Understanding the contribution of general medical services to acute inpatient care in Victorian public hospitals.

BACKGROUND: General medicine is an integral part of health services, yet there is little data highlighting their contribution to acute hospital care in Australia. AIMS: To utilise the Victorian Department of Health's administrative dataset for hospital admissions to evaluate the relative contribution and trends over time of general medical services to acute multiday inpatient hospital separations in the Victorian public healthcare system. METHODS: A retrospective time-series study of general medical activity compared to other major specialties using hospital-level data provided by the Department of Health: (i) extrapolation from diagnosis-related group (DRG) activity data (2011-2021) and, (ii) directly reported discharge unit-based activity (available from 2018). Acute multiday separations of all patients aged ≥18 years from all metropolitan and rural Victorian public hospitals were included. RESULTS: Using the DRG-based data, general medicine ranked as the largest care provider of all specialties studied, accounting for 12.1% of separations. Despite the largest increase at a rate of 2831 separations/year (0.336%/year of total, P < 0.001) compared to others, mean length of stay declined by 0.08 days/year (P < 0.001). These findings were significant for metropolitan and rural hospitals. The use of directly reported discharge unit-based data also ranked general medicine as the largest care provider accounting for 32.9% of total separations, with rural hospital general medical services contributing nearly 50% of all multiday separations. CONCLUSIONS: Both DRG-based data and discharge unit-based data indicate that general medicine is the largest provider of acute multiday inpatient care in Victorian hospitals. The estimate of contribution of general medicine differed between the two datasets as DRG data likely over-represents the role of other specialties possibly due to assumptions regarding specialty management of varying groups of diagnoses.

Cognitive Dysfunction in Heart Failure: Pathophysiology and Implications for Patient Management.

PURPOSE OF REVIEW: There is increasing recognition of the prevalence and impact of cognitive dysfunction (CD) in heart failure (HF) patients. This contemporary review appraises the evidence for epidemiological association, direct pathophysiological links and emerging pharmacological and non-pharmacological interventions. Furthermore, we present evidence for care models that aim to mitigate the morbidity and poor quality of life associated with these dual processes and propose future work to improve outcomes. RECENT FINDINGS: CD disproportionately affects heart failure patients, even accounting for known comorbid risk factors, and this may extend to subclinical left ventricular dysfunction. Neuroimaging studies now provide evidence of anatomical and functional differences which support previously postulated mechanisms of reduced cerebral blood flow, micro-embolism and systemic inflammation. Interventions such as multidisciplinary ambulatory HF care, education and memory training improve HF outcomes perhaps to a greater degree in those with comorbid CD. Additionally, optimisation of standard heart failure care (cardiac rehabilitation, pharmacological and device therapy) may lead to additional cognitive benefits. Epidemiological, neuroimaging and intervention studies provide evidence for the causal association between HF and CD, although evidence for Alzheimer's dementia is less certain. Specific reporting of cognitive outcomes in HF trials and evaluation of targeted interventions is required to further guide care provision.

Research activities in general medicine: a scoping survey by the Internal Medicine Society of Australia and New Zealand.

BACKGROUND: In developing an effective framework for a collaborative research network (RN) that supports members involved in research, the Internal Medicine Society of Australia and New Zealand (IMSANZ) required a better understanding of the current level of research activity and engagement by general physicians, and factors influencing such engagement. AIMS: To explore the current research landscape amongst general physicians in Australia and Aotearoa New Zealand. METHODS: A questionnaire exploring research participation, scope, research enablers and barriers was disseminated to IMSANZ members over a 3-month period. Core functions of IMSANZ-RN, research priorities, potential solutions to perceived barriers and required level of support were also evaluated. RESULTS: A total of 82 members, mostly senior medical staff (74.4%), responded to the survey (11.8% response rate). More than 70% were involved in impactful research across multiple disciplines, encompassing a wide range of research themes and topics. However, there is limited support and resources available to conduct research, with most projects being self-instigated and self-funded. There is overwhelming support to increasing the profile of research in general medicine through the establishment of IMSANZ-RN, whose principal purposes, as identified by respondents, are to foster collaboration, promote research, provide research education and training, and share information among general physicians. Quality improvement studies (56.1%) and clinical trials (41.5%) were also identified as priority research types. CONCLUSIONS: This study has profiled the constraints faced by general physicians in conducting high-quality collaborative research and provides insights into what is needed to support greater research engagement, through development of a discipline-specific clinical RN.

