Brugada syndrome and reduced right ventricular outflow tract conduction reserve: a final common pathway?

Brugada syndrome (BrS) was first described as a primary electrical disorder predisposing to the risk of sudden cardiac death and characterized by right precordial lead ST elevation. Early description of right ventricular structural abnormalities and of right ventricular outflow tract (RVOT) conduction delay in BrS patients set the stage for the current controversy over the pathophysiology underlying the syndrome: channelopathy or cardiomyopathy; repolarization or depolarization. This review examines the current understanding of the BrS substrate, its genetic and non-genetic basis, theories of pathophysiology, and the clinical implications thereof. We propose that the final common pathway for BrS could be viewed as a disease of 'reduced RVOT conduction reserve'.

Guidance for Rebooting Electrophysiology Through the COVID-19 Pandemic From the Heart Rhythm Society and the American Heart Association Electrocardiography and Arrhythmias Committee of the Council on Clinical Cardiology: Endorsed by the American College of Cardiology.

Coronavirus disease 2019 (COVID-19) has presented substantial challenges to patient care and impacted health care delivery, including cardiac electrophysiology practice throughout the globe. Based upon the undetermined course and regional variability of the pandemic, there is uncertainty as to how and when to resume and deliver electrophysiology services for arrhythmia patients. This joint document from representatives of the Heart Rhythm Society, American Heart Association, and American College of Cardiology seeks to provide guidance for clinicians and institutions reestablishing safe electrophysiological care. To achieve this aim, we address regional and local COVID-19 disease status, the role of viral screening and serologic testing, return-to-work considerations for exposed or infected health care workers, risk stratification and management strategies based on COVID-19 disease burden, institutional preparedness for resumption of elective procedures, patient preparation and communication, prioritization of procedures, and development of outpatient and periprocedural care pathways.

Cardiovascular Care Delivery During the Second Wave of COVID-19 in Canada.

Hospitals and ambulatory facilities significantly reduced cardiac care delivery in response to the first wave of the COVID-19 pandemic. The deferral of elective cardiovascular procedures led to a marked reduction in health care delivery with a significant impact on optimal cardiovascular care. International and Canadian data have reported dramatically increased wait times for diagnostic tests and cardiovascular procedures, as well as associated increased cardiovascular morbidity and mortality. In the wake of the demonstrated ability to rapidly create critical care and hospital ward capacity, we advocate a different approach during the second and possible subsequent COVID-19 pandemic waves. We suggest an approach, informed by local data and experience, that balances the need for an expected rise in demand for health care resources to ensure appropriate COVID-19 surge capacity with continued delivery of essential cardiovascular care. Incorporating cardiovascular care leaders into pandemic planning and operations will help health care systems minimise cardiac care delivery disruptions while maintaining critical care and hospital ward surge capacity and continuing measures to reduce transmission risk in health care settings. Specific recommendations targeting the main pillars of cardiovascular care are presented: ambulatory, inpatient, procedural, diagnostic, surgical, and rehabilitation.

Guiding Cardiac Care During the COVID-19 Pandemic: How Ethics Shapes Our Health System Response.

The COVID-19 pandemic has raised ethical questions for the cardiovascular leader and practitioner. Attention has been redirected from a system that focuses on individual patient benefit toward one that focuses on protecting society as a whole. Challenging resource allocation questions highlight the need for a clearly articulated ethics framework that integrates principled decision making into how different cardiovascular care services are prioritized. A practical application of the principles of harm minimisation, fairness, proportionality, respect, reciprocity, flexibility, and procedural justice is provided, and a model for prioritisation of the restoration of cardiovascular services is outlined. The prioritisation model may be used to determine how and when cardiovascular services should be continued or restored. There should be a focus on an iterative and responsive approach to broader health care system needs, such as other disease groups and local outbreaks.

Cardiac Rehabilitation During the COVID-19 Era: Guidance on Implementing Virtual Care.

Cardiac rehabilitation programs across Canada have suspended in-person services as a result of large-scale physical distancing recommendations designed to flatten the COVID-19 pandemic curve. Virtual cardiac rehabilitation (VCR) offers an alternate mechanism of care delivery, capable of providing similar patient outcomes and safety profiles compared with centre-based programs. To minimize care gaps, all centres should consider developing and implementing a VCR program. The process of this rapid implementation, however, can be daunting. Centres should initially focus on the collation, utilization, and repurposing of existing resources, equipment, and technology. Once established, programs should then focus on ensuring that quality indicators are met and care processes are protocolized. This should be followed by the development of sustainable VCR solutions to account for care gaps that existed before COVID-19, and to improve cardiac rehabilitation delivery, moving forward. This article reviews the potential challenges and obstacles of this process and aims to provide pragmatic guidance to aid clinicians and administrators during this challenging time.

COVID-19 Pandemic: Global Impact and Potential Implications for Cardiovascular Disease in Canada.

