the condition, many questions remain regarding the diagnosis, risk stratification and treatment of MINOCA. Women seem to be more susceptible to MINOCA, but studies on the sex-specific differences of the disease are scarce. Similarly, ethnicity-specific factors might explain discrepancies in the observed prevalence or underlying pathophysiological mechanisms of MINOCA but data are also scarce. Therefore, in this Review, we provide an update on the latest evidence available on the sex-specific and ethnicity-specific differences in the clinical features, pathophysiological mechanisms, treatment and prognosis of MINOCA.

Angina and Non-Obstructive Coronary Artery (ANOCA) Patients with Coronary Vasomotor Disorders.

Angina and Non-Obstructive Coronary Artery (ANOCA) patients often lack a clear explanation for their symptoms, and are frequently discharged with the label of "unspecified chest pain", despite the availability of functional coronary angiography (provocative spasm and microvascular function testing) to identify potential underlying coronary vasomotor disorders. This study compared the outcomes of ANOCA patients with a coronary vasomotor disorder diagnosis post elective coronary angiography to patients discharged with unspecified chest pain. Using the CADOSA (Coronary Angiogram Database of South Australia) registry, consecutive symptomatic patients (n = 7555) from 2012 to 2018 underwent elective angiography; 30% had ANOCA (stenosis <50%). Of this cohort, 9% had documented coronary vasomotor disorders diagnosed, and 91% had unspecified chest pain. Patients with coronary vasomotor disorders were younger and had a similar female prevalence compared with those with unspecified chest pain. New prescriptions of calcium channel blockers and long-acting nitrates were more common for the coronary vasomotor cohort at discharge. In the 3 years following angiography, both groups had similar all-cause mortality rates. However, those with coronary vasomotor disorders had higher rates of emergency department visits for chest pain (39% vs. 15%, p < 0.001) and readmissions for chest pain (30% vs. 10%, p < 0.001) compared with those with unspecified chest pain. This real-world study emphasizes the importance of identifying high-risk ANOCA patients for personalized management to effectively address their symptoms.

Pregnancy Complications Are Associated with Premature Coronary Artery Disease: Linking Three Cohorts.

Background: There is increasing evidence that women who experience placenta-mediated pregnancy complications and gestational diabetes mellitus (GDM) are at higher risk for the development of coronary artery disease (CAD) later in life. We hypothesized that there is an association between placenta-mediated pregnancy complications, GDM, and risk of premature CAD (PCAD). Methods: This research project involved a data linkage approach merging three databases of South Australian cohorts by using a retrospective, age-matched case-control study design. Cases (n = 721) were ascertained from the Coronary Angiogram Database of South Australia (CADOSA). Women <60 years from CADOSA were linked to South Australian Perinatal Statistics Collection (SAPSC) to ascertain their prior pregnancy outcomes. Controls (n = 194) were selected from North West Adelaide Health Study (NWAHS) and comprised women who were healthy or had other health conditions unrelated to CAD, age-matched to CADOSA (±5 years), and linked to SAPSC to determine their pregnancy outcomes. PCAD was defined as >50% stenosis in one or more coronary arteries at coronary angiography. Results: Compared with women without a history of PCAD, women who were diagnosed with PCAD were more likely to have experienced the placenta-mediated pregnancy complications of preterm birth (adjusted odds ratio [OR] = 2.46, 95% confidence interval [CI]: 1.21-5.00) or low-birth weight (adjusted OR = 2.44, 95% CI: 1.22-4.88), or have been diagnosed with active asthma during pregnancy (adjusted OR = 3.52, 95% CI: 1.05-11.76). Conclusion: Placenta-mediated pregnancy complications should be recognized as clear risk markers for future PCAD.

Temporal trends in percutaneous coronary intervention in Australia: A retrospective analysis from 2000-2021.

