UMEM Educational Pearls

Category: Cardiology

Title: Sick Sinus Syndrome

Keywords: Sick Sinus Syndrome (PubMed Search)

Posted: 8/31/2014 by Semhar Tewelde, MD
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Sick Sinus Syndrome

- Sick sinus syndrome (SSS) is a cardiac conduction disorder characterized by symptomatic dysfunction of the sinoatrial (SA) node.

- SSS usually manifests as sinus bradycardia, sinus arrest, or sinoatrial block, and is sometimes accompanied by supraventricular tachydysrhythmias.

- Symptoms of SSS include: syncope, dizziness, palpitations, exertional dyspnea, fatigability from chronotropic incompetence, heart failure, and angina.

- Clinically significant SSS typically requires pacemaker implantation. Approximately 30% to 50% of pacemaker implantation in the United States list SSS as the primary indication.

- 2 large, prospective cohorts with an average follow-up of 17 years, observed the incidence of SSS increases with age, does not differ between men and women, and is lower among blacks than whites.

- Risk factors for SSS included greater BMI & height, elevated NT-proBNP level & cystatin C level, longer QRS interval, lower heart rate, hypertension, and right bundle branch block.

References

Jensen P, Gronroos N, et al. Incidence of and Risk Factors for Sick Sinus Syndrome in the General Population. Journal of the American College of Cardiology. Vol 64 Issue 6, pages 531-538