Sick sinus syndrome

Alternative Names

Bradycardia-tachycardia syndrome; Sinus node dysfunction

Definition of Sick sinus syndrome

Sick sinus syndrome is a collection of heart rhythm disorders that include:

Causes, incidence, and risk factors

Sick sinus syndrome is relatively uncommon. Sinus bradycardia occurs more often than the other types.


Usually, no symptoms occur. Symptoms that do occur are nonspecific and may mimic other disorders.

Signs and tests

The patient’s heart rate may be very slow at any time. Blood pressure may be normal or low.


Treatment may not be necessary if you do not have any symptoms. Your doctor may review the medicines you take to make sure they are not making your condition worse. Do not stop taking any medication unless told to do so by your doctor.

Expectations (prognosis)

The syndrome is progresssive, which means it slowly gets worse.


Issam Mikati, MD, Associate Professor of Medicine. Feinberg School of Medicine, Northwestern University, Chicago, IL. Review provided by VeriMed Healthcare Network.Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 5/4/2010

ADAM Medical Encyclopedia

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