Question
Pain arising from the parietal pericardium is transmitted through which of the following nerves?
| A. | Cardiac plexus |
| B. |
Greater splanchnic nerve |
| C. |
Intercostal nerve |
| D. |
Phrenic nerve |
Show Answer
|
Correct Answer » D Explanation |
 |
The parietal pericardium is supplied by the phrenic nerve (C3, C4, C5), which carries somatic sensory fibers. Inflammation of the parietal pericardium (e.g., acute pericarditis) produces sharp, well-localized pain that is transmitted through the phrenic nerve.
Because the phrenic nerve originates from C3–C5 spinal segments, pain is often referred to the shoulder and supraclavicular region, especially the left shoulder.
Explanation of Each Option
A. Cardiac plexus
- The cardiac plexus contains autonomic (sympathetic and parasympathetic) fibers supplying the heart.
- It is not responsible for transmitting pain from the parietal pericardium.
B. Greater splanchnic nerve.
- The greater splanchnic nerve supplies abdominal viscera such as the stomach, liver, pancreas, and upper gastrointestinal tract.
- It has no role in sensory innervation of the pericardium.
C. Intercostal nerve
- Intercostal nerves supply the thoracic wall and the peripheral part of the diaphragmatic pleura and diaphragm.
- They do not supply the fibrous or parietal pericardium.
D. Phrenic nerve
- Provides sensory innervationto:
- Fibrous pericardium
- Parietal layer of the serous pericardium
- Central diaphragmatic pleura
- Central diaphragmatic peritoneum
- Pain is referred to the C3–C5 dermatomes (shoulder region).
