Red Bull “Gives You Wings”
Rockstar – “Party Like A Rockstar”
Monster – “Unleash The Beast”
We have all heard these slogans and most of us have fallen prey to their promises at one time or another. In the not so distant past, I was working overtime, taking extra call shifts, and consuming at least two Rockstars a day. Sound familiar?
While walking into a hospital, a physician (that I had never met) stopped me when he saw my drink of choice in hand. He warned me that drinking energy drinks may lead to atrial fibrillation. Little did he know, I was arriving to assist with an AFib procedure. This was not news to me, but the irony did make me consider my choices… I now have been energy drink free for five years.
Red Bull was created in 1987 by Dietrich Mateschitz in Austria, and it was first released in the US in 1997. By 2005, there was an explosion of energy drink sales. The global market in 2018 was valued at $53 billion and is expected to reach $86 billion by 2026.
Energy drinks claim to increase focus and improve performance; although, I mainly felt very jittery. This is due to the amount of caffeine as well as added stimulants. The health effects of these additives are not well documented.
Stimulants include:
- Guarana: An herb used to prevent tiredness and improve mental speed.
- Taurine: A supplement used to improve memory and endurance.
- Ginseng: An herb used to help reduce stress, strengthen muscles, and improve endurance.
- Synephrine (bitter orange): An herb used to promote weight loss.
- L-carnitine l-tartrate (LCLT): A supplement used to increase energy, memory, and speed.
- Yerba mate: An herb used to prevent tiredness and improve mood.
- Gingko: An herb used to increase focus and prevent tiredness.
The caffeine added to energy drinks is synthetic unlike the natural caffeine in tea or coffee. Some of the other additives such as guarana and yerba mate also contain caffeine. Therefore, the total amount listed on the product label may not be accurate. Energy drinks vary with 71-316 mg of caffeine per 8 oz. serving, exceeding the FDA-imposed limit of 71 mg per 12 fluid oz. of soda [1].
To make matters worse, the half-life of caffeine increases by 72% when paired with alcohol. High doses of caffeine are associated with palpitations, atrial fibrillation, and ectopy. The blood pressure may rise acutely causing stress to the cardiovascular system, which increases the likelihood of arrhythmias [2].
Caffeine in energy drinks is metabolized into methyl-xanthine. This acts by inhibiting phosphodiesterase, antagonize adenosine receptor and increases catecholamine secretion. At high doses, the following may be observed; tachycardia, increased blood pressure, diuresis, vomiting, diarrhea, bronchodilation, gastric acid secretion, and central nervous system stimulation may be seen. The main toxicity caused by caffeine is due to the increase in intracellular calcium concentration, which leads to a catecholamine surge that sensitizes dopamine receptors resulting in supraventricular or ventricular arrhythmias and death [3].
The following chart demonstrates the various cardiac effects observed with energy drink consumption. These beverages are also associated with epileptic seizures, stroke, subarachnoid hemorrhage, pontine myelinolysis, hallucinations, anxiety, agitation, headaches, hepatitis, gastrointestinal upset, acute renal failure, rhabdomyolysis, metabolic acidosis, insulin resistance, obesity, acute psychosis, insomnia, high risk/aggressive behavior and caffeine withdrawal [1].
Energy drinks should not be consumed:
- By adolescents or children
- For hydration prior to, during, or after exercise or physical activity
- With alcohol
- Close to bedtime
Knowing this information, why would you consume an energy drink? In my opinion, it is not worth the price you pay financially or with your health. Although I still do turn to coffee and tea daily, I often opt for a decaf version and work on increasing my energy level naturally. Turn to other sources such as getting enough sleep, a well-rounded diet, regular exercise, and water consumption.
Blog Post References:
[1] Higgins, J. (2018, Feb. 28). Stimulant-Containing Energy Drinks. Retrieved from https://www.acc.org/latest-in-cardiology/articles/2018/02/28/10/46/stimulant-containing-energy-drinks.
[2] Wassef, B., Kohansieh, M., Makaryus, A. (2017, Nov. 26) Effects of energy drinks on the cardiovascular system. PMID: 29225735. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5714807/.
[3] Muacevic, A., Adler, J. (2017, Jun 7) Energy Drinks and the Risk of Cardiovascular Disease: A Review of Current Literature. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5501707/
This week’s EP question:
This medication has a profound but fleeting depressive effect on the SA and AV nodes.
1. Quinidine
2. Adenosine
3. Amiodarone
4. Sotalol
Answer
Adenosine
Intravenous adenosine may be used to convert paroxysmal supraventricular tachycardia (PSVT) to sinus rhythm if the tachycardia is dependent on AV nodal conduction. Adenosine does not convert atrial flutter, atrial fibrillation, or ventricular tachycardia. However, in the presence of atrial flutter or atrial fibrillation, a transient AV block will be observed. This will assist in the diagnosis of the underlying rhythm. The first dose of adenosine is typically 6 mg administered rapidly over 1-3 seconds followed by a 20 ml normal saline bolus. If AV nodal block is not observed, a 12 mg dose may be given in a similar fashion.
Adenosine may also be used to induce atrial fibrillation due to shortening of the atrial action potential duration and atrial refractoriness. This is particularly worth noting in a patient with a history of WPW. Blocking the AV node in a WPW patient may allow for more impulses to travel rapidly to the ventricle via the antegrade conducting pathway. If atrial fibrillation were induced, this could be problematic.
Adenosine may be helpful in the diagnosis of accessory pathways. Once the AV nodal block is observed, ventricular pacing is performed. This may reveal conduction from the ventricle to the atrium over an accessory pathway. The reverse is also true in diagnosing antegrade conducting pathways.
