[Control of arterial hypertension: a pending issueControle da hipertensão arterial: um assunto inacabado]. / El control de la hipertensión arterial, una asignatura pendiente.

Adequate diagnosis, treatment, and control of arterial hypertension (AHT) continues to be a pending issue in the attempt to reduce the incidence of premature mortality and disability due to cardiovascular disease, which is a reality worldwide and in the region of the Americas in particular.Despite having adequate diagnostic algorithms and efficient treatment schemes, the gap between medical knowledge and reality reveals the great difficulty in ensuring that patients follow recommendations. Adherence to treatment is a great challenge and a proper understanding of its dimensions is essential when designing strategies to improve control of AHT.It is clear that part of the solution is having adequate information and disseminating it, but actions that guarantee implementation are no less important. That is why clinical practice guidelines that try to address this problem are welcome. The recent publication of the World Health Organization's guidance on arterial hypertension is a clear example of this type of initiative.Implementation programs are arguably one of the biggest challenges in contemporary medicine. The development of multimodal interventions aimed at improving response capacity at the first level of care and promoting the development of integrated health services networks appears to be the most appropriate way to achieve adequate control of AHT.Scientific societies clearly play an important role in these initiatives by providing support and coordinating interactions among the different actors involved.

O diagnóstico, tratamento e controle adequados da hipertensão arterial sistêmica (HAS) continua sendo uma questão pendente em nossa tentativa de reduzir a incidência de mortalidade cardiovascular prematura e a incapacidade. Essa é a realidade no nível mundial e, particularmente, na região das Américas.Apesar de algoritmos de diagnóstico adequados e esquemas de tratamento eficientes, a lacuna entre o conhecimento médico e a realidade nos mostra como é difícil que nossas recomendações sejam adotadas por nossos pacientes. A adesão representa um grande desafio, e uma compreensão adequada de suas dimensões é essencial ao se projetar estratégias para melhorar o controle da HAS.Claramente, a disponibilidade e a divulgação de informações adequadas é parte da solução, mas não menos importantes são as ações para garantir sua implementação. Portanto, acolhemos de bom grado as diretrizes de prática clínica que visam abordar esta questão. A recente publicação das diretrizes da Organização Mundial da Saúde sobre hipertensão arterial é um claro exemplo de tais iniciativas.Os programas de implementação são indiscutivelmente um dos maiores desafios da medicina contemporânea. O desenvolvimento de intervenções multimodais na atenção primária com o objetivo de melhorar sua resolutividade e promover o desenvolvimento de redes integradas de serviços de saúde parece ser a forma mais apropriada para atingir níveis adequados de controle da HAS.Estamos convencidos do importante papel que nossas sociedades científicas desempenham nestas iniciativas ao prestar apoio, suporte e articulação aos diferentes atores envolvidos.

El control de la hipertensión arterial, una asignatura pendiente

[RESUMEN]. El adecuado diagnóstico, tratamiento y control de la hipertensión arterial (HTA) continúa siendo una asignatura pendiente en nuestro intento de reducir la incidencia de mortalidad cardiovascular prematura y discapacidades, siendo esta una realidad a nivel mundial y particularmente cierta en la región de las Américas. A pesar de contar con adecuados algoritmos diagnósticos y eficientes esquemas de tratamiento, la brecha entre el conocimiento médico y la realidad nos muestra la gran dificultad para que nuestras recomendaciones sean adoptadas por nuestros pacientes. La adherencia representa un gran desafío y la adecuada comprensión de sus dimensiones resulta básico al momento de diseñar estrategias para mejorar el control de la HTA. Es claro que disponer y diseminar información adecuada es una parte de la solución, pero no menos importante son las acciones que garanticen su implementación. Es por lo que damos la bienvenida a guías de práctica clínica que intenten abordar esta problemática. La reciente publicación de guía de la Organización Mundial de la Salud en hipertensión arterial es un claro ejemplo de este tipo de iniciativas. Los programas de implementación posiblemente sean uno de los mayores desafíos de la medicina contemporánea. El desarrollo de intervenciones multimodales en el primer nivel de atención con el objetivo de mejorar su capacidad resolutiva y promover el desarrollo de redes integradas de servicios de salud, impresiona ser el camino mas adecuado para alcanzar niveles adecuados de control de la HTA. Estamos convencidos del importante rol que nuestras sociedades científicas tienen con estas iniciativas dando apoyo, soporte y articulando la interacción con los diferentes actores involucrados.

