Predicting and Recognizing Drug-Induced Type I Brugada Pattern Using ECG-Based Deep Learning

BACKGROUND

Brugada syndrome (BrS) has been associated with sudden cardiac death in otherwise healthy subjects, and drug-induced BrS accounts for 55% to 70% of all patients with BrS. This study aims to develop a deep convolutional neural network and evaluate its performance in recognizing and predicting BrS diagnosis.

METHODS AND RESULTS

Consecutive patients who underwent ajmaline testing for BrS following a standardized protocol were included. ECG tracings from baseline and during ajmaline were transformed using wavelet analysis and a deep convolutional neural network was separately trained to (1) recognize and (2) predict BrS type I pattern. The resultant networks are referred to as BrS-Net. A total of 1188 patients were included, of which 361 (30.3%) patients developed BrS type I pattern during ajmaline infusion. When trained and evaluated on ECG tracings during ajmaline, BrS-Net recognized a BrS type I pattern with an AUC-ROC of 0.945 (0.921-0.969) and an AUC-PR of 0.892 (0.815-0.939). When trained and evaluated on ECG tracings at baseline, BrS-Net predicted a BrS type I pattern during ajmaline with an AUC-ROC of 0.805 (0.845-0.736) and an AUC-PR of 0.605 (0.460-0.664).

CONCLUSIONS

BrS-Net, a deep convolutional neural network, can identify BrS type I pattern with high performance. BrS-Net can predict from baseline ECG the development of a BrS type I pattern after ajmaline with good performance in an unselected population.

Brugada phenocopy associated with multiple psychotic drugs

Brugada phenocopy (BrP) is a clinical condition characterized by transient ECG changes of Brugada syndrome (BrS), which can be due to various clinical conditions. We describe a case report of BrP due to psychotic drugs.

Assessment of atrial functional remodeling in patients with atrioventricular nodal reentrant tachycardia with and without drug-induced type 1 Brugada pattern: A case-control study

PURPOSE

The time interval between the onset of the P-wave on electrocardiogram (ECG) and peak A' velocity of the lateral left atrial wall assessed by tissue Doppler imaging (PA-TDI interval) determine total atrial conduction time (TACT) which reflects atrial remodeling and arrhythmic substrate. In this retrospective study, we aimed to assess TACT in patients with atrioventricular nodal reentrant tachycardia (AVNRT) with and without drug-induced type 1 Brugada electrocardiogram ECG pattern (DI-Type 1 BrP) and control subjects.

METHODS

Study population consisted of 62 consecutive patients (46 women; mean age 44 ± 12 years) undergoing electrophysiological study and ablation for symptomatic, drug-resistant AVNRT, and 42 age-matched and sex-matched control subjects. All patients and control subjects underwent ajmaline challenge test and tissue Doppler imaging.

RESULTS

A DI-Type 1 BrP was uncovered in 24 of 62 patients with AVNRT (38.7%). PA-TDI interval was similar among AVNRT patients with and without DI-Type 1 BrP (124 ± 12 ms vs 119 ± 14 ms, respectively, P = .32), but significantly longer in patients with AVNRT with as well as without DI-Type 1 BrP than in control subjects (124 ± 12 ms and 119 ± 14 ms vs 105 ± 11 ms, respectively, P < .001).

CONCLUSION

The TACT assessed by PA-TDI interval is longer in patients with AVNRT with and without DI-Type 1 BrP than in age-matched and sex-matched healthy control subjects.

Lacosamide induced Brugada I morphology in the setting of septicemia: A case report

INTRODUCTION

Brugada syndrome may be unmasked by non-antiarrhythmic pharmaceuticals or drugs. Lacosamide is an antiepileptic agent with a novel mechanism of sodium channel inhibition and has the potential to cause cardiac sodium channel blockade.

PATIENT CONCERNS

In this report, we describe the case of patient with a history of a seizure disorder who presented with Brugada I electrocardiogram morphology in the setting of septicemia.

DIAGNOSIS

Brugada I electrocardiogram morphology was unmasked by lacosamide antiepileptic monotherapy.

INTERVENTIONS

Lacosamide therapy was discontinued.

OUTCOMES

Normalization of the electrocardiogram and resolution of Brugada morphology occurred on hospital day 1.

