DEAR DR. ROACH: At age 76, I was diagnosed with sinus node dysfunction last year after several episodes of what I’d call being “spaced out” (for lack of a better term). I couldn’t explain these ...

Lymph nodes are located at the junction of lymphatic vessels in the body. Lymphatic vessels transport fluid containing antigenic material, dendritic cells (DCs), and inflammatory biochemicals from ...

Sick sinus syndrome (SSS) is the name that doctors use to refer to heart rhythm problems. These occur when the sinus node, the heart’s natural pacemaker, does not keep a regular heartbeat. This heart ...

Recent studies have identified cortical sinuses as sites of sphingosine-1-phosphate receptor-1 (S1P₁)-dependent T- and B-cell egress from the lymph node (LN) parenchyma. However, the distribution of ...

A sinus arrhythmia refers to a problem with the sinus node of the heart. This controls the rhythm of the heart and can be fast (sinus tachycardia) or slow (sinus bradycardia). This article looks at ...

Sinus rhythm is the term for the regular pattern of heartbeats driven by the heart’s natural pacemaker, the sinus node. Variations like sinus tachycardia (fast heart rate) and sinus bradycardia (slow ...

Sinus tachycardia is the most common and often neglected rhythm disturbance encountered in clinical practice. Whether appropriate or not, it is often associated with troublesome symptoms, and ...