Brugada phenocopy: morphological classification and importance of provocative testing

Brugada phenocopy in fulminant eosinophilic myocarditis: a case series

Background

Brugada phenocopy (BrP) is a condition that induces reversible Brugada-like electrocardiographic (ECG) changes in patients without true Brugada syndrome. We present two cases of fulminant eosinophilic myocarditis that showed Type 1 Brugada ECG changes in the early phase of the clinical course.

Case summary

Case 1 was a 76-year-old man who developed fulminant eosinophilic myocarditis with ventricular tachycardia while hospitalized for heart failure. Case 2 was a 60-year-old man who presented with cardiogenic shock and was diagnosed with fulminant eosinophilic myocarditis. Both patients showed a Type 1 Brugada ECG at onset, and their ventricular function was greatly reduced. Regarding mechanical circulatory support, Case 1 was treated with venous-arterial extracorporeal membrane oxygenation and intra-aortic balloon pumping. Case 2 had venous-arterial extracorporeal membrane oxygenation and Impella CP insertion. Steroid therapy was introduced in both cases. In Case 1, the Type 1 Brugada ECG took 7 days to improve. Left ventricular function improved with time but right heart function was poor and right heart enlargement remained. In Case 2, the Type 1 Brugada ECG improved on the second day, and left and right heart function improved over time.

Discussion

We report two cases of fulminant eosinophilic myocarditis with Brugada-like ECG and severe right heart dysfunction. BrP in acute myocarditis may be an indicator of right heart failure and an important ECG marker in determining the indication for mechanical circulatory support and improvement of right heart function.

Brugada phenocopy vs. Brugada syndrome: Delineating the differences for optimal diagnosis and management

Brugada syndrome (BrS) is a genetic disorder known for its characteristic electrocardiogram (ECG) patterns and increased risk of sudden cardiac death. Brugada phenocopy (BrP) presents similar ECG patterns but is distinguished by its reversible nature when the underlying conditions are resolved. This article delineates the intricacies of BrP, emphasizing its etiology, clinical presentation, diagnosis, treatment, and prognosis. The article categorizes BrP based on various underlying causes, including metabolic disturbances, myocardial infarction, and mechanical compression, among others. It also underscores the critical importance of differentiating BrP from BrS to avoid misdiagnosis and inappropriate treatment, such as unnecessary implantation of cardioverter-defibrillators. The reversible aspect of BrP underlines the necessity for an etiology-specific approach to treatment, which not only prevents cardiac death but also highlights the significance of understanding the dynamic nature of ECG patterns. Through an exploration of case studies and current research, this review advocates for increased awareness and further investigation into BrP. It aims to enhance the diagnostic accuracy and management strategies, thereby improving the prognosis for patients presenting with Brugada-like ECG patterns. The review culminates in a call for further research to close existing knowledge gaps and improve patient outcomes.

Brugada Phenocopy Induced by Hypovolemic Hyponatremia

Brugada syndrome (BrS) is a hereditary channelopathy caused by an autosomal dominant mutation in the cardiac sodium channel gene SCN5A alpha subunit. In individuals without structural heart disease, the risk of sudden cardiac death (SCD) increases in this channelopathy with ST-segment elevation in V1-3 precordials. Brugada phenocopy (BrP) is a condition in which transient ST-segment elevations are observed, mimicking BrS electrocardiographic changes, which can occur with electrolyte and metabolic disorder scenarios. In this study, we share a case of BrP that occurred due to hypovolemic hyponatremia and recovered spontaneously with the correction of electrolyte disturbance.

Captagon-induced Brugada phenocopy: A report of two cases

Brugada phenocopies (BrP) represent electrocardiogram changes identical to those of true congenital Brugada syndrome but are induced by reversible clinical conditions. Previous cases have been reported in patients following recreational drug use. This report presents two cases of type 1B BrP associated with Fenethylline abuse, a recreational drug known by its trade name, Captagon.

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.

Brugada Phenocopy Induced by Recreational Drug Use

Recreational drugs are commonly abused in all age groups. Intoxication with these substances can induce silent but significant electrocardiographic signs which may lead to sudden death. In this case study, we present a 49-year-old male with no medical comorbidities who came to the emergency department requesting opioid detoxification. Toxicology screen was positive for cocaine, heroin, and cannabis. Initial electrocardiogram (EKG) showed features of a Brugada pattern in the right precordial leads, which resolved within one day into admission. This presentation is consistent with the recently recognized clinical entity known as Brugada phenocopy.