CONCLUSION

Caution should be exercised in the use of lacosamide in those at risk for conduction delay, or in combination therapy with medications that impair renal clearance, metabolism of lacosamide, or that display inherent sodium channel blocking properties.

Electrocardiographic findings of methanol toxicity: a cross-sectional study of 356 cases in Iran

BACKGROUND

Methanol is widely used in industry; however, methanol poisoning is not common. In this regard, a number of outbreaks have been recently reported due to inappropriate processing of alcoholic beverages. Shiraz, a city located in the southern part of Iran, faced one of such outbreaks in 2020 during COVID-19 pandemic. There is no sufficient literature on the electrocardiographic findings in methanol toxicity. This study aimed to address this gap in the literature.

METHOD

A total of 356 cases with methanol toxicity referred to Shiraz University of Medical Science Tertiary Hospitals (Faghihi and Namazi) in March and April, 2020. The clinical findings of blindness and impaired level of consciousness, lab data such as arterial blood gas, electrolytes, and creatinine, and the most common findings from ECGs were collected.

RESULTS

The most common ECG findings were J point elevation (68.8%), presence of U wave (59.2%), QTc prolongation (53.2% in males and 28.6% in females), and fragmented QRS (33.7%). An outstanding finding in this study was the presence of myocardial infarction in 5.3% of the cases. This finding, to the best of our knowledge, has only been reported in a few case reports. Brugada pattern (8.1%) and Osborn wave (3.7%) were the other interesting findings. In multivariate analysis, when confounding factors were adjusted, myocardial infarction, atrioventricular conduction disturbances, sinus tachycardia, and the prolonged QTC > 500 msecond were four independent factors correlated with methanol toxicity severity measured with arterial blood PH on arterial blood gas measurements, with odds ratios of 12.82, 4.46, 2.32 and 3.15 (P < 0.05 for all), respectively.

CONCLUSION

Electrocardiographic variations during methanol intoxication are remarkable and well-correlated with poisoning severity. Myocardial infarction was an egregious and yet a common concerning finding in this sample, which need to be ruled out in methanol toxicity.

Brugada Syndrome Induced by an Interscalene Block: A Case Report

CASE

A 57-year-old woman with no noteworthy medical or surgical history underwent an interscalene block with bupivacaine in preparation for an arthroscopic rotator cuff repair. Following administration of the bupivacaine, the patient sustained a ventricular fibrillation arrest. After successful cardiopulmonary resuscitation, she was diagnosed with Brugada syndrome. An implantable cardioverter-defibrillator was placed, and the rotator cuff repair was performed 1 month later.

CONCLUSION

Brugada syndrome is an abnormality of the cardiac conduction system that leads to cardiac arrhythmias. Several anesthetic agents trigger Brugada-like electrocardiographic abnormalities. To our knowledge, this is the first report of an interscalene block inducing Brugada syndrome.

A Carbamazepine-induced Brugada-type Electrocardiographic Pattern in a Patient with Schizophrenia

We report the case of a 61-year-old man with schizophrenia who was treated with carbamazepine, in whom electrocardiography showed transient Brugada-type ST elevation. He had been hospitalized our hospital's Department of Psychiatry and had been diagnosed with pneumonia. On the following day, electrocardiography showed coved-type ST elevation in the right precordial leads and a blood examination revealed that the patient's carbamazepine concentration was at the upper limit of the standard range, as well as hypothyroidism. The patient's electrocardiogram normalized after the withdrawal of carbamazepine. We demonstrated that the patient's carbamazepine concentration-and not hypothyroidism-was associated with the serial electrocardiographic changes by monitoring the patient's blood concentration of carbamazepine and his thyroid function.

Diagnosis of Brugada's syndrome after subarachnoid injection of prilocaine

Brugada syndrome is an autosomal dominant genetic disease affecting sodium ion channels. It is characterised by right bundle branch block and ST elevation in the right precordial leads, and with no structural cardiac abnormalities. It is associated with sudden death. This disease may be unmasked by certain drugs and sudden changes in autonomic tone. Local anaesthetics may increase ECG changes due to a blockade of the sodium channels, mainly depending on the dose and the type of anaesthetic. Thus, there have been reported electrocardiographic changes consistent with Brugada syndrome, triggered after epidural or paravertebral infusion of bupivacaine and ropivacaine. The case is described of a 66 years old man, scheduled for inguinal herniorrhaphy as an outpatient. He had no history of syncope or arrhythmias. After spinal anaesthesia with 40mg of prilocaine the ECG showed ST elevation>2mm, and right bundle branch block in V1-V3.