Associations of subclinical heart failure and atrial fibrillation with mild cognitive impairment: a cross-sectional study in a subclinical heart failure screening programme.

OBJECTIVES: Effective identification and management of subclinical left ventricular (LV) dysfunction (LVD) and subclinical atrial fibrillation (AF) by screening elderly populations might be compromised by mild cognitive impairment (MCI). We sought to characterise the prevalence and profile of MCI and evaluate associations with LV and left atrial (LA) dysfunction and AF, in a trial of screening for subclinical LVD and AF. DESIGN: Cross-sectional. SETTING: Australian, community-based intervention trial. PARTICIPANTS: Adults aged ≥65 years with ≥1 LVD risk factors without ischaemic heart disease (n=337). OUTCOME MEASURES: The Montreal cognitive assessment (MoCA) was obtained. Subclinical LVD was defined as echocardiographic global longitudinal strain ≤16%, diastolic dysfunction or LV hypertrophy; abnormal LA reservoir strain (LARS) was defined as <24%. Subclinical AF was detected using a single-lead portable electrocardiographic device in those without pre-existing AF who gave consent (n=293). RESULTS: Subclinical LVD was found in 155 (46%), abnormal LARS in 9 (3.6%) and subclinical AF in 11 (3.8%). MoCA score consistent with MCI (<26) was found in 101 (30%); executive function (69%) and delayed recall (93%), were the most frequently abnormal domains. Compared with normal cognition, MCI was associated with non-adherence to AF screening (25% vs 40%, p=0.01). In multivariable logistic regression modelling, educational achievement, systolic blood pressure, body mass index and waist-to-hip ratio were independently associated with MCI. However, neither subclinical AF nor any measure of cardiac dysfunction, were associated with MCI. CONCLUSIONS: The 30% prevalence of MCI among elderly subjects with risk factors for subclinical LVD and AF has important implications for screening strategies and management. However, MCI is not associated with subclinical myocardial dysfunction nor subclinical AF. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry (ACTRN12617000116325).

Machine Learning of ECG Waveforms to Improve Selection for Testing for Asymptomatic Left Ventricular Dysfunction.

OBJECTIVES: The purpose of this study was to identify whether machine learning from processing of continuous wave transforms (CWTs) to provide an "energy waveform" electrocardiogram (ewECG) could be integrated with echocardiographic assessment of subclinical systolic and diastolic left ventricular dysfunction (LVD). BACKGROUND: Asymptomatic LVD has management implications, but routine echocardiography is not undertaken in subjects at risk of heart failure. Signal processing of the surface ECG with the use of CWT can identify abnormal myocardial relaxation. METHODS: EwECG and echocardiography were undertaken in 398 participants at risk of heart failure (HF). Reduced global longitudinal strain (GLS ≤16%)), diastolic abnormalities (E/e' >15, left atrial enlargement with E/e' >10 or impaired relaxation) or LV hypertrophy defined LVD. EwECG feature selection and supervised machine-learning by random forest (RF) classifier was undertaken with 643 CWT-derived features and the ARIC (Atherosclerosis Risk In Communities) heart failure risk score. RESULTS: The ARIC score and 18 CWT features were selected to build a RF predictive model for LVD in a training dataset (n = 287; 60% female, median age 71 [interquartile range: 68 to 74] years). Model performance was tested in an independent group (n = 111; 49% female, median age 61 years [59 to 66 years]), demonstrating 85% sensitivity and 72% specificity (area under the receiver-operating characteristic curve [AUC]: 0.83; 95% confidence interval [CI]: 0.74 to 0.92). With ARIC score removed, sensitivity was 88% and specificity, 70% (AUC: 0.78; 95% CI: 0.70 to 0.86). RF models for reduced GLS and diastolic abnormalities including similar features had sensitivities that were unsuitable for screening. Conventional candidates for LVD screening (ARIC score, N-terminal pro-B-type natriuretic peptide, and standard automated ECG analysis) had inferior discriminative ability. Integration of ewECG in screening of people at risk of HF would reduce need for echocardiography by 45% while missing 12% of LVD cases. CONCLUSIONS: Machine learning applied to ewECG is a sensitive screening test for LVD, and its integration into screening of patients at risk for HF would reduce the number of echocardiograms by almost one-half.

