The prognosis for atrial flutter is generally positive if the patient seeks treatment, according to WebMD. This is because atrial flutter in itself is not life threatening, explains the Heart Rhythm Society.
If atrial flutter affects a person who has no heart disease, the prognosis is generally quite good, notes WebMD. If the patient has an underlying heart disease or lung disease, however, atrial flutter may recur, and it may get worse even with treatment, adds MedlinePlus.
If left untreated, the complications from atrial flutter could be life threatening, according to the Heart Rhythm Society. This is because the condition makes it harder for the heart to pump blood effectively.
When the heart does not pump blood properly, blood moves slowly and is more likely to clot, according to WebMD. Clots may break away and travel to the brain where they could block a blood vessel and cause a stroke or a heart attack.
When left untreated, atrial flutter could weaken the heart muscles over time and result in a condition known as cardiomyopathy, reports the Heart Rhythm Society. This may cause heart failure and long-term disability. This condition could also lead to a different type of arrhythmia known as atrial fibrillation.