A Novel SCN5A Mutation Associated with Drug Induced Brugada Type ECG

Background

Class IC antiarrhythmic agents may induce acquired forms of Brugada Syndrome. We have identified a novel mutation in SCN5A, the gene that encodes the α-subunit of the human cardiac sodium channel (hNa_v1.5), in a patient who exhibited Brugada- type ECG changes during pharmacotherapy of atrial arrhythmias.

Objective

To assess whether the novel mutation p.V1328M can cause drug induced Brugada Syndrome.

Methods

Administration of pilsicainide, a class IC antiarrhythmic agent, caused Brugada- type ST elevation in a 66-year-old Japanese male who presented with paroxysmal atrial fibrillation (PAF), type I atrial flutter and inducible ventricular fibrillation (VF) during electrophysiological study. Genetic screening using direct sequencing identified a novel SCN5A variant, p.V1328M. Electrophysiological parameters of WT and p.V1328M and their effects on drug pharmacokinetics were studied using the patch-clamp method.

Results

Whole-cell sodium current densities were similar for WT and p.V1328M channels. While p.V1328M mutation did not affect the voltage-dependence of the activation kinetics, it caused a positive shift of voltage-dependent steady-state inactivation by 7 mV. The tonic block in the presence of pilsicainide was similar in WT and p.V1328M, when sodium currents were induced by a low frequency pulse protocol (q15s). On the contrary, p.V1328M mutation enhanced pilsicainide induced use-dependent block at 2 Hz. (Ki: WT, 35.8 μM; V1328M, 19.3 μM).

Conclusion

Our study suggests that a subclinical SCN5A mutation, p.V1328M, might predispose individuals harboring it to drug-induced Brugada Syndrome.

[ETACISIN-INDUCED BRUGADA SYNDROME IN A PATIENT WITH LONG-STANDING SUPRAVENTRICULAR EXTRASYSTOLE]

Brugada syndrome is a commonest cause of malignant disorders of cardiac rhythm associated with sudden death. It is diagnosed based on characteristic ECG signs and ventricular arrhythmia. This paper reports a 49 year-old patient with long-standing latent BS manifest as supraventricular and transient blockade of the right branch of the His bundle. The ECG pattern of BS became apparent in association with a 7 day treatment with class IC antiarrhythmic agent etacisin. Diagnostic difficulties account for the fact that the disease was initially described as myocardial infarction. Diagnosis of BS was confirmed by an electrophysiological study in which stable ventricular tachycardia and fibrillation were induced by etacisin. A cardioverter defibrillator was implanted to the patient.

Transcranial magnetic stimulation as an antidepressant alternative in a patient with Brugada syndrome and recurrent syncope

Brugada syndrome (BrS) is a common occult cause of sudden cardiac arrest in otherwise healthy-appearing adults. The pathognomonic electrocardiographic pattern may be unmasked only by certain medications, many of which are unknown. We report a case of a depressed but otherwise healthy man with an asymptomatic right bundle branch block on electrocardiography who experienced antidepressant-induced BrS and ultimately recovered with transcranial magnetic stimulation (TMS). After an initial trial of nortriptyline, the patient's depressive symptoms improved; however, he experienced a syncopal event and was subsequently diagnosed as having BrS. Cross titration to bupropion, which had not previously been known to exacerbate BrS, was followed by another cardiac event. As a result, the patient was referred for TMS as a substitute for pharmacotherapy. After 31 TMS sessions over 8 weeks, the patient demonstrated significant improvement by subjective report and objective reduction in his Patient Health Questionnaire-9 scores from 10 (moderate) to 1 (minimal). Transcranial magnetic stimulation is a Food and Drug Administration-approved nonpharmacologic treatment for depression. Given the potential lethality of BrS with known and unknown psychopharmacologic agents, providers should consider TMS as first-line therapy in this patient population. Bupropion should be added to the list of agents known to exacerbate this disease.

