Sick sinus syndrome

Sick sinus syndrome
Sick sinus syndrome
ICD-10	I49.5
ICD-9	427.81
OMIM	163800
DiseasesDB	12066
MedlinePlus	000161
eMedicine	med/2132

WikiDoc Resources for Sick sinus syndrome
Articles
Most recent articles on Sick sinus syndrome Most cited articles on Sick sinus syndrome Review articles on Sick sinus syndrome Articles on Sick sinus syndrome in N Eng J Med, Lancet, BMJ
Media
Powerpoint slides on Sick sinus syndrome Images of Sick sinus syndrome Photos of Sick sinus syndrome Podcasts & MP3s on Sick sinus syndrome Videos on Sick sinus syndrome
Evidence Based Medicine
Cochrane Collaboration on Sick sinus syndrome Bandolier on Sick sinus syndrome TRIP on Sick sinus syndrome
Clinical Trials
Ongoing Trials on Sick sinus syndrome at Clinical Trials.gov Trial results on Sick sinus syndrome Clinical Trials on Sick sinus syndrome at Google
Guidelines / Policies / Govt
US National Guidelines Clearinghouse on Sick sinus syndrome NICE Guidance on Sick sinus syndrome NHS PRODIGY Guidance FDA on Sick sinus syndrome CDC on Sick sinus syndrome
Books
Books on Sick sinus syndrome
News
Sick sinus syndrome in the news Be alerted to news on Sick sinus syndrome News trends on Sick sinus syndrome
Commentary
Blogs on Sick sinus syndrome
Definitions
Definitions of Sick sinus syndrome
Patient Resources / Community
Patient resources on Sick sinus syndrome Discussion groups on Sick sinus syndrome Patient Handouts on Sick sinus syndrome Directions to Hospitals Treating Sick sinus syndrome Risk calculators and risk factors for Sick sinus syndrome
Healthcare Provider Resources
Symptoms of Sick sinus syndrome Causes & Risk Factors for Sick sinus syndrome Diagnostic studies for Sick sinus syndrome Treatment of Sick sinus syndrome
Continuing Medical Education (CME)
CME Programs on Sick sinus syndrome
International
Sick sinus syndrome en Espanol Sick sinus syndrome en Francais
Business
Sick sinus syndrome in the Marketplace Patents on Sick sinus syndrome
Experimental / Informatics
List of terms related to Sick sinus syndrome

Cardiology Network
Discuss Sick sinus syndrome further in the WikiDoc Cardiology Network
Adult Congenital
Biomarkers
Cardiac Rehabilitation
Congestive Heart Failure
CT Angiography
Echocardiography
Electrophysiology
Cardiology General
Genetics
Health Economics
Hypertension
Interventional Cardiology
MRI
Nuclear Cardiology
Peripheral Arterial Disease
Prevention
Public Policy
Pulmonary Embolism
Stable Angina
Valvular Heart Disease
Vascular Medicine

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [2] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.

Key words and synonyms: Bradycardia-tachycardia syndrome, tachycardia-bradycardia syndrome, tachy-brady syndrome.

Overview

Sick sinus syndrome, also called Sinus node dysfunction, is a group of abnormal heart rhythms (arrhythmias) presumably caused by a malfunction of the sinus node, the heart's "natural" pacemaker. Bradycardia-tachycardia syndrome is a variant of sick sinus syndrome where atrial flutter and fibrillation alternate with prolonged periods of asystole.

Common Causes

Sick sinus syndrome can result in many abnormal heart rhythms (arrhythmias), including sinus arrest, sinus node exit block, sinus bradycardia, and other types of bradycardia (slow heart rate).

Sick sinus syndrome may also be associated with tachycardias (fast heart rate) such as paroxysmal supraventricular tachycardia (PSVT) and atrial fibrillation. Tachycardias that occur with sick sinus syndrome are characterized by a long pause after the tachycardia.

