Cardiovascular

Brugada syndrome: ECG recognition and risk stratification

Clinical Overview and When to Suspect Brugada Syndrome

— Autosomal dominant with incomplete penetrance; SCN5A loss-of-function mutation in ~20–30% of probands (encodes cardiac Naᵥ1.5).

— Male predominance ~8:1 (testosterone-mediated transient outward current Iₜₒ).

— Higher prevalence in Southeast Asian populations; called "SUNDS" (sudden unexplained nocturnal death syndrome) in Thailand/Philippines.

— Mean age at SCD ~40 years; events often at rest, during sleep, or with fever.

— Young or middle-aged patient (especially male) with syncope at rest, nocturnal agonal respirations, or aborted SCD.

— Family history of SCD <45 years, unexplained drowning, or SIDS.

— Fever-triggered syncope or VF (febrile illness unmasks the phenotype).

— Resuscitated cardiac arrest with structurally normal heart on echo/coronary angiography.

— Incidentally noted coved ST elevation in V1–V2 on routine or pre-op ECG.

— Reduced inward Na⁺ current and accentuated transmural voltage gradient in RV outflow tract epicardium → phase 2 reentry → polymorphic VT/VF.

— Conditions that worsen the substrate: fever, vagal tone (sleep, large meals, alcohol), bradycardia, hypokalemia, cocaine, tricyclics, Na-channel blockers.

Board pearl: A young man with nocturnal seizure-like activity, normal echo, normal troponin, and coved V1–V2 ST elevation is Brugada until proven otherwise — not "atypical epilepsy." Order a focused family history of SCD and review the 12-lead with high right precordial leads.

Definition: Brugada syndrome (BrS) is an inherited sodium channelopathy producing characteristic right precordial ST elevation and predisposing to polymorphic VT/VF and sudden cardiac death (SCD) in a structurally normal heart.

Genetics and epidemiology:

When to suspect on Step 3:

Pathophysiology pearls:

Presentation Patterns and Key History

— Aborted SCD / VF arrest in a previously healthy adult — diagnostic in ~17–42% of probands.

— Syncope at rest, during sleep, or after a heavy meal/alcohol; abrupt, no prodrome, rapid recovery.

— Nocturnal agonal respirations, witnessed gasping, or "seizure" episodes that are actually polymorphic VT with secondary anoxic convulsion.

— Palpitations from atrial fibrillation (10–25% — AF is the most common SVT in BrS).

— Asymptomatic ECG finding on pre-employment, pre-operative, or family screening ECG.

— Fever of any cause (viral URI, post-vaccination) — unmasks type 1 pattern; pediatric arrests are often febrile.

— Drugs: class IA (procainamide, ajmaline) and IC (flecainide, propafenone) antiarrhythmics, tricyclics, lithium, cocaine, cannabis, propofol (propofol infusion syndrome mimics), bupivacaine.

— Vagal states: sleep, postprandial, athletic training, micturition.

— Electrolytes: hypokalemia, hypercalcemia; large carbohydrate meals ("full-stomach" trigger).

— Alcohol binges.

— SCD <45 years, unexplained drowning, single-car MVA, SIDS.

— Pacemakers/ICDs in young relatives, known SCN5A mutation, "arrhythmia" deaths.

— Vasovagal has prodrome (nausea, diaphoresis, tunnel vision), upright trigger.

— BrS syncope is abrupt, often supine/nocturnal, no prodrome, may have post-event incontinence/myoclonus mimicking seizure.

Key distinction: Syncope during exertion suggests HCM, CPVT, anomalous coronary, or LQT1 — not Brugada. Brugada syncope is the syncope of rest and sleep. Always ask: "What were you doing right before you passed out?" — the answer reframes the entire workup.

Classic presentations:

Trigger-focused history (high yield):

Family history checklist:

Differentiating from vasovagal syncope:

Physical Exam Findings and Hemodynamic Assessment

— Temperature — even low-grade fever (>37.5°C) can unmask type 1 pattern and precipitate VF; check at every visit.

— Heart rate — bradycardia worsens phenotype; sinus rhythm typical.

— BP — usually normal; orthostatics to rule out vasovagal/orthostatic syncope.

— No murmur, no S3/S4, no displaced PMI — if present, reconsider HCM, valvular disease, or cardiomyopathy.

— A loud P2 or RV heave should prompt evaluation for pulmonary embolism (can cause V1–V2 ST changes mimicking BrS).

— Pectus excavatum or unusual chest wall: can shift ECG leads and create pseudo-Brugada patterns.

— Tongue lateral bite, prolonged postictal confusion → favors true seizure.

— Rapid return to baseline, no postictal state → favors arrhythmic syncope (Brugada, LQTS).

— Polymorphic VT/VF presents as pulseless arrest; if sustained, ACLS with defibrillation is the only effective intervention.

— Hemodynamically tolerated polymorphic VT is rare; treat as unstable.

— Cooling blankets/antipyretics if febrile.

— Review med list for offending agents (see BrugadaDrugs.org).

— Check K⁺, Mg²⁺, glucose.

