A feeling of shortness of breath, which doctors call dyspnea, frequently happens during arrhythmias. This symptom can be very difficult for people to describe and may be referred to as:

• Shortness of breath.
• Tightness in the chest.
• Being winded.
• Feeling tired from walking.

What causes shortness of breath?

When an arrhythmia causes the heart to beat too fast, the heart does not pump effectively. Specifically, there may not be enough time between heartbeats for the heart to fill with blood, causing blood to back up into the lungs. The increased pressure and fluid in the lungs results in the feeling of shortness of breath.