THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The SA node, also known as the sinus node, represents a crescent-like shaped cluster of myocytes divided by connective tissue, spreading over a few square millimeters. It is located at the junction of the crista terminalis in the upper wall of the right atrium and the opening of the superior vena cava.

Detailed explanation-2: -An electrical stimulus is generated by the sinus node (also called the sinoatrial node, or SA node). This is a small mass of specialized tissue located in the right upper chamber (atria) of the heart. The sinus node generates an electrical stimulus regularly, 60 to 100 times per minute under normal conditions.

Detailed explanation-3: -Sinoatrial node It sends the electrical impulses that start the heartbeat. The SA node is in the upper part of your heart’s right atrium. It is at the edge of your atrium near your superior vena cava (vein that brings oxygen-poor blood from your body to your heart).

Detailed explanation-4: -The sinoatrial node is located in the upper part of the right atrium in the healthy heart, and serves as the natural pacemaker (Figure 1).