[ABSTRACT]. Adequate diagnosis, treatment, and control of arterial hypertension (AHT) continues to be a pending issue in the attempt to reduce the incidence of premature mortality and disability due to cardiovascular disease, which is a reality worldwide and in the region of the Americas in particular. Despite having adequate diagnostic algorithms and efficient treatment schemes, the gap between medical knowledge and reality reveals the great difficulty in ensuring that patients follow recommendations. Adherence to treatment is a great challenge and a proper understanding of its dimensions is essential when designing strategies to improve control of AHT. It is clear that part of the solution is having adequate information and disseminating it, but actions that guarantee implementation are no less important. That is why clinical practice guidelines that try to address this problem are welcome. The recent publication of the World Health Organization's guidance on arterial hypertension is a clear example of this type of initiative. Implementation programs are arguably one of the biggest challenges in contemporary medicine. The development of multimodal interventions aimed at improving response capacity at the first level of care and promoting the development of integrated health services networks appears to be the most appropriate way to achieve adequate control of AHT. Scientific societies clearly play an important role in these initiatives by providing support and coordinating interactions among the different actors involved.

[RESUMO]. O diagnóstico, tratamento e controle adequados da hipertensão arterial sistêmica (HAS) continua sendo uma questão pendente em nossa tentativa de reduzir a incidência de mortalidade cardiovascular prematura e a incapacidade. Essa é a realidade no nível mundial e, particularmente, na região das Américas. Apesar de algoritmos de diagnóstico adequados e esquemas de tratamento eficientes, a lacuna entre o conhecimento médico e a realidade nos mostra como é difícil que nossas recomendações sejam adotadas por nossos pacientes. A adesão representa um grande desafio, e uma compreensão adequada de suas dimensões é essencial ao se projetar estratégias para melhorar o controle da HAS. Claramente, a disponibilidade e a divulgação de informações adequadas é parte da solução, mas não menos importantes são as ações para garantir sua implementação. Portanto, acolhemos de bom grado as diretrizes de prática clínica que visam abordar esta questão. A recente publicação das diretrizes da Organização Mundial da Saúde sobre hipertensão arterial é um claro exemplo de tais iniciativas. Os programas de implementação são indiscutivelmente um dos maiores desafios da medicina contemporânea. O desenvolvimento de intervenções multimodais na atenção primária com o objetivo de melhorar sua resolutividade e promover o desenvolvimento de redes integradas de serviços de saúde parece ser a forma mais apropriada para atingir níveis adequados de controle da HAS. Estamos convencidos do importante papel que nossas sociedades científicas desempenham nestas iniciativas ao prestar apoio, suporte e articulação aos diferentes atores envolvidos.

El control de la hipertensión arterial, una asignatura pendiente / Control of arterial hypertension: a pending issue / Controle da hipertensão arterial: um assunto inacabado

RESUMEN El adecuado diagnóstico, tratamiento y control de la hipertensión arterial (HTA) continúa siendo una asignatura pendiente en nuestro intento de reducir la incidencia de mortalidad cardiovascular prematura y discapacidades, siendo esta una realidad a nivel mundial y particularmente cierta en la región de las Américas. A pesar de contar con adecuados algoritmos diagnósticos y eficientes esquemas de tratamiento, la brecha entre el conocimiento médico y la realidad nos muestra la gran dificultad para que nuestras recomendaciones sean adoptadas por nuestros pacientes. La adherencia representa un gran desafío y la adecuada comprensión de sus dimensiones resulta básico al momento de diseñar estrategias para mejorar el control de la HTA. Es claro que disponer y diseminar información adecuada es una parte de la solución, pero no menos importante son las acciones que garanticen su implementación. Es por lo que damos la bienvenida a guías de práctica clínica que intenten abordar esta problemática. La reciente publicación de guía de la Organización Mundial de la Salud en hipertensión arterial es un claro ejemplo de este tipo de iniciativas. Los programas de implementación posiblemente sean uno de los mayores desafíos de la medicina contemporánea. El desarrollo de intervenciones multimodales en el primer nivel de atención con el objetivo de mejorar su capacidad resolutiva y promover el desarrollo de redes integradas de servicios de salud, impresiona ser el camino mas adecuado para alcanzar niveles adecuados de control de la HTA. Estamos convencidos del importante rol que nuestras sociedades científicas tienen con estas iniciativas dando apoyo, soporte y articulando la interacción con los diferentes actores involucrados.

