2023 Cardiac Society of Australia and New Zealand Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation.

Catheter ablation for atrial fibrillation (AF) has increased exponentially in many developed countries, including Australia and New Zealand. This Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation from the Cardiac Society of Australia and New Zealand (CSANZ) recognises healthcare factors, expertise and expenditure relevant to the Australian and New Zealand healthcare environments including considerations of potential implications for First Nations Peoples. The statement is cognisant of international advice but tailored to local conditions and populations, and is intended to be used by electrophysiologists, cardiologists and general physicians across all disciplines caring for patients with AF. They are also intended to provide guidance to healthcare facilities seeking to establish or maintain catheter ablation for AF.

Mitral valve prolapse: arrhythmic risk during pregnancy and postpartum.

BACKGROUND AND AIMS: Arrhythmic mitral valve prolapse (AMVP) is linked to life-threatening ventricular arrhythmias (VAs), and young women are considered at high risk. Cases of AMVP in women with malignant VA during pregnancy have emerged, but the arrhythmic risk during pregnancy is unknown. The authors aimed to describe features of women with high-risk AMVP who developed malignant VA during the perinatal period and to assess if pregnancy and the postpartum period were associated with a higher risk of malignant VA. METHODS: This retrospective international multi-centre case series included high-risk women with AMVP who experienced malignant VA and at least one pregnancy. Malignant VA included ventricular fibrillation, sustained ventricular tachycardia, or appropriate shock from an implantable cardioverter defibrillator. The authors compared the incidence of malignant VA in non-pregnant periods and perinatal period; the latter defined as occurring during pregnancy and within 6 months after delivery. RESULTS: The authors included 18 women with AMVP from 11 centres. During 7.5 (interquartile range 5.8-16.6) years of follow-up, 37 malignant VAs occurred, of which 18 were pregnancy related occurring in 13 (72%) unique patients. Pregnancy and 6 months after delivery showed increased incidence rate of malignant VA compared to the non-pregnancy period (univariate incidence rate ratio 2.66, 95% confidence interval 1.23-5.76). CONCLUSIONS: The perinatal period could impose increased risk of malignant VA in women with high-risk AMVP. The data may provide general guidance for pre-conception counselling and for nuanced shared decision-making between patients and clinicians.

Temporal association between atrial fibrillation and ischemic stroke: Systematic review and meta-analysis.

BACKGROUND: Paroxysmal atrial fibrillation (PAF) is strongly associated with ischemic stroke. Continuous cardiac implantable electronic devices (CIEDs) can assess PAF episodes over prolonged periods. Studies that attempted to find a temporal association between PAF and ischemic stroke were inconclusive. Thus, we performed a systematic review and meta-analysis to assess this relationship. AIMS: This study aimed to assess the temporal association between AF episodes and stroke within 30 days of the arrhythmic episode. The secondary outcome is a temporal association within a 90-day period. SUMMARY OF REVIEW: A total of 2804 studies that discussed the temporal relationship between PAF and ischemic stroke were screened, and 7 studies were included in the meta-analysis. Among the 4041 patients included in these studies, there were 138 patients with device detected PAF episodes and stroke. Four studies used a 30-day window for temporality and the pooled odds ratio (OR) showed a significant association (OR 4.11 (95% CI 1.03-16.40)). The three studies reporting on AF and stroke within a 90-day window did not find a significant temporal relationship (OR 0.43 (95% CI 0.13-1.41)). Finally, the pooled result of those seven studies did not show a significant association (OR 1.51 (95% CI 0.44-5.17)). CONCLUSION: This meta-analysis supports a temporal relationship between PAF and ischemic stroke within a 30-day window. Establishing this relationship is important for individualized risk prediction and targeted anticoagulation treatment. DATA ACCESS STATEMENT: The data will be made available upon reasonable request.

Society for Cardiovascular Magnetic Resonance 2022 Cases of SCMR case series.

"Cases of SCMR" is a case series on the SCMR website (https://www.scmr.org) for the purpose of education. The cases reflect the clinical presentation, and the use of cardiovascular magnetic resonance (CMR) in the diagnosis and management of cardiovascular disease. The 2022 digital collection of cases are presented in this manuscript.

Incidence and progression of atrial fibrillation in patients with and without heart failure using mineralocorticoid receptor antagonists: a meta-analysis.