Feasibility, Reproducibility, and Clinical Implications of the Novel Fully Automated Assessment for Global Longitudinal Strain.

BACKGROUND: Despite evidence of its usefulness, measurement of global longitudinal strain (GLS) has not been widely accepted as a clinical routine, because it requires proficiency and is time consuming. Automated assessment of GLS may be the solution for this situation. The aim of this study was to investigate the feasibility, reproducibility, and predictive value of automated strain analysis compared with semiautomated and manual assessment of GLS. METHODS: In this validation study, different methods for the assessment of GLS were applied to echocardiograms from 561 asymptomatic subjects (mean age, 71 ± 5 years) with heart failure risk factors, recruited from the community. All patients had both data on follow-up outcomes (new heart failure and cardiac death) and interpretable echocardiographic images for strain analysis. Measurement of GLS was repeated using the same apical images with three different measurement packages as follows: (1) fully automated GLS (AutoStrain), (2) semiautomated GLS (automated, corrected by a trained investigator), and (3) manual GLS (standard manual assessment by a trained investigator). RESULTS: AutoStrain measurements were technically feasible in 99.5% of patients. Calculation times for automated (0.5 ± 0.1 min/patient) and semiautomated assessment (2.7 ± 0.6 min/patient) were significantly shorter than for manual assessment (4.5 ± 1.6 min/patient; P < .001 for both). Approximately 40% of patients were thought to need manual correction after automatic calculation of GLS. Therefore, there was considerable discordance between automated and semiautomated and manual GLS. Over a median of 12 months of follow-up, cardiovascular events (new heart failure and cardiac death) occurred in 66 patients (11.8%). Automated GLS showed the potential to correctly detect normal and abnormal systolic function and predict cardiac events; the predictive value was inferior to that of semiautomated GLS. CONCLUSIONS: A novel fully automated assessment for GLS may provide a technically feasible, rapidly reproducible, and clinically applicable means of assessing left ventricular function, but a substantial number of automatic traces still need manual correction by experts. At the present stage, the semiautomated approach using this novel automated software seems to provide a better balance between feasibility and clinical relevance.

Impact of disease stage on the performance of strain markers in the prediction of atrial fibrillation.

BACKGROUND: Assessing atrial fibrillation (AF) risk may be useful in primary prevention (PP; people with risk factors) and secondary prevention (SP; eg. embolic stroke of unknown source). We sought whether disease stage influenced the prediction of AF by echocardiography. METHODS: We compared a PP cohort (351 community-based participants ≥65 years with ≥1 risk factor for AF) and a SP cohort (453 patients after transient ischemic attack or stroke). LV global longitudinal strain (GLS) and left atrial reservoir strain (LARS) were measured from DICOM images. AF was diagnosed by 12 lead ECG, Holter or by single lead monitor over median follow-up of 22 months (PP) and 35 months (SP). The clinical and echocardiographic characteristics of those with AF were compared to those in sinus rhythm. Nested Cox-regression models assessed for independent and incremental predictive value of LARS and GLS in both cohorts. RESULTS: AF developed in 42 PP (12%) and 60 SP (13%), and was associated with age, higher CHARGE-AF score, increased LA volume and LV mass (p < 0.05). Patients developing AF had reduced GLS (17 ± 3.5% vs. 20 ± 3%, p < 0.001) and LARS (28 ± 11% vs. 35 ± 8%, p < 0.001). However, the predictive value of both GLS (area under the ROC curve 0.83 vs 0.56, p < 0.001) and LARS (0.83 vs 0.57, p < 0.001) was greater in SP than PP. LARS was independently associated with AF in both cohorts (p < 0.05), but GLS was only independently associated in the SP cohort. CONCLUSION: AF risk assessment with LARS is suitable for different risk cohorts, but GLS is more useful in SP.

Association of Asymptomatic Diastolic Dysfunction Assessed by Left Atrial Strain With Incident Heart Failure.

