The term "sulcus terminalis" refers to a groove on the tongue. In IPA phonetic transcription, it is spelled /ˈsʌlkəs tərˈmɪnəlɪs/. The first syllable is pronounced with a short "u" sound and the "s" sound at the beginning is unvoiced. The second syllable includes the "er" sound before the stressed syllable "mi." The last syllable includes the short "i" sound and an unstressed "u" sound. Overall, the word is pronounced with a stress on the second syllable.
The sulcus terminalis is a anatomical feature found in the heart, particularly the right atrium. It is a ridge-like structure that separates the smooth regions from the rough regions of the atrium. The term "sulcus terminalis" originates from Latin, where "sulcus" means a groove or furrow, and "terminalis" refers to something that marks a boundary or limit.
In the heart, the sulcus terminalis runs along the inner surface of the right atrium, separating the posterior region (sinus venarum) from the anterior region (right atrial appendage). It begins near the superior vena cava and extends towards the inferior vena cava, curving around the border of the atrium. The sulcus terminalis is characterized by its prominent appearance, appearing as a muscular ridge.
This anatomical structure is of significance due to its role in heart electrical signaling. It serves as the boundary between two different types of cardiac muscle cells. The smooth posterior region contains pacemaker cells, responsible for initiating and regulating the heart's rhythm, while the rough anterior region contains contractile myocardial cells. The distinct boundary created by the sulcus terminalis helps to ensure proper coordination of electrical impulses within the heart.
The sulcus terminalis is an essential landmark for clinicians performing cardiac procedures or imaging the heart, as it aids in identifying the anatomical structures within the right atrium. Its presence and appearance serve as important indicators of a healthy heart function.
(1) A V-shaped groove, with apex pointing backward, on the surface of the tongue, marking the separation between the oral, or horizontal, and the pharyngeal, or vertical, parts of this organ; (2) a groove on the surface of the right atrium of the heart, marking the junction of the primitive sinus venosus with the atrium.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.
The word sulcus terminalis originates from Latin. Specifically, sulcus means furrow or groove, while terminalis means terminal or end.