Successful ablation of a right concealed epicardial accessory pathway using ethanol infusion.

INTRODUCTION: This study describes a rare case of concealed epicardial accessory pathway (AP) successfully ablated using ethanol infusion (EI) through a variant vessel connecting the right atrium (RA) and the right ventricle (RV) surface. METHODS AND RESULTS: A 58-year-old male referred to our hospital for prior failed AP ablation. Cardiac-enhanced computerized tomography scan showed there was a variant vessel at the tip of right atrial appendage and a pulmonary artery (PA)-RA fistula at the roof of RA. The earliest activation was present at the site of the PA-RA fistula. A selective angiography showed that a small branch of the variant vessel covered the earliest excitation site of the AP. EI into this branch successfully repressed the AP without any recurrences within a follow-up period of 3 months. CONCLUSION: Endocardial ablation is challenging for epicardial APs related to cardiac structural variations. If small vascular branches near the earliest activation site can be found, EI can successfully ablate these types of epicardial APs.

Ischemic ventricular tachycardia presenting as a narrow complex tachycardia.

This report describes a patient presenting with a narrow complex tachycardia in the context of prior myocardial infarction and impaired ventricular function. Electrophysiological studies confirmed ventricular tachycardia and activation and entrainment mapping demonstrated a critical isthmus within an area of scar involving the His-Purkinje system accounting for the narrow QRS morphology. This very rare case shares some similarities with upper septal ventricular tachycardia seen in patients with structurally normal hearts, but to our knowledge has not been seen previously in patients with ischemic heart disease.

Electrophysiologic diagnosis of narrow and wide complex tachyarrhythmias.

Establishing the precise mechanism of cardiac arrhythmias in the electrophysiology laboratory is one of the main requisites for a successful and safe ablation. This article provides an organized approach to the differential diagnosis of narrow and wide complex tachycardias based on the analysis of electrical activation patterns, followed by specific pacing maneuvers in each case.

Narrow Complex Tachycardias.

Narrow-complex tachycardias are commonly seen on shift in the emergency department. Although a portion of patients present with hemodynamic instability because of arrhythmia, it is important to know that the tachycardia can be a result of an underlying condition. Rapid identification of the type and etiology of the arrhythmia is vital to directing appropriate management strategies and disposition decisions.

Taken to heart-arrhythmic potential of heart-leaf sida, a banned ephedrine alkaloid: a case report.

BACKGROUND: Ephedra and ephedrine alkaloids were commonly used in herbal supplements before being prohibited by the European Commission and US Food and Drug Administration. However, ongoing, unknowing use by consumers can lead to potential adverse cardiovascular effects, such as arrhythmias. CASE SUMMARY: A 65-year-old-man with a history of idiopathic pulmonary fibrosis status post-right single lung transplant was admitted for dizziness and resting tachycardia. Electrocardiogram showed a narrow complex, long R-P tachycardia with upright P-waves in lead V 1. An initial workup suggested an arrhythmia associated with the consumption of an herbal supplement containing heart-leaf sida, a banned botanical ephedrine alkaloid. After the supplement was discontinued, the patient's heart rate abruptly decreased without other intervention. Electrocardiogram showed a change in P-wave morphology in lead V 1 from upright to biphasic (+/-) after conversion to normal sinus rhythm. Thus, a diagnosis of atrial tachycardia originating at or near the donor right superior pulmonary vein was favoured. DISCUSSION: Atrial tachycardia can be precipitated by the proarrhythmic effects of ephedrine alkaloids, especially in patients with underlying risk factors and susceptible atrial anatomical substrate post-lung transplantation. Despite being banned by the European Union and the USA, ephedrine alkaloids continue to be used in over-the-counter herbal supplements and may go undetected by consumers. Ongoing vigilance for ephedrine alkaloids, more rigorous regulation, and active patient education can help reduce potential cardiovascular adverse events.

Utilizing the Cool-Down Phenomenon to Differentiate Supraventricular Tachycardias in a Patient with COVID-19 Infection.

A 63-year-old male patient with a history of hypertension, diabetes mellitus type 2, prostate cancer and class two obesity was admitted for encephalopathy. During his hospital stay he developed narrow complex tachycardia and it was difficult to definitively diagnose the underlying arrhythmia. Observation of the cool down phenomenon on telemetry strip allowed us to make the diagnosis of atrial tachycardia and elegantly rule out other causes. We report this interesting case of narrow complex tachycardia.

Supraventricular tachycardia: An overview of diagnosis and management.

Supraventricular tachycardia (SVT) is a common cause of hospital admissions and can cause significant patient discomfort and distress. The most common SVTs include atrioventricular nodal re-entrant tachycardia, atrioventricular re-entrant tachycardia and atrial tachycardia. In many cases, the underlying mechanism can be deduced from electrocardiography during tachycardia, comparing it with sinus rhythm, and assessing the onset and offset of tachycardia. Recent European Society of Cardiology guidelines continue to advocate the use of vagal manoeuvres and adenosine as first-line therapies in the acute diagnosis and management of SVT. Alternative therapies include the use of beta-blockers and calcium channel blockers. All patients treated for SVT should be referred for a heart rhythm specialist opinion. Long-term treatment is dependent on several factors including frequency of symptoms, risk stratification, and patient preference. Management can range from conservative, if symptoms are rare and the patient is low risk, to catheter ablation which is curative in the majority of patients.

Idiopathic Fascicular Left Ventricular Tachycardia.

Idiopathic left fascicular ventricular tachycardia (ILFVT) is characterized by right bundle branch block morphology and left axis deviation. We report a case of idiopathic left ventricular fascicular tachycardia in a young 31-year-old male patient presenting with a narrow complex tachycardia.

Emergency diagnosis and management of pediatric arrhythmias.

True emergencies due to unstable arrhythmias in children are rare, as most rhythm disturbances in this age group are well-tolerated. However, presentation to an emergency department with symptoms of palpitations, fatigue and/or syncope is much more common. Sinus tachycardia is by far the most commonly reported arrhythmia, followed by supraventricular tachycardia. Emergency physicians should be prepared for diagnosis and to acutely manage various types of arrhythmias seen in children, to assess the need for further diagnostic testing, and to determine whether cardiology evaluation and follow-up are needed. This article is intended to provide diagnostic and management guidelines of the most common types of arrhythmias seen in children with structurally normal hearts as well as those associated with congenital heart disease and cardiomyopathies.