CCS pearl: In a CCS case of resuscitated VF with suspected Brugada, your early orders should include acetaminophen for any fever, telemetry, electrolyte panel with magnesium, echocardiogram (to exclude structural disease), and a high-lead ECG (V1–V2 at 2nd–3rd intercostal space) — these four moves drive the next 24 hours.

General principle: Brugada syndrome is a channelopathy in a structurally normal heart — the resting physical exam is almost always normal between events. The exam's job on Step 3 is to exclude mimickers, not confirm BrS.

Vital signs to capture:

Cardiac exam:

Neurologic exam after a syncopal/seizure-like event:

Hemodynamic assessment during an acute event:

Look for reversible contributors at bedside:

Diagnostic Workup — ECG, Initial Labs, Imaging

— Type 1 ("coved"): ≥2 mm J-point elevation in ≥1 right precordial lead (V1 and/or V2), with a downsloping coved ST segment descending into a negative T wave. No isoelectric separation.

— Type 2 ("saddleback"): ≥2 mm J-point elevation, saddleback ST with terminal positive or biphasic T wave — suggestive, not diagnostic; needs provocation.

— Type 3: <2 mm — essentially abandoned in current criteria.

— Move V1 and V2 up to the 2nd or 3rd intercostal space. This unmasks type 1 pattern in patients whose RVOT sits higher than standard lead position. Always do this when BrS is suspected and standard ECG is non-diagnostic.

— First-degree AV block, RBBB-like morphology, prolonged PR, fragmented QRS, early repolarization in inferolateral leads (worse prognosis).

— Atrial fibrillation in a young patient with V1–V2 ST elevation.

— Troponin (rule out STEMI/RV infarct).

— BMP with K⁺, Ca²⁺, Mg²⁺; hyperkalemia and hypothermia mimic the pattern.

— CBC, blood cultures if febrile.

— Toxicology — cocaine, TCAs.

— TSH, glucose.

— Transthoracic echocardiogram — must be normal; excludes ARVC, HCM, RV dysfunction.

— Cardiac MRI if echo equivocal or ARVC suspected (fatty infiltration, RV aneurysms absent in BrS).

— Coronary evaluation (CTA or angiography) if ischemia in differential.

Board pearl: A "saddleback" V1–V2 (type 2) pattern is not diagnostic — never label a patient as Brugada on a type 2 ECG alone. Confirm with high leads or sodium-channel blocker challenge before any management decision.

The 12-lead ECG is the diagnostic centerpiece. Three patterns historically described; only Type 1 is diagnostic:

High right precordial leads (key Step 3 maneuver):

Other ECG clues:

Initial labs (to find triggers and exclude mimics):

Imaging:

Diagnostic Workup — Advanced and Confirmatory Studies

— Used when clinical suspicion is high but baseline ECG shows type 2/3 or is non-diagnostic.

— Agents: ajmaline (preferred in Europe, most sensitive), flecainide, procainamide (US standard), pilsicainide.

— Endpoint: conversion to type 1 pattern = positive test.

— Performed in monitored setting with defibrillator, ACLS, and IV access; stop for QRS widening >30%, ventricular ectopy, type 1 emergence, or hypotension.

— Contraindicated if baseline type 1 already present (no added value, only risk).

— Targeted SCN5A sequencing for probands with definite type 1 BrS; positive in ~20–30%.

— Cascade screening of first-degree relatives once a pathogenic variant is identified.

— Negative genetic test does not exclude BrS; phenotype trumps genotype.

— Role debated; inducibility of sustained VT/VF with ≤2 extrastimuli carries modest prognostic weight (PRELUDE, FINGER registries).

— Useful in asymptomatic type 1 patients to refine ICD decision — particularly with spontaneous (not just drug-induced) type 1.

— Class IIb in current guidelines; do not over-rely on it.

— 48-hour Holter or extended event monitor to capture transient type 1 patterns, nocturnal arrhythmias, AF burden.

— Implantable loop recorder for recurrent unexplained syncope with non-diagnostic workup.

— Shanghai Score and Sieira score integrate ECG, symptoms, family history, EPS, and genetics — useful but not a substitute for clinical judgment.

Step 3 management: Order procainamide challenge for a patient with syncope + type 2 V1–V2 pattern + family history of SCD — converting to type 1 confirms diagnosis and changes management to ICD consideration. Do the test in an EP lab with crash cart and informed consent documenting VF risk.

Sodium channel blocker (drug) provocation challenge:

Genetic testing:

Electrophysiology study (EPS) — programmed ventricular stimulation (PVS):

Ambulatory monitoring:

Risk scores:

Risk Stratification and Management Logic

— High risk: survivors of cardiac arrest or documented sustained VT/VF → secondary prevention ICD, Class I.

— Intermediate risk: spontaneous type 1 ECG + syncope of presumed arrhythmic origin → ICD, Class IIa.

— Low risk: asymptomatic patients, especially with only drug-induced type 1 → observation, trigger avoidance; no ICD.

— Spontaneous (not drug-induced) type 1 ECG.

— Male sex.

— Family history of SCD <45 years (modest weight).

— Fragmented QRS, early repolarization in inferolateral leads, first-degree AV block.