ABSTRACT Adequate diagnosis, treatment, and control of arterial hypertension (AHT) continues to be a pending issue in the attempt to reduce the incidence of premature mortality and disability due to cardiovascular disease, which is a reality worldwide and in the region of the Americas in particular. Despite having adequate diagnostic algorithms and efficient treatment schemes, the gap between medical knowledge and reality reveals the great difficulty in ensuring that patients follow recommendations. Adherence to treatment is a great challenge and a proper understanding of its dimensions is essential when designing strategies to improve control of AHT. It is clear that part of the solution is having adequate information and disseminating it, but actions that guarantee implementation are no less important. That is why clinical practice guidelines that try to address this problem are welcome. The recent publication of the World Health Organization's guidance on arterial hypertension is a clear example of this type of initiative. Implementation programs are arguably one of the biggest challenges in contemporary medicine. The development of multimodal interventions aimed at improving response capacity at the first level of care and promoting the development of integrated health services networks appears to be the most appropriate way to achieve adequate control of AHT. Scientific societies clearly play an important role in these initiatives by providing support and coordinating interactions among the different actors involved.

RESUMO O diagnóstico, tratamento e controle adequados da hipertensão arterial sistêmica (HAS) continua sendo uma questão pendente em nossa tentativa de reduzir a incidência de mortalidade cardiovascular prematura e a incapacidade. Essa é a realidade no nível mundial e, particularmente, na região das Américas. Apesar de algoritmos de diagnóstico adequados e esquemas de tratamento eficientes, a lacuna entre o conhecimento médico e a realidade nos mostra como é difícil que nossas recomendações sejam adotadas por nossos pacientes. A adesão representa um grande desafio, e uma compreensão adequada de suas dimensões é essencial ao se projetar estratégias para melhorar o controle da HAS. Claramente, a disponibilidade e a divulgação de informações adequadas é parte da solução, mas não menos importantes são as ações para garantir sua implementação. Portanto, acolhemos de bom grado as diretrizes de prática clínica que visam abordar esta questão. A recente publicação das diretrizes da Organização Mundial da Saúde sobre hipertensão arterial é um claro exemplo de tais iniciativas. Os programas de implementação são indiscutivelmente um dos maiores desafios da medicina contemporânea. O desenvolvimento de intervenções multimodais na atenção primária com o objetivo de melhorar sua resolutividade e promover o desenvolvimento de redes integradas de serviços de saúde parece ser a forma mais apropriada para atingir níveis adequados de controle da HAS. Estamos convencidos do importante papel que nossas sociedades científicas desempenham nestas iniciativas ao prestar apoio, suporte e articulação aos diferentes atores envolvidos.

World Heart Federation Roadmap on Atrial Fibrillation - A 2020 Update.

The World Heart Federation (WHF) commenced a Roadmap initiative in 2015 to reduce the global burden of cardiovascular disease and resultant burgeoning of healthcare costs. Roadmaps provide a blueprint for implementation of priority solutions for the principal cardiovascular diseases leading to death and disability. Atrial fibrillation (AF) is one of these conditions and is an increasing problem due to ageing of the world's population and an increase in cardiovascular risk factors that predispose to AF. The goal of the AF roadmap was to provide guidance on priority interventions that are feasible in multiple countries, and to identify roadblocks and potential strategies to overcome them. Since publication of the AF Roadmap in 2017, there have been many technological advances including devices and artificial intelligence for identification and prediction of unknown AF, better methods to achieve rhythm control, and widespread uptake of smartphones and apps that could facilitate new approaches to healthcare delivery and increasing community AF awareness. In addition, the World Health Organisation added the non-vitamin K antagonist oral anticoagulants (NOACs) to the Essential Medicines List, making it possible to increase advocacy for their widespread adoption as therapy to prevent stroke. These advances motivated the WHF to commission a 2020 AF Roadmap update. Three years after the original Roadmap publication, the identified barriers and solutions were judged still relevant, and progress has been slow. This 2020 Roadmap update reviews the significant changes since 2017 and identifies priority areas for achieving the goals of reducing death and disability related to AF, particularly targeted at low-middle income countries. These include advocacy to increase appreciation of the scope of the problem; plugging gaps in guideline management and prevention through physician education, increasing patient health literacy, and novel ways to increase access to integrated healthcare including mHealth and digital transformations; and greater emphasis on achieving practical solutions to national and regional entrenched barriers. Despite the advances reviewed in this update, the task will not be easy, but the health rewards of implementing solutions that are both innovative and practical will be great.

