Search

Key Points: Question: Does atrial fibrillation catheter ablation have an impact on mental health? Findings: In this randomized clinical trial of 100 patients with symptomatic atrial fibrillation, catheter ablation with reduction in arrhythmia burden and antiarrhythmic drug use was associated with improvement in markers of psychological distress compared with medical therapy alone. Meaning: Improvement of severe psychological distress may be an additional benefit of catheter ablation treatment for atrial fibrillation. Importance: The impact of atrial fibrillation (AF) catheter ablation on mental health outcomes is not well understood. Objective: To determine whether AF catheter ablation is associated with greater improvements in markers of psychological distress compared with medical therapy alone. Design, Setting, and Participants: The Randomized Evaluation of the Impact of Catheter Ablation on Psychological Distress in Atrial Fibrillation (REMEDIAL) study was a randomized trial of symptomatic participants conducted in 2 AF centers in Australia between June 2018 and March 2021. Interventions: Participants were randomized to receive AF catheter ablation (n = 52) or medical therapy (n = 48). Main Outcomes and Measures: The primary outcome was Hospital Anxiety and Depression Scale (HADS) score at 12 months. Secondary outcomes included follow-up assessments of prevalence of severe psychological distress (HADS score >15), anxiety HADS score, depression HADS score, and Beck Depression Inventory-II (BDI-II) score. Arrhythmia recurrence and AF burden data were also analyzed. Results: A total of 100 participants were randomized (mean age, 59 [12] years; 31 [32%] women; 54% with paroxysmal AF). Successful pulmonary vein isolation was achieved in all participants in the ablation group. The combined HADS score was lower in the ablation group vs the medical group at 6 months (8.2 [5.4] vs 11.9 [7.2]; P =.006) and at 12 months (7.6 [5.3] vs 11.8 [8.6]; between-group difference, −4.17 [95% CI, −7.04 to −1.31]; P =.005). Similarly, the prevalence of severe psychological distress was lower in the ablation group vs the medical therapy group at 6 months (14.2% vs 34%; P =.02) and at 12 months (10.2% vs 31.9%; P =.01), as was the anxiety HADS score at 6 months (4.7 [3.2] vs 6.4 [3.9]; P =.02) and 12 months (4.5 [3.3] vs 6.6 [4.8]; P =.02); the depression HADS score at 3 months (3.7 [2.6] vs 5.2 [4.0]; P =.047), 6 months (3.4 [2.7] vs 5.5 [3.9]; P =.004), and 12 months (3.1 [2.6] vs 5.2 [3.9]; P =.004); and the BDI-II score at 6 months (7.2 [6.1] vs 11.5 [9.0]; P =.01) and 12 months (6.6 [7.2] vs 10.9 [8.2]; P =.01). The median (IQR) AF burden in the ablation group was lower than in the medical therapy group (0% [0%-3.22%] vs 15.5% [1.0%-45.9%]; P <.001). Conclusion and Relevance: In this trial of participants with symptomatic AF, improvement in psychological symptoms of anxiety and depression was observed with catheter ablation, but not medical therapy. Trial Registration: ANZCTR Identifier: ACTRN12618000062224 This randomized clinical trial evaluates the prevalence of psychological distress in participants referred for atrial fibrillation treatment. [ABSTRACT FROM AUTHOR]

Objective: Sudden cardiac death (SCD) and malignant ventricular arrhythmia (VA) are increasingly recognized as important issues for people living with a Fontan circulation, but data are lacking. We sought to characterize the cohort who had sudden cardiac death, most likely related to VA and/or documented VA in the Australia and New Zealand Fontan Registry including risk factors and clinical outcomes. Methods: A retrospective cohort study was performed. Inclusion criteria were documented non-sustained ventricular tachycardia, sustained ventricular tachycardia, ventricular fibrillation, resuscitated cardiac arrest or SCD > 30 days post-Fontan completion. Results: Of 1611 patients, 20 (1.2%) had VA; 14 (1.0%) had VA without SCD and 6 (<1%) had SCD (6% of all deaths recorded in Registry; 5 of those had documented VA at the time of arrest and 1 was presumed to be VA-associated). The median age at first VA was 20.5 (14–32) years, 10 (50%) were females, and the median age at Fontan operation was 8 (4–17) years. On univariable analysis, hypoplastic left heart syndrome (p = 0.03) and older age Fontan operation (p < 0.001) were associated with VA. Earlier Fontan era (p < 0.003), atriopulmonary Fontan (p < 0.001), pre-Fontan atrioventricular valve repair (p = 0.013) pre- or post-Fontan atrial arrhythmia (p = 0.010) were associated with SCD. Patients with VA had a 3 times higher risk of death or heart transplant (HR 3.27(1.19, 8.98), p = 0.02). Conclusions: A proportion of people living with a Fontan circulation have malignant VA. Routine VA screening in this cohort is essential. More data are needed to aid risk stratification. [ABSTRACT FROM AUTHOR]

