Brugada ECG Pattern Research Articles

Single Oral Flecainide Dose to Unmask Type 1 Brugada Syndrome Electrocardiographic Pattern

Brugada syndrome (BrS) includes a group of patients with a typical pattern of ST segment elevation in right precordial leads who are at risk for sudden cardiac death. The electrocardiogram pattern may be intermittent and unmasked by sodium channel blockers. The main objective of this study is to describe a serie of consecutive patients in whom oral administration of flecainide was used to unmask BrS type I electrocardiographic pattern. We prospectively studied 14 symptomatic (palpitations/syncope) patients referred to our laboratory presenting a suggestive but not diagnostic Brugada ECG or family history of sudden death. Single oral dose of flecainide 400 mg was administered. Resting 12-lead ECG with upper and standard right precordial leads were performed after flecainide administration at 15, 30, 60 and 90 min and hourly until ECG became normal. Median age was 37.5 years (range= 22-50). None of them had structural heart disease. In 7 patients (50%) the typical coved-type ECG pattern of BrS was unmasked. PR interval, QRS duration and QTc median difference after-before test was 20 msec (min-max= -17-+57), 21 ms (min-max= 0 to +59) and 20 ms (min-max= -11-+77), respectively. There were no episodes of AV block, atrial or ventricular tachyarrhythmia. In our experience we found that oral administration of flecainide in a single dose of 400 mg is useful to unmask type 1 Brugada electrocardiographic pattern.

Brugada syndrome in a family with a high mortality rate: a case report

IntroductionBrugada syndrome is a hereditary arrhythmia characterized by a specific electrocardiographic pattern and an increased risk of sudden cardiac death, with an apparent absence of structural abnormalities or ischemic heart disease. To date, mutations in the sodium channel, voltage-gated, type V, alpha subunit gene and glycerol-3-phosphate dehydrogenase 1-like gene are estimated to account for approximately 28% of Brugada syndrome probands.Case presentationWe report the case of a 32-year-old mixed-race Brazilian man who is sodium channel, voltage-gated, type V, alpha subunit gene and glycerol-3-phosphate dehydrogenase 1-like gene mutation-negative with a type 1 Brugada electrocardiographic pattern and a history of high family mortality, including five sudden deaths among relatives of whom four were first-degree relatives.ConclusionTo the best of our knowledge, this is the first case of a patient who has Brugada syndrome and a history of sudden death in four first-degree family members. This case report reinforces the evidence that genetic studies are of limited use while determining risk but remain helpful for diagnosis, and that diagnosis via electrocardiography is of great importance in preventing adverse events and stratifying risk. Although there are several technologically advanced diagnostic tools, they might not be accessible in small towns and hospitals; however, a basic diagnostic tool like electrocardiography is easily accessible.

Possible Brugada Phenocopy Induced by Hypokalemia in a Patient with Congenital Hypokalemic Periodic Paralysis

5. Anselm DD, Baranchuk A. Brugada Phenocopy Emerging as a New Concept. Rev Esp Cardiol. 2013;66(9):755. References DOI: 10.5935/abc.20130249 Dear Editor, We read with great interest the case report by Gazzoni et al1 regarding a Brugada ECG pattern induced by hypokalemia. This paper is important because it contributes to the growing body of literature describing Brugada Phenocopies (BrP)2-5. Briefly, BrP are characterized by ECG patterns that are identical to type-1 or type-2 Brugada ECG patterns despite the absence of true congenital Brugada Syndrome (BrS). BrP are induced by various clinical circumstances including: hypokalemia, hyperkalemia, hypothermia, myocardial ischemia, and pulmonary embolism. We have established six etiological categories of BrP2-4 along with a systematic approach to diagnose BrP3 by excluding sodium channel dysfunction in the myocardium. The presented case by Gazzoni et al1 would possibly qualify under category (i) metabolic conditions; however, further analysis of this case report is required. Specifically, this is the first report of a possible BrP induced by hypokalemia in association with hypokalemic periodic paralysis (HPP). Patients with HPP are known to have gene mutations resulting in abnormalities of either dihydropyridine-sensitive calcium channels or sodium channels (SCN4A) in skeletal muscles. Patients with true congenital BrS have mutations in the myocardial sodium channels (SCN5A) and the association in this patient is most intriguing and remains speculative. The type-1 “coved” Brugada ECG pattern observed in this patient could have been induced by the transient serum hypokalemia (which would qualify this as a BrP) or there may be a congenital dysfunction in this patient’s sodium channels in both his skeletal muscles (HPP) and myocardium resulting in the ECG abnormalities. Therefore, we recommend to the authors that a myocardial provocative challenge with a sodium channel blocker such as procainamide, ajmaline, or flecainide be performed to rule out myocardial sodium channel dysfunction. In addition, we also suggest that future reports use the established term Brugada Phenocopy to provide consistency in the literature and facilitate future research.