The use of minimal fluoroscopy for cardiac electrophysiology procedures: A meta-analysis and review of the literature.

BACKGROUND: Conventional catheter ablation involves prolonged exposure to ionizing radiation, potentially leading to detrimental health effects. Minimal fluoroscopy (MF) represents a safer alternative, which should be explored. Data on the safety and efficacy of this technique are limited. HYPOTHESIS: Our hypothesis is that MF is of equal efficacy and safety to conventional catheter ablation with the use of fluoroscopy by performing a meta-analysis of both randomized controlled trials (RCTs) and real-world registry studies. METHODS: Pubmed and Embase were searched from their inception to July 2020 for RCTs, cohort and observational studies that assessed the outcomes of catheter ablation using a MF technique versus the conventional approach. RESULTS: Fifteen studies involving 3795 patients were included in this meta-analysis. There was a significant reduction in fluoroscopy and procedural time with no difference in acute success (odds ratio [OR]:0.74, 95% CI: 0.50-1.10, p = .14), long-term success (OR:0.92, 95% CI: 0.65-1.31, p = .38), arrhythmia recurrence (OR:1.24, 95% CI: 0.75-2.06, p = .97) or rate of complications. (OR:0.83, 95% CI: 0.46-1.48, p = .65). Additionally sub-group analysis for those undergoing catheter ablation for atrial fibrillation (AF) did not demonstrate a difference in success or complication rates (OR:0.86, 95% CI: 0.30-2.42, p = .77). Multivariate meta-regression did not identify the presence of moderator variables. CONCLUSION: This updated meta-analysis demonstrated an overall reduction in procedural and fluoroscopy time for those undergoing a minimal fluoroscopic approach. There was no significant difference in either acute or chronic success rates or complications between a MF approach and conventional approach for the management of all arrhythmias including those undergoing catheter ablation for AF.

Close-coupled pacing to identify the "functional" substrate of ventricular tachycardia: Long-term outcomes of the paced electrogram feature analysis technique.

BACKGROUND: The conduction delay and block that compose the critical isthmus of macroreentrant ventricular tachycardia (VT) is partly "functional" in that they only occur at faster cycle lengths. Close-coupled pacing stresses the myocardium's conduction capacity and may reveal late potentials (LPs) and fractionation. Interest has emerged in targeting this functional substrate. OBJECTIVE: The purpose of this study was to assess the feasibility and efficacy of a functional substrate VT ablation strategy. METHODS: Patients with scar-related VT undergoing their first ablation were recruited. A closely coupled extrastimulus (ventricular effective refractory period + 30 ms) was delivered at the right ventricular apex while mapping with a high-density catheter. Sites of functional impaired conduction exhibited increased electrogram duration due to LPs/fractionation. The time to last deflection was annotated on an electroanatomic map, readily identifying ablation targets. RESULTS: A total of 40 patients were recruited (34 [85%] ischemic). Median procedure duration was 330 minutes (interquartile range [IQR] 300-369), and ablation time was 49.4 minutes (IQR 33.8-48.3). Median functional substrate area was 41.9 cm2 (IQR 22.1-73.9). It was similarly distributed across bipolar voltage zones. Noninducibility was achieved in 34 of 40 patients (85%). Median follow-up was 711 days (IQR 255.5-972.8), during which 35 of 39 patients (89.7%) did not have VT recurrence, and 3 of 39 (7.5%) died. Antiarrhythmic drugs were continued in 53.8% (21/39). CONCLUSION: Functional substrate ablation resulted in high rates of noninducibility and freedom from VT. Mapping times were increased considerably. Our findings add to the encouraging trend reported by related techniques. Randomized multicenter trials are warranted to assess this next phase of VT ablation.

Right ventricular outflow tract low-voltage areas identify the site of origin of idiopathic ventricular arrhythmias: A high-density mapping study.