Objectives: We sought to define the rate of unexpected death from acute coronary syndrome or arrhythmia in chest pain patients directly discharged from the ED. Methods: Retrospective audit of all chest pain patients at a tertiary ED for 7 years. Medical and post‐mortem records of the deceased were reviewed with independent cardiologist adjudication to determine outcomes. Primary outcome measure was 28‐day unexpected death secondary to acute coronary syndrome or arrhythmia. Results: During the study period, 25 924 patients presented with chest pain, 292 (1.1%, 95% confidence interval [CI] 0.99–1.01%) died within 28 days. Of these, 16 680(64%, 95% CI 63.88–64.12%) were discharged by ED, two (0.01%, 95% CI 0–0.011%) of this group died from the primary outcome. Conclusion: Unexpected death is very uncommon after ED discharge of chest pain patients. [ABSTRACT FROM AUTHOR]

Background: Since the last formal publication reporting on the findings of the Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) database on surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) in 2016, transcatheter approaches have become common practice. There has been an increase in use of TAVR following large, randomised control trials that only report on short-term outcomes in a selective cohort. This study aims to report on primary outcome measures and identify complications associated with SAVR and TAVR from a large national database.Methods: From the ANZSCTS database (2001-19), 14,097 SAVR and 1,194 TAVR patients were identified with clinical details and 30-day follow-up available. The primary endpoint was the composite of all-cause mortality and/or permanent stroke at 30 days. Secondary endpoints were post-procedure complications requiring treatment. Logistical regression followed by propensity score matching was performed.Results: Using logistical regression when all patient factors considered for all patients who had SAVR and TAVR, the only preoperative factors that had an impact on 30-day mortality was cerebrovascular disease, respiratory disease, preoperative dialysis, angina, and hypertension. Primary outcome 30-day mortality rate was 1.83% in the SAVR group, and 1.68% in patients in the TAVR group, p=0.7001, and permanent stroke was seen in 1.07% patients in the SAVR group, and 1.26% patients in the TAVR group. Acute limb ischaemia, aortic dissection, ventricular tachycardia, bradyarrhythmia and heart block were more common following TAVR (p<0.001), while reintubation and atrial arrhythmia were more common following SAVR (p<0.001).Conclusions: In the real world SAVR and TAVR have been used in very different patient groups and it is difficult to compare as different baseline characteristics and complications. The two patient groups maintain similarities in primary and secondary endpoints, but differences in life threatening and life altering morbidity remains significant. Collection of SAVR and TAVR data in a combined database may help to better capture and compare these complications and institute strategies to prevent them. [ABSTRACT FROM AUTHOR]

Objectives: Describe the incidence of cardiac complications in patients admitted to hospital with COVID-19 in Australia.Design: Observational cohort study.Setting: Twenty-one (21) Australian hospitals.Participants: Consecutive patients aged ≥18 years admitted to hospital with laboratory confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.Main Outcome Measures: Incidence of cardiac complications.Results: Six-hundred-and-forty-four (644) hospitalised patients (62.5±20.1 yo, 51.1% male) with COVID-19 were enrolled in the study. Overall in-hospital mortality was 14.3%. Twenty (20) (3.6%) patients developed new atrial fibrillation or flutter during admission and 9 (1.6%) patients were diagnosed with new heart failure or cardiomyopathy. Three (3) (0.5%) patients developed high grade atrioventricular (AV) block. Two (2) (0.3%) patients were clinically diagnosed with pericarditis or myopericarditis. Among the 295 (45.8%) patients with at least one troponin measurement, 99 (33.6%) had a peak troponin above the upper limit of normal (ULN). In-hospital mortality was higher in patients with raised troponin (32.3% vs 6.1%, p<0.001). New onset atrial fibrillation or flutter (6.4% vs 1.0%, p=0.001) and troponin elevation above the ULN (50.3% vs 16.4%, p<0.001) were more common in patients 65 years and older. There was no significant difference in the rate of cardiac complications between males and females.Conclusions: Among patients with COVID-19 requiring hospitalisation in Australia, troponin elevation was common but clinical cardiac sequelae were uncommon. The incidence of atrial arrhythmias and troponin elevation was greatest in patients 65 years and older. [ABSTRACT FROM AUTHOR]