BACKGROUND: Mineralocorticoid receptor antagonists (MRAs) have emerged as potential therapy to target the underlying arrhythmogenic substrate in atrial fibrillation (AF). Nevertheless, there have been inconsistent results on the impact of MRAs on AF. OBJECTIVE: We sought to evaluate the effect of MRAs on AF incidence and progression in patients with and without heart failure. METHODS: Electronic databases were searched up to September, 2022 for randomized controlled trials (RCTs) that evaluated MRA use and reported AF outcomes. Primary outcome was a composite of new-onset or recurrent AF. Safety outcomes included hyperkalemia and gynecomastia risks. A random-effects meta-analysis estimated pooled odds ratios (OR) and 95% confidence intervals (CI). RESULTS: 12 RCTs, comprising 11,419 patients treated with various MRAs were included [5960 (52%) on MRA]. On follow-up (6-39 months), 714 (5.5%) patients developed AF. MRA therapy was associated with a 32% reduction in the risk of new-onset or recurrent AF [OR 0.68 (95% CI 0.51-0.92), I2 = 40%]. On subgroup analysis, the greatest benefit magnitude was demonstrated in reducing AF recurrence [OR 0.50 (95% CI 0.30-0.83)] and among patients with left ventricular dysfunction [OR 0.59 (95% CI 0.40-0.85)]. Gynecomastia, but not hyperkalemia, was associated with MRA use. Meta-regression analysis demonstrated that therapy duration was a significant interaction factor driving the effect size (Pinteraction = 0.013). CONCLUSION: MRA use is associated with a reduction in AF risk, especially AF progression. A prominent effect is seen in patients with heart failure, further augmented by therapy duration. Prospective trials are warranted to evaluate MRA use as upstream therapy for preventing this common arrhythmia.

Atrial Fibrillation Health Literacy Questionnaire (AFHLQ): The development of an AF-specific health literacy questionnaire.

Background: Health literacy is a key enabler of effective behavioural modification in chronic diseases. While patient reported outcome measures (PROMs) exists for patient with atrial fibrillation (AF), none address risk factors comprehensively. The aim of the study was to develop and qualitatively validate a disease specific PROM that incorporates knowledge on risk factors and assesses interactive and critical health literacy of people living with AF. Methods: The 47-item Atrial Fibrillation Health Literacy Questionnaire (AFHLQ) was developed and validated through a qualitative research design. Expert and Consumer focus groups, each consisting of seven participants provided opinion. Results: The 47-item questionnaire consists of 5 domains: (1) what is AF, (2) what are the symptoms of AF, (3) why do people get AF, (4) management of AF, and (5) what measures can slow or prevent the progression of AF. Recommendations resulted in several changes to the original 47 item list during the qualitative validation process: 13 original items were removed, and 13 new items were added. The response categories were also simplified from a Likert scale to "yes", "no" or "don't know". Conclusion: A 47-item AFHLQ instrument was developed and validated with modifications made through clinical expert and consumer opinion. This tool has a potential to be used to evaluate and guide interventions at a clinical and population level to understand and improve AF health literacy and outcomes.

Atherosclerosis on CT coronary angiography and the risk of long-term cardiovascular events after liver transplantation.

Computed tomography coronary angiography (CTCA) is increasingly utilized for preoperative risk stratification before liver transplantation (LT). We sought to assess the predictors of advanced atherosclerosis on CTCA using the recently developed Coronary Artery Disease-Reporting and Data System (CAD-RADS) score and its impact on the prediction of long-term major adverse cardiovascular events (MACE) following LT. We conducted a retrospective cohort study of consecutive patients who underwent CTCA for LT work-up between 2011 and 2018. Advanced atherosclerosis was defined as coronary artery calcium scores > 400 or CAD-RADS score ≥ 3 (≥50% coronary artery stenosis). MACE was defined as myocardial infarction, heart failure, stroke, or resuscitated cardiac arrest. Overall, 229 patients underwent CTCA (mean age 66 ± 5 y, 82% male). Of these, 157 (68.5%) proceeded with LT. The leading etiology of cirrhosis was hepatitis (47%), and 53% of patients had diabetes before transplant. On adjusted analysis, male sex (OR 4.6, 95% CI 1.5-13.8, p = 0.006), diabetes (OR 2.2, 95% CI 1.2-4.2, p = 0.01) and dyslipidemia (OR 3.1, 95% CI 1.3-6.9, p = 0.005) were predictors of advanced atherosclerosis on CTCA. Thirty-two patients (20%) experienced MACE. At a median follow-up of 4 years, CAD-RADS ≥ 3, but not coronary artery calcium scores, was associated with a heightened risk of MACE (HR 5.8, 95% CI 1.6-20.6, p = 0.006). Based on CTCA results, 71 patients (31%) commenced statin therapy which was associated with a lower risk of all-cause mortality (HR 0.48, 95% CI 0.24-0.97, p = 0.04). The standardized CAD-RADS classification on CTCA predicted the occurrence of cardiovascular outcomes following LT, with a potential to increase the utilization of preventive cardiovascular therapies.