BACKGROUND: The literature indicates that cardiovascular disease (CVD; including stroke), older age, and availability of health care resources affect COVID-19 case fatality rates (CFRs). The cumulative effect of COVID-19 CFRs in global CVD populations and the extrapolated effect on access to health care services in the CVD population in Canada are not fully known. In this study we explored the relationships of factors that might affect COVID-19 CFRs and estimated the potential indirect effects of COVID-19 on Canadian health care resources. METHODS: Country-level epidemiological data were analyzed to study the correlation, main effect, and interaction between COVID-19 CFRs and: (1) the proportion of the population with CVD; (2) the proportion of the population 65 years of age or older; and (3) the availability of essential health services as defined by the World Health Organization Universal Health Coverage index. For indirect implications on health care resources, estimates of the volume of postponed coronary artery bypass grafting, percutaneous coronary intervention, and valve surgeries in Ontario were calculated. RESULTS: Positive correlations were found between COVID-19 CFRs and: (1) the proportion of the population with CVD (ρ = 0.40; P = 0.001); (2) the proportion of the population 65 years of age or older (ρ = 0.43; P = 0.0005); and (3) Universal Health Coverage index (ρ = 0.27; P = 0.03). For every 1% increase in the proportion of the population 65 years of age or older or proportion of the population with CVD, the COVID-19 CFR was 9% and 19% higher, respectively. Approximately 1252 procedures would be postponed monthly in Ontario because of current public health measures. CONCLUSIONS: Countries with more prevalent CVD reported higher COVID-19 CFRs. Strain on health care resources is likely in Canada.

CONTEXTE: La littérature indique que les maladies cardiovasculaires (MCV, incluant les accidents vasculaires cérébraux), l'âge avancé et la facilité d'accès aux ressources de soins de santé ont une incidence sur les taux de létalité (TL) des cas de COVID-19. L'effet cumulatif du TL de la COVID-19 dans l'ensemble de la population atteinte de MCV et l'impact anticipé sur l'accès aux services de santé dans la population atteinte de MCV au Canada ne sont pas entièrement connus. Cette étude a exploré les liens entre les facteurs pouvant influencer le TL des cas de COVID-19 et a estimé le potentiel impact indirect de la COVID-19 sur les ressources de soins de santé au Canada. MÉTHODES: Les données épidémiologiques à l'échelle du pays ont été analysées pour étudier la corrélation, l'effet principal et l'interaction entre le TL de laCOVID-19 et : 1) la proportion de la population souffrant de MCV, 2) la proportion de la population ≥ 65 ans, et 3) l'accessibilité des services de santé essentiels tels que définis par l'indice de couverture sanitaire universelle (CSU) de l'Organisation Mondiale de la Santé. Pour les implications indirectes concernant les ressources de santé, des estimations du volume d'opération de pontages coronariens, d'interventions coronariennes percutanées et de chirurgies valvulaires reportées en Ontario ont été calculées. RÉSULTATS: Des corrélations positives ont été trouvées entre le TL de la COVID-19 et 1) la proportion de la population souffrant de MCV (ρ= 0,40, P = 0,001), 2) la proportion de la population ≥ 65 ans (ρ= 0,43, P = 0,0005), et 3) l'indice CSU (ρ= 0,27, P = 0,03). Pour chaque augmentation de 1 % de la proportion de la population ≥ 65 ans ou de la proportion de la population souffrant de MCV, le TL de la COVID-19 était respectivement supérieur de 9 % et 19 %. Environ 1 252 interventions seraient reportées chaque mois en Ontario en raison des mesures de santé publique actuelles. CONCLUSIONS: Les pays où les MCV sont plus répandues ont signalé un TL de la COVID-19 plus élevé. Il est probable que les ressources de soins de santé soient soumises à de fortes contraintes au Canada.

Guidance on Minimizing Risk of Drug-Induced Ventricular Arrhythmia During Treatment of COVID-19: A Statement from the Canadian Heart Rhythm Society.

The COVID-19 pandemic has led to efforts at rapid investigation and application of drugs which may improve prognosis but for which safety and efficacy are not yet established. This document attempts to provide reasonable guidance for the use of antimicrobials which have uncertain benefit but may increase risk of QT interval prolongation and ventricular proarrhythmia, notably, chloroquine, hydroxychloroquine, azithromycin, and lopinavir/ritonavir. During the pandemic, efforts to reduce spread and minimize effects on health care resources mandate minimization of unnecessary medical procedures and testing. We recommend that the risk of drug proarrhythmia be minimized by 1) discontinuing unnecessary medications that may also increase the QT interval, 2) identifying outpatients who are likely to be at low risk and do not need further testing (no history of prolonged QT interval, unexplained syncope, or family history of premature sudden cardiac death, no medications that may prolong the QT interval, and/or a previous known normal corrected QT interval [QTc]), and 3) performing baseline testing in hospitalized patients or those who may be at higher risk. If baseline electrocardiographic testing reveals a moderately prolonged QTc, optimization of medications and electrolytes may permit therapy. If the QTc is markedly prolonged, drugs that further prolong it should be avoided, or expert consultation may permit administration with mitigating precautions. These recommendations are made while there are no known effective treatments for COVID-19 and should be revisited when further data on efficacy and safety become available.