Abnormal rhythms are often caused or worsened by medications such as digitalis, calcium channel blockers, beta-blockers, sympatholytic medications, and anti-arrhythmics. Disorders that cause scarring, degeneration, or damage to the conduction system can cause sick sinus syndrome, including sarcoidosis, amyloidosis, Chagas' disease, and cardiomyopathies.

Sick sinus syndrome is more common in elderly adults, where the cause is often a non-specific, scar-like degeneration of the cardiac conduction system. Cardiac surgery, especially to the atria, is a common cause of sick sinus syndrome in children.

Coronary artery disease, high blood pressure, and aortic and mitral valve diseases may be associated with sick sinus syndrome, although this association may only be incidental.

Symptoms

Even though many types of sick sinus syndrome produce no symptoms, patients may present with:

• Stokes-Adams attacks - fainting due to asystole or ventricular fibrillation
• Dizziness or light-headedness
• Palpitations
• Chest pain or angina
• Shortness of breath
• Fatigue
• Headache

Diagnosis

Ambulatory monitoring of the electrocardiogram (ECG) may be necessary because arrhythmias are transient. The ECG may show any of the following

• Inappropriate sinus bradycardia
• Sinus arrest
• Sinoatrial block
• Atrial fibrillation with slow ventricular response
• A prolonged asystolic period after a period of tachycardias
• Atrial flutter
• Ectopic atrial tachycardia
• Sinus node reentrant tachycardia

Electrophysiologic tests are no longer used for diagnostic purposes because of their low specificity and sensitivity. Cardioinhibitory and vasodepressor forms of sick sinus syndrome may be revealed by tilt table testing.

• Sick Sinus Syndrome

  Sick Sinus Syndrome

Treatment

Bradyarrhythmias are well controlled with pacemakers, while tachyarrhythmias respond well to medical therapy. However, because both bradyarrhythmias and tachyarrhythmias may be present, drugs to control tachyarrhythmia may exacerbate bradyarrhythmia. Therefore, a pacemaker is implanted before drug therapy is begun for the tachyarrhythmia.

ACC / AHA Guidelines- Recommendations for Permanent Pacing in Sinus Node Dysfunction (DO NOT EDIT)

“

Class I 1. Permanent pacemaker implantation is indicated for SND with documented symptomatic bradycardia, including frequent sinus pauses that produce symptoms. (Level of Evidence: C) 2. Permanent pacemaker implantation is indicated for symptomatic chronotropic incompetence. (Level of Evidence: C) 3. Permanent pacemaker implantation is indicated for symptomatic sinus bradycardia that results from required drug therapy for medical conditions. (Level of Evidence: C) Class IIa 1. Permanent pacemaker implantation is reasonable for SND with heart rate less than 40 bpm when a clear association between significant symptoms consistent with bradycardia and the actual presence of bradycardia has not been documented. (Level of Evidence: C) 2. Permanent pacemaker implantation is reasonable for syncope of unexplained origin when clinically significant abnormalities of sinus node function are discovered or provoked in electrophysiological studies. (Level of Evidence: C) Class IIb 1. Permanent pacemaker implantation may be considered in minimally symptomatic patients with chronic heart rate less than 40 bpm while awake. (Level of Evidence: C) Class III 1. Permanent pacemaker implantation is not indicated for SND in asymptomatic patients. (Level of Evidence: C) 2. Permanent pacemaker implantation is not indicated for SND in patients for whom the symptoms suggestive of bradycardia have been clearly documented to occur in the absence of bradycardia. (Level of Evidence: C) 3. Permanent pacemaker implantation is not indicated for SND with symptomatic bradycardia due to nonessential drug therapy. (Level of Evidence: C)

”

See Also

• The CHF Living Guidelines: Vote on current recommendations and suggest revisions to the guidelines

Sources

• The ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities

External links

• NIH website
• eMedicine Page

References

• Adan V, Crown LA (2003). "Diagnosis and treatment of sick sinus syndrome". Am Fam Physician. 67 (8): 1725–32. PMID 12725451.

Template:WikiDoc Sources