OBJECTIVES: This study is to establish the association of left atrial reservoir strain (LARS) with incident heart failure (HF), and the impact of substituting LARS for left atrial (LA) volume index (LAVI) in diastolic assessment. BACKGROUND: LARS measures passive LA stretch and is a sensitive marker of left ventricular diastolic dysfunction (DD). The potential contribution of LARS to diastolic assessment is unclear. METHODS: Baseline clinical and echocardiographic assessments were obtained in 758 asymptomatic, community-dwelling elderly subjects (age 70 [interquartile range: 67 to 74] years, 53% women) with nonischemic HF risk factors. LARS-defined DD (LARS-DD) was assessed by speckle-tracking echocardiography, and grades were assigned as normal (>35%), grade 1 (25% to 35%) and grade 2 (≤24%). DD grade using current recommendations was compared with grading using LARS <24% in place of LAVI >34 ml/m2. Patients were followed for up to 2 years for incident HF. RESULTS: LA strain analysis was feasible in 738 (97%) patients; average LARS was 39% (range 34% to 43%). Incident HF was associated with LARS-DD grade; 8 (36%) of those had grade 2+, 14 (10%) had grade 1, and 39 (9%) had normal function (p < 0.001). LARS-DD grade 2+ predicted incident HF after adjustment for clinical and echocardiographic markers (adjusted hazard ratio: 2.5; 95% confidence interval: 1.02 to 6.3; p = 0.049); there was no significant HF risk associated with LARS-DD grade 1. Dichotomized abnormal LARS <24% had an adjusted hazard ratio of 2.9 (95% confidence interval: 1.25 to 6.79; p = 0.013). Substituting LARS for LAVI provided a 75% reduction in indeterminate diastolic function; all were recategorized as normal. There was no increased risk associated normal diastolic function by this grading compared to conventional grading (C-statistic = 0.76 for both models). CONCLUSIONS: LARS-DD grade 2+ is associated with incident HF in the elderly, independent of LAVI. The substitution of LARS for LAVI reduces the number of indeterminate cases without impacting prognosis in normal diastolic function and grade 1 DD.

Echocardiographic Risk Assessment to Guide Screening for Atrial Fibrillation.

BACKGROUND: Although atrial fibrillation (AF) is a significant population health burden, and an avoidable cause of stroke, AF screening remains controversial. The aim of this study was to investigate whether coincidental echocardiography could provide information about patients at risk for AF. METHODS: Asymptomatic participants ≥65 years of age with more than one AF risk factor (N = 445) undergoing echocardiography for risk evaluation were followed over a median of 15 months for incident AF. Left atrial volume index (LAVi), left ventricular (LV) global longitudinal strain (GLS; absolute value), left atrial (LA) strain, and LV mass were measured. During the follow-up period, AF was diagnosed clinically by primary care physicians or by using a single-lead portable electrocardiographic monitoring device (five 60-sec recordings performed by participants over 1 week). RESULTS: AF was diagnosed in 45 patients (10%; mean age, 70.5 ± 4.2 years; 55% women). AF detection was higher in those with LV hypertrophy, GLS < 16%, LAVi > 34 mL/m2, and LA reservoir strain < 34%. GLS, LAVi, and LA reservoir strain were independently associated with AF (P < .05). Those with AF had reduced GLS, higher LAVi, and higher LV mass (P < .05), but LA strain was similar in both groups (P > .05). GLS and LAVi were the strongest predictors, and cut points of 14.3% for GLS and 39 mL/m2 were associated with increased risk for developing AF. Those with all four risk parameters (LV hypertrophy, GLS < 16%, LA reservoir strain < 34%, and LAVi > 34 mL/m2) had a 60% AF detection rate, compared with 7% without these features (P = .004). CONCLUSION: Echocardiography is widely used in patients at risk for AF, and simple LV and LA measurements may be used to enrich the process of AF screening.

Impact of socioeconomic status on incident heart failure and left ventricular dysfunction: systematic review and meta-analysis.