Despite changes in antiarrhythmic drug (AAD) choice in patients with atrial fibrillation (AF), trends in AAD prescribing remain not investigated. We aimed to examine these changes using a nationwide Australian general practice data from 2009 to 2018. Over the 10 years, AAD prescribing in patients with AF decreased, which was mainly due to a reduction in the use of amiodarone, sotalol and digoxin. In contrast, the use of beta‐blockers and flecainide increased. [ABSTRACT FROM AUTHOR]

Background: Atrial arrhythmias are relatively common following lung transplantation and confer considerable perioperative risk, specifically haemodynamic instability, pulmonary congestion, dyspnoea, and can mask other post-transplant complications such as infection or acute rejection. However, for most patients, arrhythmias are limited to the short-term perioperative period.Methods: We present a retrospective case-control analysis of 200 lung transplant recipients and using multivariate regression analysis, document the present incidence, risk factors, and outcomes between the two groups.Results: Twenty-five per cent (25%) of lung transplantation patients developed atrial flutter or fibrillation, most frequently at day 5-7 post lung transplantation, and more commonly present in older recipients and those with underlying chronic obstructive pulmonary disease (COPD), but not in those with previously noted structural heart disease, or in those undergoing single rather than double lung transplants. Atrial arrhythmias were associated with increased intensive care unit and overall length of stay, but were not associated with increased risk of in-hospital stroke, or mortality. Based on our experience, we propose a suggested management algorithm for pharmacological and mechanical rate/rhythm control strategies, for anticoagulation, and discuss the appropriate duration of treatment.Conclusions: Atrial arrhythmias are relatively common post lung transplantation. Carefully managed, the associated risk of perioperative morbidity and mortality can be mitigated. Further prospective studies are required to validate these strategies. [ABSTRACT FROM AUTHOR]

Background: Women experience less appropriate implantable cardioverter-defibrillator (ICD) interventions and are underrepresented in randomised ICD trials. Sex-differences in inducible and spontaneous ventricular tachycardia/fibrillation (VT/VF), cardiac arrest and sudden cardiac death (SCD) early post-myocardial infarction (MI) require further study.Methods: Consecutive ST-elevation MI patients with left ventricular ejection fraction (LVEF)≤40% underwent electrophysiology study (EPS) to target early prevention of SCD. An ICD was implanted for a positive (inducible monomorphic VT) but not a negative (no arrhythmia or inducible VF) EPS. The combined primary endpoint of VT/VF (spontaneous or ICD-treated), cardiac arrest or SCD was assessed using competing risk survival analysis in women versus men with adjustment for confounders. Logistic regression was used to determine independent predictors of inducible VT at EPS.Results: A total of 403 patients (16.9% female) underwent EPS. Women were significantly older than men but with similar LVEF (31.5 ± 6.3 versus 31.6 ± 6.4%, p = 0.91). Electrophysiology study was positive for inducible VT in 22.1% and 33.4% (p = 0.066) and an ICD implanted in 25.0% and 33.4% (p = 0.356) of women versus men. Appropriate ICD activations (VT/VF) occurred in 5.9% of women and 36.6% of men (p = 0.012). The adjusted cumulative primary endpoint incidence was significantly lower in women than men (1.6% versus 26.5%, p = 0.03). Female sex was not an independent predictor of inducible VT at EPS (HR 0.63, 95% CI 0.33-1.23, p = 0.178).Conclusions: Women with early post-MI cardiomyopathy had lower VT/VF, cardiac arrest and SCD, compared to men. In ICD recipients the rate of appropriate activations was six-fold less in women compared to men. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic poses a significant stress on health resources in Australia. The Heart Rhythm Council of the Cardiac Society of Australia and New Zealand aims to provide a framework for efficient resource utilisation balanced with competing risks when appropriately treating patients with cardiac arrhythmias. This document provides practical recommendations for the electrophysiology (EP) and cardiac implantable electronic devices (CIED) services in Australia. The document will be updated regularly as new evidence and knowledge is gained with time. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) and other arrhythmias are prevalent and often encountered by general practitioners (GPs). In response to the growing prevalence and to assist practitioners in the diagnosis and management of AF, the Cardiac Society of Australia & New Zealand and Heart Foundation of Australia published the first Australian AF Guidelines in 2018. We aimed to examine (a) the proportion of GPs who performed any form of AF screening and identify the methods they applied, (b) GPs' awareness of the AF Guidelines and approaches to arrhythmia screening, (c) the roles of conventional 12-lead ECG and mobile health devices, and (d) GPs' confidence in ECG interpretation and need for training. Methods: A cross-sectional online survey titled "GPs Screen their patients for Atrial Fibrillation and othEr aRrhythmia (GPSAFER)" was conducted from October 2018 to March 2019. The participants were recruited via various GP networks across Australia. Ethics approval was granted by The University of Sydney. Results: A total of 463 surveys were completed. Many GPs (394/463, 85.1%, 95% CI 81.5–88.2%) performed some forms of AF screening and applied at least one AF screening method, most frequently pulse palpation (389/463, 84.0%). Some (299/463, 64.6%) GPs considered assessing their patients for other arrhythmias (237/299, 79.3% for complete heart block and 236/299, 78.9% for long-QT). Most GPs (424/463, 91.6%) were not using mobile ECG devices in their practice but some (147/463, 31.7%) were contemplating it. One third (175/463, 37.8%) of GPs were aware of the Australian AF Guidelines; those aware were more likely to perform AF screening (98.9% vs 76.7%, p < 0.001). Factors significantly and positively associated with AF screening were "awareness of the AF Guidelines" (p < 0.001), "number of years working in general practice" (p < 0.001), and "confidence in ECG interpretation of AF" (p = 0.003). Most GPs reported that they were very or extremely confident in interpreting AF (381/463, 82.3%) and complete heart block (266/463, 57.5%). Many GPs (349/463, 75.4%) would like to receive online ECG interpretation training. Conclusions: Assessment of arrhythmias is common in general practice and GPs are open to further training in ECG interpretation and using mobile ECG devices to aid their clinical practice. Increasing awareness of AF Guidelines and improving confidence in ECG interpretation may increase AF screening. [ABSTRACT FROM AUTHOR]