183: Is myotonic dystrophy part of the Brugada syndrome? Results of ajmaline challenge in Steinert disease

Both type 1 Myotonic Dystrophy (Steinert disease) and Brugada syndrome may be complicated by conduction disturbances and sudden death. ST elevation in the right precordial leads is the hallmark of Brugada syndrome but may be seen in some myopathies. Mutations in DMPK gene in Steinert pts may lead to cytosolic accumulation of muted toxic RNA or altered alternate splicing of some RNA potentially causing sodium channel dysfunctions. The prevalence of Brugada ECG pattern in Steinert disease is unknown. we perform ajmaline challenge test (1 mg/kg over 5 min) during electrophysiological (EP) testing in a population of 44 Steinert disease pts (27 men, 41±15 years old) without ST elevation at baseline. Left ventricular EF was normal in each case. The presence of type 1 ST elevation (> 2 mm J elevation with coved ST and negative T wave) after ajmaline challenge was correlated to clinical, ECG and electrophysiological variables. 8 pts (18%) present type 1 ST elevation in the right precordial leads after ajmaline infusion. Brugada pattern was more often seen in men: 7/27 (26%) vs 1/17 (6%) (p=0.09). Patients with negative ajmaline test presented more often with fascicular block: 13/35 (27%) versus none (p=0.03). Brugada pattern was not correlated to age, symptoms, PR interval, QRS, QT or QTc durations, HV interval (at baseline or after ajmaline), presence of bundle branch block, of late potentials at SA-ECG or inducibility of ventricular arrhythmias at EP study. Nine pts were implanted with a pace maker and four with an ICD. Significant or symptomatic bradycardia did not happen in any non implanted pts, while only one pt presented with malignant ventricular arrhythmias during the 6.3±2.6 years follow-up (ventricular fibrillation with hypokaliemia in an ajmaline negative pt). Brugada ECG pattern can be elicited by class 1 drug in 18% of Steinert disease pts and especially in men. Presence of type 1 ST elevation under class 1 drug in Steinert disease do not seem to have some significant clinical or ECG correlations.

Letter to the Editor Brugada electrocardiographic pattern in carbon monoxide poisoning

Carbon monoxide (CO) poisoning is the most common type of accidental poisoning in the United States, contributing to an estimated 15,000 emergency department visits and 500 deaths in the United States each year [1]. The signs and symptoms of CO poisoning are diverse, ranging from headache, lethargy, dizziness, nausea and confusion to cardiac and neurological disturbances. Cardiovascular complications of CO poisoning include myocardial ischemia, left ventricular dysfunction, or arrhythmias. We report the first case of Brugada electrocardiographic pattern (BEP) in CO poisoning in the English literature.

Brugada Electrocardiographic Pattern and Seizure Induced by Propranolol Overdose

Since the first description of Brugada syndrome in 1992, it has become the focus of interest among cardiologists and Emergency Physicians. Apart from its inherited form associated with SCN5A gene mutation, the acquired or drug-induced form was a relatively new concept. Although many agents had been implicated for manifestation of Brugada electrocardiographic pattern, it was not commonly described among patients with propranolol overdose.

Brugada syndrome phenotype cardiac arrest in a young patient unmasked during the acute phase of amiodarone infusion: disclosure and aggravation of Brugada electrocardiographic pattern

We report a case of an outpatient cardiac arrest due to ventricular fibrillation and resuscitated with external automated defibrillator shocks in which acute amiodarone infusion unmasked a Brugada phenotype electrocardiographic pattern. Possible interferences by this drug and suitable therapeutic actions are discussed.

