Anatomy - Cardiovascular Theory Flashcards
Which nerev sits anterior to the hilum of the lung?
Phrenic
(Phrenic in front)
Which nerve sits posterior to the hilum of the lung?
Vagus nerve
Where do the phrenic nerve lie in relation to the pericardium?
To the lateral borders
Which two main layers is the pericardium split?
- Fibrous
- Serous
The serous pericardium is subdivided into which two parts?
- Visceral - attaches directly to the heart
- Parietal
The visceral serous pericardium is known by which other name?
Epicardium
Increased pericardial fluid can cause which condition?
Cardiac tamponade
What is it called if blood is in the pericardial space?
Haemopericardium
What is a pericardiocentesis?
The process to remove fluid from the pericardial cavity
The needle is inserted at the infrasteral angle and directed posteriorly
What is the space called posterior to the ascending aorta and pulmonary trunk?
Transverse pericardial sinus
What are the three heart surfaces?
- Anterior (sternocostal)
- Base (posterior) - left atrium
- Inferior (diaphragmatic)
What are the 4 heart borders?
- Right
- Left
- Inferior - lies on diaphragm
- Superior - great vessels
Where is the apex beat normally palpated?
5th intercostal space - mid-clavicular line
The heart is present in the ________ medistinum
Middle
What are the heart auricles?
Extensions of the atria
Where does the right coronary artery run?
The right atrial ventricular groove
Where does the left coronary artery run?
Anterior interventricular groove - between the two ventricles
The posterior interventricular artery is a branch of which coronary artery?
Right
Which two coronary vessels lie in the posterior interventricular groove?
- Posterior interventricular artery
- Posterior interventricular vein
Which coronary vessel collects deoxygenated blood and drians directly into the right atrium?
Coronary sinus
The left coronary artery is often known by which other name?
Anterior interventicular artery
What are the frst branches to come off of the aorta?
Coronary arteries
There is an anstomosis between left and right coronary arteries
True or False?
True
The right coronary artery splits into which two main arteries?
- Right marginal artery
- Posterior interventricular artery
The left coronary artery splits into which two main arteries?
- Left anterior descending artery
- Circumflex artery
Name the main branch off of the circumflex artery
Left marginal artery
Name the main branch off of the left anterior descending artery
Lateral (diagonal) branch
What are the two parts to the septum?
- Interatrial septum - located at the interatrial groove
- Interventricular septum - located at the anterior interventricular groove
Any septal defect may allow for what?
Mixing of blood
(deoxygenated wth oxygenated)
What is Eisenmenger’s syndrome?
There is a left to right cardiac shunt due to higher left sided pressure
This occurs long term and results in pulonary hypertension leading to damage to lung capillaries leading them to be replaced with scar tissue
Lung function decreases - scar tissue reduces lung compliance, additional blood volume
Over time, right ventricular hypertrophy occurs until right pressure exceeds the left and a right to left cardiac shunt occurs
Systemic circulation is not adequately oxygenated, an O2 saturation decreases leadign to cyanosis and organ damage
What are the tricuspid and mitral valvaes composed of?
- Valve leaflets
- Tendinous chords
- Papillary muscles
What are semi-lunar valves?
Aortic and pulmonary
What are semi-lunar valves compsoed of?
3 pockets which can open up and occlude the artery preventing backflow
(similar to a Lucozade bottle top)
What is the moderator band?
Septomarginal trabecula
Muscular band of tissue in the right artrium that can carry part of the AV bundle to the papillary muscle of the anterior cusp
What is the name of the border between the atrial and auricle walls?
Crista terminalis
In the left atrium remain of what embryological structure may still be present?
Foramen ovale
What are the three nerve systems of the heart?
- Autonomic innervation - sympathetic/parasympathetic
- Visceral afferents - sensory
- Conducting system of the heart
Presynaptic fibres to the heart exit the spinal cord via what?
Spinal nerves
Spinal nerves can only exit the spinal cord in which region?
T1-L2/3 (thoracolumbar region)
When the spinal nerve exits the spinal cord, what 5 options is it now presented with?
- Synpse with the ganglion at the level it exits
- Ascend superiorly to synapse with a superior ganglion
- Descend inferiorly and synapse with an inferior ganglion
- Become an abdominopelvic splanchnic nerve
- Pass through the symapthetic chain and syanpse at the adrenal medulla (without synpasing as an abdominopelvic nerve)
What happens when a spinal nerve passes through the sympathetic chain and becomes and abdomiopelvic splanchinic nerve?
It will instead synapse at a prevertebral ganglion of the abdomen
How do post synaptic sympathetic nerves get to the heart and lungs?
Cardiopulmonary splanchnic nerves from:
- T1-T5 ganglia
- Cervicl ganglia
What is the cardiac plexus?
An intertwining of nerves associated with the heart
- Sympathetic fibres - from cardiopulmonary splanchnic nerves
- Parasympathetic fibres - from vagus nerve
- Visceral afferent fibres
What is the main difference between parasympathetic and sympathetic ganglia?
Parasymapthetic ganglia are not found in chain and instead are found around the body
All of the parasympathetic signals are transmitted by which 4 cranial nerves?
- CN III - oculomotor
- CN VII - facial
- CN IX - glosspharyngeal
- CN X - vagus
Why is heart rate kept low?
There is constant vagal tone
Baroreceptors in the aortic arch send impulses in reflex afferent via which nerve?
