Anatomy
Name and describe the layers of the heart?
The endocardium is the innermost thin layer consisting of endothelium and connective tissue. This layer is continuous with the endothelium of the great vessels and provides a continuous closed system
The myocardium is a thick, muscular layer that includes all the atrial and ventricular muscle fibres necessary for contraction (myocardial contractility)
The epicardium is also known as the visceral pericardium, is tightly adhered to the heart and the base of the great vessels. Coronary arteries are situated on the top of the epicardium.
The pericardium is the outermost fibrous layer enclosing the heart and great vessels. It consists of two layers; parietal (outer) and visceral (inner) layer (also called the epicardium). It is a thick envelope that is tough, inelastic and provides a physical barrier to infection.
What is the intrinsic rate of the Sinoatrial (SA) node?
60-100BPM
Which coronary artery are most people dominant in?
RCA
What are the two types of action potentials with the heart?
What biomarker measures damage from trauma/ischemia or infarction?
Troponin - releases a protein biomarker
Which anatomnical structures represent the primary pumping chambers of the heart?
Ventricles
What is the intrinsic rate of the AV node?
40-60BPM
What is the intrinsic rate of the myocardial cells
20-35BPM
What happens at Phase 3 of the cardiac action potential?
Rapid repolarisation
What lead do you use to interpret an ECG rhythm strip?
lead 2
Which anatomical structures bring blood to the right and left atrium?
Pulmonary arteries
Name and describe the 4 cardiac muscle properties.
Automaticity: The ability of the cardiac myocytes to self-initiate an electrical impulse.
Excitability: Response to an electrical impulse
Contractility: Contractile response to an electrical impulse.
Conductivity: Transmission of an electrical impulse
What ECG leads are involved in an inferior infarction
II III AVF
What are the important ions for an efficient action potential?
On a 12 lead ECG, how many electrodes are needed?
10
What separates the left and right chambers of the heart?
atrial and ventricular septums
What is the intrinsic rate of the Bundle of His?
40-45BPM
What are the sub-branches that the Left main coronary artery subdivides into?
LAD and Circumflex
What represents atrial depolarization on a rhythm strip?
P wave
How many seconds is a big square with on a 12 lead ECG rhythm strip?
0.20 seconds
How many hearts does an earthworm have?
5
What is the beating sound from your heart sound like?
LUB DUB
What ECG leads are involved in a septal infarction
V1 V2
When does the refractory period of a cardiac cell begin?
Begins with the onset of phase 0 and ends just before the end of phase 3. On an ECG this extends from the beginning of the QRS complex to the end of the T wave. Refractory periods allow for complete emptying of the ventricles prior to the next contraction.
How many chambers in a cockroach heart
13