High-degree right bundle branch block obscuring the diagnosis of Brugada electrocardiographic pattern

This work was supported in part by the Fundacion de Investigaciones Cardiologicas Einthoven and the Consejo de Investigacion en Salud, Ministry of Public Health, Goverment of Buenos Aires. Address reprint requests and correpondence: Dr Pablo A. Chiale, MD, Division of Cardiology, Centro de rritmias Cardiacas of Buenos Aires City, Ramos Mejia Hospital, Facultad e Ciencias Medicas, Pontificia Universidad Catolica Argentina, “Santa aria de los Buenos Aires,” General Urquiza 609, 1221 Buenos Aires, rgentina. E-mail address: pablochiale@fibertel.com.ar.

Pseudo–Heart Block and Pseudo-Brugada Morphology From Signal-Averaging Artifact During Exercise Stress Testing

A 57-year-old woman with atypical chest pain presented for exercise stress testing with myocardial single-photon emission computed tomography perfusion imaging. The patient had a history of hypertension and hypothyroidism but no other history of coronary disease or risk factors. The patient's baseline ECG is shown in Figure 1, interpreted as incomplete right bundle-branch morphology. During exercise stress testing, apparent 2:1 A:V conduction occurred, as shown in Figure 2A. Physicians reading the exercise stress test also interpreted ST elevation most prominent in lead V1 as consistent with the type 1 Brugada ECG pattern.1 Intermittent 2:1 A:V block appeared to resolve at high heart rates in Figure 2B. The test was terminated, and the patient appeared to return to normal sinus rhythm conduction with resolution of the ST deviation, as in Figure 2C. She was referred to the electrophysiology service for consideration of pacemaker implantation. Figure 1. ECG tracing of the patient before stress testing. A magnified section of V1 is shown in the window . Although interpreted as incomplete right bundle-branch block by referring physicians, the QRS duration of <100 ms does not meet formal criteria for this diagnosis. The …

The value of a family history of sudden death in patients with diagnostic type I Brugada ECG pattern

The value of a family history of sudden death in patients with diagnostic type I Brugada ECG pattern

Brugada ECG pattern: a physiopathological prospective study based on clinical, electrophysiological, angiographic, and genetic findings

Introduction: Brugada syndrome (BrS) is considered a primary electrical disease. However, morphological abnormalities have been reported and localized arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C) may mimic its phenotype, raising the question of an overlap between these two conditions and making difficult the therapeutic management of patients with borderline forms. The main objective of this study was to assess prospectively the prevalence of BrS and ARVD/C on the basis of international criteria, in patients with BrS-ECG and normal echocardiography, looking for a potential overlap between the two pathologies. The secondary objectives were to describe and quantify angiographic structural alterations, hemodynamics, electrophysiology, and genetics in the setting of BrS-ECG. Materials and Methods: Hundred and fourteen consecutive patients matched in age underwent prospectively cardiac catheterization and quantitative biventricular contrast angiography to rule out a structural heart disease. Fifty-one patients with a BrS-ECG (BrS group, 7 F, 44 M, 43 ± 11 y) had a spontaneous or ajmaline-induced BrS coved type ECG. For angiographic comparison, 49 patients with localized ARVD/C but without ST segment elevation in the right precordial leads (14 F, 35 M, 39 ± 13 y) were also studied. They fulfilled international ESC/WHF 2000 criteria and presented angiographic localized forms, mainly confined to hypokinetic anteroapical zone (characterized by trabecular dysarray and hypertrophy), and/or diaphragmatic wall, thus resulting in RV normal volumes and preserved systolic function. These two populations were also compared with 14 control patients (7 F, 7 M, 38 ± 16 y). Among BrS group, we identified three main angiographic phenotypes: BrS group I = patients with normal RV (n = 15, 29%); BrS group II = patients with segmental RV wall motion abnormalities but no structural arguments for ARVD/C (n = 26, 51%); BrS group III = patients with localized abnormalities suggestive of focal ARVD/C (n = 10, 20%). Results: Among BrS group, 34/51 patients (67%) fulfilled BrS HRS/EHRA 2005 criteria. Nineteen (37%) were symptomatic for aborted sudden death, agonal nocturnal respiration or syncope. Ventricular stimulation was positive in 14 patients (28%). Angiography showed RV abnormalities in 36/51 patients (71%) of BrS group (BrS groups II and III). Late potentials were present in 73% (100% sensitivity and NPV for an angiographic ARVD/C, but poor specificity and PPV, both 37%). In BrS group III, 8/10 patients (16% of BrS patients) finally fulfilled international ESC/WHF 2000 ARVD/C criteria and 5/10 (10% of BrS patients) fulfilled BrS diagnostic criteria. An overlap was observed in 4 patients (8% of BrS patients) who fulfilled both ARVD/C and BrS criteria. Among the 45 genotyped patients, only one presented a SCN5A mutation, whereas a TRPM4 mutation was found in another patient. Both belonged to BrS group II. MOG1 gene analysis was negative for all patients, as were PKP2, DSP, DSG2, and DSC2 analyzes performed in BrS group III. Conclusions: Seventy-one percent of patients with a BrS-ECG had abnormal RV wall motion and 16 had structural alterations corresponding to localized (anteroapical and/or diaphragmatic) ARVD/C. Moreover, 8% of BrS-ECG patients fulfilled both BrS and ARVD/C criteria. Our results support the hypothesis of an overlap between BrS and localized forms of ARVD/C. Conversely, genetic screening was poorly contributive for both diseases in the present series.

