Retrograde Snaring for Left Ventricular Lead Placement in the Presence of a Persistent Left Superior Vena Cava.

Left ventricular lead positioning is technically demanding in cardiac resynchronization therapy (CRT) device implantation, especially in patients with complex cardiac venous anatomies. We report a case in which retrograde snaring was employed to successfully deliver the left ventricular lead through a persistent left superior vena cava for CRT implantation.

Women and Alcohol: Limitations in the Cardiovascular Guidelines.

Patients and physicians rely on evidence-based guidelines to guide alcohol consumption recommendations, but significant discrepancies in alcohol consumption limits are found between different international societies. Current American Heart Association (AHA) preventive management guidelines on hypertension, transient ischemic attack, stroke, and stable ischemic heart disease recommend sex-specific daily alcohol consumption limits which are inconsistent from other international society recommendations. In this focused review of current American Heart Association guidelines and their sources, we evaluate the evidence behind sex-specific alcohol consumption cut-offs. We found insufficient experimental and epidemiologic evidence to conclude that women should have a reduced daily alcohol consumption limit as compared to men; further studies are required to determine whether sex-specific differences exist in alcohol metabolism and its related cardiovascular impact.

The Effect of Sex on Door-to-Balloon Time in Patients Presenting With ST-Elevation Myocardial Infarction and Referred for Primary Percutaneous Coronary Intervention: A Systematic Review.

Timely reperfusion using primary percutaneous coronary intervention (pPCI) is the cornerstone of acute ST-elevation myocardial infarction (STEMI) management. We conducted a systematic review to examine the effect of sex on door-to-balloon (D2B) time and symptom-to-balloon (S2B) time. We observed longer D2B times and S2B times in female patients presenting with STEMI and referred for pPCI when compared to male patients. Future work is required to try and elucidate and mitigate sex-based front-line treatment delays for female STEMI patients.

Metabolomics Work Flow and Analytics in Systems Biology.

Metabolomics is an omics approach of systems biology that involves the development and assessment of large-scale, comprehensive biochemical analysis tools for metabolites in biological systems. This review describes the metabolomics workflow and provides an overview of current analytic tools used for the quantification of metabolic profiles. We explain analytic tools such as mass spectrometry (MS), nuclear magnetic resonance (NMR) spectroscopy, ionization techniques, and approaches for data extraction and analysis.

Fluoroless Catheter Ablation of Atrial Fibrillation: Integration of Intracardiac Echocardiography and Cartosound Module.

OBJECTIVE: To evaluate the feasibility, safety, and clinical efficacy of non-fluoroscopic radiofrequency catheter ablation of atrial fibrillation (AF) in comparison to traditional fluoroscopy-guided ablation in a local Canadian community cohort. METHODS: We retrospectively studied consecutive patients with paroxysmal and persistent AF undergoing pulmonary vein isolation (PVI) guided by intracardiac echocardiography (ICE) and Carto system (CartoSound module). ICE-guided PVI without fluoroscopy (Zero-fluoro group) was performed in 116 patients, and conventional fluoroscopy-guided PVI (Traditional group) was performed in 131 patients. RESULTS: Two hundred and forty-seven patients with AF (60.7% male; mean age: 62.2 ± 10.6 years; paroxysmal AF =63.1%) who underwent PVI were studied. Mean procedure times were similar between both groups (136.8±33.4 minutes in the zero-fluoro group vs. 144.3±44.9 minutes in the traditional group; p=0.2). Acute PVI was achieved in all patients. Survival from early AF recurrence was 85% and 81% in the zero-fluoro and traditional groups, respectively (p = 0.06). Survival from late AF recurrence (12-months) between the zero-fluoro and traditional groups was also similar (p=0.1). Moreover, there were no significant differences between complication rates, including hematoma (p = 0.2) and tamponade (p = 1),between both groups. CONCLUSIONS: Zero-fluoroscopy ICE and CartoSound-guided AF ablation may be safe and feasible in patients undergoing PVI compared to conventional fluoroscopy-guided ablation.

Perturbations in cardiac metabolism in a human model of acute myocardial ischaemia.

