This cardiology presentation discusses 4 patient cases. The first case involves a 45-year-old woman with shortness of breath, low heart voltage, premature ventricular contractions, and signs of pericardial effusion on echocardiogram. The second case is a 41-year-old woman with palpitations and signs of atrial fibrillation and premature ventricular contractions. The third case discusses a 48-year-old man with chest pain and an extensive anterior heart attack. The fourth case involves a 55-year-old man with chest pain and signs of a major anterior heart attack.