Brugada electrocardiographic pattern induced by fever

Brugada syndrome is a major cause of sudden death in young adults. Fever has been described to induce a Brugada-type electrocardiogram in asymptomatic patients with a negative family history, to disclose Brugada syndrome and to increase the risk of death and induce T wave alternans in patients with diagnosed Brugada syndrome. Risk stratification is challenging and demands a careful evaluation. Here we present 2 case reports and review the literature.

Abstract 9693: Onset of Lone Atrial Fibrillation Before 40 Years is Associated with a High Prevalence of Mutations in the Cardiac Sodium Channel

Introduction Atrial Fibrillation (AF) is the most common sustained arrhythmia. Studies screening SCN5A, the gene encoding the α-subunit of the cardiac sodium channel, have reported that around 0-2 % of general AF patients have mutations in the gene. Hypothesis We tested the hypothesis that early onset lone AF is associated with a high prevalence of genetic variation in SCN5A and CAV3, both genes encoding important components of the cardiac sodium channel. Methods We sequenced the coding region and splice-site of SCN5A and CAV3 in 192 early onset lone AF patients. Only lone AF patients with onset of disease before the age of 40 years and without traditional risk factors for AF were included; patients with structural heart disease, diabetes or metabolic diseases or other disease were excluded. For electrophysiological patch clamp studies HEK cells were transiently co-transfected with pcDNA3-hSCN5A, and pcDNA3-eGFP as a reporter gene. Results Of 192 probands with early onset lone AF, nine non-synonymous mutations were found in ten probands: eight mutations in SCN5A; T220I, R340Q, T1304M, F1596I, R1626H (novel), D1819N, R1897W (novel), V1951M and one mutation in CAV3 (T78M in two patients). None of the mutations were present in public available databases and only V1951M has previously been reported in conjunction to AF. All other mutations affected evolutionarily conserved residues. All patient caring SCN5A mutations underwent a flecainide test, without inducing any sings of Brugada ECG pattern. SCN5A, T220I, T1304M and CAV3 T78M has been electrophysiologically investigated earlier and the mutations all significantly compromises sodium current. In vitro electrophysiological studies were conducted of the remaining mutations. R340Q, R1626H and R1897W showed loss-of-function while T1304M showed gain-of-function. F1596I did not affect the electrophysiologic function while V1951 showed both loss-of-function and gain of function. Conclusions Ten out of 192 patients with early-onset lone AF had a non-synonymous mutation in SCN5A and CAV3. All ten mutations either had been or were investigated electrophysiologically and of those, seven mutations compromised the sodium current and are therefore suspected to enhance the susceptibility to AF.