Vagus nerve
What are the two main sources of chest pain?
- Somatic - muscular, joint, bone fibrous pericardial, nervous
- Visceral - heart and great vessels, trachea, oesophagus, abdominal viscerae
Somatic pain has what type of pain?
Stabbing, localised
Which type of pain is dull, aching, nauseating and poorly localised?
Visceral
What is radiating pain?
Pain is felt at the actual site of injury
Pain in the centre of the chest spreading outwards to other locations
What is referred pain?
Pain felt at a site away from tissue damage
Which receptors will send an impusle in the presence of pain?
Mechanoreceptors
In which area of the brain is somatic pain felt?
Post central gyrus of parietal lobe - somatosensory region
What is the role of the precentral gyrus in relation to pain?
It is a somatomotor region
APs originating here bring about contraction of skeletal muscle in the body wall
Dull visceral central chest pain may be caused by?
- Tracheitis
- Ruptured aneurysm of aortic arch
- Abdominal viscerae stimulation
- Oesophagitis
- Angina and MI
Which two main sections is the mediastinu split into?
- Superior
- Inferior (anterior, middle, posterior)
Which nerve will be found at the right lateral border of the trachea?
Vagus
Why does the azygous vein change directionand were does it do this?
To drain into SVC
Superior to the right lung hilum
What is the ligamentum arteriosum?
A remnant of the embylogical structure - the ductus arteriosus
It now joins the pulmonary trunk to the arch of the aorta
The left vagus nerve cross which major vessle to form a plexus on the oesophagus?
Aortic arch
Where do visceral afferents, sympathetic nerves and somatic sensory fibres enter the spinal cord?
Posterior rootlets
Why is pain from the heart of ten felt at higher dermatomes than the origin?
It depends where the visceral afferents enter the sympathetic chain
What causes referred pain?
Visceral afferents and afferent sensory fibres from the soma (somatosensory) enter the spinal crod at the same level
The body can mistake the pain, as originating from the somatic afferent nerve fibre location
In relation to the heart where is referred pain likely to come from?
Upper limbs, back, neck or jaw
What is myocardial infarction?
Irreversible death of the myocardial tissue due to necrosis caused by inadequate blood supply
The type of MI is related to what?
The affected surface of the heart
- Anterior
- Inferior
- Anterolateral
What are some common areas for occulusion in the coronary system?
- Left coronary artery
- Circumflex branch
- Anterior interventricular branch
- Right coronary artery
How is a coronary occulusion as a result of atherosclerosis treated?
A coronary artery bypass graft
Where can graft tissue be taken for a CABG?
- Radial artery
- Great saphenous vein
- Internal thoracic artery
The interventricular septum will normally receive blood from which two main arteries?
- Left anterior descending artery
- Posterior interventricular artery
What is the mediastinum?
The area housing the heart between the lungs
What is the superior “entrance” to the mediastinum called?
Thoracic inlet
In children, what is present in the anterior mediastinum?
Thymus gland
The plaxus of nerve on the oesophageal surface is called what?
Vagal plexus
What is present posterior to the oesophagus?
Thoracic aorta
Where is the thoracic duct located?
Between the oesophagus and azygous vein
The azygous vein has what role?
To drain blood from the intercostal spaces (posteriorly)
What are the branches at the arch of the aorta?
- Brachiocephalic trunk
- Left common carotid artery
- Left subclavian artery
How does blood supply to the intercostal spaces vary anteriorly versus posteriorly?
Anteriorly - Intercostal arteries from internal thoracic artery
Posteriorly - Intercostal arteries from thoracic aorta
Where does most lymph drain into the venous system?
The venous angle
Where the thoracic duct empties into the left subclavian vein
How is the thoracic duct more easily seen?
Reflecting the oesophagus
Where does the thoracic duct begin?
Cisterna chyli
(found in abdomen below the diaphragm)
Which branch of which nerve is given off at the level of the ligamentum arteriosum?
Recurrent larngeal branch of the vagus nerve
(will hook underneath ligamentum arteriosum)
The recurrent laryngeal nerve supplies what?
Voice box
Describe how the right recurrent largngeal nerve branches form the right vagus nerve
It branches more superior than the left and will hook under the right subclavian artery
What are the phrenic nerves formed from?
Spinal nerves C3, 4 and 5
The phrenic nerves will provide somatic motor innervation to the __________ and somatic sensory innervation to which other areas?
Diaphragm
Somatic sensory:
- Mediastinal parietal pleura
- Fibrous pericardium
- Diaphragmatic parietal pleura
- Diaphragmatic parietal peritoneum
Why does pain from the diaphragm get referred to the shoulders?
The supraclavicular nerves (C3,4) supply the dermatomes over the shoulders - thes eare sensory nerves
Both the supraclavicualr and phrenic nerves originate from the same spinal nerves so the brain attributes pain to the wrong area.
The vagus nerve supplies somatic sensory innervation to what?
- Palate
- Laryngopharynx
- Larynx
The vagus nerve supplies somatic motor innervation where?
- Pharynx
- Larynx
The vagus nerve supplies autonomic parasympathetic nerves to where?
Thoracic and abdominal organs
Recurrent largngeal nerves supply what?
Pharynx and larynx
After the recurrent laryngeal nerves have been given off which modalities remain in the vagus nerve?
Only parasympathetic fibres