INTRODUCTION: Electronatomical mapping allows direct and accurate visualization of myocardial abnormalities. This study investigated whether high-density endocardial bipolar voltage mapping of the right ventricular outflow tract (RVOT) during sinus rhythm may guide catheter ablation of idiopathic ventricular arrhythmias (VAs). METHODS AND RESULTS: Forty-four patients (18 males, mean age: 38.1 ± 13.8 years) with idiopathic RVOT VAs and negative cardiac magnetic resonance imaging underwent a stepwise mapping approach for the identification of the site of origin (SOO). High-density electronatomical mapping (1096.6 ± 322.3 points) was performed during sinus rhythm and identified at least two low bipolar voltage areas less than 1 mV (mean amplitude of 0.20 ± 0.10 mV) in 39 of 44 patients. The mean low-voltage surface area was 1.4 ± 0.8 cm2 . Group 1 consisted of 28 patients exhibiting low-voltage areas and high-arrhythmia burden during the procedure. Pace match to the clinical VAs was produced in one of these low-voltage areas. Activation mapping established the SOO at these sites in 27 of 28 cases. Group 2 comprised 11 patients exhibiting abnormal electroanatomical mapping, but very low-arrhythmia burden during the procedure. Pace mapping produced a near-perfect or perfect match to the clinical VAs in one of these areas in 9 of 11 patients which was marked as potential SOO and targeted for ablation. During the follow-up period, 25 of 28 patients from group 1 (89%) and 7 of 9 patients from group 2 (78%) were free from VAs. CONCLUSIONS: Small but detectable very low-voltage areas during mapping in sinus rhythm characterize the arrhythmogenic substrate of idiopathic RVOT VAs and may guide successful catheter ablation.

[Management of bleeding associated with direct oral anticoagulants: update on reversal strategies]. / Manejo de hemorragia asociada a anticoagulantes orales directos: estado actual de las estrategias de reversión.

Direct oral anticoagulants (DOACs), including the direct thrombin inhibitor dabigatran and the direct factor Xa inhibitors rivaroxaban, apixaban and edoxaban have at least comparable efficacy as vitamin K antagonists along with a better safety profile, reflected by a lower incidence of intracranial hemorrhage. Specific reversal agents have been developed in recent years. Namely, idarucizumab, a specific antidote for dabigatran, is currently approved in most countries. Andexanet, which reverses factor Xa inhibitors, has been recently approved by the FDA, and ciraparantag, a universal antidote targeted to reverse all DOACs, is still under investigation. In this review we provide an update on the pharmacology of DOACs, the risk of hemorrhagic complications associated with their use, the measurement of their anticoagulant effect and the reversal strategies in case of DOAC-associated bleeding.

Ventricular substrate identification using close-coupled paced electrogram feature analysis.

AIMS: Substrate based catheter ablation strategies are widely employed for treatment of scar-related ventricular tachycardia (VT). We analysed intracardiac electrograms (EGMs) from close-coupled paced extrastimuli extracted from the EnSite Precision mapping system. We sought to characterize EGM responses of ventricular myocardium to varying coupling intervals from the right ventricular apex (RVA) in both healthy individuals and patients presenting with VT for catheter ablation. METHODS AND RESULTS: Extrastimuli were delivered from the RVA after estimation of the ventricular effective refractory period. Electrograms were recorded from high-density mapping catheters in the left ventricle and exported for analysis to MATLAB. Observational data were collected from 14 patients with ischaemic VT (mean age 72.4 ± 6.3 years, one female) and five controls (mean age 59.4 ± 7.4 years, one female). These derived data were used to inform an interventional strategy on a further 10 patients (mean age 64.7 ± 10.0 years; two female). Significant differences were observed in EGM duration (ED) and latency (LT) at all coupling intervals between VT patients and controls. Significant increases in ED and LT with decreased RVA coupling interval were observed at VT isthmuses. Abnormal responses derived from control subject data were used to classify four types of ventricular EGM response. Targeting sites with abnormal LT and ED significantly reduced VT inducibility (5/14 derivation patients to 0/10 intervention patients; P = 0.03). CONCLUSION: Paced electrogram feature analysis is a novel tool to characterize the ischaemic substrate. Association with VT isthmuses and early ablation results suggest a possible role in substrate ablation for ischaemic VT.

Cardiac resynchronization therapy-induced acute shortening of QRS duration predicts long-term mortality only in patients with left bundle branch block.

