The Heart Flashcards
Where is the heart located? In what orientation?
Mediastinum
Conical structure with an apex to the left of the midline and base on the posterior surface
2 primary layers of the pericardium
- Fibrous pericardium (strong layer of dense connective tissue)
- Serous pericardium (formed from 2 layers - parietal and visceral layer)
3 layers of the heart wall
Epicardium (visceral layer of the serous pericardium - outermost)
Mypcardium (consists of cardiac muscle arranged in circular and spiral patterns)
Endocardium (endothelium resting on a layer of connective tissue, lines the internal walls of the heart, simple squamous epithelium)
3 external markings of the heart
- Coronary sulcus (between the atria and the ventricles - has coronary arteries)
- Anterior interventricular sulcus (on the front)
- Posterior interventricular sulcus (on the back)
3 branches of the aorta
- Brachiocephalic trunk
- Left common carotid artery
- Left subclavian vein
3 vessels that empty into the RA
Superior vena cava
Inferior vena cava
Coronary sinus (vein of the heart)
Pectinate muscles
Ridges inside anterior of right atrium
Fossa ovalis
Depression in interatrial septum
Remnant of foramen ovale
3 things found on the internal walls of the right and left ventricles
Trabeculae carneae (cause elevations inside the heart) Papillary muscles (large and prominent trabeculae - can open the valve) Chordae tenineae
Which is the only bicuspid valve?
The mitral valve
From left atrium to left ventricle
Each valve is composed of
Endocardium with connective tissue core
Cardiac muscle cells
Short and branching
Have one or two nuclei
Not fused colonies
Join at intercalated discs
2 types of cell junctions at intercalated discs
Fasciae adherens (desmosome like) Gap junctions (holes connecting the cell - allow cells to contract together)
Parasympathetic fibers
Vagus nerve
Decrease heart rate
Sympathetic nerves
Cervical sympathetic chain
Increase heart rate and strength of contraction
The interventricular coronary arteries are also called…
The descending arteries
ex: left anterior descending artery
Angina pectoris
Chest pain
Myocardial infarction
Heart attack
Blocked coronary artery
Development of the heart (3 steps)
Heart folds into thorax by day 20-21
Heart starts pumping about day 22
Earliest chambers are unpaired
Most common congenital heart defect
Ventricular septal defect
2 basic categories of congenital heart defects
- Inadequately oxygenated blood reaches body tissues
2. Ventricles labor under increased workload