AIMS: Socioeconomic status (SES) is recognizably linked with incident heart failure (HF) risk and the association of SES with geography presents a potential target for geographical location of preventive health services. To better inform policy we sought to quantify the independent association between SES and incident HF and investigate differences by type of SES measure. METHODS AND RESULTS: MEDLINE and EMBASE were searched up to August 2018. Observational studies and randomized trials reporting adjusted HF incidence by stratified socioeconomic measures were included. Effect sizes reflected HF incidence in the lowest vs. highest SES stratum and were pooled using a random-effects model. Low SES referred to the lowest resource stratum, the definition of which varied across studies: meta-analysis was only performed where strata were comparable. Statistical heterogeneity was assessed using the I2 statistic. Eleven studies comprising 6 308 006 individuals and 104 217 HF events found that low SES was associated with an increase in risk of incident HF ranging between 43% and 87% depending on SES measure, with an overall estimate of 62% [hazard ratio (HR) 1.62, 95% confidence interval (CI) 1.50-1.76]. By individual measure, HRs of 1.66 (95% CI 1.3-2.11), 1.87 (95% CI 1.33-2.62), and 1.54 (95% CI 1.22-1.95) were observed for education, income, and occupation, respectively. For area-level indexes, HRs were 1.43 (95% CI 1.2-1.69) (Carstairs index) and 1.61 (95% CI 1.56-1.65) (index of multiple deprivation). CONCLUSION: Low SES assessed by all common measures confers independent risk for incident HF. These findings carry implications for the design and delivery of HF prevention programmes.

Association between socioeconomic status and incident atrial fibrillation.

BACKGROUND: Low socioeconomic status is associated with cardiovascular diseases, and an association with atrial fibrillation (AF) could guide screening. AIM: To investigate if indices of advantage/disadvantage (IAD), index of education/occupation (IEO) and index of economic resources were associated with incident AF, independent of risk factors and cardiac function. METHODS: We studied community-based participants aged ≥65 years with AF risk factors (n = 379, age 70 ± 4 years, 45% men). The CHARGE-AF score (a well validated AF risk score) was used to assess 5-year risk of developing AF. Participants also had baseline echocardiograms. IAD, IEO and index of economic resources were obtained from the 2011 Socio-Economic Indexes for Areas score, in which higher decile ranks indicate more advantaged areas. Patients were followed up for incident AF (median 21 (range 5-31) months), with AF diagnosed by clinical review, including 12-lead electrocardiogram (ECG), as well as single-lead portable ECG monitoring used to record 60 s ECG tracings five times/day for 1 week. Cox proportional hazards models were used to assess the association between socioeconomic status and incident AF. RESULTS: Subjects with AF (n = 50, 13%) were more likely to be male (64 vs 42%, P = 0.003) and had higher CHARGE-AF score (median 7.1% (5.2-12.8%) vs 5.3% (3.3-8.6%), P < 0.001). Areas with lower socioeconomic status (IAD and IEO) had a higher risk of incident AF independent of LV function and CHARGE-AF score (hazard ratio for IAD 1.16, 95% confidence interval 1.05-1.29, P = 0.005 and hazard ratio for IEO 1.18, 95% confidence interval 1.07-1.30, P = 0.001). CONCLUSION: Regional socioeconomic status is associated with risk of incident AF, independent of LV function and clinical risk. This association might permit better regional targeting of prevention.

Stenotic flow reserve derived from quantitative coronary angiography has modest but incremental value in predicting functionally significant coronary stenosis as evaluated by fractional flow reserve.

