Adult Echocardiography Practice Exam

Less than 50% reduction in diameter of a dilated IVC with inspiration is indicative of:

1. IVC integra

2. IVC decompensation

3. IVC decompression

4. IVC plethora

The correct answer is: IVC plethora

A less than 50% reduction in the diameter of the inferior vena cava (IVC) during inspired breathing is indicative of IVC plethora. This occurs when the volume of blood returning to the heart via the IVC is increased, often due to factors such as right heart failure, fluid overload, or other conditions that lead to elevated central venous pressure. In a healthy individual, the IVC should collapse significantly with inspiration due to the negative intrathoracic pressure that is created, which enhances venous return. If the IVC fails to exhibit significant collapse, as seen in cases of IVC plethora, it suggests that there is too much blood in the venous system, resulting in the inability of the IVC to decrease in size effectively. In contrast, conditions like IVC decompensation or IVC decompression typically involve significant collapse of the IVC, while IVC integra refers to a normal IVC response during respiration. Hence, the failure of adequate reduction in the IVC diameter more than highlights the presence of volume overload or poor response to physiological changes in the thoracic cavity.