Healthcare exposures and associated risk of endocarditis after open-heart cardiac valve surgery.

BACKGROUND: Infective endocarditis (IE) following cardiac valve surgery is associated with high morbidity and mortality. Data on the impact of iatrogenic healthcare exposures on this risk are sparse. This study aimed to investigate risk factors including healthcare exposures for post open-heart cardiac valve surgery endocarditis (PVE). METHODS: In this population-linkage cohort study, 23,720 patients who had their first cardiac valve surgery between 2001 and 2017 were identified from an Australian state-wide hospital-admission database and followed-up to 31 December 2018. Risk factors for PVE were identified from multivariable Cox regression analysis and verified using a case-crossover design sensitivity analysis. RESULTS: In 23,720 study participants (median age 73, 63% male), the cumulative incidence of PVE 15 years after cardiac valve surgery was 7.8% (95% CI 7.3-8.3%). Thirty-seven percent of PVE was healthcare-associated, which included red cell transfusions (16% of healthcare exposures) and coronary angiograms (7%). The risk of PVE was elevated for 90 days after red cell transfusion (HR = 3.4, 95% CI 2.1-5.4), coronary angiogram (HR = 4.0, 95% CI 2.3-7.0), and healthcare exposures in general (HR = 4.0, 95% CI 3.3-4.8) (all p < 0.001). Sensitivity analysis confirmed red cell transfusion (odds ratio [OR] = 3.9, 95% CI 1.8-8.1) and coronary angiogram (OR = 2.6, 95% CI 1.5-4.6) (both p < 0.001) were associated with PVE. Six-month mortality after PVE was 24% and was higher for healthcare-associated PVE than for non-healthcare-associated PVE (HR = 1.3, 95% CI 1.1-1.5, p = 0.002). CONCLUSIONS: The risk of PVE is significantly higher for 90 days after healthcare exposures and associated with high mortality.

Data-driven collaborative QUality improvement in Cardiac Rehabilitation (QUICR) to increase program completion: protocol for a cluster randomized controlled trial.

BACKGROUND: Coronary heart disease (CHD) is the leading cause of deaths and disability worldwide. Cardiac rehabilitation (CR) effectively reduces the risk of future cardiac events and is strongly recommended in international clinical guidelines. However, CR program quality is highly variable with divergent data systems, which, when combined, potentially contribute to persistently low completion rates. The QUality Improvement in Cardiac Rehabilitation (QUICR) trial aims to determine whether a data-driven collaborative quality improvement intervention delivered at the program level over 12 months: (1) increases CR program completion in eligible patients with CHD (primary outcome), (2) reduces hospital admissions, emergency department presentations and deaths, and costs, (3) improves the proportion of patients receiving guideline-indicated CR according to national and international benchmarks, and (4) is feasible and sustainable for CR staff to implement routinely. METHODS: QUICR is a multi-centre, type-2, hybrid effectiveness-implementation cluster-randomized controlled trial (cRCT) with 12-month follow-up. Eligible CR programs (n = 40) and the individual patient data within them (n ~ 2,000) recruited from two Australian states (New South Wales and Victoria) are randomized 1:1 to the intervention (collaborative quality improvement intervention that uses data to identify and manage gaps in care) or control (usual care with data collection only). This sample size is required to achieve 80% power to detect a difference in completion rate of 22%. Outcomes will be assessed using intention-to-treat principles. Mixed-effects linear and logistic regression models accounting for clusters within allocated groupings will be applied to analyse primary and secondary outcomes. DISCUSSION: Addressing poor participation in CR by patients with CHD has been a longstanding challenge that needs innovative strategies to change the status-quo. This trial will harness the collaborative power of CR programs working simultaneously on common problem areas and using local data to drive performance. The use of data linkage for collection of outcomes offers an efficient way to evaluate this intervention and support the improvement of health service delivery. ETHICS: Primary ethical approval was obtained from the Northern Sydney Local Health District Human Research Ethics Committee (2023/ETH01093), along with site-specific governance approvals. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12623001239651 (30/11/2023) ( https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=386540&isReview=true ).