Loss-of-Function Sodium Channel Mutations in Infancy

The role of channelopathies in the pathogenesis of sudden cardiac death in patients with structurally normal hearts is a rapidly evolving story.1 Many ion channels are involved, including loss-of-function sodium channelopathies, of which the phenotypic spectrum ranges from lethal arrhythmias to asymptomatic carriers and includes Brugada syndrome (BrS), cardiac conduction disease, sick sinus syndrome, atrial fibrillation, and dilated cardiomyopathy. BrS, characterized by right precordial ST elevation on the ECG, is frequently associated with conduction delay, potentially lethal arrhythmias, and a positive family history of sudden premature death. BrS is estimated to be responsible for ≈4% of all sudden deaths and 20% of sudden deaths in patients with structurally normal hearts. Despite an overall prevalence of ≈5/10 000 individuals,2 BrS is considered extremely rare in the pediatric population. However, children harboring loss-of-function mutations in the gene coding for the sodium channel α-subunit ( SCN5A ) have been reported to present with life-threatening arrhythmias, especially during febrile episodes.3 While SCN5A mutations account for 11% to 28% of BrS probands, mutations of the L-type calcium channel, including the gene coding for the L-type calcium channel β-subunit ( CaCNB2 ), among others, have recently been implicated in ≈13% of patients with BrS-related phenotypes and sudden cardiac death.4 Article see p 14 In this issue of Circulation , Kanter et al5 describe their experience with very young children manifesting ventricular arrhythmias due to previously undetected loss-of-function sodium and/or calcium channelopathies. Twenty of 32 patients <2 years of age with rapid ventricular tachycardia (VT) or ventricular fibrillation (VF), had known structural heart disease, and 9 of the remaining 12 patients had intraventricular conduction delay (IVCD) or Brugada pattern (coved) ECG, of which 4 had associated conditions (myocarditis, Barth syndrome, and drug use). The clinical features and subsequent management and follow-up of the remaining 5 patients …

Brugada Electrocardiographic Pattern in Carbon Monoxide Poisoning

Carbon monoxide (CO) poisoning is the most common type of accidental poisoning in the United States, contributing to an estimated 15,000 emergency department visits and 500 deaths in the United States each year [1]. The signs and symptoms of CO poisoning are diverse, ranging from headache, lethargy, dizziness, nausea and confusion to cardiac and neurological disturbances. Cardiovascular complications of CO poisoning include myocardial ischemia, left ventricular dysfunction, or arrhythmias. We report the first case of Brugada electrocardiographic pattern (BEP) in CO poisoning in the English literature. A 56-year-old hispanic male was found unconscious in his home by his son who called the emergency medical services. Patient regained consciousness while receiving 100% oxygen by means of non rebreather reservoir face mask in the ambulance. Upon arrival to the emergency room, the patient was awake, but complained of mild headache and dizziness. He denied any chest pain, palpitation or shortness of breath. Past medical history was significant for dyslipidemia, being treated with simvastatin. Family history was negative for sudden cardiac death. Vital signs on admission showed a temperature of 100.4 F, heart rate of 110 beats/minute, blood pressure of 129/89 mm Hg, respiratory rate of 24 per minute, with oxygen saturation of 100% on non-rebreather mask delivering 100% oxygen. Arterial blood gas analysis by co-oximetry showed pH 7.48, pCO2 33 mm Hg, pO2 250 mm Hg, HCO3 24.6 mmol/l, and oxygen saturation of 99%. Carboxyhemoglobin (COHb) level on admission was 25.2%. Creatine kinase, creatine kinase-MB isoenzyme, and troponin I was within normal limits. Electrocardiogram (ECG) done in emergency room showed sinus tachycardia at 104 beats per minute, left axis deviation, and ST-segment elevation of 3.5 mm in V1-V2 with a saddleback appearance, characteristic of type 2 BEP (Figure 1 A). Urine toxicology screen was negative for cocaine, amphetamines, opiates and benzodiazepines. Serum anion gap was normal and no osmolal gap was noted. Portable chest radiograph was within normal limits. Transthoracic 2-dimensional echocardiogram (ECHO) showed normal left ventricular systolic function, and no regional wall motion abnormalities. The patient was admitted to telemetry unit and administered 3 cycles of hyperbaric-oxygen therapy (HBOT) within a 24-hour period. Repeat ECG after HBOT showed resolution of the bruCorresponding author: Prof. Wilbert S. Aronow MD, FACC, FAHA Cardiology Division New York Medical College Macy Pavilion, Room 138 Valhalla, NY 10595, USA Phone: (914) 493-5311 Fax: (914) 235-6274 E-mail: wsaronow@aol.com Letter to the Editor