— Atrial fibrillation in young patient.

— Inducible VF at EPS with ≤2 extrastimuli (selected cases).

— SCN5A mutation associated with severe phenotype.

— Family history alone without personal symptoms or spontaneous type 1.

— Drug-induced type 1 only, asymptomatic.

— Isolated genetic mutation without phenotype.

1. Confirm diagnosis with type 1 pattern (spontaneous or provoked).

2. Stratify based on symptoms and ECG type.

3. Universal measures for all BrS patients (even low risk):

— Aggressive fever management with acetaminophen at ≥38°C; seek care for persistent fever.

— Avoid BrS-aggravating drugs (see BrugadaDrugs.org list).

— Avoid excessive alcohol and large meals.

— Correct electrolyte abnormalities.

4. ICD for high/intermediate risk.

5. Quinidine as adjunct or alternative when ICD declined/contraindicated.

6. Catheter ablation (RVOT epicardium) for ICD recipients with frequent shocks.

Board pearl: Asymptomatic patient with only drug-induced type 1 and no family history → no ICD, no quinidine — just counseling, fever protocol, and the drug-avoidance list. Over-implantation is a tested wrong answer.

Three-tier risk stratification drives all decisions:

Features that raise risk in asymptomatic patients:

Features that do not independently warrant ICD:

Management framework:

Pharmacotherapy — First-Line Drug Regimen

— Mechanism: blocks transient outward K⁺ current (Iₜₒ), reducing transmural voltage gradient in RVOT.

— Indications:

— VF/electrical storm in BrS (acute and chronic suppression).

— Frequent appropriate ICD shocks.

— Patients with ICD indication who decline or cannot receive a device (children, contraindications).

— AF management in BrS (preferred over class IC, which are contraindicated).

— Dose: 600–1500 mg/day; monitor QT, GI tolerance, cytopenias.

— Side effects: diarrhea, thrombocytopenia, cinchonism, QT prolongation.

— IV infusion 1–3 µg/min to raise heart rate and augment L-type Ca²⁺ current, normalizing the ST elevation and suppressing recurrent VF.

— First-line for VF storm in a Brugada patient already defibrillated; bridge to quinidine or ablation.

— Class I antiarrhythmics: flecainide, propafenone, procainamide, ajmaline (except as diagnostic challenges).

— Tricyclic and tetracyclic antidepressants, lithium.

— Cocaine, cannabis (recreational counseling).

— Bupivacaine, propofol (high-dose/prolonged), some general anesthetics.

— Beta-blockers (worsen via bradycardia) — relative caution, not absolute.

— Acetaminophen is the antipyretic of choice; treat aggressively at ≥38°C.

— Counsel patients to seek medical care for persistent fever >24 hours or fever with palpitations/syncope.

— Rate control with diltiazem or verapamil; rhythm control with quinidine or amiodarone (caution).

— Avoid flecainide and propafenone — they unmask the substrate.

Step 3 management: Brugada patient in ED with recurrent VF despite shocks → isoproterenol drip + IV magnesium + correct K⁺ to high-normal + load oral quinidine; consult EP for possible epicardial RVOT ablation. Do not give amiodarone bolus reflexively before isoproterenol.

There is no chronic pharmacologic cure — drugs in BrS aim to suppress VF storm, serve as ICD-alternative when devices are declined/contraindicated, or treat AF.

Quinidine (class IA, Iₜₒ blocker):

Isoproterenol (acute electrical storm):

Drugs to AVOID (memorize categories):

Fever management:

AF in Brugada:

Procedures — ICD Implantation and Catheter Ablation

— Indications (Class I): Survivors of cardiac arrest, documented sustained VT.

— Indications (Class IIa): Spontaneous type 1 ECG + syncope likely arrhythmic.

— Indications (Class IIb): Inducible VF at EPS in select asymptomatic patients with spontaneous type 1.

— Device choice:

— Subcutaneous ICD (S-ICD) is often preferred — young patients, no pacing need, avoids transvenous lead complications.

— Pre-screening ECG required to confirm acceptable S-ICD vectors (some BrS morphologies fail screening).

— Transvenous ICD if pacing needed (rare in pure BrS) or S-ICD screening fails.

— Programming pearls: High detection rate cutoffs (>220–230 bpm) and long delays reduce inappropriate shocks for SVT/AF.

— Common in BrS (young, active patients with AF, sinus tach, T-wave oversensing).

— Aggressive programming, beta-blocker/quinidine for AF, lead revision if needed.

— Target: epicardial RVOT abnormal substrate (late, fractionated potentials) — mapped and ablated via subxiphoid approach.

— Indications: ICD recipients with recurrent VF/electrical storm or frequent appropriate shocks despite quinidine.

— Outcomes: ST elevation often normalizes; VF inducibility eliminated in >75%; recurrence possible.

— Emerging role: investigational as primary therapy in highly symptomatic patients; not yet standard.

— Avoid bupivacaine, propofol infusions, large doses of local anesthetics.

— Aggressive temperature monitoring and antipyresis.

— Continuous telemetry; magnet ready for ICD; defibrillator in room.

