Brugada Syndrome: A Look at the “Might Be” and “Maybe” in Diagnosis and Treatment

In this next case installment from the Florida Hospital Zephyrhills, the authors describe a diagnosis of Brugada Syndrome, leaving the authors with questions about “might be” and “maybe” conclusions.

Introduction

A 28-year-old Caucasian male presents to the Emergency Room (ER). He is a nursing student and admits he has been under an increased amount of stress as of late. His chief complaint is “palpitations.” He denies any episodes of syncope, lightheadedness, or dizziness. He has known history of hypertension (HTN), insulin-dependent diabetes mellitus (IDDM), and hyperlipidemia. Home medications include: Lexapro 10mg daily, lisinopril 20mg daily, Humalog insulin 4 units subcutaneous every evening, and hydrochlorothiazide 12.5mg daily. The patient denies any use of alcohol, tobacco, or illicit drugs. Family history includes the sudden death of three cousins, all under the age of 45, etiology unknown.

Diagnostics

Initial workup in the ER includes the following:

• Basic metabolic panel: within normal limits; including blood glucose level
• Complete blood count: within normal limits, including white blood cell count
• Vital signs: blood pressure 149/95; pulse 97bpm; respirations 18; oxygen saturation 100%; temperature 97ºF
• Electrocardiogram (ECG): Significantly abnormal, revealing marked ST segment elevations in V1 and V2 with inverted T-waves and pseudo right bundle branch block pattern
• Cardiac marker: troponin < 0.01

Assessment

1. ECG findings were consistent with Brugada Syndrome; specifically Type 1
2. Patient having palpitations most likely due to Brugada Syndrome
3. Echocardiogram ordered to evaluate ejection fraction (EF) and assess for any structural abnormalities
4. Stress test ordered to evaluate for any possible ischemia
5. Admit patient to the telemetry floor to monitor for possible ventricular arrhythmias

Consultations

A cardiologist and an electrophysiologist were consulted to assist in the treatment of this high-risk patient. The cardiologist concurred with the findings and subsequent diagnosis of Brugada Syndrome and awaited further recommendations from the electrophysiologist, specifically relating to the need for an EP study (EPS) and/or implantation of an implantable cardiac defibrillator (ICD). At this time, echocardiogram revealed a structurally normal heart with an estimated EF of 65%. Stress test had been performed and the results revealed no signs of ischemia.

The electrophysiologist also concurred with the diagnosis of Brugada Syndrome, specifically Type 1, but was unsure if the “palpitations” the patient was describing were being brought on by his increased amount of stress or by the Brugada Syndrome. He was not completely convinced that the palpitations were true symptoms manifesting the rare diagnosis…in other words, could they have been a mere coincidence? However, he was certain that this patient presented with the classic EKG pattern for Type 1 Brugada Syndrome, and had the family history (to include sudden death) to support cause for concern.

The electrophysiologist had a long discussion with the patient to explore his treatment options, including EPS and/or ICD implant. Risks and benefits of treatment were discussed at length, as well as the high risk of mortality that this diagnosis incurs. The patient decided to forego the EPS given the suboptimal sensitivity and specificity of the procedure. After much debate, the patient opted for the implantation of a single-chamber ICD for secondary prevention of sudden cardiac death (SCD). The ICD was implanted without complication. No new medications were recommended by the electrophysiologist because no drugs have been proven to prevent SCD in the treatment of Brugada Syndrome, as stated in his consultation note.

Brugada Syndrome: Defined and Diagnosed

Brugada Syndrome is a genetic disease that is characterized by abnormal ECG findings and an increased risk of SCD. It is the major cause of sudden unexpected death syndrome, and is the most common cause of sudden death in young men without known underlying cardiac disease in Thailand and Laos.¹ The disease is characterized by the lack of structural heart disease and an ECG with a characteristic coved-type ST-segment elevation in leads V1, V2, and V3. Syncopal episodes and paroxysmal palpitations are the only symptoms attributable to the disease that may warn before (aborted) sudden arrhythmic death occurs. The QRS pattern of patients with Brugada Syndrome may show complete right bundle branch block (RBBB), incomplete RBBB, or “focal” RBBB.² Diagnosis of Brugada Syndrome requires ruling out conditions known to cause sudden cardiac death unless such conditions are acquired after the establishment of Brugada Syndrome. A complete workup of a symptomatic patient with Brugada ECG pattern may require, in addition to the routine history, physical examination and ECG, a transthoracic or transesophageal echocardiogram, coronary angiogram, stress test, magnetic resonance imaging and, in some cases, myocardial biopsy.³

Treatment Options

Currently, implantation of an ICD is the only effective treatment for this syndrome. However, risk stratification of asymptomatic patients with Brugada type ECG is still a challenge. In particular, the use of EPS for risk stratification remains controversial — no precise predictor of risk of SCD in asymptomatic patients has yet been determined.⁴ Priori et al found that 14% of patients with spontaneously abnormal Brugada type ECG without previous syncope suffered cardiac arrest during a mean follow up of 34 months as well as a relatively high risk of SCD.⁴ Eckardt et al found that only 0.8% of patients without a previous cardiac arrest or syncope had SCD and documented ventricular fibrillation during a mean follow up of 40 months. They also reported that one of the significant predictors for risk of SCD was a spontaneously abnormal type 1 ECG.⁴ Although the risk of SCD in sporadic asymptomatic patients may be much lower, a spontaneously abnormal type 1 Brugada ECG might be a predictor for SCD in these patients.4 The predictive value for inducibility of sustained ventricular arrhythmias during EPS is still controversial.4 Another study recommends ICD implantation for asymptomatic patients with a family history of SCD and type 1 Brugada ECG.⁴ There has been some lack of uniformity in the diagnostic criteria and protocols for EPS, and follow-up periods have been limited.⁴ Although the NCDR registry is collecting data on all ICD implantations, its accuracy is not known.

Conclusion

Clearly, our physicians felt it necessary to weigh the risks for this patient. Our board-certified cardiologist and electrophysiologist spent time with the patient and educated him on his treatment options. Certainly this patient had the Brugada type 1 ECG pattern with RBBB, but did one episode of “palpitations” qualify his particular disease to be “symptomatic”? Does the sudden death of three cousins qualify as family history of Brugada Syndrome when their exact cause of death is unknown? Did he fit the criteria for an ICD implant? The “might be” and “maybe” conclusions of our research did not answer our questions. The published studies on this disease cannot clearly identify the best treatment for these patients. In our opinion, there was no other choice but to implant an ICD to protect this young, 28-year-old father from sudden cardiac death.

References

1. “Brugada syndrome.” Wikipedia. 2011. Accessed April 4, 2011. https://en.wikipedia.org/wiki/Brugada_Syndrome
2. Brugada P, Brugada R, Brugada J. Should patients with an asymptomatic Brugada electrocardiogram undergo pharmacological and electrophysiological testing? Circulation 2005;112:279–292.
3. Surawicz B. Brugada syndrome: Manifest, concealed, “asymptomatic,” suspected and simulated. J Am Coll Cardiol 2001;38:775–777.
4. Takagi M, Tatsumi H, Yoshiyama M. Approach to the asymptomatic patients with Brugada syndrome. Indian Pacing Electrophysiol J 2007;7:73–76.
5. Dizon JM, Nazif TM. “Brugada syndrome.” eMedicine.medscape.com/article/16371. Pg. 1