BACKGROUND: Stenotic flow reserve (SFR) derived from quantitative coronary angiography (QCA) has been correlated with myocardial ischaemia as determined by pharmacological stress echocardiography. However, the diagnostic accuracy of SFR in predicting functionally significant coronary stenosis as assessed by the gold standard, fractional flow reserve (FFR), has not been previously characterised. METHODS: Patients who underwent coronary angiography and FFR assessment between January 2010 and February 2012 in a single tertiary centre were retrospectively assessed. QCA parameters such as minimal lumen diameter (MLD), lesion length, diameter stenosis (DS), SFR, turbulent resistance (TR) and Poiseuille resistance (PR) were assessed. Significant FFR was defined as FFR ≤0.8. The diagnostic accuracy of QCA parameters to predict significant FFR was assessed by independent t-test and receiver operator characteristic (ROC) curve. Statistical significance was defined as P value of <0.05. RESULTS: The study included 272 patients (age: 64±11, 70% males) and 415 vessels. There were 180 (43%) vessels which were FFR significant. The mean FFR value for all vessels was 0.81±0.11. On comparison of AUC for predicting significant FFR, SFR (AUC =0.76) had the highest diagnostic accuracy compared to PR (AUC =0.75), % DS (AUC =0.73), TR (AUC =0.69), MLD (AUC =0.71) and DS >50% (AUC =0.64). Using a retrospectively determined optimal cut-off value of 3.51, the sensitivity of stenotic-flow-reserve was modest at 56% with good specificity of 81%. DS >50% had a sensitivity of 47% and specificity of 82% in predicting significant FFR. There was incremental predictive value when SFR was added to DS >50% on integrated discrimination improvement index (IDI =0.103, P<0.001) and net reclassification index (NRI =0.72, P<0.001). CONCLUSIONS: SFR has modest diagnostic accuracy for predicting significant FFR but adds incremental predictive value to DS >50% for predicting significant FFR.

ST-elevation myocardial infarction in a young adult secondary to giant coronary aneurysm thrombosis: an important sequela of Kawasaki disease and a management challenge.

Thrombosis of a coronary artery aneurysm (CAA) is a rare trigger for ST-elevation myocardial infarction (STEMI) and an important cause of STEMI in young adults previously affected by Kawasaki disease. Initial management should proceed in line with standard STEMI-management guidelines advocating antiplatelet medication and emergency coronary angiography. Acute CAA thrombosis presents the interventional cardiologist with unique challenges during attempted percutaneous revascularisation. In the absence of consensus guidelines, experiential reporting can therefore be of great value. We report on a 36-year-old Vietnamese woman presenting with an inferior STEMI secondary to two giant thrombosed aneurysms of the right coronary artery. Coronary wiring and thrombus aspiration temporarily improved coronary flow but recurrent thrombus with distal embolisation resulted in ventricular fibrillation and cardiogenic shock. Emergency surgical revascularisation subsequently provided a definitive and successful outcome. We discuss the challenges of percutaneous coronary intervention in this scenario and review previous reports to give an overview of principles of decision-making and management.

A novel coronary angiography index (DILEMMA score) for prediction of functionally significant coronary artery stenoses assessed by fractional flow reserve: A novel coronary angiography index.

BACKGROUND: Angiographic evaluation of diameter stenosis has modest predictive value for functionally significant coronary artery stenoses as assessed by fractional flow reserve (FFR). Lesion length and assessment of area of myocardium at risk (Bypass Angioplasty Revascularization Investigation [BARI] Myocardial Jeopardy Index [MJI]) subtended by the stenotic coronary arteries are also predictors of functionally significant coronary artery stenoses. We sort to assess the diagnostic accuracy of DILEMMA score, which combines minimal lumen diameter (MLD), lesion length, and BARI MJI in prediction of significantly reduced FFR (≤0.8). METHODS: We assessed patients who underwent coronary angiography and FFR. Lesion length and MLD were assessed by quantitative coronary angiography. Estimation of area of myocardium at risk subtended by coronary stenoses was performed using the BARI MJI. RESULTS: A total of 296 patients (age 64 ± 10.6 years, 68% male, 497 vessels) were included. DILEMMA score was significantly higher in vessels with significant FFR, 6.09 ± 3.23 versus 3.84 ± 2.99 (P < .001). In the derivation cohort, the optimism-adjusted Harrell c statistic for DILEMMA score was 0.82 compared with 0.76 for BARI MJI, 0.75 for lesion length, and 0.7 for MLD. In the validation cohort, the c-statistic for DILEMMA score, BARI MJI, lesion length, and MLD was 0.88, 0.77, 0.81, and 0.72, respectively. The DILEMMA score was a better predictor of FFR ≤0.8 compared with MLD, lesion length, and BARI MJI individually (P < .001, P < .02, and P < .045, respectively) on Bonferroni-adjusted pairwise comparison. CONCLUSIONS: DILEMMA score, taking into account MLD, lesion length, and BARI MJI, may have incremental predictive value beyond the individual indices alone for detecting functionally significant coronary artery stenoses.