— Use neuraxial cautiously; prefer remifentanil/sevoflurane-based anesthesia.

CCS pearl: After confirming Brugada in a resuscitated VF patient, your discharge order set should include ICD implantation (cardiology/EP consult), genetic counseling referral, family screening ECGs, drug-avoidance education, and acetaminophen prescription with written fever instructions — missing any one is a commonly-tested gap.

Implantable cardioverter-defibrillator (ICD) — the cornerstone procedure:

Inappropriate ICD shocks:

Catheter ablation:

Perioperative considerations for any surgery in BrS patients:

Special Populations — Elderly and Renal/Hepatic Impairment

— Phenotype typically manifests in 3rd–5th decade; new diagnosis after age 70 is unusual — reconsider mimickers (ischemia, hyperkalemia, pulmonary embolism, ARVC).

— Event rate decreases with age in some cohorts, but ICDs already implanted should generally remain.

— Competing comorbidities (CAD, HF, cancer) may shift ICD risk-benefit; discuss deactivation in end-of-life planning.

— Polypharmacy is a major risk: antidepressants (TCAs), antiarrhythmics, antibiotics, antifungals — review BrugadaDrugs.org list at every visit.

— Quinidine is partially renally cleared (~20%); reduce dose and monitor QTc in CKD stages 4–5.

— Electrolyte derangements common in CKD/dialysis — hyperkalemia, hypocalcemia, hypomagnesemia can mimic or aggravate BrS pattern. Pre- and post-dialysis ECGs may differ markedly.

— Avoid dialyzing against low-K⁺ baths in known BrS — pursue gentler K⁺ correction.

— ICD generator changes are common; assess vascular access carefully (avoid sacrificing future AV fistula sites — left-sided implant if right arm is the planned access).

— Quinidine is extensively hepatically metabolized (CYP3A4); reduce dose in Child-Pugh B/C and monitor for toxicity (cinchonism, prolonged QT, hypotension).

— Avoid hepatotoxic concomitant drugs.

— Acetaminophen for fever — safe in usual doses; cap at 2 g/day in cirrhosis.

— TCAs (amitriptyline for neuropathy), citalopram/escitalopram (QT), trimethoprim-sulfa, fluconazole, ondansetron, lithium.

— Substitute SSRIs cautiously (sertraline is generally safer than citalopram); use duloxetine or gabapentin for neuropathic pain instead of TCAs.

Step 3 management: Elderly BrS patient admitted with pneumonia → acetaminophen scheduled q6h for fever, avoid ceftriaxone/macrolide combos that prolong QT in BrS, daily ECGs, K⁺ goal 4.0–4.5, Mg²⁺ >2.0, and continuous telemetry until afebrile.

Elderly patients with Brugada:

Renal impairment:

Hepatic impairment:

Drug interactions to flag in elderly polypharmacy:

Special Populations — Pregnancy, Pediatrics, and Women

— Pregnancy itself is generally well tolerated in BrS; arrhythmic event rate does not significantly rise.

— Peripartum fever (chorioamnionitis, endometritis, mastitis) is the principal risk — treat aggressively with acetaminophen and antibiotics.

— Avoid bupivacaine epidurals when feasible; ropivacaine or low-dose lidocaine preferred for neuraxial anesthesia.

— Continuous telemetry during labor for known BrS; defibrillator available.

— Postpartum: avoid ergotamines; oxytocin generally acceptable.

— Genetic counseling before conception — 50% transmission risk (autosomal dominant); discuss prenatal/postnatal testing options.

— Pediatric BrS is rare but high risk — events disproportionately triggered by fever in children.

— Family screening ECGs starting in childhood (some centers begin at age 8–10); fever-time ECGs are particularly informative.

— ICD decisions complicated by growth, lead longevity, psychosocial impact — S-ICD or epicardial systems considered; quinidine plays a larger role to defer or replace ICD.

— Aggressive fever protocol mandatory; written action plan given to schools and parents.

— Avoid febrile-illness drugs that aggravate BrS in pediatric formulary (ondansetron caution, avoid TCAs for headache prophylaxis).

— Lower event rate than men (testosterone-driven Iₜₒ); but women with high-risk features still warrant ICD.

— Postmenopausal women: declining estrogen does not appear to substantially shift risk.

— Preconception EP consultation; review home med list (TCAs, lithium often present).

— Lactation: quinidine is generally compatible; check current LactMed.

Board pearl: A 6-year-old with febrile VF arrest, normal echo, and coved V1–V2 ST elevation that normalizes when afebrile is Brugada — order genetic testing, refer family for cascade screening ECGs, and dispense a written fever action plan before discharge.

Pregnancy:

Pediatrics:

Women with Brugada:

Reproductive counseling:

Complications and Adverse Outcomes

— Mechanism: polymorphic VT degenerating to VF.

— Annual event rate: ~7–10% in survivors of cardiac arrest, ~1–2% with syncope + spontaneous type 1, <0.5% in asymptomatic drug-induced type 1.

— Events cluster at rest, sleep, post-prandial, febrile illness.

— Present in 10–25% of BrS patients, often young (under 50).