Abstract Background The need for permanent pacing has been identified as a predictor of poor outcomes in the late survivors of Fontan surgery. However, it is not clear if the need for a pacemaker is a surrogate marker of a declining Fontan state, or if pacing is deleterious to the Fontan circulation. Objectives We sought to compare the long-term outcomes of propensity-matched Fontan patients with and without a permanent pacemaker. Methods Patients who have survived Fontan completion with a documented history of cardiac arrhythmia were identified from the Australia and New Zealand Fontan Registry. Pacemaker insertion details, cardiac function and electrophysiological data were obtained for the patients with a permanent pacemaker. Survival analysis was performed with propensity score matching to compare late survival and outcomes in patients with versus without a pacemaker. Results There was a total of 310 patients with a history of cardiac arrhythmia, of which 126 (41%) had a permanent pacemaker. After propensity-score matching, 99 pairs were generated (n = 198). Patients with a permanent pacemaker had a higher risk of death (HR 3.32 95% CI 1.60–6.90, p = 0.001) and death or transplantation (HR 3.55 95% CI 1.87–6.73, p < 0.001). Patients who were only paced atrially were not at a significantly increased risk of death or transplantation. However, patients who were ventricular paced >50% of the time were much more likely to encounter late death or transplantation (HR 3.82 95% CI 1.64–8.95, p = 0.002). Conclusions Having a permanent pacemaker and needing ventricular pacing is likely associated with an increased risk of death and transplantation in patients with a Fontan circulation. Highlights • 8% of patients living with a Fontan circulation needed insertion of a permanent pacemaker. • After propensity-score matching, patients with a permanent pacemaker had a higher risk of death and transplantation compared to those without. • Patients who had ventricular pacing more than 50% of the time were at highest risk of death and transplantation, and systemic ventricular dysfunction. [ABSTRACT FROM AUTHOR]

While implantable cardioverter defibrillators decrease mortality in high risk groups of patients who have ventricular arrhythmias, antiarrhythmic drugs are still required to reduce the burden of both benign and life-threatening arrhythmias. This review will address the available medical therapy for ventricular arrhythmias in Australia and their use in different clinical situations. [ABSTRACT FROM AUTHOR]

Background: The BioMonitor 2 Pilot Study assessed the implantation procedure, the sensing amplitude and the remote monitoring transmission success rate of the second generation implantable cardiac monitor, the BioMonitor 2 (Biotronik, Berlin, Germany).Methods: This was a prospective, multi-centre, single-arm, non-randomised study involving seven operators in five sites across Australia. Data were collected at implantation, during clinic visits at 1 week and 1 month post-implantation, and through wireless remote monitoring.Results: Thirty patients with indications for long-term cardiac monitoring underwent successful insertion of a study device. The median implantation time was 9 minutes (interquartile range (IQR) 5-14 mins). The mean R-wave amplitude at 1 week was 0.75±0.39mV and remained stable over the follow-up period. Within 1 day, 97% of the patients connected to the remote monitoring network and daily messages were transmitted on 93.8% of all study days. Seventy-six per cent of patients transmitted at least one subcutaneous ECG (sECG), with a median number of sECGs per patient of seven (IQR 3-37) within 28 days.Conclusions: The results of the BioMonitor 2 Pilot study confirm the excellent sensing amplitudes afforded by this new device and the utility of the implantation tools and technique. Patient compliance with and the transmission success rate of the home monitoring system were excellent. [ABSTRACT FROM AUTHOR]