Ventricular fibrillation induction and diffuse abnormal ST-segment response to ajmaline in a patient with apparent pre-existing dynamic right bundle branch block

OBJECTIVE

ST-segment elevation in the right precordial electrocardiography (ECG) leads in Brugada syndrome (BS) can be unmasked by class I anti-arrhythmic drugs (sodium channel blockers) administration. It is still debated whether this ECG pattern is better explained by abnormal repolarization or ventricular conduction and depolarization. Conduction diseases can conceal type 1 BS-like ECG in standard V1-V3 leads. ECG alterations were found also in alternative leads. The role of electrophysiology study (EPS) in sudden cardiac death risk stratification remains controversial, and could depend on the phenotypic expression of the cardiac sodium channels disease.

CASE REPORT

We describe unmasked diffuse J-point and ST-segment anomalies in peripheral and precordial ECG leads and ventricular fibrillation (VF) induction by EPS after ajmaline administration in a patient with pre-existing atypical right bundle branch block (RBBB) concealing subtle anomalies in standard V1-V3 leads. RBBB was influenced by the underlying BS-like ECG associating repolarization anomaly and pre-existing conduction disease. EPS induced VF when RBBB was associated with BS-like ECG, and failed to induce VF when RBBB was present alone.

CONCLUSIONS

BS phenotype heterogeneity requires further studies to improve the knowledge of its pathophysiological mechanisms associated with conduction diseases in order to better identify an individual therapy and prognostic stratification.

Propofol-induced coved-type electrocardiogram during catheter ablation of paroxysmal atrial fibrillation. A case of Brugada syndrome?

We report a case of a young man with paroxysmal atrial fibrillation, in whom a characteristic coved-type Brugada pattern developed during catheter ablation performed under sedation with propofol. After immediate discontinuation of the propofol infusion, coved-type ST-segment elevation gradually resolved and no ventricular arrhythmias occurred. An ajmaline challenge failed to unmask a coved-type electrocardiogram and genetic testing was negative for ion channel mutations related to Brugada syndrome.

[Case of ventricular fibrillation in patients with brugada type electrocardiogram during surgery]

We described a case of ventricular fibrillation in patients with Brugada type electrocardiogram (ECG) during surgery. A 63-year-old man underwent lung lobectomy under combined general and epidural anesthesia. His preoperative ECG showed Brugada type, but he was asymptomatic and did not have a family history of sudden death. Anesthesia was induced using propofol, vecuronium and fentanyl, and maintained using propofol and lidocaine via epidural catheter. One hour into operation, ventricular fibrillation developed. After cardiac compression in a few seconds, sinus rhythm was restored and blood pressure was elevated. When the wound was sutured, ventricular fibrillation occurred again. Defibrillation was attempted immediately and sinus rhythm was restored. We diagnosed coronary spastic angina after acetylcholine challenge test. Previous report describes that the incidence of vasospasm in Brugada type ECG cases is relatively higher than those with the normal ECG. In addition, ventricular fibrillation might be induced by local anesthetics because these agents were administrated 10 minutes before the few events and balance of autonomic nervous system was changed. We conclude that strict monitoring and immediate treatment for ventricular fibrillation are important for anesthetic management in asymptomatic patient with Brugada type ECG.

Brugada like pattern in ECG with drug overdose

Tricyclic antidepressants (TCAs) may have dangerous cardiac effects in overdose. ECG is useful as both a screening tool for tricyclic antidepressant exposure and as a prognostic indicator. TCA overdose may produce various ECG changes. We report a case of Dothiepin overdose resulting in Brugada like pattern including RBBB which resolved spontaneously.

Propofol infusion syndrome and Brugada syndrome electrocardiographic phenocopy

This anesthetic drug may cause a rare condition named propofol infusion syndrome, characterized by unexplained lactic acidosis, lipemia, rhabdomyolysis, cardiovascular collapse and Brugada-like electrocardiographic pattern or Brugada electrocardiographic phenocopy changes following high-dose propofol infusion over prolonged periods of time. Several articles have contributed to our understanding of the cause of the syndrome, and the growing number of case reports has made it possible to identify several risk factors. Uncertainty remains as to whether a genetic susceptibility exists. The favorable recovery profile associated with propofol offers advantages over traditional anesthetics in clinical situations in which rapid recovery is important. Propofol is a safe anesthetic agent, but propofol infusion syndrome is a rare lethal complication.

