Yellow phosphorus-induced Brugada phenocopy

Background

Metallic phosphides (of aluminum and phosphide) and yellow phosphorus are commonly used rodenticide compounds in developing countries. Toxicity of yellow phosphorus mostly pertains to the liver, kidney, heart, pancreas and the brain. Cardiotoxicity with associated Brugada ECG pattern has been reported only in poisoning with metallic phosphides.

Brugada phenocopy in a patient with unstable angina and three-vessel coronary artery disease

A 52-year-old male was admitted with unstable angina and three-vessel coronary artery disease. Electrocardiography (ECG) changes consistent with type-1 Brugada ECG pattern were noted during admission. The patient was asymptomatic for syncope and had no family history of sudden cardiac death, ICD implantation, and Brugada syndrome. After coronary by-pass graft the Brugada ECG pattern resolved, and ajmaline test did not elicit type-1 ECG pattern, confirming the suspicion of Brugada phenocopy.     

Brugada phenocopy secondary to extensive inferior wall ischemia induced by coronary steal effect

The diagnosis of Brugada syndrome is usually made with a typical ECG pattern. However, different disorders can emulate this pattern (Brugada phenocopies). Pathophysiologic mechanisms underlying this phenomenon remain controversial. We describe the development of type‐1 Brugada ECG pattern associated with extensive coronary steal effect during myocardial perfusion scintigraphy. Proximal occlusion of the right coronary artery and severe proximal stenosis in distally occluded left circumflex artery were confirmed by coronary angiogram. Brugada ECG pattern can be a reversible sign associated with inferior left ventricular and right ventricular ischemia. Its presence during acute ischemia deserves appropriate risk stratification.     

Brugada phenocopy associated with left ventricular aneurysm

Brugada phenocopies (BrP) are clinical entities that are characterized by ECG patterns identical to those of Brugada syndrome, but are the result of various clinical conditions. We describe the case of a 41-year-old male who exhibited BrP due to a left ventricular aneurysm in the context of chronic coronary artery disease.     

Type 1 Brugada phenocopy in a patient with acute pericarditis

We herein describe a case of an acute pericarditis, in which type 1 Brugada phenocopy (BrP) was documented. The patient was referred to our hospital due to severe chest pain. The twelve-lead electrocardiogram (ECG) on admission showed type 1 Brugada ECG pattern (coved-type) in the precordial leads. Echocardiography only showed mild pericardial effusion. However, his ST segment elevation returned to normal and chest discomfort disappeared 3?weeks later. Our report addresses the possibility that the coved-type ST-segment elevation cannot be a sensitive finding for Brugada syndrome (BrS). Detailed tests are anyway needed to make appropriate diagnostic and therapeutic decisions.     

Brugada phenocopy: A new electrocardiogram phenomenon

Brugada phenocopies(BrP) are clinical entities that are etiologically distinct from true congenital Brugada syndrome. BrP are characterized by type 1 or type 2 Brugada electrocardiogram(ECG) patterns in precordial leads V1-V3. However, BrP are elicited by various un-derlying clinical conditions such as myocardial ischemia, pulmonary embolism, electrolyte abnormalities, or poor ECG filters. Upon resolution of the inciting underlying pathological condition, the BrP ECG subsequently nor-malizes. To date, reports have documented BrP in the context of singular clinical events. More recently, recur-rent BrP has been demonstrated in the context of re-current hypokalemia. This demonstrates clinical repro-ducibility, thereby advancing the concept of this new ECG phenomenon. The key to further understanding the pathophysiological mechanisms behind BrP requires experimental model validation in which these phenom-ena are reproduced under strictly controlled environ-mental conditions. The development of these validation models will help us determine whether BrP are tran-sient alterations of sodium channels that are not repro-ducible with a sodium channel provocative test or al-ternatively, a malfunction of other ion channels. In this editorial, we discuss the conceptual emergence of BrP as a new ECG phenomenon, review the progress made to date and identify opportunities for further investiga-tion. In addition, we also encourage investigators that are currently reporting on these cases to use the term BrP in order to facilitate literature searches and to help establish this emerging concept.     

Brugada phenocopy associated with diabetic ketoacidosis in two pediatric patients

Two patients without cardiac history demonstrated type 1 Brugada pattern during hospitalization for diabetic ketoacidosis (DKA). Both patients had normalization of their ECGs after treatment of marked electrolyte abnormalities and metabolic acidosis. In this report, we describe two cases of Brugada phenocopy associated with DKA in children.     

Brugada Phenocopy Clinical Reproducibility Demonstrated by Recurrent Hypokalemia

Brugada phenocopies (BrP) are clinical entities that are etiologically distinct from true congenital Brugada syndrome (BrS). BrP are characterized by type 1 or type 2 Brugada electrocardiogram (ECG) patterns in precordial leads V₁–V₃; however, BrP are elicited by various underlying clinical conditions such as electrolyte disturbances, myocardial ischemia, or poor ECG filters. In this report, we describe the first case of clinically reproducible BrP which is important to the conceptual evolution of BrP.     