Does a Brugada Pattern ECG Precipitated by Excessive-Dose Flecainide Provide a Diagnosis of a Brugada Syndrome Patient and/or Contraindicate Its Use?

The patient is a 58-year-old white male cardiologist who first came to attention in 2004 at the age of 53 years, with a history of paroxysmal atrial fibrillation (PAF) dating to 1982. The episodes, which were often precipitated by recumbency and alcohol, occurred 2 to 3 times per year and lasted only minutes. His ECG (Figure 1) while in normal sinus rhythm was normal. Figure 1. ECG taken when the patient was not using flecainide. His PAF was not rapid and did not cause hemodynamic or ischemic symptoms. During 2003 to 2004, the PAF increased in frequency to several times per week and lasted longer, for which he began flecainide 50 mg bid with success for 6 months. Thereafter, however, they recurred with a progressive increase in frequency to several times per day, despite increasing the flecainide to 100 mg bid and then 150 mg bid and thereafter while trying sotalol up to 160 mg bid instead. A stress-echo was normal aside from a left atrial diameter of 4.5 cm (an increase from 10 years earlier). There was no family history of any dysrhythmia, syncope, seizure disorder, or sudden death and no other personal medical history of any relevance aside from simvacor-controlled hyperlipidemia (including no personal or family history of syncope or sudden death). His physical examination was entirely normal. All routine laboratory studies were normal, as was his 12-lead ECG and chest radiography. While taking flecainide, his PAF recurred as typical atrial flutter. The QRST pattern on his 12-lead ECG did not change during the flecainide or sotalol administration. Catheter ablation was recommended. While considering ablation and proceeding to schedule it, the patient took a trip out of the country, during which, while on a cruise, a protracted episode recurred. At that time he was again taking flecainide 50 mg bid …

The value of a family history of sudden death in patients with diagnostic type I Brugada ECG pattern

We sought to investigate the value of a family history of sudden death (SD) in Brugada syndrome (BS). Two hundred and eighty consecutive patients (mean age: 41 ± 18 years, 168 males) with diagnostic type I Brugada ECG pattern were included. Sudden death occurred in 69 (43%) of 157 families. One hundred and ten SDs were analysed. During follow-up VF (ventricular fibrillation) or SD-free survival rate was not different between patients with or without a family history of SD of a first-degree relative, between patients with or without a family history of multiple SD of a first-degree relative at any age and between patients with or without a family history of SD in first-degree relatives ≤35 years. One patient had family history of SD of two first-degree relative ≤35 years with arrhythmic event during follow-up. In univariate analysis male gender (P = 0.01), aborted SD (P < 0.001), syncope (P = 0.04), spontaneous type I ECG (P < 0.001), and inducibility during electrophysiological (EP) study (P < 0.001) were associated with worse prognosis. The absence of syncope, aborted SD, spontaneous type I ECG, and inducibility during EP study was associated with a significantly better prognosis (P < 0.001). Family history of SD is not predictive for future arrhythmic events even if considering only SD in first-degree relatives or SD in first-degree relatives at a young age. The absence of syncope, aborted SD, spontaneous type I ECG, and inducibility during EP study is associated with a good five-year prognosis.

A Case of Asymptomatic Brugada Electrocardiographic Pattern Incidentally Unmasked During the Recovery Phase of an Exercise Stress Test

The interest about Brugada syndrome, an inherited channelopathy associated with sudden cardiac death in individuals without structural heart disease, is exponentially increasing lately. Similarly to chameleon, the electrocardiographic (ECG) signal of the disease fluctuates over time, it is often concealed, and may be unmasked under certain conditions. Recently, emergence of the characteristic ST-segment elevation during exercise stress test (EST) has been reported, probably resulting from an alteration of the autonomic tone in the different stages of exercise. We present the case of a 43-year-old, otherwise healthy male with an asymptomatic Brugada ECG pattern incidentally unmasked during the recovery phase of an EST.