Brugada syndrome case: difficult differentiation between a concealed form and tricyclic antidepressant-induced Brugada sign

We describe a case of Brugada syndrome, in which recurrent syncope with convulsive seizures was induced after antidepressant treatment. The patient had been treated with five kinds of psychotropic drugs. The twelve-lead ECG after the syncope exhibited an RSR'-pattern in the precordial leads, however, a coved type ST-segment elevation was induced by a pilsicainide test. Although ventricular fibrillation was not induced in the electrophysiologic study, an ICD implantation was considered as the recommended therapy since Brugada syndrome unmasked by antidepressants could not be ruled out. The possible contribution of antidepressants to Brugada type ST-segment changes is discussed.

Criteria for arrhythmogenicity in genetically-modified Langendorff-perfused murine hearts modelling the congenital long QT syndrome type 3 and the Brugada syndrome

The experiments investigated the applicability of two established criteria for arrhythmogenicity in Scn5a+/Delta and Scn5a+/- murine hearts modelling the congenital long QT syndrome type 3 (LQT3) and the Brugada syndrome (BrS). Monophasic action potentials (APs) recorded during extrasystolic stimulation procedures from Langendorff-perfused control hearts and hearts treated with flecainide (1 microM) or quinidine (1 or 10 microM) demonstrated that both agents were pro-arrhythmic in wild-type (WT) hearts, quinidine was pro-arrhythmic in Scn5a+/Delta hearts, and that flecainide was pro-arrhythmic whereas quinidine was anti-arrhythmic in Scn5a+/- hearts, confirming clinical findings. Statistical analysis confirmed a quadratic relationship between epicardial and endocardial AP durations (APDs) in WT control hearts. However, comparisons between plots of epicardial against endocardial APDs and this reference curve failed to correlate with arrhythmogenicity. Restitution curves, relating APD to diastolic interval (DI), were then constructed for the first time in a murine system and mono-exponential growth functions fitted to these curves. Significant (P<0.05) alterations in the DI at which slopes equalled unity, an established indicator of arrhythmogenicity, now successfully predicted the presence or absence of arrhythmogenicity in all cases. We thus associate changes in the slopes of restitution curves with arrhythmogenicity in models of LQT3 and BrS.

Drug-induced spatial dispersion of repolarization

Spatial dispersion of repolarization in the form of transmural, trans-septal and apico-basal dispersion of repolarization creates voltage gradients that inscribe the J wave and T wave of the ECG. Amplification of this spatial dispersion of repolarization (SDR) underlies the development of life-threatening ventricular arrhythmias associated with inherited or acquired ion channelopathies giving rise to the long QT, short QT and Brugada syndromes (BrS). This review focuses on the role of spatial dispersion of repolarization in drug-induced arrhythmogenesis associated with the long QT and BrS. In the long QT syndrome, drug-induced amplification of SDR is often secondary to preferential prolongation of the action potential duration (APD) of M cells, whereas in the BrS, it is thought to be due to selective abbreviation of the APD of right ventricular epicardium. Among the challenges ahead is the identification of a means to quantitate SDR non-invasively. This review also discusses the value of the interval between the peak and end of the T wave (T(peak)-T(end), T(p)-T(e)) as an index of SDR and transmural dispersion of repolarization, in particular.

Brugada type electrocardiographic changes induced by concomitant use of lithium and propafenone in patient with Wolff-Parkinson-White syndrome

We report a case of ST elevation in right precordial leads compatible with type 1 Brugada syndrome following administration of propafenone in a patient with Wolff-Parkinson-White syndrome who was receiving lithium at concentrations within therapeutic levels. The mechanism of the electrocardiogram changes was considered to be caused by the two drugs synergistic sodium channel blocking effects.

