Traube's sign is a symptom named after the German physician Ludwig Traube (1818-1876).
It is characterized by rhythmic fluctuations in blood pressure and heart rate synchronized with breathing. This symptom is observed with cardiac tamponade, constrictive pericarditis, as well as with some other conditions accompanied by increased intrathoracic pressure.
The mechanism for the development of Traube's symptom is that during inspiration, negative pressure in the pleural cavity leads to a decrease in venous return to the right side of the heart. This causes a decrease in cardiac output and a decrease in blood pressure. During exhalation, the reverse process occurs - venous return increases, cardiac output increases and blood pressure rises.
Thus, Traube's symptom is an important diagnostic sign of increased pressure in the pericardial cavity. Its identification requires additional research to clarify the cause.