OBJECTIVE: The aim of this study was to describe the trend in percutaneous coronary intervention (PCI) with insertion of a stent in Australia from 2000/01 to 2020/21 and investigate trends in same-day versus non-same-day discharge following PCI. A secondary aim was to compare the rate of coronary artery bypass grafting (CABG) with PCI procedures, while a third aim was to compare marked PCI trend changes with the PCI guidelines during the study period. BACKGROUND: PCI with stent deployment is the most common form of interventional treatment for coronary artery disease, and its use has been expanding since 2000. However, there is a lack of descriptive studies of the national trend in Australia. METHODS: All procedures for PCI and CABG were extracted across 21 years (2000/01 to 2020/21) from the Australian Institute of Health and Welfare data. Age-standardized rates were calculated using the Australian standard population as of June 2001. The ratio of PCI to CABG procedures was also calculated. Trends for PCI were stratified by age, gender, and same-day or overnight discharge episodes. Linear regression analysis was done to compare the age-standardized rates across different age categories. Segmented regression analysis was performed to ascertain the change in the age-standardized rates of PCI during the study period. Whether the changepoints in the trend were matched with guideline updates was also assessed. RESULTS: There were 751 728 PCI procedures in persons aged 30 years and above between 2000/01 and 2020/21. The age-standardized rate for the study period showed that persons aged 60-74 years had a higher rate of procedures (102.7) compared to persons aged 30-59 years (81.3) and 75 years and older (61.8) (P < 0.001). There were two statistically significant changepoints in the overall trend; 2005/06 and 2013/14, matched with the change in PCI guidelines. Despite the lower number of procedures for same-day discharge episodes, there has been an increasing trend since 2014/15. More than two-thirds of all stenting procedures were the insertion of a single stent. PCI to CABG procedure ratio increased from 0.6 in 2000/01 to 1.8 in 2020/21. CONCLUSIONS: There was a varying trend in the age-standardized rate of PCI with a peak in 2005/06. The trend appears to be stabilizing in the later part of the study period, but the rate for same-day discharge episodes showed an increasing trend after 2014/15. There is consistency with changepoints in the trend and updated PCI guideline recommendations. The ratio of PCI with insertion of a stent to CABG procedure increased substantially across the study period.

Risk Factors for Early-Onset Versus Late-Onset Coronary Heart Disease (CHD): Systematic Review and Meta-Analysis.

AIM: We aimed to systematically compare literature on prevalence of modifiable and non-modifiable risk factors for early compared to late-onset coronary heart disease (CHD). METHODS: PubMed, CINAHL, Embase, and Web of Science databases were searched (review protocol registered in PROSPERO CRD42020173216). Study quality was assessed using the National Heart, Lung and Blood Institute tool for observational and case-control studies. Review Manager 5.3 was used for meta-analysis. Effect sizes were expressed as odds ratio (OR) and mean differences (MD)/standardised MD (SMD) with 95% confidence intervals (CI) for categorical and continuous variables. RESULTS: Individuals presenting with early-onset CHD (age <65 years) compared to late-onset CHD had higher mean body mass index (MD 1.07 kg/m2; 95% CI 0.31-1.83), total cholesterol (SMD 0.43; 95% CI 0.23-0.62), low-density lipoprotein (SMD 0.26; 95% CI 0.15-0.36) and triglycerides (SMD 0.50; 95% CI 0.22-0.68) with lower high-density lipoprotein-cholesterol (SMD 0.26; 95% CI -0.42--0.11). They were more likely to be smokers (OR 1.76, 95% CI 1.39-2.22) and have a positive family history of CHD (OR 2.08, 95% CI 1.74-2.48). They had lower mean systolic blood pressure (MD 4.07 mmHg; 95% CI -7.36--0.78) and were less likely to have hypertension (OR 0.47, 95% CI 0.39-0.57), diabetes mellitus (OR 0.56, 95% CI 0.51-0.61) or stroke (OR 0.31, 95% CI 0.24-0.42). CONCLUSION: A focus on weight management and smoking cessation and aggressive management of dyslipidaemia in young adults may reduce the risk of early-onset CHD.

Do Chest Pain Characteristics in Patients with Acute Myocardial Infarction Differ between Those with and without Obstructive Coronary Artery Disease?

The universal definition of acute myocardial infarction (MI) requires both evidence of myocardial injury and myocardial ischaemia. In MINOCA (MI with non-obstructive coronary arteries), patients must fulfil this MI criteria, but is their chest pain similar to those who have MI with obstructive CAD (MICAD)? This study compares prospectively collected chest pain features between patients with MINOCA and MICAD. Utilising the Coronary Angiogram Database of South Australia (CADOSA), consecutive MI patients were categorized as MINOCA or MICAD based on angiographic findings. Chest pain data were collected via direct patient interviews by trained staff members. Of 6811 consecutive patients fulfilling a clinical MI diagnosis, 411 (6.0%) were MINOCA, and 5948 MICAD. The MINOCA patients were younger, more often female and had less cardiovascular risk factors than those with MICAD. There were no significant differences in chest pain characteristics between the MINOCA and MICAD cohorts in relation to pain location, quality, associated symptoms, or duration. In conclusion, MINOCA patients have chest pain characteristics that are indistinguishable from MICAD patients, suggesting that their pain is ischaemic in nature. Thus, in the presence of positive myocardial injury markers, ischaemic chest pain fulfils the universal criteria for MI, despite the absence of obstructive coronary artery disease.