A Case of Type I and II Brugada Phenocopy Unmasked in a Patient with Normal Baseline Electrocardiogram (ECG)

BACKGROUND Brugada pattern on electrocardiogram (ECG) is seen when there are at least 2 mm J-point elevation and 1 mm ST-segment elevation in two or more of the right precordial leads, with right bundle-branch block (RBBB)-like morphology. Elevation of a coved-type shape in leads V1 and V2 is consistent with type I Brugada pattern, whereas elevation of a saddle-back configuration distinguishes type II Brugada. If accompanied by life-threatening arrhythmias or sudden cardiac death, Brugada syndrome (BrS) is diagnosed. The presence of Brugada ECG pattern in absence of the syndrome has come to be known as Brugada phenocopy (BrP). CASE REPORT We introduce a case of both Brugada type I and II patterns unmasked in a 28-year-old female with fever secondary to mastitis. Though fever-induced BrP is a universally known phenomenon, the presentation of both type I and II patterns presenting in a patient during a single hospitalization makes this case unique from others. The patient was brought to the emergency department after experiencing a syncopal episode that appeared classically vasovagal in nature. Once her fever resolved, her baseline ECG showed no abnormalities. CONCLUSIONS Though Brugada ECG pattern may be very alarming, especially after syncope, appropriate management in the case of a fever-induced event would consist of observation with cardiac monitoring, immediate treatment of fever with antipyretics, and antibiotics for suspected infection. Close follow-up by a cardiologist as an outpatient is imperative to further ascertain if the patient is at high risk of life-threatening arrhythmias, significant for BrS.

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 during right coronary artery dissection

CASE PRESENTATION

A 68-year-old female presented with non-ST-segment elevation myocardial infarction, and urgency coronary angiography was performed. The procedure was complicated with right coronary artery dissection leading to type-1 Brugada ECG pattern.

DISCUSSION

Brugada phenocopies (BrP) are clinical entities that present with electrocardiograms identical to those found in Brugada Syndrome (BrS) but are the result of different medical conditions. This report provides evidence that atypical causes of myocardial ischemia may induce BrP. Appropriate electrocardiogram and clinical differentiation of Brugada phenocopy from true Brugada syndrome may prevent unnecessary treatments. Although patients with true high-risk BrS are candidates for ICD therapy, the natural history of BrP remains unknown and seems to be more benign, depending on the severity of the underlying condition.

Brugada phenocopy in a patient with acute pulmonary embolism presenting with recurrent syncope

Brugada phenocopy (BrP) refers to a group of clinical conditions that have etiologies distinct from Brugada syndrome (BrS). Although both demonstrate features of ST-segment elevation in the right precordial leads on the electrocardiogram (ECG), one must be distinguished from the other as their treatment options are different. We report a male patient who presented with recurrent syncope with a Brugada and a S1Q3T3 pattern on the ECG. Acute pulmonary embolism (APE) complicated by BrS was suspected. Twenty-four hours Holter monitoring did not demonstrate any evidence of ventricular arrhythmias. Computed tomography pulmonary angiogram confirmed the presence of an APE. He was treated with low molecular weight heparin and a repeat ECG taken the next day showed resolution of the Brugada and S1Q3T3 patterns. This case report illustrates that APE and BrS can present with similar clinical and electrocardiographic features of recurrent syncope and Brugada pattern, respectively.

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.

Brugada Phenocopy as a Dynamic Electrocardiographic Pattern during Acute Anterior Myocardial Infarction

Brugada phenocopies represent some unusual clinical cases with identical characteristics to Brugada syndrome (BrS) elicited by various clinical circumstances. We report the case of a woman exhibiting "Brugada Phenocopy" during an acute anterior myocardial infarction, highlighting differential diagnosis with true BrS and discussing possible mechanisms underlying its dynamic ECG pattern.

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.

Massive pulmonary embolism mimicking electrocardiographic pattern of Brugada syndrome

Brugada syndrome is an inherited heart disease without structural abnormalities that is thought to arise as a result of accelerated inactivation of Na channels and predominance of transient outward K current to generate a voltage gradient in the right ventricular layers. Brugada syndrome occurs in patients with structurally normal heart and predisposes patients to malignant ventricular arrhythmias. Acute pulmonary embolism has been associated with a variety of electrocardiograms,and rarely, it may mimic electrocardiographic pattern of Brugada syndrome and this condition was defined as Brugada phenocopy.

Ischemia-induced Brugada phenocopy

A 65-year-old man with history of schizoaffective disorder was admitted with a suspicion for syncope. ECG changes consistent with type-1 Brugada pattern were noted on admission. A personal history of angina was reported but a family history of sudden cardiac death or ICD implantation was denied. A fixed perfusion defect and hypokinesis of the distal infero-lateral wall were reported on a pharmacological stress test prompting a coronary angiography. A stent was deployed across a 95% stenosis of the dominant mid right coronary artery with satisfactory results. Resolution of the Brugada type pattern was noted on ECGs repeated after the stenting.

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