INTRODUCTION: Acute myocardial ischaemia and the transition from reversible to irreversible myocardial injury are associated with abnormal metabolic patterns. Advances in metabolomics have extended our capabilities to define these metabolic perturbations on a metabolome-wide scale. OBJECTIVES: This study was designed to identify cardiac metabolic changes in serum during the first 5 min following early myocardial ischaemia in humans, applying an untargeted metabolomics approach. METHODS: Peripheral venous samples were collected from 46 patients in a discovery study (DS) and a validation study (VS) (25 for DS, 21 for VS). Coronary sinus venous samples were collected from 7 patients (4 for DS, 3 for VS). Acute myocardial ischaemia was induced by transient coronary occlusion during percutaneous coronary intervention (PCI). Plasma samples were collected at baseline (prior to PCI) and at 1 and 5 min post-coronary occlusion. Samples were analyzed by Ultra Performance Liquid Chromatography-Mass Spectrometry in an untargeted metabolomics approach. RESULTS: The study observed changes in the circulating levels of metabolites at 1 and 5 min following transient coronary ischaemia. Both DS and VS identified 54 and 55 metabolites as significant (P < 0.05) when compared to baseline levels, respectively. Fatty acid beta-oxidation and anaerobic respiration, lysoglycerophospholipids, arachidonic acid, docosahexaenoic acid, tryptophan metabolism and sphingosine-1-phosphate were identified as mechanistically important. CONCLUSION: Using an untargeted metabolomics approach, the study identified important cardiac metabolic changes in peripheral and coronary sinus plasma, in a human model of controlled acute myocardial ischaemia. Distinct classes of metabolites were shown to be involved in the rapid cardiac response to ischemia and provide insights into diagnostic and interventional targets.

Successful implantation of a left ventricular lead in an anomalous coronary sinus.

We describe the case of a 56-year-old man who was referred for CRT implantation and found to have anomalous CS. Catheterization of the CS initially failed due to this anomaly. However, a single large posterior-lateral branch with diminutive CS in the atrioventricular groove allowed for successful implantation of the LV lead.

Importance of Polarity Reversal in Leads I/aVL in the Diagnosis of an Accessory Pathway Originating from the Aortomitral Continuity.

Accessory pathways (APs) are commonly located around the tricuspid and mitral annulus; however, they can be rarely seen in unusual locations like the aortomitral continuity (AMC), the right atrium to the right ventricular outflow region, and the left atrial appendage to left ventricle connection. Although several electrocardiogram algorithms have been proposed to localize the AP, the sensitivity of these algorithms is not high and they may fail to localize the mentioned unusual localizations. In this report, we describe a case of a 37-year-old man presenting with an AP originating from the AMC, which was successfully ablated.

Acute heart failure in pregnancy: importance of a timely multidisciplinary approach to recognition and management.

Increased cardiovascular demands of pregnancy may unmask occult diseases, such as dilated cardiomyopathy or valvular stenosis, or precipitate peripartum cardiomyopathy. We report a case of the emergency management and delivery of a young pregnant woman who presented with acute decompensated heart failure that was not immediately recognized. An emergency transfer to a tertiary care institution was arranged. Once diagnosed, the patient received multidisciplinary care shared between cardiologists, obstetricians, cardiac anesthetists, a neonatologist, and a midwife, resulting in good maternal and fetal outcomes.

Arrhythmias and electrocardiographic findings in Coronavirus disease 2019: A systematic review and meta-analysis.

BACKGROUND: Coronavirus disease 2019 (COVID-19) primarily causes lung infection, but recent studies have shown that cardiac involvement is associated with a worse prognosis. OBJECTIVES: We conducted a systematic review and meta-analysis to examine the prevalence of cardiac arrhythmias detected by the electrocardiogram and their relationships with adverse outcomes in patients with COVID-19. METHODS: PubMed and Google were searched for studies that reported on cardiac arrhythmias and/or examined the relationship between arrhythmias and adverse outcomes. RESULTS: Thirty studies with 12,713 participants were included in the systematic review, and 28 studies (n = 12,499) in the meta-analysis. The mean age was 61.3 ± 16.8 years; 39.3% were female. In 25 studies with 7578 patients, the overall prevalence of cardiac arrhythmias was 10.3% (95% confidence interval [CI]: 8.4%-12.3%). The most common arrhythmias documented during hospitalization were supraventricular arrhythmias (6.2%, 95% CI: 4.4%-8.1%) followed by ventricular arrhythmias (2.5%, 95% CI: 1.8%-3.1%). The incidence of cardiac arrhythmias was higher among critically ill patients (relative risk [RR]: 12.1, 95% CI: 8.5-17.3) and among non-survivors (RR: 3.8, 95%, CI: 1.7-8.7). Eight studies reported changes in the QT interval. The prevalence of QTc > 500 ms was 12.3% (95% CI: 6.9%-17.8%). ST-segment deviation was reported in eight studies, with a pooled estimate of 8.7% (95% CI: 7.3% to 10.0%). CONCLUSION: Our meta-analysis showed that QTc prolongation, ST-segment deviation, and various other cardiac arrhythmias were observed in patients hospitalized with COVID-19. The presence of cardiac arrhythmias was associated with a worse prognosis.

Diathermy-induced Ventricular Fibrillation.

Diathermy is extensively used in patients for intracardiac device implant and extraction. While diathermy helps with adequate hemostasis, it may rarely be associated with fatal dysrhythmias. We report a case of diathermy-induced ventricular fibrillation during device extraction. The case highlights the importance and supports the involvement of a defibrillation facility during pacemaker revisions requiring diathermy.