• Combination of non-targeted technique and census data in wastewater analysis. • Wastewater biomarkers of socioeconomic characteristics of societies were identified. • PPG and PEG were positively correlated with housing and occupation disadvantage. • Public health inequalities in different areas and socioeconomic groups were found. Analysis of untreated municipal wastewater is recognized as an innovative approach to assess population exposure to or consumption of various substances. Currently, there are no published wastewater-based studies investigating the relationships between catchment social, demographic, and economic characteristics with chemicals using advanced non-targeted techniques. In this study, fifteen wastewater samples covering 27% of the Australian population were collected during a population Census. The samples were analysed with a workflow employing liquid chromatography high-resolution mass spectrometry and chemometric tools for non-target analysis. Socioeconomic characteristics of catchment areas were generated using Geospatial Information Systems software. Potential correlations were explored between pseudo-mass loads of the identified compounds and socioeconomic and demographic descriptors of the wastewater catchments derived from Census data. Markers of public health (e.g., cardiac arrhythmia, cardiovascular disease, anxiety disorder and type 2 diabetes) were identified in the wastewater samples by the proposed workflow. They were positively correlated with descriptors of disadvantage in education, occupation, marital status and income, and negatively correlated with descriptors of advantage in education and occupation. In addition, markers of polypropylene glycol (PPG) and polyethylene glycol (PEG) related compounds were positively correlated with housing and occupation disadvantage. High positive correlations were found between separated and divorced people and specific drugs used to treat cardiac arrhythmia, cardiovascular disease, and depression. Our robust non-targeted methodology in combination with Census data can identify relationships between biomarkers of public health, human behaviour and lifestyle and socio-demographics of whole populations. Furthermore, it can identify specific areas and socioeconomic groups that may need more assistance than others for public health issues. This approach complements important public health information and enables large-scale national coverage with a relatively small number of samples. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the benefits of a strategy of early Fontan conversion. METHODS: Using the Australia and New Zealand Fontan Registry, retrospective analysis of their long-term follow-up data was performed. RESULTS: Between 1990 and 2014, a total of 39 patients underwent surgical conversion in 6 centres at a median age of 23.8 years (IQR: 19.3–28.2), 18.7 ± 5.0 years post-Fontan. One centre tended to perform conversion earlier: interval since first documented arrhythmia 2.9 ± 4.0 vs 4.0 ± 4.2 years, average NYHA Class 2 ± 0.4 vs 3 ± 0.9 (P = 0.008), mean number of preop anti-arrhythmics 1 ± 0.4 vs 2 ± 0.6 (P = 0.05). Two patients underwent conversion to an extracardiac conduit only, while 36 had concomitant right atrial cryoablation, of which 16 also had pacemaker implantation. Nine patients suffered major cardiac-related complications (7 low output syndrome, 3 ECMO, 3 acute renal failure, one stroke) (2/17 from the early conversion centre and 7/22 of the others; P = 0.14). Four patients died in hospital (10.3%) and 4 late after a median of 0.9 years [95% confidence interval (CI): 0.5–1] after conversion. An additional 2 patients needed transplantation at 1 and 8.8 years after conversion, respectively. The 10-year freedom from heart transplantation was 86% (95% CI: 51–97%). Outcomes from the centre with an early conversion strategy were significantly better: 8-year freedom from death or heart transplantation was 86% (95% CI: 53–96) vs 51% (95% CI: 22–74; log-rank P = 0.007). Eight additional patients required pacemaker implantation and 5 had arrhythmia recurrence. CONCLUSIONS: Fontan conversion is associated with lasting survival outcomes up to 10 years after conversion. A strategy of surgical conversion at earlier stage of failure may be associated with better survival free from transplantation. [ABSTRACT FROM AUTHOR]

Several studies have shown that postoperative atrial fibrillation (POAF) is associated with poorer short- and long-term outcomes after isolated coronary artery bypass grafting surgery. Nevertheless, there is considerable debate as to whether this reflects an independent association of POAF with poorer outcomes or confounding by other factors. We sought to investigate this issue. Data obtained from June 2001 through December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program were retrospectively analyzed. Demographic and operative data were compared between patients who developed POAF and those who did not using chi-square and t tests. The independent impact of POAF on 14 short-term complications and long-term mortality was determined using binary logistic and Cox regression, respectively. Excluding patients with preoperative arrhythmia, isolated coronary artery bypass grafting surgery was performed in 19,497 patients. Of these, 5,547 (28.5%) developed POAF. Patients with POAF were generally older (mean age 69 vs 65 years, p <0.001) and presented more often with co-morbidities including congestive heart failure (p <0.001), hypertension (p <0.001), cerebrovascular disease (p <0.001), and renal failure (p = 0.046). Patients with POAF demonstrated a greater 30-day mortality on univariate analysis but not on multivariate analysis (p = 0.376). Patients with POAF were, however, at an independently increased risk of perioperative complications including permanent stroke (p <0.001), new renal failure (p <0.001), infective complications (p <0.001), gastrointestinal complications (p <0.001), and return to the theater (p <0.001). POAF was also independently associated with shorter long-term survival (p = 0.002). In conclusion, POAF is a risk factor for short-term morbidity and decreased long-term survival. Rigorous evaluation of various therapies that prevent or decrease the impact of POAF is imperative. Moreover, patients who develop POAF should undergo strict surveillance and be routinely screened for complications after discharge. [ABSTRACT FROM AUTHOR]

