Wolff-Parkinson-White Syndrome

Liz Johnson, RN

Definition

• WPW syndrome is the presence of accessory pathways along with the normal conduction pathways. Impulses travel thought the extra pathways as well as the normal pathways very quickly causing the heart to beat unusually fast (re-entry tachycardia).

• WPW is present at birth.

Re-entry Tachycardia

• "WPW is a form of supraventricular tachycardia

• When you have WPW, along with your normal conduction pathway, you have extra pathways called accessory pathways. They look like normal heart muscle, but they may:

• conduct impulses faster than normal • conduct impulses in both directions

• The impulses travel through the extra pathway (short cut) as well as the normal AV-HIS Purkinje system. The impulses can travel around the heart very quickly, in a circular pattern, causing the heart to beat unusually fast. This is called re-entry tachycardia.

Wolff-Parkinson-White Syndrome (WPW). 2009. Retrieved from: http://my.clevelandclinic.org June 3rd, 2009.

Symptoms

• Heart palpitations• Rapid heart rate• Dizziness• Lightheadedness• Fainting• Anxiety• Fatigue • Shortness of breath• Cardiac arrest (rare)

How WPW is Diagnosed

• Electrocardiogram

• Holter monitor/event monitor

• Exercise testing

• Electrophysiology testing

Treatment

• Medication (anti-arrhythmic)

• Ablation

• Cardioversion

• Digoxin is contraindicated in patients with WPW syndrome.

Sick Sinus Syndrome

Liz Johnson, RN

Definition

• Sick Sinus Syndrome is a type of arrhythmia caused when the sinus node (the hearts natural pacemaker) is not working properly.

• In SSS the signals from the SA node are abnormally paced, causing the heart to beat too fast, too slow, punctuated by long pauses or an alternating combination of all.

• Disease, scarring or damage to the hearts electrical system and medications can all cause the sinus node to misfire. Some medication that may set off the misfiring are:

• Calcium Channel Blockers• Beta Blockers

• Age-related wear and tear can also contribute to the sinus node dysfunction

Types of Sick Sinus Syndrome

• Sinoatrial block- electrical signals move too slowly through the sinus node, causing an abnormally slow heart rate.

• Sinus arrest- the sinus node activity pauses.

• Tachycardia-bradycardia syndrome- the heart rate alternates between abnormally fast and slow rhythms, often with a long pause between beats.

Symptoms

• Bradycardia/tachycardia/irregular heart rate• Fatigue• Dizziness• Fainting• Shortness of breath• Chest pain• Trouble sleeping• Confusion/ difficulty remembering things• Sensation of palpitations

Bradycardia-tachycardia syndrome

• Is a clinical manifestation of the sick sinus syndrome characterized by alternating periods of bradycardia and tachycardia.

How Sick Sinus Syndrome is Diagnosed

• Electrocardiogram

• Holter Monitor ECG

• Event Recorder ECG

• Electrophysiologic testing- not commonly used to diagnose SSS

Treatment

• Adjusting medications such as beta blockers and calcium channel blockers may help to relieve symptoms.

• Permanent Pacemaker insertion.

Additional treatments for a fast heart rate

• Anti-arrhythmia medications• In the case of atrial fibrillation or other abnormal

heart rhythms blood-thinning medication such as coumadin or heparin might be needed

• AV node ablation

• Radiofrequency ablation of atrial fibrillation