"Sick sinus syndrome" is an anthropomorphic term. Sickness relates to a person, not an organ or tissue. A component part of the human body can become inflamed, degenerated, hypertrophic, or atrophic, but never sick. Still, despite its inappropriateness, the term has survived 13 years of use since Irene Ferrer1 introduced it in 1967. Perhaps it is just as well. The disease complex itself is too loosely defined to permit a more accurate label. "Sick sinus" may be anatomically inaccurate as well. Kaplan and associates2 demonstrated lesions in the extranodal atrial tissue and junctional tissue, as well as the sinus in patients with typical clinical manifestations of the syndrome. Moreover, clinical findings are not always characteristic. The classic tachyarrhythmia-bradyarrhythmia sequence may not be present. Severe bradycardia without any other sinus dysfunction has been also subsumed under this syndrome.3
Drug therapy of the sick sinus may be perplexingly difficult.
Vaisrub S. The Not-So-Sick Sinus. JAMA. 1980;243(20):2068. doi:10.1001/jama.1980.03300460050031