Pectus excavatum: Right ventricular compromise with orthostatic syndrome and Brugada phenocopy

Pectus excavatum (PEXT) consists of an overgrowth of the chondral region with posterior displacement of the inferior part of the sternum, resulting in a concave chest deformity. Characteristic clinical and imaging findings may occur, depending on the compression that right cardiac chambers suffer, when squeezed between the sternum and the column vertebrae.     

Brugada Phenocopy: New Terminology and Proposed Classification

Brugada syndrome is a channelopathy characterized on ECG by coved ST‐segment elevation (≥2 mm) in the right precordial leads and is associated with an increased risk of malignant ventricular arrhythmias. The term Brugada phenocopy is proposed to describe conditions that induce Brugada‐like ECG manifestations in patients without true Brugada syndrome. An extensive review of the literature identified case reports that were classified according to their suspected etiological mechanism. Future directions to learn more about these intriguing cases is discussed.     

Methods for Improving the Diagnosis of a Brugada ECG Pattern

Brugada syndrome (BrS) is an inherited channelopathy that predisposes individuals to malignant arrhythmias and can lead to sudden cardiac death. The condition is characterized by two electrocardiography (ECG) patterns: the type‐1 or “coved” ECG and the type‐2 or “saddleback” ECG. Although the type‐1 Brugada ECG pattern is diagnostic for the condition, the type‐2 Brugada ECG pattern requires differential diagnosis from conditions that produce a similar morphology. In this article, we present a case that is suspicious but not diagnostic for BrS and discuss the application of ECG methodologies for increasing or decreasing suspicion for a diagnosis of BrS.     

Accelerated Idioventricular Rhythm Unmasking the Brugada Electrocardiographic Pattern

It has recently been reported that a high‐degree right bundle branch block (RBBB) may conceal the electrocardiographic manifestations of the Brugada ECG pattern. An 82‐year‐old with recent onset palpitations was seen in clinic. The resting ECG showed sinus rhythm, high‐degree RBBB, and an irregular idioventricular rhythm. Some fusion beats between sinus rhythm and idioventricular rhythm occurred spontaneously depicting incomplete RBBB pattern and a clear cut elevation of the ST‐segment was unveiled, giving rise to a suspicious Brugada ECG pattern. The mechanisms and implications of these findings are discussed.     

Brugada Phenocopy Induced by Electrolyte Disorder: A Transient Electrocardiographic Sign

Brugada syndrome (BrS) is an important cause of sudden cardiac death (SCD) with well‐defined ST‐segment elevation patterns on V₁–V₃. Observation of BrS‐Type‐electrocardiogram (ECG) patterns in medical conditions without true BrS is called “Brugada Phenocopy” (BrP). We present a case of 61‐year‐old male patient with hyperkalemia, hyponatremia, and BrS‐Type‐1 ECG pattern in the setting of acute postrenal failure. He was denying any syncope or family history of SCD. With normalization of electrolyte levels, BrS‐Type‐1‐ECG resolved. Electrolyte disturbances are one of the most common reasons of BrP. Being aware of BrPs and differentiating from an unmasked BrS‐ECG pattern could prevent patients from lethal consequences and unnecessary treatments.     

Long-term follow-up in patients with Brugada Syndrome in South China

ObjectiveTo evaluate the presence of Brugada electrocardiogram (ECG) pattern, clinical characteristics, treatment, and long‐term prognosis of Brugada syndrome in southern Chinese population.MethodsThis prospective study consisted of a consecutive series of patients with diagnostic coved type I Brugada ECG pattern at baseline between January 2007 and February 2020. Histories of symptoms including ventricular tachycardia (VT)/ventricular fibrillation (VF) episode, syncope, and family history of Brugada Syndrome (BrS) or unexplained sudden cardiac death were collected. Electrophysiological study and implantable cardioverter‐defibrillator (ICD) were performed. All patients included in this study were followed up in the outpatient department every 6 months after baseline evaluation. Occurrences of syncope, VF, and sudden death were independently analyzed by two cardiologists.Results45 (56.3%) patients were diagnosed with BrS. During a mean follow‐up of 7.9 ± 3.6 years, six patients had experienced documented VF/sudden cardiac death (SCD) or recurrent syncope. Two patients experienced episodes of syncope more than once. Two patients experienced onset of electrical storm with a total of 11 episodes of VF. There were 50% of these events occurring in fever status. One of patient with BrS died of SCD.ConclusionThere was a very low prevalence of Brugada syndrome in southern Chinese population. The risk of arrhythmic events was low in asymptomatic patients. ICD was high effective in preventing SCD without adverse device outcome in long‐term follow‐up. Fever can lead to predispose to malignant arrhythmia, and aggressive treatment of febrile state in Brugada syndrome was recommended.