Mediastinum & superficial anatomy of the heart pt.2 Flashcards
The____________________ lies between the brachiocephalic trunk and right brachiocephalic
vein.
Right vagus nerve
How does the right vagus nerve descend?
Descends posteriorly towards trachea and crosses the lateral surface of the trachea passing posterior to the oesophagus.
List the branches of the right vagus nerve
Cardiac plexus
Pulmonary plexus
Oesophageal plexus
Which nerve lies posterior to the left brachiocephalic vein, between left common
carotid and left subclavian arteries?
Left vagus nerve
Describe the course of the left vagus nerve
Lies deep to parietal pleura, crosses left side of arch of aorta, passing posterior to root of the left lung.
List the branches of the left vagus nerve
Cardiac plexus
Pulmonary plexus
Oesophageal plexus
Name the branch of the left vagus nerve
Left recurrent laryngeal nerve
Where does the left recurrent laryngeal nerve arise?
At the inferior margin of the aortic arch, lies lateral to ligamentum arteriosum
Passes inferior to arch of aorta, entering groove between trachea and oesophagus.
Describe the right phrenic nerve
Enters mediastinum lateral to vagus nerve.
Lies posterolateral to the right brachiocephalic vein and continues along right side of SVC.
Descends along right side of pericardial sac within the fibrous pericardium, anterior to the root of the right lung.
The right phrenic nerve passes through the diaphragm at the______________________
Caval opening
Describe the left phrenic nerve
Enters mediastinum lateral to the left vagus nerve.
Lies posterolateral to the left brachiocephalic vein.
Passes superficially to the left vagus nerve and left superior intercostal vein.
Follows the left side of the pericardial sac and lies anterior to the root of the left lung.
Where does the left phrenic nerve pierce the diaphragm?
Near the apex of the heart
Name the layers of the pericardium
Fibrous pericardium
Serous pericardium (divided into visceral and parietal percardium)
What is the space between the two layers of the serous pericardium?
pericardial cavity
Describe the fibrous pericardium
Tough connective tissue outer layer.
Cone-shaped bag, apex is continuous with adventitia of great vessels
How is the heart able to retain its position in the mediastinum, and limit distention?
It retains its position due to the attachment of its base to the central tendon of the diaphragm, and its attachment to the sternum via the sternopericardial ligaments
The pericardial sac helps limit cardiac distention
What innervates the fibrous pericardium?
Phrenic nerves pass through and innervate fibrous pericardium, with pericardiophrenic vessels.
What is the importance of the serous fluid?
Allows for uninhibited movement of the heart
T/F: The parietal layer is continuous with the visceral layer at the apex of the heart
F
Parietal layer continuous with visceral layer around roots of great
vessels.
T/F: Parietal layer lines the fibrous pericardium. Visceral layer is adherent to the heart.
T
Describe the superior and posterior reflections of the serous pericardium
Superiorly – surrounds aorta and pulmonary trunk.
Posteriorly – surrounding veins (IVC and Pulmonary veins)
What is another name for the cul-de-sac (zone of relfection around veins?
Oblique pericardial sinus
What is the passage between the two zones of relfection, and where does it lie?
TRANSVERSE PERICARDIAL SINUS
Lies posterior to ascending aorta and pulmonary trunk
Anterior to superior vena cava
Superior to left atrium
List the arterial supply of the pericardium
Internal thoracic artery
Pericardiophrenic, Musculophrenic and Inferior phrenic arteries
Thoracic aorta