Evaluation and Management of Asymptomatic Bradyarrhythmias.

Asymptomatic bradyarrhythmias involving sinus node dysfunction and atrioventicular blocks are frequently noted in clinical practice. Its prevalence is expected to rise as devices that are developed for monitoring cardiac rhythm for longer duration become more widely available. Episodes of bradyarrhythmia that are asymptomatic are considered to have a benign course compared with those that cause symptoms and do not necessitate further treatment. However, in certain cases, they can be a harbinger of future symptoms or cardiac manifestations of systemic diseases. The evaluation and risk stratification of individuals presenting with asymptomatic bradyarrhythmias is important not only for preventing implantation of unnecessary permanent pacing devices but also for reducing significant morbidity by implementing proper treatment as required. In this article, we will review the current evidence on the pathophysiology, diagnosis, evaluation and management of patients with asymptomatic bradyarrhythmias.

Value of electrocardiography in coronavirus disease 2019 (COVID-19).

In December 2019, reports of an unknown pneumonia not responsive to traditional treatments arose in Wuhan, China. The pathogen was subsequently identified as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), known to be responsible for the coronavirus disease-2019 (COVID-19) illness, and public health emergency of international concern was declared by the World Health Organization. There is increasing awareness of the cardiovascular manifestations of COVID-19 disease, and the adverse impact of cardiovascular involvement on its prognosis. In this setting, the electrocardiogram (ECG) is one of the leading tools to assess the extent of cardiac involvement in COVID-19 patients, due to its wide disponibility, low cost, and the possibility of remote evaluation. In this article, we review the role of the ECG in the identification of cardiac involvement in COVID-19, highlighting relevant clinical implications.

Rate-dependent aberrancy and cardiac resynchronization therapy.

Left bundle branch block (LBBB) can result in significant dyssynchrony in left ventricular (LV) contraction, ultimately leading to cardiac remodeling. LBBB can be rate dependent and may appear with LV systolic dysfunction. Cardiac resynchronization therapy (CRT) has been demonstrated to improve hemodynamics as well as clinical symptoms in patients with LBBB. We describe the case of a 57-year-old man who underwent CRT implantation due to exertional dyspnea, rate-dependent LBBB, and impaired left LV systolic function.

Successful leadless pacemaker implantation in a patient with profound bradycardia following transcatheter aortic valve replacement and mitral valve-in-valve procedure.

Leadless pacemakers provide a potential alternative to conventional transvenous pacemakers for patients undergoing high-risk transcatheter valve replacement procedures. This is a description of a successful leadless pacemaker implantation in a 51-year-old woman who developed profound bradycardia following a transcatheter aortic valve replacement and mitral valve-in-valve procedure.

Canada-wide mixed methods analysis evaluating the reasons for inappropriate emergency department presentation in patients with a history of atrial fibrillation: the multicentre AF-ED trial.

OBJECTIVES: The primary objective of this study was to ascertain the reasons for emergency department (ED) attendance among patients with a history of atrial fibrillation (AF). DESIGN: Appropriate ED attendance was defined by the requirement for an electrical or chemical cardioversion and/or an attendance resulting in hospitalisation or administration of intravenous medications for ventricular rate control. Quantitative and qualitative responses were recorded and analysed using descriptive statistics and content analysis, respectively. Random effects logistic regression was performed to estimate the OR of inappropriate ED attendance based on clinically relevant patient characteristics. PARTICIPANTS: Participants ≥18 years with a documented history of AF were approached in one of eight centres partaking in the study across Canada (Ontario, Nova Scotia, Alberta and British Columbia). RESULTS: Of the 356 patients enrolled (67±13, 45% female), the majority (271/356, 76%) had inappropriate reasons for presentation and did not require urgent ED treatment. Approximately 50% of patients(172/356, 48%) were driven to the ED due to symptoms, while the remainder presented on the basis of general fear or anxiety (67/356, 19%) or prior medical advice (117/356, 33%). Random effects logistic regression analysis showed that patients with a history of congestive heart failure were significantly more likely to seek urgent care for appropriate reasons (p=0.03). Likewise, symptom-related concerns for ED presentation were significantly less likely to result in inappropriate visitation (p=0.02). When patients were surveyed on alternatives to ED care, the highest proportion of responses among both groups was in favour of specialised rapid assessment outpatient clinics (186/356, 52%). Qualitative content analysis confirmed these results. CONCLUSIONS: Improved education focused on symptom management and alleviating disease-related anxiety as well as the institution of rapid access arrhythmias clinics may reduce the need for unnecessary healthcare utilisation in the ED and subsequent hospitalisation. TRIAL REGISTRATION NUMBER: NCT03127085.