Commotio Cordis in Non-Sport-Related Events: A Systematic Review.

BACKGROUND: Commotio cordis is an increasingly recognized cause of sudden cardiac death. Although commonly linked with athletes, many events occur in non-sport-related settings. OBJECTIVES: The goal of this study was to characterize and compare non-sport-related vs sport-related commotio cordis. METHODS: PubMed and Embase were searched for all cases of commotio cordis from inception to January 5, 2022. RESULTS: Of 334 commotio cordis cases identified, 121 (36%) occurred in non-sport-related contexts, which included assault (76%), motor vehicle accidents (7%), and daily activities (16%). Projectiles were implicated significantly less in non-sport-related events (5% vs 94%, respectively; P < 0.001). Nonprojectile etiologies in non-sport-related events mostly consisted of impacts with body parts (79%). Both categories affected similar younger aged demographic (P = 0.10). The proportion of female victims was significantly higher in non-sport-related events (13% vs 2%, respectively; P = 0.025). Mortality was significantly higher in non-sport-related events (88% vs 66%, respectively; P < 0.001). In non-sport-related events, rates of cardiopulmonary resuscitation (27% vs 97%, respectively; P < 0.001) and defibrillation (17% vs 81%, respectively; P < 0.001) were both lower and resuscitation was more commonly delayed beyond 3 min (80% vs 5%, respectively; P < 0.001). CONCLUSIONS: Commotio cordis occurs across a spectrum of non-sport-related settings including assault, motor vehicle accidents, and daily activities. Both categories affected a younger and male-predominant demographic. Mortality is higher in non-sport-related commotio cordis, likely owing to lower rates of cardiopulmonary resuscitation, defibrillation, automated external defibrillator availability, and extended time to resuscitation. Increased awareness of non-sport-related commotio cordis is essential to develop a means of prevention and mortality reduction, with earlier recognition and prompt resuscitation measures.

High Incidence of Autonomic Dysfunction and Postural Orthostatic Tachycardia Syndrome in Patients with Long COVID: Implications for Management and Health Care Planning.

BACKGROUND: Autonomic dysfunction, including postural orthostatic tachycardia syndrome (POTS), has been reported in individuals with post-acute sequelae of COVID-19 (PASC). However, the degree of dysautonomia in PASC has not been compared to those with POTS and healthy controls. METHODS: All participants were prospectively enrolled between August 5, 2021 and October 31, 2022. Autonomic testing included beat-to-beat hemodynamic monitoring to assess respiratory sinus arrhythmia, Valsalva ratio, and orthostatic changes during a 10-minute active standing test, as well as sudomotor assessment. The Composite Autonomic Symptom Score (COMPASS-31) was used to assess symptoms and the EuroQuol 5-Dimension survey (EQ-5D-5L) was used to assess health-related quality of life (HrQoL) measures. RESULTS: A total of 99 participants (n = 33 PASC, n = 33 POTS, and n = 33 healthy controls; median age 32 years, 85.9% females) were included. Compared with healthy controls, the PASC and POTS cohorts demonstrated significantly reduced respiratory sinus arrhythmia (P < .001), greater heart rate increase during 10-minute active standing test (P < .001), greater burden of autonomic dysfunction evidenced by higher COMPASS-31 scores across all subdomains (all P < .001), and poor HrQoL across all EQ-5D-5L domains (all P < .001), lower median EuroQol-visual analogue scale (P < .001), and lower utility scores (P < .001). The majority (79%) of those with PASC met the internationally established criteria for POTS. CONCLUSION: The prevalence of autonomic symptomology for POTS was high in those with PASC, leading to poor HrQoL and high health disutility. Autonomic testing should be routinely undertaken in those with PASC to aid diagnosis and direct appropriate management to improve health outcomes.

Improved outcomes of conduction system pacing in heart failure with reduced ejection fraction: A systematic review and meta-analysis.