AIMS: QRS narrowing with initiation of biventricular pacing might be an acute electrocardiographic indicator of correction of left bundle branch block (LBBB)-induced depolarization delay and asynchrony. However, its impact on prognosis remains controversial, especially in non-LBBB patients. Our goal was to evaluate the impact of QRS narrowing on long-term mortality and morbidity in a large cohort of patients undergoing cardiac resynchronization therapy (CRT) with different pre-implantation QRS types: LBBB, non-LBBB, and permanent right ventricular pacing. METHODS AND RESULTS: This study included consecutive patients who underwent CRT device implantation. Study endpoints: death from any cause or urgent heart transplantation and death from any cause/urgent heart transplantation or hospital admission for heart failure. All pre- and post-implantation electrocardiograms were analysed using digital callipers, high-amplitude augmentation, 100 mm/s paper speed, and global QRS duration measurement method. A total of 552 CRT patients entered the survival analysis. During the 9 years observation period, 232 (42.0%) and 292 (52.9%) patients met primary and secondary endpoints, respectively. QRS narrowing predicted survival in the Kaplan-Meier analysis only in patients with LBBB. Multivariate Cox regression model showed that QRS narrowing was the major determinant of both study endpoints, with hazard ratios of 0.46 and 0.43, respectively. There was a strong relationship between mortality risk and shortening/widening of the QRS, albeit only in the LBBB group. Patients with non-LBBB morphologies had unfavourable prognosis similar to that in LBBB patients without QRS narrowing. CONCLUSION: Acute QRS narrowing in patients with LBBB might be a desirable endpoint of CRT device implantation.

Manejo de hemorragia asociada a anticoagulantes orales directos: estado actual de las estrategias de reversión / Management of bleeding associated with direct oral anticoagulants: update on reversal strategies

Direct oral anticoagulants (DOACs), including the direct thrombin inhibitor dabigatran and the direct factor Xa inhibitors rivaroxaban, apixaban and edoxaban have at least comparable efficacy as vitamin K antagonists along with a better safety profile, reflected by a lower incidence of intracranial hemorrhage. Specific reversal agents have been developed in recent years. Namely, idarucizumab, a specific antidote for dabigatran, is currently approved in most countries. Andexanet, which reverses factor Xa inhibitors, has been recently approved by the FDA, and ciraparantag, a universal antidote targeted to reverse all DOACs, is still under investigation. In this review we provide an update on the pharmacology of DOACs, the risk of hemorrhagic complications associated with their use, the measurement of their anticoagulant effect and the reversal strategies in case of DOAC-associated bleeding.

Rivaroxaban in the cardiovascular world: a direct anticoagulant useful to prevent stroke and venous and arterial thromboembolism.

INTRODUCTION: Until recently, vitamin K antagonists (VKA) were the only drugs available for long-term anticoagulation. The use of these drugs is laborious due to their variable pharmacokinetics and pharmacodynamics. The advent of direct oral anticoagulants has produced a paradigm shift due to their low incidence of drug interactions, their stable plasma levels, and their lack of monitoring. Rivaroxaban, a factor Xa inhibitor, has been tested in different clinical scenarios and has proved to be effective and safe, even increasing the scope of the old VKA. Areas covered: A non-systematic review of the literature was conducted using the PubMed and Cochrane databases, focusing on randomized clinical trials and real-world observational studies that evaluated rivaroxaban in patients with atrial fibrillation, venous thromboembolism, and atherosclerotic coronary and peripheral vascular disease. Expert commentary: The role of rivaroxaban keeps expanding into areas that were unimaginable few years ago, in the light of solid evidence that has eliminated old strict paradigms. Nonetheless, it will be necessary to adjust costs and better understand the perceived barriers to its widespread implementation, to get fully acceptation of rivaroxaban for the different clinical conditions that have been suggested.

Cybersecurity for Cardiac Implantable Electronic Devices: What Should You Know?

Medical devices have been targets of hacking for over a decade, and this cybersecurity issue has affected many types of medical devices. Lately, the potential for hacking of cardiac devices (pacemakers and defibrillators) claimed the attention of the media, patients, and health care providers. This is a burgeoning problem that our newly electronically connected world faces. In this paper from the Electrophysiology Section Council, we briefly discuss various aspects of this relatively new threat in light of recent incidents involving the potential for hacking of cardiac devices. We explore the possible risks for the patients and the effect of device reconfiguration in an attempt to thwart cybersecurity threats. We provide an outline of what can be done to improve cybersecurity from the standpoint of the manufacturer, government, professional societies, physician, and patient.

Intermittent preexcitation indicates "a low-risk" accessory pathway: Time for a paradigm shift?