The development of cardiac control in association with terrestrial respiration patterns was examined throughout the period of maternal dependence in Australian fur seal pups. Resting eupnoic heart rate and respiration rate were significantly correlated ( r2 = 0.49) and both decreased with age ( P < 0.05 in both cases). From an early age (1 month), pups displayed terrestrial apnoeas (18.1 ± 0.5 s) accompanied by substantial bradycardia (127 beats min−1, a 13% decrease from eupnoic HR). Terrestrial apnoea duration increased significantly with age reaching a mean of 41 s just prior to weaning, slightly lower than the mean dive duration (52 s) previously recorded for pups of the same age. Correspondingly, mean apnoic heart rate decreased with age to 74 beats min−1 just prior to weaning, representing a 25% decrease on eupnoic heart rate. Importantly, concomitant with the decrease in mean apnoic heart rate with age, an increase in the control of bradycardia was evident with the variability in instantaneous apnoic heart decreasing such that older pups were able to maintain a low steady heart rate for the duration of the apnoea. The changes seen in these parameters are similar to those reported during postnatal development in elephant seals ( Mirounga spp.) and harbour seals ( Phoca vitulina), and are considered indicative of the development of cardiac control. These findings suggest a common strategy for the development of bradycardia control in both otariid and phocid seals. [ABSTRACT FROM AUTHOR]

Aim: Electrical burns account for up to 10% of burns admissions worldwide. Although a potentially serious mechanism of injury in children, there exists limited Australian data. This study aimed to describe the epidemiology, presentation, management and complications of electrical burn injuries in children. Methods: We performed a retrospective case note review of all children under 16 years of age with electrical burns admitted to the New South Wales Paediatric Burns Centre over an 8-year, 2-month study period between November 1995 and December 2003. Results: Twenty-two cases were identified. The mean age at presentation was 7.6 years (range 8 months to 14.3 years). Eighty-six percent of cases were sustained from a Low Voltage (<1000 W) power source and 55% occurred in males. The total body surface area burnt ranged from 0.5% to 35% with an average of 4%. Fourteen children had their burns managed non-operatively, but eight required various surgical procedures ranging from local debridement and primary closure to full-thickness skin grafting. The average length of hospital stay was 6 days (range 1–58 days). Complications occurred in 4 of the 22 patients (18%) and included wound infections, acute renal failure because of myoglobinuria, permanent electrocardiogram changes and long-term paraesthesia. Three patients (14%) suffered continued morbidity because of scarring, amputation and psychological disturbance. There was no mortality. Conclusions: Electrical injury was an infrequent but potentially serious cause of injury in children. Minor injuries were successfully managed non-operatively. Neurological sequelae, cardiac arrhythmias and renal failure remain serious complications in up to 20% of cases. [ABSTRACT FROM AUTHOR]

