IJCS | Volume 32, Nº2, March/April 2019

DOI: 10.5935/2359-4802.20190015 102 EDITORIAL International Journal of Cardiovascular Sciences. 2019;32(2)102-103 Mailing Address: Claudio Tinoco Mesquita Pós-Graduação em Ciências Cardiovasculares, Avenida Marques do Paraná, 303. Postal Code: 24033-900, Centro, Niterói, Rio de Janeiro, RJ - Brazil. E-mail: claudiotinocomesquita@id.uff.br Carnival and Energy Drinks: a Dangerous Combination to the Heart Claudio Tinoco Mesquita 1, 2 Universidade Federal Fluminense, 1 Niterói, RJ - Brazil Hospital Pró-Cardíaco, 2 Rio de Janeiro, RJ - Brazil Carnival; Brazil; Dancing/trends; Music; Alcoholic Beverages; Cannabis; Atrial Fibrillation; Cafeine/adverse effects; Hospitalization; Arrhythmias, Cardiac. Keywords Everything being a constant carnival, there is no carnival left. Victor Hugo Every year, millions of people of different ages and origins go to the streets in many countries around the world to celebrate carnival (Figure 1). In Brazil, the most popular carnival celebrations and parades take place in the city of Rio de Janeiro and in the Brazilian states of Bahia and Pernambuco. Rio de Janeiro’s carnival alone drewmore than 5 million people in the last years. One of the most common activities during carnival is taking part in the Samba Parade, a beautiful festival where people dance on the streets. Samba dance requires vigorous and variedmovements that can promote happiness and intense chronotropic response. One study demonstrated that during samba sessions, individuals can reach 60-90% of maximal heart rate predicted for age at 86% of time. 1 Drinking alcohol is also very frequent during carnival, and its combination with energy drink (ED) intake has increased lately. And what would be the effects of this combination to the heart of people that want to celebrate this festivity? Drinking is associated with atrial fibrillation (AF) in a situation called“HolidayHeart Syndrome”. Bingedrinking and evenmild-to-moderate alcohol (sevendrinks perweek or more) increases the incidence of AF. 1 Some studies have shown that the use of other substances associated with binge drinking, such as the recreational use of marijuana, may contribute to the increase in AF incidence. In a recent study, Desai et al. 2 observed that 2.7% of recreational marijuana users developed arrhythmia with a steadily increasing trend from 2010 through 2014, and that AF was the most common subtype of arrhythmia among hospitalized marijuana users. 2 The association of alcohol andmarijuana shouldbe greatlyavoidedbecause it doubles the odds of drunk driving, negative social consequences, and harms to self besides cardiac adverse effects. 3 Energy drinks are legally allowed and can even be sold in schools. The marketing for ED consumption is targeted toward young adults aged between 18 and 34 years, and this strategy succeeded because EDs have been one of the fastest growing segments in the beverage industry. 4 These drinks can have very high amounts of caffeine and other “energy-boosting” additives that have been linked with many reports of atrial and ventricular arrhythmias. 1 In addition to their proarrhythmic effects, the consumption of EDs is associated with significant hemodynamic overload. Grasser et al. 5 demonstrated that the ingestion of one can ((355-mL) of a sugar-sweetened ED resulted in an augmented workload to the heart as evidenced by elevated blood pressure, heart rate, cardiac output, and double product values. 5 The hallmark feature of EDs is their high caffeine content. Caffeine is a methylxanthine alkaloid that stimulates the central nervous system. Caffeine has a half-life of 5.7 h, nearly 100% bioavailability, and its maximum concentrations are reached within one hour of consumption. 6 Caffeine activates the sympathetic nervous systemand can act as an antagonist of the neuromodulator adenosine leading to elevations in blood pressure. It elevates the sinus rate by sympathomimetic effects mediated by phosphodiesterase inhibition and raises cytoplasmic calcium. 6 ED ingestion has been associated with arrhythmias even inpatientswith structurally normal hearts. Fletcher et al. 7 compared the effects of caffeine alone and EDs in healthy volunteers and demonstrated