Kussmaul’s sign is classically seen in: (A) Infective endocarditis, (B) Malignant hypertension, (C) Constrictive pericarditis, (D) Patent ductus arteriosus
Answer is C. Normally, the venous pressure should fall by at least 3 mmHg with inspiration. Kussmaul's sign is defined by either a rise or a lack of fall of the JVP with inspiration and is classically associated with constrictive pericarditis, although it has been reported in patients with restrictive cardiomyopathy, massive pulmonary embolism, right ventricular infarction and advanced left ventricular systolic heart failure.