Holiday heart syndrome is a clinical entity characterized by the development of cardiac arrhythmias associated with binge drinking and excessive alcohol consumption. The condition is transient and resolves spontaneously after abstinence from alcohol. The diagnosis can be made only after confirming a recent history of heavy alcohol drinking while physical examination and electrocardiography are used to diagnose cardiac arrhythmias.
Holiday heart syndrome (HHS) was initially described in the late 1970s in individuals who consumed excessive amounts of alcohol during the holiday seasons and weekends (either on a regular basis or "binge" drinkers) and developed various forms of cardiac arrhythmias   . Scarce reports exist on the topic, but studies have determined that individuals who consume > 60 grams (or even > 36 grams) of pure ethanol/day are at a significant risk for atrial fibrillation (AF), the principal arrhythmia seen in patients with HHS   . The exact pathogenesis remains to be elucidated, but sudden intake of large amounts of alcohol seems to reduce the refractory period of the right atrium, impair vagal tone and promote conduction blocks . When AF is present, patients can complain of dyspnea, palpitations, presyncope, weakness, light-headedness and fatigue . In some individuals, an association between alcohol consumption and heart failure has been made, which is supported by the confirmed ability of alcohol to induce oxidative stress, electrolyte imbalance, scarring of the cardiac tissue and a negative inotropic effect by disrupting the activity of calcium channels  . Heart failure, however, is more commonly related to chronic alcohol abuse, whereas HHS is an acute deterioration resulting from excessive amount of intake over a short period of time.
As HHS is a syndrome related to binge drinking during the holidays or weekends, a detailed patient history is essential to point towards the diagnosis. A recent history of consumption of large amounts of alcohol or attending some events or celebrations can provide an inital clue, while physical examination can confirm alcohol intoxication and arrhythmias. Alcohol in the patient's breath and irregular pulses may be often encountered . A heterogeneous anamnesis from friends or family members is favorable if the patient is not competent to provide adequate data, or if patients deny alcohol consumption. If signs of cardiac conduction abnormalities are present, electrocardiography (ECG) should be performed promptly. Typical findings of Atrial Fibrillation(AF) on ECG are absence of P waves, irregular R-R intervals and QRS complexes with fibrillatory (f) waves appearing at rates as high as > 300/min) . If AF is confirmed, cardiac ultrasonography is recommended, in order to assess the entire cardiac apparatus and determine whether additional abnormalities, such as scarring, atrial or ventricular dysfunction, and other signs of myocardial injury are present. Assessment of serum electrolyte levels (especially potassium levels) and thyroid hormone levels are recommended in the initial workup as well .