Arrhythmia is any variation from the normal rhythm of the heartbeat. The heart rate at rest is usually between 60 and 100 beats per minute. Much lower rates may be normal in young adults, particularly those who are physically fit. Variations in heart rate are normal. The heart rate responds not only to exercise and inactivity but also to such factors as pain and anger.
When the heart rate is too fast or too slow or when the electrical impulses travel in abnormal pathways is the heartbeat considered abnormal. Such rhythms may be regular or irregular.
How a patient describes his or her arrhythmia symptoms often helps the doctor diagnose an arrhythmia and determine how serious it is. The most important considerations are whether the:
- Heartbeats are fast or slow, regular or irregular and short or long
- Person feels dizzy, light-headed, faint or even loses consciousness
- Person is experiencing chest pain, shortness of breath or other unusual sensations along with the palpitations
- Palpitations happen when the patient is at rest or only during strenuous or unusual activity
- Palpitations start and stop suddenly or gradually
Techniques for finding the exact nature of arrhythmia include:
- Electrocardiography (EKG) is the primary test for detecting arrhythmias. This test can provide a picture of the arrhythmia. An EKG shows the heart rhythm over a brief time. Often, however, arrhythmias come and go.
- A portable monitor (Holter monitor) that the patient wears for 24 hours can record arrhythmias that may occur during a normal day. The patient is also asked to keep a diary of symptoms while the monitor is worn.
- Electrophysiologic studies may be helpful when long-term, life-threatening arrhythmia is suspected.
Several procedures can be useful in correcting irregular heart rhythms:
- Radiofrequency ablation in which electrical energy is applied to eliminate abnormal electrical pathways in the heart and restore normal heart rhythms.
- MAZE, a new surgical technique that can permanently end atrial fibrillation