Risk Factors for Premature Coronary Heart Disease in Women Compared to Men: Systematic Review and Meta-Analysis.

Background: We aimed to systematically examine literature on the prevalence of known modifiable and nonmodifiable risk factors for premature coronary heart disease (PCHD) in women compared with men. Materials and Methods: PubMed, CINAHL, Embase, and Web of Science databases were searched. Review protocol is registered in PROSPERO (CRD42020173216). Quality was assessed using the National Heart, Lung, and Blood Institute tool. Review Manager 5.3 was used for meta-analysis. Effect sizes were expressed as odds ratio (OR) and mean differences/standardized mean differences (SMD) with 95% confidence intervals (CIs) for categorical and continuous variables. Results: In this PCHD cohort (age <65 years), the mean age of presentation in women was 3 years older than men. Women had higher total cholesterol (SMD 0.11; 95% CI 0.00 to 0.23) and higher high-density lipoprotein cholesterol (SMD 0.49; 95% CI 0.29 to 0.69). Women were more likely to have hypertension (OR 1.51, 95% CI 1.42 to 1.60), diabetes mellitus (OR 1.78, 95% CI 1.55 to 2.04), obesity (OR 1.33, 95% CI 1.24 to 1.42), metabolic syndrome (OR 3.73, 95% CI 1.60 to 8.69), stroke (OR 1.63, 95% CI 1.51 to 1.77), peripheral vascular disorder (OR 1.67, 95% CI 1.43 to 1.96), and depression (OR 2.29, 95% CI 1.96 to 2.67). Women were less likely to be smokers (OR 0.60, 95% CI 0.55 to 0.66), have reported alcohol intake (OR 0.36, 95% CI 0.33 to 0.40), and reported use of illicit drug (OR 0.32, 95% CI 0.16 to 0.62). Conclusions: Risk factor profile in PCHD has a clear sex difference that supports early, aggressive, holistic, but sex-specific, approach to prevention.

Harmonising Individual Patient Level Cardiac Registry Data Across the Asia Pacific Region-A Feasibility Study of In-Hospital Outcomes of STEMI Patients From the Asia Pacific Evaluation of Cardiovascular Therapies (ASPECT) Network.

OBJECTIVE: The Asia-Pacific Evaluation of Cardiovascular Therapies (ASPECT) collaboration was established to inform on percutaneous coronary intervention (PCI) in the Asia-Pacific Region. Our aims were to (i) determine the operational requirements to assemble an international individual patient dataset and validate the processes of governance, data quality and data security, and subsequently (ii) describe the characteristics and outcomes for ST-elevation myocardial infarction (STEMI) patients undergoing PCI in the ASPECT registry. METHODS: Seven (7) ASPECT members were approached to provide a harmonised anonymised dataset from their local registry. Patient characteristics were summarised and associations between the characteristics and in-hospital outcomes for STEMI patients were analysed. RESULTS: Six (6) participating sites (86%) provided governance approvals for the collation of individual anonymised patient data from 2015 to 2017. Five (5) sites (83%) provided >90% of agreed data elements and 68% of the collated elements had <10% missingness. From the registry (n=12,620), 84% were male. The mean age was 59.2±12.3 years. The Malaysian cohort had a high prevalence of previous myocardial infarction (34%), almost twice that of any other sites (p<0.001). Adverse in-hospital outcomes were the lowest in Hong Kong whilst in-hospital mortality varied from 2.7% in Vietnam to 7.9% in Singapore. CONCLUSIONS: Governance approvals for the collation of individual patient anonymised data was achieved with a high level of data alignment. Secure data transfer process and repository were established. Patient characteristics and presentation varied significantly across the Asia-Pacific region with this likely to be a major predictor of variations in the clinical outcomes observed across the region.

The Association of Obstructive Sleep Apnea in Ischemia with No Obstructive Coronary Artery Disease - A Pilot Study.