Conduction system pacing (CSP)-His bundle pacing (HBP) and left bundle branch area pacing (LBBAP)-are emerging alternatives to biventricular pacing (BVP) for cardiac resynchronization therapy (CRT) in heart failure. However, evidence is largely limited to small and observational studies. We conducted a meta-analysis including a total of 15 randomized controlled trials (RCTs) and non-RCTs that compare CSP (HBP and LBBAP) with BVP in patients with CRT indications. We assessed the mean differences in QRS duration (QRSd), pacing threshold, left ventricular ejection fraction (LVEF), and New York Heart Association (NYHA) class score. CSP resulted in a pooled mean QRSd improvement of -20.3 ms (95% confidence interval [CI] -26.1 to -14.5 ms; P < .05; I2= 87.1%) vs BVP. For LVEF, a weighted mean increase of 5.2% (95% CI 3.5%-6.9%; P < .05; I2 = 55.6) was observed after CSP vs BVP. The mean NYHA score was reduced by -0.40 (95% CI -0.6 to -0.2; P < .05; I2 = 61.7) after CSP vs BVP. A subgroup analysis of outcomes stratified by LBBAP and HBP demonstrated statistically significant weighted mean improvements of QRSd and LVEF with both CSP modalities compared with BVP. LBBAP resulted in NYHA improvement compared with BVP, without differences between CSP subgroups. LBBAP is associated with a significantly lowered mean pacing threshold of -0.51 V (95% CI -0.68 to -0.38 V) while HBP had increased the mean threshold (0.62 V; 95% CI -0.03 to 1.26 V) compared with BVP; however, this was associated with significant heterogeneity. Overall, both CSP techniques are feasible and effective CRT alternatives for heart failure. Further RCTs are needed to establish long-term efficacy and safety.

Development of a carpark cardiac implantable electronic device clinic to improve time efficiency and patient satisfaction in the context of restrictions imposed by the COVID-19 pandemic.

INTRODUCTION: We evaluated time efficiency and patient satisfaction of a "car park clinic" (CPC) compared to traditional face-to-face (F2F) during the COVID-19 pandemic. METHODS: Consecutive patients attending CPC between September 2020 and November 2021 were surveyed. CPC time was recorded by staff. F2F time was reported by patients and administrative data. RESULTS: A total of 591 patients attended the CPC. A total of 176 responses were collected for F2F clinic. Regarding satisfaction, 90% of CPC patients responded "happy" or "very happy." 96% reported feeling "safe" or "very safe." Patients spent significantly less time in CPC compared to F2F (17 ± 8 vs. 50 ± 24 min, p < .001). CONCLUSION: CPC had excellent patient satisfaction and superior time efficiency compared to F2F.

Ventricular fibrillation episodes related to managed ventricular pacing algorithm in a patient with mitral valve prolapse - "Arrhythmic MVP due to MVP".

We report a case of an implant cardiac defibrillator (ICD) patient who an ICD implanted for ventricular fibrillation (VF) related to mitral valve prolapse. He has 2 episodes of VF in his device lives. First episode of VF in year 2016 was initiated after a pause related to the MVP™ algorithm with a critically timed PVC. MVP™ was turned off which prevented further VF episodes. However, MVP™ was turned back on at the device replacement in 2018. A second VF episode developed with similar mechanism in 2021 and MVP™ was subsequently turned off with no further VF recorded. This case highlights the importance of recognizing the mechanism of initiation of tachy-arrhythmia episodes and serves as an important reminder regarding optimization of device settings at the time of replacement.

Late recurrence of atrial fibrillation and flutter in patients referred for elective electrical cardioversion.

Aim    The primary aim was to ascertain long-term rates of atrial fibrillation (AF) recurrence in this all-comer patient population undergoing elective electrical cardioversion (DCR). Secondary aims included procedural DCR success, clinical predictors of long-term maintenance of sinus rhythm (SR) and AF related hospitalizations.Material and Methods    A retrospective cohort study was conducted. Consecutive patients (n=316) undergoing elective DCR were included.Results    Successful immediate reversion to SR was attained in 266 (84 %) of patients. 224 (84 %) patients were followed up for a median period of 3.5 years (IQR 2.7-4.3). Most patients (150 [67 %]) had recurrence of AF / flutter at a median time of 240 days. Clinical predictors of AF recurrence included a history of AF (HR 0.63, p=0.038) and a dilated left atrium (HR 4.13, p=0.048). Maintenance of SR was associated with fewer unplanned hospitalizations for AF (HR 3.25, p<0.01).Conclusion    There was high procedural success post DCR. However, long-term rates of AF recurrence were high, and AF recurrences were associated with increased hospitalizations. These findings underscore the importance of clinical vigilance and multi-modal management as part of a comprehensive and effective rhythm control strategy.

Sudden cardiac death related to physical exercise in the young: a nationwide cohort study of Australia.

