This series of posts regarding Brugada Syndrome (BrS) started due to my recent literature search and reading up on the disease. Following recent discussions regarding the disease with co-workers that are experts on genetics, I've been slowly reminded of the fascinating genetic causes of the disease.

My personal interests however, are more interested in the electrophysiology/mechanism of disease. As previously mentioned, a large proportion of affected individuals have mutations in the SCN5A voltage-gated sodium channel, although many other genes are being implicated. A recent editorial by Viskin in Circulation is a great read I would recommend. The disease is rare, and Viskin analyzes the current approach for care provided to children with the disease with what I believe is an important discussion regarding treatment options, considering that many children with BrS are asymptomatic.

One aspect of the disease that I recently found interesting was gender differences. BrS is known to be a genetic disorder with an autosomal dominant pattern of inheritance, therefore we would expect males and females to be equally likely to inherit a defective gene from the parent. The quite fascinating aspect however, is that the majority of carriers of the disease who actually develop arrhythmias or other symptoms are later in adulthood (mean age of 34-53 years) and also >90% male.

Based on the reported mechanism and greater proportion of affected males, there are reports hypothesizing hormonal changes (specifically related to testosterone which would exacerbate the sodium channel defect) during puberty to account for this apparent inequality in gender.

The story becomes quite interesting when we consider the gender distribution in paediatric populations. Probst and colleagues reported no obvious male predominance among symptomatic or asymptomatic children with BrS in a sample of 30 children and adolescents (less than or equal to 16 years of age). This supports the proposed model of disease progression being linked to hormonal changes during puberty, as a paediatric population would not have undergone these changes in testosterone levels resulting in an equal distribution of males and females.

This is a bit of a sidetrack from Brugada Syndrome (BrS) and BrS in children specifically.

Through my work at The Hospital for Sick Children, one organization that I have been exposed to indirectly is the SADS Foundation. SADS stands for Sudden Arrhythmia Death Syndromes, an organization which focuses on the types of rhythm disorders that I am involved with through my work at SickKids.

Sudden cardiac death (which in certain diseases is associated with exercise specifically) is a concern for a number of arrhythmias/other arrhythmogenic diseases. It is quite unfortunate that due to the risk of death, it is not the best clinical symptom to screen for. This is why a number of preventative measures are important, and the emerging use of exercise stress tests in patient diagnosis in addition to preventative treatments such as ICD implant.

For more on SADS check out the following links:

http://www.sads.ca/
http://www.sads.org/What-is-SADS/Brugada-Syndrome

The tragedies of the tsunami in 2011 that occurred in Japan was a catastrophe. Commonly referred to as "Fukushima", due to the meltdown that occurred at the Fukushima and Daiichi nuclear power plants. Many have seen the images of the plants "spewing" radioactive materials into the Pacific Ocean. Fear of what this radiation was going to do to wildlife in the ocean, and more pressingly human effects (due to consumption of products such as fish) led to widespread panic. For years following the accident, there was fear that reached as far wide as the western coast of North America, fearing the effects of consuming "contaminated fish".

With respect to the radiation effects, Fukushima is a perfect example of uneducated fear and paranoia. When discussing the accident in a radiobiology course, our instructor told us one fact - not a single death to this day from Fukushima can be attributed directly to acute radiation exposure. The number of lives lost was a cause of the earthquake and subsequent tsunami and the additional panic caused by immediate evacuation of inhabitants surrounding the plants.

Yet, when the word Fukushima is mentioned, the first image that is seen is that nuclear powerplant meltdown. This topic was recently brought into mainstream public media through an article published in the New York Times:

http://www.nytimes.com/2015/09/22/science/when-radiation-isnt-the-real-risk.html?_r=1

Although Fukushima is a true tragedy, it was really a natural disaster. It is important to begin to understand what possible effects may be related to radiation release, this accident illustrates the level of mass panic and fear that is induced by any mention of nuclear power. Particularly in the science community, it is important to be careful of understanding radiation and radiological effects. This sentiment should also be shared by news media, as they are the primary point of communication with the general public.

As I continued my literature review/readings into Brugada Syndrome (BrS) I came across quite the unique image.

Although diagnosis of BrS is a complex process involving various electrophysical tests to provide a conclusive diagnosis, one general "hallmark" of the disease is ST-segment elevation in the right precordial leads (V1-V3). I came across a powerpoint presentation which included BrS (link provided at the end of this post).

This person simply concluded that "Brugada = Sailboat of Death in Leads V1-V3)", as the large ST segment elevation could visually be similar in appearance to the sails on a sailboat. What a random, yet interesting little analogy. Now whenever I see a sailboat on the open water, I will be reminded of Brugada!

http://www.slideshare.net/islamghanem/brugada-casepresentation [SLIDE 9]
Islam Ghanem -Assistant lecturer of cardiology-Zagazig

I thought I'd start off my first official blog post with something I've been working on for the past few weeks. I recently analyzed a data set that had to do with ECG parameters in Brugada Syndrome (BrS) in a paediatric population. Although I cannot share details regarding my dataset specifically as the results of my analysis/the dataset are not published, just conducting background reading on this disease opened my eyes to a disease that is rare and as you can therefore guess not widely known among the general public. Since there is so much I could discuss from all of my readings, I will split this up into multiple posts.

Brugada Syndrome (BrS) is an inherited cardiac disorder, first identified by the Brugada brothers in 1992 to be a clinically distinct syndrome. Patients with BrS are at risk for sudden cardiac death, with generally no observed structural abnormalities observed in the heart. BrS is classically characterized by ST segment elevation in leads V1-V3 (for more review papers/background see some sample references below). Overall, the mechanism for disease progression is largely associated with mutations in the SCN5A sodium voltage gated channel.

This is a quick background on this rare disease. After reading these kinds of reviews for the disease as a whole, my focus shifted towards reports on paediatric BrS due to the research questions associated with the dataset I was working with. Stay tuned for more on how the story becomes quite interesting when we consider reports of BrS in children, and how the disease isn't identical as we know it in adults!

• Berne, P., & Brugada, J. (2012). Brugada syndrome 2012. Circulation Journal, 76(7), 1563-1571.
• Brugada, P., Brugada, R., & Brugada, J. (2000). The Brugada syndrome. Current Cardiology Reports, 2(6), 507-514.
• Brugada, P., & Brugada, J. (1992). Right bundle branch block, persistent ST segment elevation and sudden cardiac death: a distinct clinical and electrocardiographic syndrome: a multicenter report. Journal of the American College of Cardiology, 20(6), 1391-1396.

Welcome to my first of (hopefully) many blog posts!

Trained primarily as a physiology student, radiation biology is a fascinating field that I am learning about everyday! Whether it is learning new topics or debates in the field of low dose radiation research or discovering new ways in which radiation interacts with biological systems; I hope to spread this knowledge!

On the flip side, working for a paediatric cardiologist and electrophysiologist, the world of cardiology is equally as marveling. Whether it is observing cases in the cath lab and seeing, first hand, the type of expert care that goes into procedures or just learning about the complex mechanisms underlying various arrhythmias or other arrhythmogenic diseases, I feel like that the world of EP cardiology has so much to offer. Being able to learn from a paediatric cardiologist, and how these mechanisms are changed or differ in children is quite the unique and amazing opportunity!

Check back for more posts and feel free to drop a comment below.