Superior Vena Cava Syndrome (SVCS) is a medical condition in which the superior vena cava, a major vein transporting deoxygenated blood from the upper body to the heart, becomes obstructed or compressed. SVCS can result from various causes, such as tumors, blood clots, or inflammation. In medical terminology, there are no direct synonyms for SVCS, as it is a specific condition with unique characteristics. However, it is sometimes referred to as Superior Vena Cava Obstruction or Superior Vena Cava Compression. Although these terms do not truly replace SVCS, they are used interchangeably to describe the obstruction or compression of the superior vena cava, leading to similar symptoms and complications.