— Predicts worse arrhythmic prognosis.

— Complicates ICD programming (inappropriate shocks).

— PR prolongation, fascicular blocks, sinus node dysfunction — may eventually require pacing (consider dual-chamber ICD if symptomatic bradycardia coexists).

— Inappropriate shocks (most common, 20–30% over device lifetime) — SVT, AF, T-wave oversensing.

— Lead fracture/dislodgement, infection, pneumothorax (transvenous).

— S-ICD: pocket hematoma, infection, suboptimal sensing, lower energy ceiling.

— Psychological sequelae: anxiety, PTSD after shocks — screen and refer.

— ≥3 episodes of sustained VT/VF in 24 hours.

— Triggers: fever, drug exposure, electrolyte shift.

— Mortality high if untreated; rescue with isoproterenol, quinidine load, urgent ablation.

— Reported VF after propofol, bupivacaine; meticulous perioperative planning essential.

— Diagnosis carries significant psychological burden — activity restrictions, fear of shocks, genetic implications for children. Refer to support groups (SADS Foundation).

— Anoxic convulsions from VF mimic seizures; patients on antiepileptics for years before correct diagnosis.

Key distinction: A BrS patient with "breakthrough seizures" on levetiracetam is having recurrent VF, not refractory epilepsy — interrogate the ICD, get a new ECG, and reassess. Anchoring on a prior wrong diagnosis is a classic tested error.

Primary complication: sudden cardiac death (SCD)

Atrial fibrillation:

Conduction system disease:

ICD-related complications:

Electrical storm:

Anesthesia-related events:

Mood and quality of life:

Misdiagnosis as epilepsy:

When to Escalate — ICU, Consult, Inpatient Triage

— Resuscitated cardiac arrest or sustained VT/VF.

— Electrical storm (≥3 VT/VF episodes/24h).

— Recurrent appropriate ICD shocks.

— Syncope with new type 1 ECG and high-risk features (family SCD, fragmented QRS).

— Type 1 ECG newly unmasked in setting of overdose (TCA, cocaine, antiarrhythmic).

— Syncope with type 1 pattern pending workup.

— Febrile BrS patient until afebrile and asymptomatic.

— Post-ICD implantation routine monitoring.

— Suspected BrS undergoing procainamide challenge.

— Asymptomatic patient with incidentally found type 1 ECG.

— Family member of proband with abnormal screening ECG.

— Drug-induced type 1 needing further risk stratification.

— Electrophysiology — diagnostic provocation, ICD decision, ablation.

— Genetic counseling — proband and family cascade testing.

— Anesthesiology — preoperative planning for any surgery.

— Pediatric cardiology — for affected children.

— Psychiatry/health psychology — post-shock anxiety, ICD coping.

— Afebrile, normal electrolytes, no arrhythmia for 24h.

— ICD interrogated if present; programming optimized.

— Trigger drug list reviewed; alternatives prescribed.

— Acetaminophen Rx in hand with written fever action plan.

— Cardiology and (if applicable) genetics follow-up scheduled within 2–4 weeks.

— Family screening ECGs ordered for first-degree relatives.

— Driving restrictions explained (state-dependent; typically 3–6 months after VF/shock).

CCS pearl: Don't discharge a febrile suspected-BrS patient until afebrile for 24 hours with a non-type-1 ECG — a "saddleback in V2 at 38.4°C" can flip to a coved type 1 within hours and convert into the lethal phenotype overnight.

Immediate ICU admission and EP consult:

Telemetry/step-down unit admission:

Outpatient EP referral (urgent, days–weeks):

Consults to consider:

Discharge readiness checklist:

Key Differentials — Other Causes of Right Precordial ST Elevation (Same Category)

— V1–V3 ST elevation with reciprocal changes, chest pain, troponin rise, regional wall motion abnormality.

— Coved ST that resolves with reperfusion; coronary angiography diagnostic.

— Diffuse (not just V1–V2) concave-up ST elevation, PR depression, pleuritic chest pain, friction rub.

— Myocarditis: troponin elevated, MRI shows edema/late gadolinium enhancement.

— RV strain pattern: S1Q3T3, T-wave inversions V1–V3, transient ST elevation V1.

— Echo: RV dilation, McConnell sign; CTPA diagnostic.

— Epsilon wave, T-wave inversions V1–V3 in adults, late potentials on SAECG.

— MRI: RV dilation, dyskinesis, fatty infiltration — structural disease, unlike BrS.

— Exercise-induced VT (LBBB morphology) — opposite trigger from BrS.

— J-point elevation, notching in inferolateral leads; benign in most but overlaps with BrS in J-wave spectrum.

— Concave ST elevation, tall T waves; normal echo; no symptoms.

— Osborn (J) waves, bradycardia, shivering artifact; core temp diagnostic.

— Peaked T waves, widened QRS; can produce "Brugada phenocopy."

— Discordant ST elevation in V1–V3; voltage criteria and QRS duration distinguish.

Key distinction: Brugada is dynamic and provocable; STEMI is regional and reciprocal; ARVC is structural and exertional; pericarditis is diffuse with PR depression. When in doubt, repeat ECG after addressing reversible triggers (warm the patient, correct K⁺) — a true Brugada pattern persists; phenocopies resolve.

