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Ventricular ectopics can potentially lead to ventricular fibrillation (VF). A case of idiopathic VF that began as ventricular bigeminy is presented. A 30-year-old man lost consciousness transiently while driving but made a complete recovery soon after. He was pale and sweaty at the onset of the event. There was neither a history of ill health nor a family history of sudden cardiac death. He was asymptomatic on arrival at the emergency department (ED) with sinus tachycardia. Two hours later ventricular bigeminy was observed. This subtle presentation did not qualify him for being high risk according to the American College of Physician's recommendations or the San Francisco syncope rule, which almost led to his discharge from the ED. Despite this, he was admitted for observation. The patient had four VF arrests overnight, which were eventually terminated by emergency radiofrequency ablation. Upon further investigation, he was found to be normal on cardiac magnetic resonance imaging, echocardiogram and 24-h Holter monitoring. His serum biochemistry was normal, ruling out electrolyte disturbances. He eventually received an implantable cardioverter and remained free of recurrences in the subsequent months. This case serves as a reminder not to ignore ventricular ectopics or bigeminy. [ABSTRACT FROM AUTHOR]

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., (Copyright © 2024 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

Background: Indigenous Australians experience a greater burden of AF. Whether this is in-part due to differences in arrhythmogenic structures that appear to contribute to AF differences amongst other ethnicities is not known., Methods: We studied forty individuals matched for ethnicity and other AF risk factors. Computed tomography imaging was used to characterise left atrial (LA), pulmonary vein (PV), and left atrial appendage (LAA) anatomy., Results: There were no significant differences in LA diameters or volumes between Indigenous and non-Indigenous Australians. Similarly, we could not detect any consistent differences in PV number, morphology, diameters, or ostial characteristics according to ethnicity. LAA analyses suggested that Indigenous Australians may have a greater proportion of non chickenwing LAA type, and a tendency for eccentric, oval-shaped LAA ostia; however, there were no other differences seen with regards to LAA volume or depth. Indexed values for LA, PV and LAA anatomy corrected for body size were broadly similar., Conclusions: In a cohort of individuals matched for AF risk factors, we could find no strong evidence of ethnic differences in LA, PV, and LAA characteristics that may explain a predisposition of Indigenous Australians for atrial arrhythmogenesis. These findings, in conjunction with our previous data showing highly prevalent cardiometabolic risk factors in Indigenous Australians with AF, suggest that it is these conditions that are more likely responsible for the AF substrate in these individuals. Continued efforts should therefore be directed towards risk factor management in an attempt to prevent and minimise the effects of AF in Indigenous Australians., (© 2021 The Author(s).)

Background: Catheter-tissue contact force is an important factor influencing lesion size and efficacy and thereby potential for arrhythmia recurrence following accessory pathway (AP) radiofrequency ablation. We aim to evaluate adequacy and perception of catheter contact on the tricuspid and mitral annuli., Methods: Data were collected from 42 patients undergoing catheter ablation. Operators were blinded to contact force information and reported perceived contact (poor, moderate, or good) while positioning the catheter at four tricuspid annular sites (12, 9, 6 and 4 o'clock positions; abbreviated as TA12, TA9, TA6 and TA4) and three mitral annular sites (3, 5 and 7 o'clock positions; abbreviated as MA3, MA5 and MA7) through long vascular sheaths., Results: The highest and lowest mean contact forces were obtained at MA7 (13.3 ± 1.7 g) and TA12 (3.6 g ± 1.3 g) respectively. Mean contact force on tricuspid annulus (6.1 g ± 0.9 g) was lower than mitral annulus (9.8 ± 0.9 g) locations (p = 0.0036), with greater proportion of sites with <10 g contact force (81.7% vs 60.4%; p = 0.0075). Perceived contact had no impact on measured mean contact force for both mitral and tricuspid annular positions (p = 0.959 and 0.671 respectively). There was correlation of both impedance and atrial electrogram amplitude with contact force, though insufficient to be clinically applicable., Conclusion: A high proportion of annular catheter applications have low contact force despite being performed with long vascular sheaths in the hands of experienced operators. In addition, there was no impact of operator perceived contact force on actual measured contact force. This may carry implications for success of AP ablation., (Copyright © 2019 Indian Heart Rhythm Society. Production and hosting by Elsevier B.V. All rights reserved.)

