Acute flare-up of heart failure

A sudden (acute) episode of heart failure is most often the result of heart function that gets worse. You may become much more short of breath, have much more fluid buildup (edema) than usual, and find that your ability to exert yourself is significantly reduced. If the episode is very severe, you may also develop symptoms of low cardiac output such as lightheadedness, profound fatigue, or decreased urine output. What sets an acute flare-up apart from the expected gradual worsening of your heart failure over time is that the change in symptoms occurs over a very short time.

Acute episodes of heart failure are very common and are one of the most common causes of admission to the hospital. What happens after one of these flare-ups depends on the cause. It is likely that your heart failure symptoms will return to their prior baseline once the cause is treated if it was caused by a temporary situation such as a high-salt meal, forgetting your medicines, or developing an irregular heartbeat (specifically, atrial fibrillation), anemia, an infection, or a fever.