Cracking the Code
Sick sinus syndrome (SSS) is a disorder of the heart’s natural pacemaker. Typically, SSS is treated with an implanted pacemaker. A pacemaker consists of a small, battery-powered generator and one or more leads. With a single-chamber system, only one lead is used. With a double-chamber system, two leads are used and placed in the right atrium and right ventricle.
CPT Assistant, June 2012 pages 3-9: Pacemaker and pacing cardioverter-defibrillator reporting