Predicting Adverse Outcomes Following Catheter Ablation Treatment for Atrial Flutter/Fibrillation.

BACKGROUND & AIM: To develop prognostic survival models for predicting adverse outcomes after catheter ablation treatment for non-valvular atrial fibrillation (AF) and/or atrial flutter (AFL). METHODS: We used a linked dataset including hospital administrative data, prescription medicine claims, emergency department presentations, and death registrations of patients in New South Wales, Australia. The cohort included patients who received catheter ablation for AF and/or AFL. Traditional and deep survival models were trained to predict major bleeding events and a composite of heart failure, stroke, cardiac arrest, and death. RESULTS: Out of a total of 3,285 patients in the cohort, 177 (5.3%) experienced the composite outcome-heart failure, stroke, cardiac arrest, death-and 167 (5.1%) experienced major bleeding events after catheter ablation treatment. Models predicting the composite outcome had high-risk discrimination accuracy, with the best model having a concordance index >0.79 at the evaluated time horizons. Models for predicting major bleeding events had poor risk discrimination performance, with all models having a concordance index <0.66. The most impactful features for the models predicting higher risk were comorbidities indicative of poor health, older age, and therapies commonly used in sicker patients to treat heart failure and AF and AFL. DISCUSSION: Diagnosis and medication history did not contain sufficient information for precise risk prediction of experiencing major bleeding events. Predicting the composite outcome yielded promising results, but future research is needed to validate the usefulness of these models in clinical practice. CONCLUSIONS: Machine learning models for predicting the composite outcome have the potential to enable clinicians to identify and manage high-risk patients following catheter ablation for AF and AFL proactively.

Sex- and Age-Specific Differences in Risk Profiles and Early Outcomes in Adults With Acute Coronary Syndromes.

BACKGROUND: Adults <55 years of age comprise a quarter of all acute coronary syndromes (ACS) hospitalisations. There is a paucity of data characterising this group, particularly sex differences. This study aimed to compare the clinical and risk profile of patients with ACS aged <55 years with older counterparts, and measure short-term outcomes by age and sex. METHOD: The study population comprised patients with ACS enrolled in the AUS-Global Registry of Acute Coronary Events (GRACE), Cooperative National Registry of Acute Coronary Syndrome Care (CONCORDANCE) and SNAPSHOT ACS registries. We compared clinical features and combinations of major modifiable risk factors (hypertension, smoking, dyslipidaemia, and diabetes) by sex and age group (20-54, 55-74, 75-94 years). All-cause mortality and major adverse events were identified in-hospital and at 6-months. RESULTS: There were 16,658 patients included (22.3% aged 20-54 years). Among them, 20-54 year olds had the highest proportion of ST-elevation myocardial infarction compared with sex-matched older age groups. Half of 20-54 year olds were current smokers, compared with a quarter of 55-74 year olds, and had the highest prevalence of no major modifiable risk factors (14.2% women, 12.7% men) and of single risk factors (27.6% women, 29.0% men), driven by smoking. Conversely, this age group had the highest proportion of all four modifiable risk factors (6.6% women, 4.7% men). Mortality at 6 months in 20-54 year olds was similar between men (2.3%) and women (1.7%), although lower than in older age groups. CONCLUSIONS: Younger adults with ACS are more likely to have either no risk factor, a single risk factor, or all four modifiable risk factors, than older patients. Targeted risk factor prevention and management is warranted in this age group.

Trends in Isolated Mitral Valve Repair or Replacement Surgery in Australia: A Statewide Cohort Linkage Study.