We report three patients with intermittent loss of the preexcitation pattern in the ECG that had undergone an electrophysiological study. Despite apparently poorly conducting accessory pathway (AP), in each case a fast anterograde conduction, either during spontaneous atrial fibrillation or during incremental atrial pacing (on isoproterenol) was documented; shortest preexcited RR intervals of 200-240 ms were observed. We review the literature and conclude that intermittent preexcitation observed on resting 12-lead ECG lacks sufficient specificity for the diagnosis of an AP with long refractory period and cannot be considered a substitute for electrophysiological study in patients with this electrocardiographical phenomenon.

Resident Physicians Choices of Anticoagulation for Stroke Prevention in Patients With Nonvalvular Atrial Fibrillation.

Atrial fibrillation (AF) is a common cardiac arrhythmia and is associated with an increased risk of ischemic stroke. The aim of this study was to identify practice patterns of Canadian resident physicians pertaining to stroke prevention in nonvalvular AF according to the Canadian Cardiovascular Society guidelines. A Web-based survey consisting of 16 multiple-choice questions was distributed to 11 academic centres. Questions involved identification of risks of stroke, bleeding, and selection of appropriate therapy in clinical scenarios that involve a patient with AF with a Congestive Heart Failure, Hypertension, Age, Diabetes, Stroke/Transient Ischemic Attack (CHADS2) score of 3 and no absolute contraindications to anticoagulation. There were 1014 total respondents, of whom 570 were internal, 247 family, 137 emergency medicine, and 60 adult cardiology residents. For a patient with a new diagnosis of AF, warfarin was chosen by 80.3%, novel oral anticoagulants (NOACs) by 60.3%, and acetylsalicylic acid (ASA) by 7.2% of residents. To a patient with a history of gastrointestinal bleed during ASA treatment, warfarin was recommended by 75.1%, NOACs by 36.1%, ASA by 12.1%, and 4% were unsure. For a patient with a history of an intracranial bleed, warfarin was recommended by 38.8%, NOACs by 23%, ASA by 24.8%, and 18.2% were unsure. For a patient taking warfarin who had a labile international normalized ratio, 89% would switch to a NOAC and 29.5% would continue warfarin. This study revealed that, across a wide sampling of disciplines and centres, resident physician choices of anticoagulation in nonvalvular AF differ significantly from contemporary Canadian Cardiovascular Society guidelines.

Unipolar voltage threshold of 5.0 mV is optimal to localize critical isthmuses in post-infarction patients presenting with ventricular tachycardia.

INTRODUCTION: Bipolar voltage mapping is useful to delineate post-infarct endocardial scar and guide ablation of ischemic VT. The role of unipolar mapping is not yet well defined. The aim of this study was to assess the correlation between electrophysiological findings in patients with ischemic VT and unipolar voltage maps using different cut-offs. METHODS: We included 10 patients (age 67 ± 7 years, ejection fraction 33 ± 10%) with ischemic cardiomyopathy undergoing catheter ablation for recurrent VT. Patients with right-sided VTs were excluded. In all patients a unipolar voltage map was constructed during right ventricular pacing. Ablation was performed guided by activation and entrainment mapping in hemodynamically stable VTs and by pace-mapping and abnormal (late/split/fractionated) potentials in unstable VTs. Subsequently, the unipolar voltage maps were analyzed off-line using cutoffs from 1.0 to 8.0 mV and correlated with the isthmus sites. RESULTS: A total of 17 sustained VTs were induced in the 10 patients and non-inducibility of the clinical VT was achieved in 90% of patients by endocardial ablation. The optimal cutoff was 5.0 mV. By using this value, the mean surface area of abnormal unipolar voltage was 43.8% and 95% of all VT isthmuses were located within the area of scar, as well as 81% of abnormal potentials. In addition, 71% of isthmuses were at less than 1cm from the scar border. CONCLUSION: Unipolar voltage mapping showed good correlation with areas of isthmuses and abnormal electrograms in patients with scar-related VT, with a cut-off of 5.0 mV allowing the best delineation of ablation targets.

Electrophysiology study without intracardiac catheters. The value of proper Holter interpretation: a case report.

This case report presents the case of a 55-year-old male patient with a long-standing history of palpitations. A 24-h Holter monitor revealed an incessant form of long-RP supraventricular tachycardia. The differential diagnosis is presented and discussed. In a stepwise approach, it is explained how the exact mechanism of the tachycardia can be inferred through careful examination of the multiple onsets, terminations and response to spontaneous monomorphic premature ventricular contractions.