Aims: This study aimed to assess prescribers' monitoring for arrhythmic risk with QT-prolonging medications (LQT drugs)., Methods: Over a 6-month period, all inpatients under the care of Cardiologists (Cohort A) and General Physicians (Cohort B) at Aberdeen Royal Infirmary who were prescribed drugs with known risk of Torsades de Pointes (TdP) were identified. Admission and repeat electrocardiograms (ECG) after 48 h of commencing a LQT drug were examined. Actions taken if QTc was prolonged and drug-drug interactions were examined. A risk estimate on the UK hospital population was calculated., Results: Of the 4133 patients admitted during the study period, 234 (6%) patients were prescribed a LQT drug. There were 100 (43%) patients in Cohort A and 134 (57%) patients in Cohort B. Of those admitted with a pre-existing LQT drug prescription, an ECG was performed in 167 (96%) of patients and QTc prolongation was identified in 59 (34%). Of those who received a new prescription of LQT drug, 23 (38%) had QTc prolongation and more patients in Cohort A than Cohort B had a repeat ECG within 48 h (84% vs. 11%, P < 0.0001). QTc prolongation was only recognized in 6 (14%) and 2 (5%) patients in cohorts A and B, respectively. Only one patient at risk of drug interaction had QTc prolongation. None of our patients had documented TdP in hospital. Extrapolating these findings to the UK hospital population, at least 204 and <17-175 patients on cardiac and noncardiac LQT drugs, respectively, might be expected to have TdP each year., Conclusion: Recognition of acquired QTc prolongation is poor. Clinician education and an electronic prescribing system may improve this situation., (© 2014 John Wiley & Sons Ltd.)

Introduction: This study aimed to examine whether general practitioner (GP) practice locations in remote and rural areas affected the pattern of direct access echocardiography referral and to assess any variations in echocardiographic findings., Methods: All referrals made by all GP practices in the Scottish Highlands over a 36-month period were analysed. Referral patterns were examined according to distance and rurality based on the Scottish Government's Urban-Rural Classification. Reasons for referral and cardiac abnormality detection rates were also examined., Results: In total, 1188 referrals were made from 49 different GP practices; range of referral rates was 0.3-20.1 per 1000 population with a mean of 6.5 referrals per 1000 population. Referral rates were not significantly different between urban and rural practices after correction for population size. There was no correlation between the referral rates and the distance from the centre (r2=0.004, p=0.65). The most common reason for referral was the presence of new murmur (46%). The most common presenting symptom was breathlessness (44%). Overall, 28% of studies had significant abnormal findings requiring direct input from a cardiologist. There was no clear relationship between referral rates and cardiac abnormality detection rates (r2=0.07, p=0.37). The average cardiac abnormality detection rate was 56%, (range 52-60%), with no variation based on rurality (p=0.891)., Conclusions: In this cohort, rurality and distance were not barriers to an equitable direct access echocardiography service. Cardiac abnormality detection rates are consistent with that of other studies.

We present a case of cardiac sarcoidosis of insidious onset mimicking arrhythmogenic right ventricular cardiomyopathy. Our patient initially presented with systemic sarcoidosis but later developed palpitations. The similarity in clinical presentation and cardiac magnetic resonance findings in both conditions posed a challenge in differentiating between the two in the absence of histological diagnosis. We highlighted the role of positron emission tomography in aiding a diagnosis.

Aims: The National Institute for Health and Clinical Excellence (NICE) recommends the use of dual-chamber pacemakers for all patients with bradycardia with a few exceptions. We aimed to evaluate our compliance to the guidelines and the implications of different pacing modalities on follow-up outcomes., Methods: We conducted two retrospective studies involving a total of 316 patients. The first study conducted over a 36-month period examined our performance prior to the introduction of the NICE guidance. The more recent second study conducted over a 12-month period examined our compliance to the NICE guidance upon its introduction and adoption. Data were analysed in separate groups according to pacemaker types. Symptom control and mortality were measures on follow-up outcomes., Results: Our compliance to the guidance increased from 72% in the former study to 78% in the latter study (P = 0.17). Symptom control and mortality were not significantly different between the two studies. Combining both studies, fewer NICE-compliant patients complained of persisting symptoms after 1 year (P = 0.36). Although fewer deaths were observed in the compliant group, this again was not statistically significant (P = 0.10). Although age was not a criteria in selecting a device, younger patients were more likely to receive a pacemaker according to NICE recommendations (P = 0.001)., Conclusions: We achieved a near 80% level of compliance to NICE guidance. Our non-NICE-compliant patients did not have a poorer outcome than those who were compliant. The decision to insert single- or dual-chamber pacemakers is often multifactorial and individual doctors may have different practices., (© 2011 Blackwell Publishing Ltd.)

BACKGROUND: Colonic polypectomy reduces the subsequent rate of development of colonic cancer but is not without its risks. We aimed to examine our complication rates in relation to the characteristics of polyps and techniques employed. METHODS: A database for all colonic polypectomies performed over a 3½-year period between 2006 and 2009 was matched against all patients readmitted after an endoscopy. Serious complications post-polypectomy were defined as events leading to readmission within 14 days. RESULTS: We performed 2106 polypectomies on 1252 patients in this period. Fourteen patients or 24 (1.1%) polypectomies experienced complications. Two patients (0.09%) experienced perforation, 10 (0.47%) had bleeding and 3 (0.14%) had post-polypectomy syndromes. Our bleeding rate was 1:211, lower than the national standard of 1:100. No deaths were reported. Complication rates rose from 1% in the smallest group (1-10 mm) to 4.9% in the largest (>31 mm) but the difference was not statistically significant (p=0.067). Right-colon polypectomies had a higher tendency of developing post-polypectomy syndrome and bleeding (p=0.002). Complication rates in snare polypectomies were not significantly different from that of hot biopsies (p=0.64). However, endoscopic mucosal resections (EMR) had significantly more complications compared to snares (p=0.045) and hot biopsies (p=0.026). CONCLUSION: We achieved lower bleeding rates than that published nationally. Hot biopsies did not carry a higher risk unlike EMRs. Although polyp size may be an important risk factor, statistical significance was not met. Ascending and transverse colon polypectomies carried the highest risks of complications.