BACKGROUND: Global trends in mitral valve surgery (MVSx) suggest increasing repair compared with replacement, especially in the United States and European countries. The relative use, and outcomes of, MV repair and replacement in Australia are unknown. METHODS: New South Wales residents who underwent isolated MVSx between 2001 and 2017 were identified from the Admitted-Patient-Data-Collection database. Mortality outcomes were tracked to 31 Dec 2018 and adjusted based on age, sex, urgency of operation, and comorbidity status. RESULTS: The study cohort comprised 5,693 patients: 2020 (35%) underwent repair (MVr), 1,656 (29%) underwent mechanical replacement (mech.MVR), and 2017 (35%) underwent bioprosthetic replacement (bio.MVR). Respective median ages [interquartile range] were 67 yo [59-75 yo], 64 yo [55-71 yo], and 75 yo [68-80 yo] (p<0.001 across groups). Between 2001 and 2017, total MVSx increased steadily with population growth. Whereas the relative use of MVr remained static (34% to 38%), that for bio.MVR (22% to 50%) and mech.MVR (45% to 13%) changed significantly. MVr had the best outcome with 1.2% in-hospital, 2.5% 1-year, and 21.6% total cumulative mortality during a median follow-up of 6.5 years. Compared to MVr, the adjusted hazard ratio (aHR) for mech.MVR and bio.MVR for long-term mortality were 1.41 (95% confidence interval [CI]=1.24-1.61) and 1.73 (95% CI=1.53-1.95), respectively. Heart failure and sepsis were the main cardiovascular and noncardiovascular causes of death in all groups. CONCLUSION: In this statewide Australian cohort examined over 17 years, MVr is potentially underutilised despite having superior outcomes to MVR. Access to quality dataset which provides the indication for MVSx and quantitative clinical factors is critical to further improve MVr coverage and outcome MVSx.

Morbidity and mortality outcomes of patients requiring isolated tricuspid valve surgery: a retrospective cohort study of 537 patients in New South Wales between 2002 and 2018.

OBJECTIVES: The aim of the study was to evaluate mortality and morbidity outcomes following open-heart isolated tricuspid valve surgery (TVSx) with medium to long-term follow-up. DESIGN: Retrospective cohort study. SETTING: New South Wales public and private hospital admissions between 1 January 2002 and 30 June 2018. PARTICIPANTS: A total of 537 patients underwent open isolated TVSx during the study period. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome was all-cause mortality tracked from the death registry to 31 December 2018. Secondary morbidity outcomes, including admission for congestive cardiac failure (CCF), new atrial fibrillation (AF), infective endocarditis (IE), pulmonary embolism (PE) and insertion of a permanent pacemaker (PPM) or implantable cardioverter-defibrillator (ICD), were tracked from the Admitted Patient Data Collection database. Independent mortality associations were determined using the Cox regression method. RESULTS: A total of 537 patients underwent open isolated TVSx (46% male): median age (IQR) was 63.5 years (43.9-73.8 years) with median length of stay of 16 days (10-31 days). Main cardiovascular comorbidities were AF (54%) and CCF (42%); 67% had rheumatic tricuspid valve. In-hospital and total mortality were 7.4% and 39.3%, respectively (mean follow-up: 4.8 years). Cause-specific deaths were evenly split between cardiovascular and non-cardiovascular causes. Predictors of mortality included a history of CCF (HR=1.78, 95% CI 1.33 to 2.38, p<0.001) and chronic pulmonary disease (HR=2.66, 95% CI 1.63 to 4.33, p<0.001). In-hospital PPM rate was 10.0%. At 180 days, 53 (9.9%) patients were admitted for CCF, 25 (10.1%) had new AF, 7 (1.5%) had new IE and <1% had PE, post-discharge PPM or ICD insertion. CONCLUSION: Open isolated TVSx carries significant mortality risk, with decompensated CCF and new AF the most common morbidities encountered after surgery. This report forms a benchmark to compare outcomes with newer percutaneous tricuspid interventions.