Anesthetic management of patients with Brugada syndrome: a case series and literature review

To review the anesthetic management and perioperative outcomes of patients diagnosed with Brugada syndrome (BrS) who were treated at a single centre and to compare those results with a comprehensive review of the existing literature. A retrospective chart review of anesthesia records from patients diagnosed with BrS at the Mayo Clinic was undertaken with the emphasis on administered drugs, ST segment changes, and occurrence of complications, including death, hemodynamic instability, and dysrhythmias. Eight patients were identified who underwent a total of 17 operative procedures from 2000 through 2010. A total of 20 significant ST segment elevations were recorded in four patients, several of which occurred in close temporal relation to anesthetic drug administration. These elevations resolved uneventfully. There were no recorded dysrhythmias, and recovery from anesthesia proceeded uneventfully. A literature review of patients with BrS yielded 52 anesthetics in 43 patients. The only recorded complications included unmasking of a Brugada ECG pattern, one episode of polymorphic ventricular tachycardia, which converted spontaneously to sinus rhythm, and one episode of postoperative ventricular fibrillation in the setting of epidural anesthesia. In this series and in the literature, BrS patients tolerated anesthesia without untoward disease-related complications. Propofol and local anesthetics carry a theoretical risk of arrhythmogenic potential in BrS patients, but clear evidence is lacking. However, awareness of their potential to induce arrhythmias warrants caution, especially with propofol infusions. Factors that might exacerbate ST segment elevations and subsequently lead to dysrhythmias (e.g., hyperthermia, bradycardia, and electrolyte imbalances, such as hyper- and hypokalemia and hypercalcemia) should be avoided or corrected.

Risk stratification in Brugada syndrome

Individuals with type 1 Brugada ECG pattern may suffer from malignant ventricular arrhythmias (Brugada syndrome). Patients with Brugada syndrome and documented cardiac arrest should receive an implantable cardioverter-defibrillator. In the remaining subjects, the best management is controversial. Many data suggest that patients with syncope, particularly if they have a spontaneous type 1 ECG pattern, have a significant risk. In the remaining population of asymptomatic subjects, the risk is lower but not negligible. How to manage these latter cases is an unsolved issue. The usefulness of the electrophysiological study (EPS) in risk stratification, i.e. inducibility of sustained ventricular tachycardia/fibrillation, is controversial. Indeed, some authors strongly support the prognostic value of EPS, while others completely deny its usefulness. We recently published our experience concerning the usefulness of a combined approach that considered both clinical data and EPS results; 320 patients (258 males, mean age 43 years) with type 1 ECG were enrolled. No patient had previous cardiac arrest; 54% of patients had a spontaneous and 46% a drug-induced type 1 ECG. One third had syncope, two thirds were asymptomatic; 245 patients underwent EPS; 110 patients received an implantable defibrillator. Patients were followed up for 40 months. During follow-up, 17 patients had major arrhythmic events (MAE) (14 resuscitated ventricular fibrillations and 3 sudden deaths). Both spontaneous type 1 ECG and syncope significantly increased the risk (8.6% and 10.4% event rates vs 2.8% and 1.3%). MAE occurred in 14% of subjects with positive EPS, in no subjects with negative EPS, and in 5.3% of subjects without EPS. All MAE occurred in subjects who had ≥ 2 risk factors (syncope, family history of sudden death and positive EPS). Among these patients, those with spontaneous type 1 ECG had a 30% event rate. In subjects with drug-induced type 1 MAE were rare. In conclusion, 1) in subjects with the Brugada type 1 ECG neither a single clinical risk factor nor EPS alone are able to identify subjects at the highest risk; 2) a multiparametric approach (including syncope, family history of sudden death and positive EPS) helps to identify populations at the highest risk; 3) subjects at the highest risk are those with a spontaneous type 1 ECG and ≥ 2 risk factors; 4) the remainder is at low risk.