STEMI involving RV/anteroseptal territory:

Acute pericarditis / myocarditis:

Pulmonary embolism:

Arrhythmogenic right ventricular cardiomyopathy (ARVC):

Early repolarization (J-wave syndromes):

Athletic heart:

Hypothermia:

Hyperkalemia:

Left ventricular hypertrophy / LBBB:

Key Differentials — Other-Category Causes (Brugada Phenocopies)

— Hyperkalemia (K⁺ >6.5) — most common phenocopy; "pseudo-Brugada" with peaked T waves and prolonged QRS.

— Hypercalcemia, hyponatremia, hypothermia, severe acidosis.

— Hypoglycemia with autonomic surge.

— Tricyclic antidepressant overdose — widened QRS + V1 R wave + ST elevation.

— Cocaine intoxication (Na-channel blockade).

— Lithium toxicity, propofol infusion syndrome.

— Class I antiarrhythmics (flecainide, procainamide therapeutic dosing).

— Antihistamines, antipsychotics with Na-channel effects.

— Pectus excavatum, mediastinal mass (lymphoma, thymoma) compressing RVOT.

— Post-cardiac surgery, pericardial effusion.

— Pulmonary embolism with acute RV strain.

— Acute aortic dissection involving RCA ostium.

— Myocarditis with septal/RVOT involvement.

— Pericarditis with focal anterior involvement.

— Subarachnoid hemorrhage, large stroke, autonomic storms — can produce dynamic ST changes.

— Identify and reverse the trigger.

— Repeat ECG after resolution — pattern should disappear.

— If pattern persists when patient is metabolically normal and off offending drugs, pursue provocation testing for true BrS.

Board pearl: A patient brought in altered after a TCA overdose with V1 ST elevation and QRS >120 ms is not Brugada — give sodium bicarbonate, watch the QRS narrow and ST normalize, and document it as a TCA phenocopy. Reserve provocative challenge testing for after full toxin clearance.

Brugada phenocopy = type 1-like ECG pattern caused by an identifiable, reversible condition that resolves when the trigger is removed and is not genetic Brugada. Recognizing them prevents inappropriate ICD implantation.

Metabolic and electrolyte:

Drug/toxin-induced:

Mechanical/structural:

Inflammatory/infectious:

Neurogenic:

Approach when phenocopy suspected:

Secondary Prevention / Discharge Plan / Long-Term Management

— Acetaminophen Rx with explicit dosing for fever ≥38°C (e.g., 650–1000 mg q6h PRN, max 3 g/day).

— Quinidine if frequent appropriate ICD shocks, electrical storm history, or ICD declined — typically 600–1500 mg/day with QTc monitoring.

— Beta-blocker generally not indicated unless coexisting AF rate control needed (and even then, prefer diltiazem or verapamil).

— Avoid statins/other meds only if specifically contraindicated — most cardiac meds (except those on the avoid list) are fine.

— Fever protocol — antipyretics at first sign, seek care if persistent.

— Avoid offending drugs — printed list from BrugadaDrugs.org (categorized as "avoid" and "preferably avoid").

— Alert all healthcare providers (dentists, surgeons, anesthesiologists) to BrS diagnosis.

— Medical alert bracelet or wallet card.

— Moderate alcohol use; avoid binge drinking.

— Avoid large meals immediately before sleep.

— Cocaine and cannabis avoidance.

— Avoid strong magnetic fields when possible (MRI conditional safe, requires protocol).

— Driving restrictions: post-VF/shock typically 3–6 months private vehicle; commercial driving generally permanently restricted (US — varies by state).

— Annual interrogation, generator change every 5–10 years.

— Cascade screening with ECG (including high precordial leads) for all first-degree relatives.

— Genetic testing only after a pathogenic variant identified in proband.

— Pediatric relatives: serial ECGs through puberty.

— Competitive athletics: shared decision-making; no absolute ban for asymptomatic patients.

— Pregnancy planning: preconception counseling.

Step 3 management: At every BrS visit, document (1) symptoms since last visit, (2) fever events and management, (3) medication reconciliation against BrugadaDrugs list, (4) ICD interrogation if applicable, (5) family screening status — these five items are the longitudinal scaffold.

Discharge medications (variable based on phenotype):

Universal patient counseling (apply to ALL phenotypes, even drug-induced asymptomatic):

ICD recipients:

Family management:

Lifestyle:

Follow-Up, Monitoring, and Counseling

— Initial post-diagnosis: EP visit within 2–4 weeks.

— Stable asymptomatic: annual EP/cardiology follow-up with ECG.

— ICD recipients: in-clinic visit q6–12 months + remote monitoring with weekly/monthly transmissions.

— Post-shock: within 1–2 weeks for device interrogation, medication review, psychological screen.

— Post-ablation: 1, 3, 6, 12 months, then annual.

— Pediatric patients: every 6–12 months with growth-adjusted ECG and family history update.

— Symptoms: syncope, palpitations, "seizures," shocks.