Mortality outcomes in 35,433 patients admitted for acute haemorrhagic stroke in Australia: A population-linkage study.

Background: Haemorrhagic stroke (HS) is an important cardiovascular cause of mortality worldwide. Trends in admission rates and outcomes, and predictors of outcomes, post-HS in Australia remain unclear. Methods: All New South Wales residents, Australia, hospitalized with HS from 2002 to 2017 were identified from the Admitted-Patient-Data-Collection database. Admission rates were adjusted to population size by sex, age-groups and calendar-year. Mortality was tracked from the death registry to 31-Dec-2018 and adjusted for admission calendar-year, age, gender, referral source, surgical evacuation following HS and comorbidities. Results: The cohort comprised 35,433 patients (51.1% males). Overall age-adjusted mean(±SD) admission rates were higher for males (63.6 ± 6.2 vs 49.9 ± 4.4 admissions-per-100,000-persons-per-annum). Annual admission rates declined for both sexes from 2002 to 2017 especially in those ≥60yo. In-hospital and 1-year mortality rates were higher for females than males (25.0% vs 20.0% and 40.6% vs 35.9% respectively, all p < 0.001). Adjusted in-hospital and 1-year mortality declined for men and women, overall decreasing by 45% (odds ratio 0.55, 95% confidence interval [CI] = 0.47-0.64), and 31% (hazard ratio 0.69,95%CI = 0.63-0.76) respectively between 2002 and 2017. Independent predictors of increased in-hospital and 1-year mortality included increasing age and Charlson comorbidity index, while male sex, a history of hyperlipidaemia and current smoking, and surgical evacuation following HS were associated with reduced mortality (all p < 0.001). Conclusion: HS incidence increases markedly with age. Although age-adjusted HS admission rates and post HS mortality have fallen, HS remains associated with high early and 1-year mortality, with females consistently associated with worse outcomes. Strategies to improve outcomes of these patients remain a clinical priority.

Impact of coordinated care on adherence to antihypertensive medicines among adults experiencing polypharmacy in Australia.

BACKGROUND: Adherence to antihypertensives is key for blood pressure control. Most people with hypertension have several comorbidities and require multiple medicines, leading to complex care pathways. Strategies for coordinating medicine use can improve adherence, but cumulative benefits of multiple strategies are unknown. METHODS: Using dispensing claims for a 10% sample of eligible Australians, we identified adult users of antihypertensives during July 2018-June 2019 who experienced polypharmacy (≥5 unique medicines). We measured medicine use reflecting coordinated medicine management in 3 months before and including first observed dispensing, including: use of simple regimens for each cardiovascular medicine; prescriber continuity; and coordination of dispensings at the pharmacy. We measured adherence (proportion of days covered) to antihypertensive medicines in the following 12 months, and used logistic regression to assess independent associations and interactions of adherence with these measures of care. RESULTS: We identified 202 708 people, of which two-thirds (66.6%) had simple cardiovascular medicine regimens (one tablet per day for each medicine), two-thirds (63.3%) were prescribed >75% of medicines from the same prescriber, and two-thirds (65.5%) filled >50% of their medicine on the same day. One-third (28.4%) of people experienced all three measures of coordinated care. Although all measures were significantly associated with higher adherence, adherence was greatest among people experiencing all three measures (odds ratio = 1.63; 95% confidence interval: 1.55-1.72). This interaction was driven primarily by effects of prescriber continuity and dispensing coordination. CONCLUSIONS: Coordinating both prescribing and dispensing of medicines can improve adherence to antihypertensives, which supports strategies consolidating both prescribing and supply of patients' medicines.

Post-discharge pharmacotherapy in people with atrial fibrillation hospitalised for acute myocardial infarction: an Australian cohort study 2018-2022.