Background: Catheter ablation is widely used to treat symptomatic atrial fibrillation (AF) refractory to drug therapy; and can be facilitated by a number of different techniques., Aims: To evaluate our performance as a new centre for AF ablation and to evaluate the efficacy of different AF ablation techniques., Methods: We employed three techniques in AF ablations; the three-dimensional (3D) mapping approaches (CARTO or Ensite NavX) or multielectrode catheter duty-cycled radiofrequency ablation (pulmonary vein ablation catheter [PVAC]). The immediate restoration of sinus rhythm was considered as acute success; while success at 6 months was determined by the maintenance of sinus rhythm on Holter monitoring., Results: Between March 2008 and March 2010, 109 patients underwent AF ablations (mean age: 58 years; 72% male). Six-month success rates did not differ significantly between CARTO and NavX (40% vs 38%; P=0.81), but the PVAC group achieved greater success than the two 3D-mapping groups combined (68% vs 39%; P=0.004). Paroxysmal AF patients demonstrated greater 6-month success than persistent AF patients (P=0.005); and although the ratio of paroxysmal to persistent AF patients was slightly higher among the PVAC group, logistic regression confirmed PVAC and paroxysmal AF as predictors of success. Single-procedure success at 6 months was 48%. Including redo-ablations, some performed beyond the study period, our overall success rate at 6 months was 65%. Four patients experienced complications, but there were no deaths., Conclusion: Despite being a new centre with relative inexperience, we achieved success rates comparable to those of established tertiary centres. PVAC performed significantly better than the two 3D-mapping approaches., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Introduction: Menstruation is commonly associated with migraine and irritable bowel but is rarely correlated with angina or myocardial ischaemia. Only a small number of cases have been reported suggesting a link between menstruation and myocardial ischaemic events., Case Presentation: A case of menstruation angina is reported in order to raise awareness of this association. A 47-year-old South Asian woman presented with recurrent chest pains in a monthly fashion coinciding with her menstruations. Each presentation was associated with troponin elevation. Angioplasty failed to resolve her symptoms but she eventually responded to hormonal therapy., Conclusions: The possibility of menstruation angina should always be taken into account in any female patients from puberty to menopause presenting with recurrent chest pains. This can allow an earlier introduction of hormonal therapy to arrest further myocardial damage.

The room-temperature structure of the B-site-ordered complex perovskite dicalcium magnesium tungstate, Ca(2)MgWO(6), has been determined by simultaneous Rietveld refinement of neutron and X-ray powder diffraction patterns. Ca(2)MgWO(6) is characterized by B-site ordering and an a(-)a(-)c(+)-type BO(6) octahedral tilt mechanism.

The room-temperature crystal structure of the B-site ordered complex perovskite strontium ytterbium niobate, Sr(Yb(0.5)Nb(0.5))O(3) [monoclinic, Z = 2, P2(1)/n (set 2), a = 5.79095 (8), b = 5.82210 (7), c = 8.20358 (12) Å, beta = 90.126 (1) degrees, with final R(wp) = 0.0595, R(Bragg) = 0.0203 for the neutron profile and R(wp) = 0.0832, R(Bragg) = 0.0193 for the X-ray profile, respectively], was determined by X-ray powder diffraction, high-resolution neutron powder diffraction and transmission electron microscopy. This compound shows a slight triclinic distortion from the prototype doubled cubic perovskite cell as a result of an a(-)a(-)c(+)-type oxygen octahedral tilting distortion. It is also shown that the site ordering of the different species of B-site cations, Yb(3+) and Nb(5+), inherently leads to a difference between the volumes of the YbO(6) and NbO(6) octahedra. This volume difference is shown to inevitably inhibit the rigid rotation of octahedra.

The types of Kunjin virus-specified proteins present in purified Vero cell plasma membrane were studied. Immunofluorescence of unfixed Kunjin virus-infected whole cell monolayers, indicated that two structural proteins (envelope and prM) and three non-structural proteins (NS1, 3 and 5) were found at the plasma membrane. There was no obvious progressive accumulation of the observed antigens over the time periods between 8 to 24 h p.i. Thus SDS-PAGE analysis was performed using purified radiolabelled Vero cell plasma membranes. From the protein profiles, all five antigens detected by immunofluorescent staining were also present. In addition, two smaller molecular weight non-structural proteins NS4B and NS2B were also observed. Generally, all the non-structural proteins found in the purified plasma membranes were of the same molecular weights as those found in infected whole cell lysate. Interestingly, both the structural proteins, i.e., envelope (E) and prM proteins in the plasma membrane sample were of higher molecular weights as compared to the counterparts in the infected whole cell lysate. The envelope protein of purified extracellular Kunjin virus was also lower in molecular weight compared to the same protein in the plasma membrane.