Congestive heart failure occurs when the heart cannot pump enough blood to the body. It can be caused by conditions like high blood pressure, coronary artery disease, and viral infections. Common symptoms include shortness of breath, swelling of the legs and abdomen, fatigue, cough, reduced urine production, and arrhythmias. Without treatment, the symptoms worsen over time and advanced CHF can be fatal due to sudden cardiac arrest from arrhythmias.