You may have Brugada syndrome without any symptoms. If you have symptoms, they usually appear in young adulthood and occur at night or at rest in the daytime and may include: racing or irregular pulse (palpitations) feeling dizzy and faint cardiac arrest, if your heart suddenly stops beating (very rare) Some unexplained sudden deaths may be caused by cardiac arrest due to Brugada syndrome. Brugada syndrome is the most common inherited cardiac cause of sudden death in people aged under 40 years of age.