In-Depth
Heart arrhythmias
Symptoms
- Symptom Checker Use this Symptom Checker to pinpoint possible causes of your medical symptoms.
- Vasovagal syncope Vasovagal syncope — Comprehensive overview covers symptoms, treatment of sudden, brief loss of consciousness.
Tests and diagnosis
- Tilt table test Tilt table test — Overview covers definition, what to expect and results of this test.
- Stress test A stress test — Overview covers what to expect and results of this heart test.
- Holter monitor Holter monitor — Overview covers what to expect during this test of your heart rhythm.
- Electrocardiogram (ECG or EKG) Electrocardiogram (ECG or EKG) — Overview covers definition of this test to monitor your heartbeat.
Causes
- Long QT syndrome Long QT syndrome — Comprehensive overview covers causes and treatment of this racing heart condition.
- Hyperthyroidism (overactive thyroid) Hyperthyroidism — Comprehensive overview covers symptoms, causes, treatment of an overactive thyroid gland.
Treatments and drugs
- Cardioversion Cardioversion — Overview covers what to expect during this procedure to reset your heart's rhythm.
- Cardiac ablation Cardiac ablation — Overview covers risks, results of this surgery to correct heart rhythm problems.
- Pacemaker Pacemaker — Overview covers risks, results of the procedure to install this heartbeat-regulating device.
- Implantable cardioverter-defibrillators (ICDs) Implantable cardioverter-defibrillators (ICDs) — Overview covers the definition and risks of implanting these devices.
Prevention
- Automated external defibrillators: Do you need an AED? Automated external defibrillators are available without a prescription. Should you get one?


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