Incidence of Brugada electrocardiographic pattern and outcomes of these patients after intentional tricyclic antidepressant ingestion

Brugada syndrome is a genetic dysfunction of the myocardial sodium channel that leads to ventricular dysrhythmias. The electrocardiographic (ECG) pattern of Brugada syndrome is occasionally seen after tricyclic antidepressant (TCA) ingestion; however, the outcome and complication risk for these patients is not clear. The objective of our study was to describe the incidence of Brugada ECG pattern (BEP) and serious complications of these patients in a large case series of intentional TCA ingestions. We also compared the proportion of complications of patients with BEP versus those without BEP. We evaluated 402 TCA ingestions, of which 9 (2.3%) were associated with the development of BEP. We compared the adverse outcomes of all TCA ingestions versus TCA ingestions with BEP. A increase in the adverse outcomes in the BEP group was found: seizures (relative risk [RR] 4; 95% confidence interval [CI] 1.5 to 10.8), widened QRS (RR 4.8; 95% CI 1.8 to 12.9), and hypotension (RR 3.9; 95% CI 2.1 to 7.4). To reduce confounding ingestants, we also compared all patients with an isolated TCA ingestion versus those with BEP. A significant increase in adverse outcomes was again found with the BEP group: seizures (RR 3; 95% CI 1.1 to 8.6), widened QRS (RR 4.8; 95% CI 1.5 to 15.1), and hypotension (RR 3.4; 95% CI 1.9 to 22.3). No deaths or dysrhythmias were found in the BEP group. In conclusion, BEP after TCA ingestion is rare, and death or dysrhythmias did not occur. However, patients with BEP are likely at increased risk for TCA-induced complications.

Amitriptyline-induced Brugada pattern fails to respond to sodium bicarbonate

This report describes a Brugada electrocardiographic pattern after tricyclic antidepressant intoxication that fails to resolve following sodium bicarbonate treatment. A 50-year-old male ingested 13.6 grams of amitriptyline and presented in cardiopulmonary arrest. After initial resuscitation, the patient developed a Brugada electrocardiographic pattern. The pattern persisted despite intravenous administration of 700 mEq of sodium bicarbonate. Five hours after the last dose of sodium bicarbonate and 18 hours after initial presentation, the Brugada pattern resolved. No co-ingestants were ingested and an ischemic pattern was not seen on electrocardiogram. The serum amitriptyline level was >1000 ng/ml. Response of the tricyclic-induced Brugada pattern to sodium bicarbonate has not been previously reported.

[Brugada syndrome and other cardiovascular abnormalities related to tricyclic antidepressants ans related drugs intoxication]

The aim of this paper is to report major cardiovascular complications related to intoxication due to tricyclic antidepressants (TCA) and related drugs, especially the stabilizing membrane effect (SME) and Brugada syndrome, and identify risk factors related to cardiac toxicity.

POPULATION AND METHODS

A retrospective study (35 months), including all adult patients admitted for an isolated intoxication by a TCA or a related drug. The statistical analysis of clinical signs and history as well as ECG abnormalities included parameters recorded in emergency rooms.

RESULTS

65 patients without underlying cardiovascular history were retrieved (mean age 30 + 12 years). The intoxication was intentional in all cases, and the mean estimated taken dosage (ETD) was at 749 + 436 mg. Amitriptyline was the most common drug (66%) followed by clomipramine (29%). The cardiovascular examination noted a tachycardia in 63% of cases (mean HR - 108 + 13 bpm), followed by hypotension (SBP = 80 + 40 mmHg) in 11% of cases. The ECG showed a sinus tachycardia (63%), a PR prolongation (>200 ms) in 28% of cases, a MSE (15.4%) and a type-I aspect of Brugada syndrome (15.4%). The analysis of influence of ETD on HR showed a linear relationship, with the equation HR = 82.276 + 0.039 EDT (mg) (R2=0.138, p=0.001). Analyzing the influence of type of drug on ECG abnormalities revealed a more tachycardia effect of amitryptiline vs. clomipramine (p=0.047).

CONCLUSION

Tachycardia is a frequent sign of intoxication, which can be expressed by a linear function depending on ETD. The MSE is more frequently noted with amitriptyline. The clinical aspect of type-I Brugada syndrome is as frequent as the MSE but does not seem prognostic. It is unclear whether it is related to an isolated electrical aspect or it hides a genetic mutation.

Extracorporeal life support in a case of acute carbamazepine poisoning with life-threatening refractory myocardial failure

OBJECTIVE

To report the efficacy of extracorporeal life support (ECLS) in acute carbamazepine poisoning with sustained refractory myocardial failure and a high degree of conductance disturbances.