Obstructive sleep apnea (OSA) is increasingly recognized to be a risk factor for cardiovascular disease. This pilot study assessed the association of OSA and invasive coronary microvascular function in patients with ischemia with no obstructive coronary artery disease (INOCA). Forty-two patients with angina, were prospectively screened at a single tertiary centre covering the northern metropolitan area of South Australia, from February 2018 to December 2020 (ACTRN12618000149268). Forty patients were invited into to this observational study after coronary angiography demonstrated INOCA and functional coronary vasomotor disorder (n = 40). Twenty one participants subsequently underwent a sleep study for OSA diagnosis while 9 participants had prior formal diagnosis of OSA (ACTRN12618000227291). Of the 30 participants with OSA data, 87% (n = 26) had a diagnosis of OSA. Accordingly, 11 with mild severity, 7 with moderate severity and 8 with severe OSA. No OSA was observed in 4 participants. Participants with OSA were older [61.4±8.7 vs 49.9±9.7, P = 0.002] with similar clinical characteristics for the pattern and severity of angina and other co-morbidities. 73.3% (n = 22) had abnormal functional disorders of the epicardial coronary arteries and/or coronary microcirculation. On multivariate analysis, OSA was the only statistically significant association with functional coronary microvascular disorders [OR 53.95, 1.41 -2065.01, P = 0.032]. This study provided an observation of a significant correlation between INOCA with abnormal coronary vasomotor function and OSA in an Australian cohort. This correlation supports a possible pathophysiological interplay between these two conditions that needs to be further evaluated. The benefit of treatment of OSA in this subset remains unknown.

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.

Implementation and prospective evaluation of the Country Heart Attack Prevention model of care to improve attendance and completion of cardiac rehabilitation for patients with cardiovascular diseases living in rural Australia: a study protocol.

INTRODUCTION: Despite extensive evidence of its benefits and recommendation by guidelines, cardiac rehabilitation (CR) remains highly underused with only 20%-50% of eligible patients participating. We aim to implement and evaluate the Country Heart Attack Prevention (CHAP) model of care to improve CR attendance and completion for rural and remote participants. METHODS AND ANALYSIS: CHAP will apply the model for large-scale knowledge translation to develop and implement a model of care to CR in rural Australia. Partnering with patients, clinicians and health service managers, we will codevelop new approaches and refine/expand existing ones to address known barriers to CR attendance. CHAP will codesign a web-based CR programme with patients expanding their choices to CR attendance. To increase referral rates, CHAP will promote endorsement of CR among clinicians and develop an electronic system that automatises referrals of in-hospital eligible patients to CR. A business model that includes reimbursement of CR delivered in primary care by Medicare will enable sustainable access to CR. To promote CR quality improvement, professional development interventions and an accreditation programme of CR services and programmes will be developed. To evaluate 12-month CR attendance/completion (primary outcome), clinical and cost-effectiveness (secondary outcomes) between patients exposed (n=1223) and not exposed (n=3669) to CHAP, we will apply a multidesign approach that encompasses a prospective cohort study, a pre-post study and a comprehensive economic evaluation. ETHICS AND DISSEMINATION: This study was approved by the Southern Adelaide Clinical Human Research Ethics Committee (HREC/20/SAC/78) and by the Department for Health and Wellbeing Human Research Ethics Committee (2021/HRE00270), which approved a waiver of informed consent. Findings and dissemination to patients and clinicians will be through a public website, online educational sessions and scientific publications. Deidentified data will be available from the corresponding author on reasonable request. TRIAL REGISTRATION NUMBER: ACTRN12621000222842.

Impact of COVID-19 restrictions on pathology service utilisation.

BACKGROUND: Isolation and social distancing restrictions due to COVID-19 have the potential to impact access to healthcare services. AIMS: To assess the use of pathology services during the COVID-19 pandemic initial restrictions. METHODS: Repeated cross-sectional study of pathology tests utilisation during a baseline time period early in 2020 compared with pre-lockdown and lockdown due to COVID-19 in South Australia. The outcome measure was changed in a number of pathology tests compared to baseline period, particularly change in the number of troponin tests to determine potential impacts of lockdown on urgent care presentations. RESULTS: In the community setting, the ratio of a number of pathology tests pre-lockdown and post-lockdown versus baseline period decreased from 1.02 to 0.53 respectively. The exception was microbiology molecular tests, where the number of tests was more than three times higher in the lockdown period. The number of troponin tests in emergency departments decreased in the lockdown period compared to the baseline time period; however, there was no evidence of an association between tests result (positive vs negative) and time period (odds ratio (OR) 1.09; 95% confidence interval (CI) 0.97-1.22). There was an inverse relationship between age and time period (OR 0.995; 95% CI 0.993-0.997), indicating that fewer troponin tests were conducted in older people during the lockdown compared with the baseline period. CONCLUSION: COVID-19 restrictions had a significant impact on the use of pathology testing in both urgent and non-urgent care settings. Further studies are needed to investigate the effect on health outcomes as a result of the COVID-19 restrictions.