BACKGROUND: Dual antiplatelet therapy with P2Y12 inhibitors (P2Y12i) and aspirin following acute myocardial infarction (AMI) prevents future ischaemic events. People with atrial fibrillation (AF) also require oral anticoagulants (OAC), increasing bleeding risk. Guidelines recommend post-discharge prescribing of direct OAC with clopidogrel and discontinuation of P2Y12i after 12 months, but little is known about use in clinical practice. AIM: To describe post-discharge use of OACs and P2Y12i in people with AF and a history of OAC use hospitalised for AMI. METHODS AND RESULTS: We identified 1,330 people hospitalised for AMI with a diagnosis of AF and history of OAC use in New South Wales, Australia, July 2018-June 2020. We identified three aspects of post-discharge antithrombotic medicine use with possible safety implications: (1) not being dispensed OACs; (2) dispensing OAC and P2Y12i combinations associated with increased bleeding (involving warfarin, ticagrelor or prasugrel); and (3) P2Y12i use longer than 12 months.After discharge, 74.3% of people were dispensed an OAC, 45.4% were dispensed a P2Y12i, and 35.8% were dispensed both. People with comorbid heart failure or cancer were less likely to receive OACs. Only 11.2% of people dispensed both an OAC and P2Y12i received combinations associated with increased bleeding; this was more common among people with chronic kidney disease or prior warfarin or statin use. 44.6% of people dispensed both medicines continued P2Y12i for over 12 months; this was more common in people who received a revascularisation or lived in areas of social disadvantage. CONCLUSION: We identified potential gaps in pharmacotherapy, including underuse of recommended therapies at discharge, use of combinations associated with increased bleeding, and P2Y12i use beyond 12 months. Prescribing vigilance across both hospital and community care is required.

Comparing the long-term outcomes in chronic coronary syndrome patients with prior ST-segment and non-ST-segment elevation myocardial infarction: findings from the TIGRIS registry.

OBJECTIVES: Compared with ST-segment elevation myocardial infarction (STEMI) patients, non-STEMI (NSTEMI) patients have more comorbidities and extensive coronary artery disease. Contemporary comparative data on the long-term prognosis of stable post-myocardial infarction subtypes are needed. DESIGN: Long-Term rIsk, clinical manaGement and healthcare Resource utilisation of stable coronary artery dISease (TIGRIS) was a multinational, observational and longitudinal cohort study. SETTING: Patients were enrolled from 350 centres, with >95% coming from cardiology practices across 24 countries, from 19 June 2013 to 31 March 2017. PARTICIPANTS: This study enrolled 8277 stable patients 1-3 years after myocardial infarction with ≥1 additional risk factor. OUTCOME MEASURES: Over a 2 year follow-up, cardiovascular events and deaths and self-reported health using the EuroQol 5-dimension questionnaire score were recorded. Relative risk of clinical events and health resource utilisation in STEMI and NSTEMI patients were compared using multivariable Poisson regression models, adjusting for prognostically relevant patient factors. RESULTS: Of 7752 patients with known myocardial infarction type, 46% had NSTEMI; NSTEMI patients were older with more comorbidities than STEMI patients. NSTEMI patients had significantly poorer self-reported health and lower prevalence of dual antiplatelet therapy at hospital discharge and at enrolment 1-3 years later. NSTEMI patients had a higher incidence of combined myocardial infarction, stroke and cardiovascular death (5.6% vs 3.9%, p<0.001) and higher all-cause mortality (4.2% vs 2.6%, p<0.001) compared with STEMI patients. Risks were attenuated after adjusting for other patient characteristics. Health resource utilisation was higher in NSTEMI patients, although STEMI patients had more cardiologist visits. CONCLUSIONS: Post-NSTEMI chronic coronary syndrome patients had a less favourable risk factor profile, poorer self-reported health and more adverse cardiovascular events during long-term follow-up than individuals post STEMI. Efforts are needed to recognise the risks of stable patients after NSTEMI and optimise secondary prevention and care. TRIAL REGISTRATION NUMBER: NCT01866904.