BACKGROUND: Sudden cardiac death (SCD) during physical exercise is devastating. AIMS: To evaluate causes and circumstances of exercise-related SCD in the young in Australia. METHODS: We reviewed the National Coronial Information System database for deaths in Australia relating to cardiovascular disease in cases aged 10-35 years between 2000 and 2016. Cases who had undertaken physical exercise at the time of the event were included. We collected demographics, circumstances of death, type of physical exercise, bystander cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use prior to ambulance arrival. RESULTS: Over a 17-year period, 1925 SCD cases were identified, of which 110 (6%) cases (median age 27 years (interquartile range 21-32 years); 92% male) were related to sports/physical exercise. Thirteen (12%) cases occurred in active athletes. Most common causes were coronary artery disease (CAD; 37%) and sudden arrhythmic death syndrome (SADS; 20%). Among Aboriginal and Torres Strait Islanders (n = 10), all deaths were related to CAD. Australian Rules Football (24%), running/jogging (14%) and soccer (14%) were the most frequent physical exercise activities. Prior symptoms were present in 39% (chest pain 37%, pre-syncope/syncope 26%). Most (87%) were witnessed, with bystander CPR in 70%. AED use prior to ambulance arrival was 8%. CONCLUSIONS: The present study demonstrates the high occurrence of CAD and SADS in SCD in the young related to physical exercise. Aboriginal and Torres Strait Islanders were disproportionately affected by CAD. Although events were commonly witnessed, AED was seldom used prior to ambulance arrival and highlights an important opportunity to improve outcomes in the post-arrest chain of survival.

Atrial Tachyarrhythmias and Stroke: Temporal Relationship and Stroke Subtypes.

BACKGROUND AND PURPOSE: Research into the temporal relationship between atrial tachyarrhythmias (atrial tachycardia [AT] and atrial fibrillation [AF]) and stroke has produced conflicting findings. Systematic categorization of stroke subtypes may help clarify the discussion. OBJECTIVES: The objective of the study was to examine the presence and timing of AT/AF in relation to ischemic stroke subtypes, categorized as either cardioembolic (CE) or non-CE. METHODS: Consecutive patients presenting to the Austin Hospital with acute stroke from 2012 to 2019 and a cardiac implantable electronic device (CIED) were identified. Using a case-control design, the temporal proximity of AT/AF episodes in the 90 days prior to stroke was compared in the CE and non-CE stroke groups. RESULTS: 5,591 patients presented to the Austin Hospital with acute stroke from 2012 to 2019, of whom 31 patients with an ischemic stroke and a CIED with ≥90 days of monitoring were identified. Twelve strokes were adjudicated as CE and 19 as non-CE by a stroke neurologist. Six of the 12 CE stroke patients (50%) experienced AT/AF within 30 days preceding their stroke, while none of the 19 non-CE stroke patients recorded any AT/AF in the same period (p = 0.001). Four CE stroke patients (33%) had no AT/AF preceding their strokes at any time. The odds ratio for CE stroke was highest (39; 95% confidence interval [CI]: 1.92-791.5) when AT/AF occurred in the 30 days prior, declining to 20.65 (95% CI: 1.00-427.66) and 6.07 (95% CI: 0.94-39.04) in the subsequent 31-60- and 61-90-day windows, respectively. CONCLUSIONS: CE strokes were associated with a significantly higher proportion of preceding AT/AF compared with non-CE strokes. These findings support a potential temporal relationship between AT/AF and CE stroke and demonstrate that stroke subtyping can better characterize the relationship between AF and ischemic stroke. However, this study's findings are limited by its sample size and small number of informative cases.

Relationship between QT interval prolongation and structural abnormalities in cirrhotic cardiomyopathy: A change in the current paradigm.

It is postulated that cardiac structural abnormalities observed in cirrhotic cardiomyopathy (CCM) contribute to the electrophysiologic abnormality of QT interval (QTc) prolongation. We sought to evaluate whether QTc prolongation is associated with intrinsic abnormalities in cardiac structure and function that characterize CCM. Consecutive patients undergoing liver transplant work-up between 2010 and 2018 were included. Measures of cardiac function on stress testing including cardiac reserve and chronotropic incompetence were collected prospectively and a corrected QTc ≥ 440 ms was considered prolonged. Overall, 439 patients were included and 65.1% had a prolonged QTc. There were no differences in markers of left ventricular and atrial remodeling, or resting systolic and diastolic function across QTc groups. The proportion of patients that met the criteria for a low cardiac reserve (39.2 vs 36.6%, p = .66) or chronotropic incompetence (18.1 vs 21.3%, p = .52) was not different in those with a QTc ≥ 440 vs <440 ms. Further, there was no association between QTc prolongation and CCM by either the 2005 World College of Gastroenterology or modified 2020 Cirrhotic Cardiomyopathy Consortium criteria. QT interval prolongation was not associated with structural or functional cardiac abnormalities that characterize CCM. These findings suggest that CCM and QT interval prolongation in cirrhosis may be two separate entities with distinct pathophysiological origins.