**Question:** A 70-year-old male presented to the OPD with complaints of abdominal pain, nausea, headache, malaise, persistent fever for 2 weeks along with constipation. On examination a characteristic rash was observed on the trunk and chest. BP - 120/70 mm of Hg HR- 65 bpm Hepatomegaly Splenomegaly Blood culture did not show any organism, hence a bone marrow culture was taken. Gram staining was done. Which of the following pulses will be most likely seen in the above condition: -

A. Pulsus paradoxus (Pulsus paradoxus is the transient increase in pulse amplitude during inspiration, typically seen in constrictive pericarditis or constrictive cardiomyopathy.)
B. Pulsus quaternus (Pulsus quaternus is a clinical sign characterized by four beats per respiratory cycle and is seen in constrictive pericarditis or constrictive cardiomyopathy.)
C. Pulsus ternus (Pulsus ternus is a clinical sign characterized by three beats per respiratory cycle and is seen in constrictive pericarditis or constrictive cardiomyopathy.)
D. Pulsus bispex (Pulsus bispex is a clinical sign characterized by two beats per respiratory cycle and is seen in constrictive pericarditis or constrictive cardiomyopathy.)

**Correct Answer:** D. Pulsus bispex (Pulsus bispex is a clinical sign characterized by two beats per respiratory cycle and is seen in constrictive pericarditis or constrictive cardiomyopathy.)

**Explanation:**

In the presented case, the patient exhibits symptoms and signs of a potentially life-threatening condition called constrictive pericarditis or constrictive cardiomyopathy. These conditions are characterized by the constriction of the pericardium and heart chambers, respectively.

The correct answer, Pulsus bispex, refers to the clinical sign that manifests as two beats per respiratory cycle. This sign is indicative of constrictive pericarditis or constrictive cardiomyopathy, as the constrictive nature of the mentioned conditions leads to a decrease in the heart chambers' filling during inspiration, resulting in a two-to-one relationship between heartbeats and respiratory cycles.

**Core Concept:**

Constrictive pericarditis and constrictive cardiomyopathy are conditions characterized by the constriction of the pericardium and heart chambers, respectively. These conditions affect the normal filling and emptying of the heart chambers during respiration, leading to abnormal heart sounds and clinical signs like Pulsus bispex.

**Why the Other Options are Incorrect:**

A. Pulsus paradoxus: This sign refers to an increase in heart rate during inspiration, which is not relevant to the presented case as the patient exhibits a two-to-one relationship between heartbeats and respiratory cycles.

B. Pulsus quaternus: This sign refers to four beats per respiratory cycle, which is not consistent with the patient's clinical presentation.

C. Pulsus triads: Pulsus triads are a set of three clinical signs (m