— Fever episodes and management adherence.

— Medication reconciliation — especially new prescriptions from other providers.

— 12-lead ECG (including high V1/V2 leads periodically).

— Electrolytes (K⁺, Mg²⁺) if on quinidine or diuretics.

— Quinidine level/QTc if applicable.

— Mood screen (PHQ-2/GAD-2) particularly post-shock.

— Detects shocks, lead issues, AF burden between visits.

— Patient education on transmitter use and what to do if shock received (calm, sit/lie down, call if multiple shocks or symptomatic).

— Reinforce trigger avoidance at every visit — adherence drifts.

— Update medication list each visit against BrugadaDrugs.org.

— Reproductive and family-planning counseling, especially in adolescents transitioning to adult care.

— Driving status review per local regulations.

— Travel: carry medication list, device ID card, recent ECG.

— No formal cardiac rehab needed (no ischemic substrate).

— Encourage moderate activity; individualized return-to-sport plan post-event.

— Psychological counseling/support groups (SADS Foundation, ICD support).

Board pearl: A BrS patient on quinidine who suddenly develops diarrhea and dizziness — check quinidine level, QTc, and electrolytes. Quinidine-induced volume depletion and hypokalemia paradoxically raise both QT and BrS-related VF risk. Adjust dose or switch strategy.

Follow-up cadence:

Monitoring parameters at each visit:

Remote ICD monitoring:

Counseling content:

Rehabilitation:

Ethical, Legal, and Patient Safety Considerations

— Procainamide/ajmaline challenges carry small but real risk of VF or sustained VT.

— Document discussion of: purpose, risks (arrhythmia, death), alternatives (high-lead ECG, prolonged monitoring), and that a defibrillator/ACLS team will be immediately available.

— Pre-test counseling: discuss implications for relatives, insurance (GINA protects health insurance but NOT life/disability/long-term-care insurance in the US), psychological impact, and possibility of variants of uncertain significance.

— Cascade testing of minors: generally appropriate given pediatric SCD risk in BrS — different from adult-onset conditions like Huntington's. Involve pediatric genetic counselors.

— Right not to know: relatives may decline testing; respect autonomy while emphasizing the actionable nature of BrS (fever protocol, drug avoidance) even without an ICD.

— Especially for intermediate-risk patients, present numerical event rates, ICD efficacy, and complication risks (inappropriate shocks 20–30% lifetime).

— Document the discussion; revisit periodically as risk profile changes.

— In terminal illness, deactivate the ICD to prevent painful shocks while dying — ethically equivalent to withholding/withdrawing other life-sustaining therapy.

— Document discussion with patient/surrogate; use a magnet or device reprogramming.

— Post-VF or post-shock private driving restriction typically 3–6 months; commercial licensure often permanently restricted.

— In some states physician reporting is mandatory (e.g., California, Pennsylvania); know your jurisdiction.

— At every handoff (ED→floor, hospital→PCP, pediatric→adult care), the BrS diagnosis, drug-avoidance list, fever protocol, and ICD device card must be communicated — failures here cause preventable deaths.

— Pre-employment ECGs may incidentally find BrS; counsel against discriminatory employment decisions; document accommodations.

Step 3 management: A hospice patient with a Brugada ICD who is actively dying — call the device clinic for immediate deactivation or place a magnet over the generator to inhibit shocks. Failing to do so causes preventable suffering and is a tested patient-safety failure.

Informed consent for diagnostic provocation testing:

Genetic testing ethics:

ICD shared decision-making:

End-of-life and ICD deactivation:

Driving restrictions:

Transition-of-care safety:

Workplace and athletics:

High-Yield Associations and Rapid-Fire Clinical Facts

Board pearl: If the stem mentions "young Asian man, found dead in bed, autopsy normal" — the answer is Brugada syndrome until proven otherwise, even if no ECG is shown. Test families.

Genetics: SCN5A loss-of-function (autosomal dominant, ~20–30% of probands); >20 other genes implicated but lower yield.

Demographics: Male:female ~8:1; Southeast Asian predilection; mean age at diagnosis ~40.

Triggers (memorize): Fever, sleep, large meals, alcohol, cocaine, TCAs, Na-channel blockers, hypokalemia, bradycardia.

Diagnostic ECG: Coved ≥2 mm ST elevation in V1 and/or V2 (type 1) — only type 1 is diagnostic.

Maneuver: Move V1/V2 up to 2nd or 3rd intercostal space to unmask.

Provocation drugs: procainamide (US), ajmaline (Europe), flecainide.

Risk stratification: Highest risk = aborted SCD; intermediate = syncope + spontaneous type 1; lowest = asymptomatic drug-induced type 1.

Definitive therapy: ICD for high/intermediate risk; quinidine as adjunct or ICD-alternative.

Acute electrical storm rescue: Isoproterenol infusion + oral quinidine load.

AF: Common (10–25%) in young BrS — avoid flecainide/propafenone; use quinidine or rate control.

ARVC vs. BrS: ARVC has structural RV disease and exertional VT (LBBB morphology); BrS is structurally normal with rest/sleep VF.