DESIGN AND SETTING

Case report from the toxicological and medical intensive care unit in a university hospital.

PATIENT

A 26-year-old man with severe myocardial failure unresponsive to 1.7 microg kg(-1) min(-1) epinephrine and 1.9 microg kg(-1) min(-1) norepinephrine (SvO2, 17.8% and cardiac index, 0.8 l min(-1) m(-2)) following a suicidal ingestion of 32 g slow-release carbamazepine.

INTERVENTIONS

ECLS (Jostra-Maquet centrifugal pump (Rotaflow) connected to a hollow-fiber membrane oxygenator).

MEASUREMENTS AND RESULTS

ECLS device allowed inotropic drug weaning while maintaining end-organ function and supported the patient until myocardial recovery. The plasma carbamazepine level was 224 micromol/l on admission and peaked at 338 micromol/l 101 h after admission with a prolonged gastrointestinal absorption phase despite multiple doses of activated charcoal. The patient survived and was successfully explanted on day 6. An extensive and regressive thrombosis of the inferior vena cava was noted. Cardiac function totally recovered and at 2-year follow-up. There were no significant sequelae.

CONCLUSIONS

We report a case of life-threatening myocardial failure with conductance disturbances secondary to an acute carbamazepine poisoning, demonstrating the efficacy of ECLS to assist recovery.

Brugada electrocardiographic pattern elicited by cyclic antidepressants overdose

OBJECTIVE

The Brugada syndrome is a clinical and electrocardiographic familial entity, which may lead to sudden cardiac death. A Brugada pattern ECG may occasionally be caused by conditions such as an overdose of tricyclic antidepressants (TCA). Toxicity of TCA frequently results in the need for critical care support. We retrospectively studied characteristics and electrocardiographic indicators of toxicity of all TCA poisoned patients.

SETTING

All patients admitted from 1/1/2000 to 1/11/2004 to our ICU after an act of deliberate self-poisoning were included. The ECG's were analysed retrospectively by a cardiologist. Patients with an overdose of TCA were divided in three groups; I. without ECG abnormalities, II. Presence of ECG abnormalities but without Brugada signs, III patients with a Brugada pattern ECG.

RESULTS

134 patients were admitted. In 35 patients a TCA was the main toxic substance. In 12 (34%) TCA patients no ECG abnormalities were found. An increase in QRS duration (>100 ms) was seen in 13 (37%) cases. Six (17%) of them demonstrated a Brugada like pattern. The ECG abnormalities resolved quickly after administration of sodium bicarbonate. Length of stay did not differ between groups. APACHE II and the amount of sodium bicarbonate administered were the highest in the Brugada pattern group. Two patients died.

CONCLUSIONS

in TCA poisoning the Brugada pattern ECG is a particular manifestation of the frequently occurring intraventricular conduction disturbances. In intoxicated patients in whom the substance is unknown early recognition of the conduction disturbances is important for suspecting a poisoning with TCA.

[A case of Brugada syndrome with convulsive seizure during antidepressant administration: relation of antidepressant agents and arrhythmia leading to sudden death]

Brugada syndrome is an arrhythmogenetic disease characterized by electrocardiographic ST segment elevation in right precordial leads, which is called "coved type", and an increased risk of sudden death as the result of ventricular fibrillation. We presented a case of Brugada syndrome with a convulsive seizure, during administration of a tricyclic antidepressant for the treatment of a depressive state. A 43-year-old man with bipolar II disorder and obsessive-compulsive disorder was admitted to our hospital for the treatment of a depressive state. There was no medical history of heart failure. Nortriptyline was effective for his depressive as well as for obsessive symptoms. During the treatment, however, he presented a convulsive syncope. Electrocardiography (ECG) showed "coved type" ST segment elevation, and the patient consulted a cardiologist. Electrophysiological study revealed Brugada syndrome, and an implantable cardioverter defibrillator was placed. An overdose of antidepressants has been reported to produce a Brugada-type ECG because of its Na channel antagonism. However, in the present case, the abnormal ECG findings occurred following a usual dosage of nortriptyline. Thus, it is suggested that Brugada syndrome is related to a susceptibility to antidepressants in the present case. Every psychiatrist managing antidepressant therapy should be aware of Brugada syndrome and this ECG pattern, which may be a marker of sudden death.