Evidence indicates that hospital nurse-initiated defibrillation improves survival following cardiac arrest. Accordingly, hospitals are changing their policies to permit nurses to initiate defibrillation. However, if nurse-initiated defibrillation is to be successful implemented, nurses' beliefs about this practice need to be understood. Therefore, the aim of this study was to explore the attitudes of rural nurses towards defibrillation to assist in the development of nurse-initiated defibrillation programmes. This cross-sectional study examined the defibrillation beliefs of registered nurses in rural areas. A proportionally stratified sample of registered nurses (n = 436) were drawn from 51 rural acute care hospitals in Australia. Most (n = 224; 52%) of the participants were not permitted to initiate defibrillation. A one-way between-groups multivariate analysis of variance showed that nurses who were permitted to initiate defibrillation held stronger positive beliefs towards defibrillation than nurses not permitted (10,410) = 13.88, p < 0.001. Nurses not permitted were more concerned about the challenge of learning rhythms, incurring litigation and harming the patient or themselves. If it is accepted that defibrillation will become an essential part of all nurses' roles, these beliefs should be explored and integrated into educational programmes as inappropriate beliefs about defibrillation may impede implementation and skills development. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The goal of this study was to estimate the associations between outdoor air pollution and cardiovascular hospital admissions for the elderly. DESIGN: Associations were assessed using the case-crossover method for seven cities: Auckland and Christchurch, New Zealand; and Brisbane, Canberra, Melbourne, Perth, and Sydney Australia. Results were combined across cities using a random-effects meta-analysis and stratified for two adult age groups: 15–64 years and ≥ 65 years of age (elderly). Pollutants considered were nitrogen dioxide, carbon monoxide, daily measures of particulate matter (PM) and ozone. Where multiple pollutant associations were found, a matched case-control analysis was used to identify the most consistent association. RESULTS: In the elderly, all pollutants except O3 were significantly associated with five categories of cardiovascular disease admissions. No associations were found for arrhythmia and stroke. For a 0.9-ppm increase in CO, there were significant increases in elderly hospital admissions for total cardiovascular disease (2.2%), all cardiac disease (2.8%), cardiac failure (6.0%), ischemic heart disease (2.3%), and myocardial infarction (2.9%). There was some heterogeneity between cities, possibly due to differences in humidity and the percentage of elderly people. In matched analyses, CO had the most consistent association. CONCLUSIONS: The results suggest that air pollution arising from common emission sources for CO, NO2, and PM (e.g., motor vehicle exhausts) has significant associations with adult cardiovascular hospital admissions, especially in the elderly, at air pollution concentrations below normal health guidelines. RELEVANCE TO CLINICAL AND PROFESSIONAL PRACTICE: Elderly populations in Australia need to be protected from air pollution arising from outdoor sources to reduce cardiovascular disease. [ABSTRACT FROM AUTHOR]

Abstract The National Heart Foundation of Australia recognizes that the risk of lethal arrhythmias is greater very early after the onset of myocardial infarction and that the more promptly flow can be restored in the infarct-related artery the greater will be the benefits for survival and preservation of heart function. The Heart Foundation has therefore conducted several public media campaigns to encourage patients to seek help more promptly and evaluated their impact. Since 1996, we have conducted four surveys of delays preceding admission of patients to coronary care units throughout Australia to assess the impact of the Heart Foundation's media campaigns. Data were collected on 1665 patients who presented to 73 hospitals; information on patient delay was available for 1178 of them. There were no significant differences in patient delay (median 1.5–2.0 h) in the four surveys from 1996 to 2002, nor when patients were categorized by age, sex, presenting diagnosis or history of previous myocardial infarction or coronary revascularization by percutaneous or surgical techniques. New approaches are needed to reduce patient-related delay after the onset of symptoms suggesting possible myocardial infarction. (Intern Med J 2005; 35: 279–282) [ABSTRACT FROM AUTHOR]

Background: Tobacco smoking is a leading cause of cardiovascular disease (CVD) morbidity and mortality. Evidence on the relation of smoking to different subtypes of CVD, across fatal and non-fatal outcomes, is limited.Methods: A prospective study of 188,167 CVD- and cancer-free individuals aged ≥ 45 years from the Australian general population joining the 45 and Up Study from 2006 to 2009, with linked questionnaire, hospitalisation and death data up to the end of 2015. Hazard ratios (HRs) for hospitalisation with or mortality from CVD among current and past versus never smokers were estimated, including according to intensity and recency of smoking, using Cox regression, adjusting for age, sex, urban/rural residence, alcohol consumption, income and education. Population-attributable fractions were estimated.Results: During a mean 7.2 years follow-up (1.35 million person-years), 27,511 (crude rate 20.4/1000 person-years) incident fatal and non-fatal major CVD events occurred, including 4548 (3.2) acute myocardial infarction (AMI), 3991 (2.8) cerebrovascular disease, 3874 (2.7) heart failure and 2311 (1.6) peripheral arterial disease (PAD) events. At baseline, 8% of participants were current and 34% were past smokers. Of the 36 most common specific CVD subtypes, event rates for 29 were increased significantly in current smokers. Adjusted HRs in current versus never smokers were as follows: 1.63 (95%CI 1.56-1.71) for any major CVD, 2.45 (2.22-2.70) for AMI, 2.16 (1.93-2.42) for cerebrovascular disease, 2.23 (1.96-2.53) for heart failure, 5.06 (4.47-5.74) for PAD, 1.50 (1.24-1.80) for paroxysmal tachycardia, 1.31 (1.20-1.44) for atrial fibrillation/flutter, 1.41 (1.17-1.70) for pulmonary embolism, 2.79 (2.04-3.80) for AMI mortality, 2.26 (1.65-3.10) for cerebrovascular disease mortality and 2.75 (2.37-3.19) for total CVD mortality. CVD risks were elevated at almost all levels of current smoking intensity examined and increased with smoking intensity, with HRs for total CVD mortality in current versus never smokers of 1.92 (1.11-3.32) and 4.90 (3.79-6.34) for 4-6 and ≥ 25 cigarettes/day, respectively. Risks diminished with quitting, with excess risks largely avoided by quitting before age 45. Over one third of CVD deaths and one quarter of acute coronary syndrome hospitalisations in Australia aged < 65 can be attributed to smoking.Conclusions: Current smoking increases the risk of virtually all CVD subtypes, at least doubling the risk of many, including AMI, cerebrovascular disease and heart failure. Paroxysmal tachycardia is a newly identified smoking-related risk. Where comparisons are possible, smoking-associated relative risks for fatal and non-fatal outcomes are similar. Quitting reduces the risk substantially. In an established smoking epidemic, with declining and low current smoking prevalence, smoking accounts for a substantial proportion of premature CVD events. [ABSTRACT FROM AUTHOR]

