What causes irregular heartbeats?

There are many possible causes of irregular heartbeats (or arrhythmias), and it can sometimes be difficult to pinpoint the precise cause. However, some common causes include interstitial cystitis, atrial fibrillation, and Wolff-Parkinson-White Syndrome. In addition, smokers and heavy drinkers are also at increased risk for developing irregular heartbeats. Treatment for arrhythmias will generally depend on the underlying cause but may involve medication, pacemakers/implanted cardioverter defibrillators, or surgery.