Cardiology Question:

Kussmaul's sign is the observation of a jugular venous
pressure (JVP, the filling of the jugular vein) that rises
with inspiration. It can be seen in some forms of heart
disease.
Ordinarily the JVP falls with inspiration due to
reduced pressure in the expanding thoracic cavity.
Kussmaul's sign suggests impaired filling of the right
ventricle due to either fluid in the pericardial space or a
poorly compliant myocardium or pericardium.