Objective: To determine whether cardiac monitoring is required in children sustaining electric shock at Australian household voltage.Methodology: Records of patients admitted via the Emergency Department of Princess Margaret Hospital for Children, Perth, Australia, for the period 1968-96 were retrospectively reviewed. The initial ECG findings of patients with an electric shock were recorded, and the development of any arrhythmia.Results: Forty-four patients were identified, 40 of whom had sustained a household electrical injury. One patient had an abnormal ECG on admission, none developed an arrhythmia and all survived.Conclusions: Routine cardiac monitoring is not required after exposure to Australian household electricity supply if the child is asymptomatic and has a normal ECG on presentation. [ABSTRACT FROM AUTHOR]

Background Inpatient management of cardiac patients by cardiologists results in reduced mortality and hospitalisation. With increasing subspecialisation of the field because of growing management complexity and use of technological innovations, the impact of sub-specialisation on patient outcomes is unclear. Aim To investigate whether management by subspecialty cardiologists impacts the outcomes of patients with subspecialty-specific diseases. Methods All patients admitted to a tertiary centre over nine years with a diagnosis of heart failure, acute coronary syndrome (ACS) or primary arrhythmia were reviewed. The outcomes of these patients managed by cardiologists subspecialised in their admission diagnosis (heart failure specialists, interventionalists and electrophysiologists) were compared with those treated by general cardiologists. Results Heart failure was diagnosed in 1704 patients, ACS in 7763 and arrhythmia in 4398. There was no difference in length of stay (LOS) ( P = 0.26), mortality ( P = 0.57) or cardiovascular readmissions ( P = 0.50) in heart failure patients treated by general cardiologists compared with subspecialists. In ACS patients, subspecialty management was associated with reduced LOS, cardiovascular readmissions and mortality (all P < 0.05). This reduction in mortality was seen mainly in lower risk patients ( P < 0.05). There was a reduction in LOS and cardiovascular readmissions in arrhythmia patients receiving subspecialty management (both P < 0.05) but no difference in mortality ( P = 0.14). ACS patients managed by interventionalists were more likely to undergo coronary intervention ( P < 0.05). Electrophysiologists more frequently referred patients for catheter ablation and pacemaker implantation than general cardiologists ( P < 0.05). Conclusions The benefits of subspecialty care seem attributable to the appropriate selection of patients who would benefit from technological innovations in care. These results suggest that the development of healthcare systems which align cardiovascular disease with the subspecialist may be more effective. [ABSTRACT FROM AUTHOR]

Discusses the cardiac risk of psychotropic drugs in Australia. Risk for QT prolongation; Chronic psychosis relapse; Need for annual electrocardiographic examination.

The article presents a study that examines whether the closure of patent foramen ovale (PFO) is better than medical therapy alone for lowering recurrence after cryptogenic embolism. It discusses the methodologies used in the study including randomized controlled trial. It concludes that closure of the PFO did not lower the primary composite endpoint or its components after the cryptogenic embolism.

The graded benefit of exercise on cardiovascular risk is well established. Observational studies have, however, focused on mild to moderate levels of activity. In Australia, in excess of 30% of the adult population exercise in excess of the upper range as studied in the literature. There is limited evidence as to whether the risk/benefit ratio is maintained in those participating in regular intense exercise. Case reports and circumstantial evidence raise the possibility that more extreme exercise may have some detrimental effects. In effect, exercise may have a typical dose–response curve with a plateau or even toxicity at more extreme levels. Given the increasing popularity of endurance sporting pursuits, there is a need for further research into the cardiac adaptations and consequences of extreme habitual exercise. [Copyright &y& Elsevier]