Irregular heart rhythms - What you should know

If you notice that your heart's beating too fast or too slow, you lose consciousness, you feel faint or a little dizzy, or you notice that your heart is just not beating the way it usually does, you might have an arrhythmia – also known as a heart rhythm problem. Thomas Mattioni, MD, an independent member of the HonorHealth Medical Staff, is an electrophysiologist – a cardiologist who specializes in diagnosing and treating heart rhythms. In this Q&A, he explains what you need to know about arrhythmias — their symptoms, diagnosis and treatment. If your heart continues to beat irregularly, see your doctor.

Irregular heart rhythms - what you should know

Q. How do cardiologists diagnose arrhythmias?

A: They use an EKG (electrocardiogram also called ECG), a non-invasive test that can determine your heart rate and rhythm.

Q. What is atrial fibrillation, also known as afib?

A: Atrial fibrillation is an irregular heart rhythm that can make you feel like your heart is racing, that it's doing a flip-flop, that you're short of breath. It's the most common type of arrhythmia. Afib means that your heart's upper chambers (atria) are beating very rapidly, causing the lower chambers (ventricles) to beat irregularly.

The condition can come and go, but about half of the people who have atrial fibrillation don't even know it until it's diagnosed by an EKG.

The most serious problem with atrial fibrillation is the risk of stroke. But depending on severity, it also can lead to heart failure. Treatment for afib addresses the above risks and symptoms and includes blood-thinning medication or ablation procedures that change the heart's electrical system.

Q. What is tachycardia?

A: Tachycardia is a medical term simply meaning a fast heartbeat. Normally, the heart beats faster when you exercise or when you experience stress or illness. But when you're at rest, the heart normally beats 60 to 100 times per minute. An EKG is used to diagnosis abnormal tachycardia.

The types of tachycardia vary widely in severity. On one end of the spectrum, a tachycardia can be benign and on the other end, life-threatening, leading to cardiac arrest. Treatments vary from anti-arrhythmic drugs to ablation procedures to change the electrical properties of the heart.

Q. What is ventricular fibrillation?

A: Ventricular fibrillation is another type of tachycardia in which the lower chambers (ventricles) are racing so rapidly that they quiver and stop pumping blood normally. This condition is immediately life-threatening. Almost always, an electric shock needs to be delivered to restore normal rhythm. This is usually provided by an AED (automated external defibrillator).

As few as 5% of people who experience a ventricular fibrillation cardiac arrest outside of the hospital survive because the shock to restore the heart rhythm needs to be administered quickly. For every minute that passes, the probability of living drops by 10%. That means help needs to arrive within a few minutes. This arrhythmia is the leading cause of death in America. It almost always happens to those who have had heart attacks in the past but can also sometimes be the first evidence of a cardiac problem.

Q. What are premature beats?

A: Premature beats are extra heart beats that can occur in the upper (atrial) or lower (ventricle) chambers of the heart. If you experience a premature beat, it might feel like your heart is fluttering or skipping a beat. Everyone has premature beats, and they occur more often as you age. It can be normal to have thousands a day.

Most people can't feel their hearts beat, but for those who can, it feels like an irregularity in their chest. An EKG is used to diagnose this condition. Generally, cardiologists do not treat this condition.

Q. What is bradycardia?

A: Bradycardia is a medical term meaning a slow heart rate. This term is used for heart rates below 60 beats per minute. If you have bradycardia, you may have symptoms that include tiring easily or too quickly, and feeling dizzy or faint. An EKG can determine if you have this condition, which is usually benign.

The severity of bradycardia can vary from sick sinus syndrome — when the node that sends electrical impulses isn't working properly — to complete block in which the heart's lower chambers stop working. The most common treatment for bradycardia is a pacemaker, which restores the normal heartbeat when you're active and at rest. The pacemaker is a reliable device that has been used successfully for 50 years.

Q. What is long QT syndrome?

A: This syndrome is characterized by a rapid heartbeat that can lead to sudden fainting. In the worst cases, an erratic heartbeat caused by long QT syndrome can lead to a seizure or death. Long QT syndrome is often an inherited condition.

Many individuals who don't have any symptoms discover they have it because of an EKG or genetic testing. Doctors generally treat this condition with medications, but surgery or an implanted device may be required in more serious cases.

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If you need heart care, we've got you covered. Whether you live in the metro Phoenix area or you're looking to travel to HonorHealth from another part of the state or country, you'll receive in-depth care designed with your convenience in mind.

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