LQT3 vs. BrS: Same gene (SCN5A) — LQT3 is gain-of-function, BrS is loss-of-function ("overlap syndrome" possible).

Sudden infant death syndrome (SIDS): Some cases linked to SCN5A — family history clue.

Acetaminophen is the only board-approved antipyretic emphasis — fever management is the single most actionable lifelong measure.

S-ICD preferred over transvenous in many BrS patients (young, no pacing need).

BrugadaDrugs.org — the canonical drug-avoidance reference.

SADS Foundation — patient advocacy and family support.

Quinidine acts via Iₜₒ blockade — the only proven oral therapy for substrate modification.

Driving — VF/shock typically off-limits for 3–6 months private use.

GINA protects health insurance but not life/disability insurance — counsel before genetic testing.

Board Question Stem Patterns

— "30-year-old man, syncope at rest, ECG shows saddleback V1–V2. What next?"

— Answer: Sodium-channel blocker challenge (procainamide) OR high right precordial lead placement.

— Distractor: "Reassure" (wrong — must rule out type 1).

— "6-year-old with febrile illness has VF arrest; defibrillated; echo normal; ECG shows coved V1–V2 ST elevation that normalizes when afebrile."

— Answer: Brugada syndrome; ICD or quinidine depending on subtleties; family cascade ECGs.

— Patient with depression started on amitriptyline develops new V1–V2 ST elevation."

— Answer: TCA phenocopy / Brugada unmasking — stop TCA, repeat ECG; if pattern persists, work up as BrS.

— "Father died suddenly at 38; 24-year-old son brings family ECG."

— Answer: Obtain ECG with high precordial leads, consider provocation if non-diagnostic, refer for genetic counseling.

— "Brugada patient with ICD has palpitations and 3 shocks today; rhythm strip shows AF with RVR."

— Answer: Rate control with diltiazem; reprogram ICD; consider quinidine; avoid flecainide.

— "Brugada patient post-VF arrest with recurrent VF despite amiodarone."

— Answer: Isoproterenol infusion + load quinidine; consult EP for ablation.

— "Patient with BrS scheduled for cholecystectomy."

— Answer: Continuous telemetry, avoid bupivacaine/high-dose propofol, antipyresis, defibrillator in room, ICD interrogation.

— "Brugada patient with metastatic cancer enrolled in hospice has ICD."

— Answer: Deactivate ICD after discussion with patient/family.

— "Pre-employment ECG shows type 2 saddleback V1–V2 in asymptomatic 35-year-old without family history."

— Answer: Reassure, no ICD; high-lead ECG and possible provocation if type 1 emerges; counsel triggers regardless.

Board pearl: When the stem says "young, rest/sleep, fever, or family SCD" combined with V1–V2 ST changes, the correct path runs through Brugada — and the management answer is rarely amiodarone.

Stem 1 — The unmasked diagnosis:

Stem 2 — Fever-triggered event:

Stem 3 — Drug-induced unmasking:

Stem 4 — Family screening:

Stem 5 — Inappropriate ICD shocks:

Stem 6 — Electrical storm management:

Stem 7 — Pre-op planning:

Stem 8 — End-of-life ethics:

Stem 9 — Asymptomatic incidental finding:

One-Line Recap

Brugada syndrome is an inherited SCN5A-linked sodium channelopathy producing dynamic coved ≥2 mm V1–V2 ST elevation in a structurally normal heart, where management hinges on ICD for survivors of cardiac arrest or syncope with spontaneous type 1 ECG, lifelong fever and drug-trigger avoidance for all phenotypes, and quinidine plus isoproterenol for electrical storm.

Board pearl: When a stem features a young patient with rest/sleep/febrile syncope, V1–V2 ST changes, a normal echo, or a family history of unexplained early SCD — the answer is Brugada syndrome, and the management answer is almost never amiodarone or class I antiarrhythmics; it is ICD, quinidine, isoproterenol, acetaminophen, and family screening.

Diagnosis: Type 1 coved ST elevation ≥2 mm in V1 and/or V2 — spontaneous or unmasked by procainamide/ajmaline, fever, or high right precordial lead placement.

Risk tiers: Aborted SCD → ICD (Class I); syncope + spontaneous type 1 → ICD (Class IIa); asymptomatic with only drug-induced type 1 → counseling and trigger avoidance, no ICD.

Universal interventions (every patient, every visit): Aggressive acetaminophen for fever ≥38°C, lifelong avoidance of BrugadaDrugs-listed agents (TCAs, class I antiarrhythmics, cocaine), moderation of alcohol/large meals, medical alert documentation, and family cascade ECG screening.

Acute electrical storm: Isoproterenol infusion (1–3 µg/min) plus oral quinidine load; magnesium and potassium repletion; epicardial RVOT ablation if refractory — not amiodarone first.

Step 3 longitudinal scaffolding: Annual EP follow-up, remote ICD monitoring, medication reconciliation against the avoid list, pre-operative anesthesia consultation for any surgery, deactivation of ICD at end of life, and ongoing genetic counseling for family planning — every handoff must transmit the diagnosis, the drug-avoidance list, the fever action plan, and the device card.