Class 8 Flashcards
What are the two types of ventricular hyper trophy?
- Physiological ventricular hyper trophy
- Pathological ventricular hyper trophy
When do you see physiological ventricular hyper trophy?
And adapt and change to stress, to enhance pumping capacity of the heart
What are the two types of pathological ventricular hyper trophy?
- Afterload related
- Pre-load related
Afterload related ventricular hyper trophy is induced by what?
Increase in afterload, ventricle needs to generate a greater pressure chronically to reject blood
After load related ventricular hyper trophy can develop into watch?
Concentric hypertrophy
Concentric hypertrophy does what to pressure and compliance?
Generates a greater force and pressure but a decrease in compliance
Concentric paper trophy can lead to what happening to stroke volume and ESP? What does this result in?
Decreased SV, elevation of ESP, eventually diastolic disfunction and heart failure
Pre-load related ventricular hyper trophy does what to the heart?
Increase in ventricular heart stress, caused by volume overload
Volume overload in preload related hypertrophy causes what?
A dilated ventricle, inside radius of the ventricular chamber increases
A dilated ventricle generates what type of heart?
A hypertrophic heart, eccentric hyper trophy
Eccentric hyper trophy is often associated with what?
Systolic dysfunction, huge increase in LVESV & LVEDV
What are the two basic cardiac pacemaker’s?
- Sinoatrial node
- Atrioventricular
Which pacemaker is the native pacemaker?
SA node
Which pacemaker is the latent pacemaker?
AV node
Does membrane potential of the pacemaker cell remain constant at resting state after repolarization?
No
What is the term referring to the combination of both the automaticity and rhythmicity properties?
Autorhythmicity
What is referred to the ability of a cell to initiate its own pace making activity?
Automaticity
What is referred to the ability of a cell to maintain the regularity of peacemaking activity?
Rhythmicity
Autorhythmicity can be modulated by what?
- autonomic nervous system
- Hormonal system
Three variables that can influence cardiac rhythmicity 
- Rate of diastolic depolarization
- Maximum diastolic potential
- Threshold potential
What increases the rate of diastolic depolarization by increasing sodium and calcium influx?
Norepinephrine
Maximum diastolic potential induces hyper polarization by what?
By increasing potassium efflux 
Lowest conduction velocity ensures what?
Adequate ventricular filling
Highest conduction velocity ensures what?
Fast and coordinated ventricular contraction
What connects the SA node to the left atrium?
Bachmans bundle
What are the three internatal tracks?
Anterior, middle, and posterior
What are the three regions of the AV node?
- Atrionodal
- nodal
- nodal-his
What regions are the principal delay between atrial and ventricular contraction in the AV node?
Atrionodal and nodal
Why is there a delay between atrial and ventricular contraction?
To ensure adequate filling and limit frequency of impulses passing through AV node
What are the three main sections from AV node to ventricular contractile myocytes?
- Atrioventricular bundle/bundle of His
- Bundle branches
- Purkinje fibres
Where is the atrioventricle bundle?
Below AV node, passes through fibrous ring that separates atria and ventricles, reaches interventricular septum and forms two branches
Bundle branches are divided into right and left, what are they in?
Right bundle branch in right ventricle and left bundle branch in the left ventricle
Which bundle branch is considerably longer and thinner?
Right bundle branch
Inferior terminal branches of the bundle branches describe what?
Purkinje fibres
Purkinje fibres resemble what?
Cardiac myocytes
Intercollated discs that are well developed and contain numerous gap junctions can describe what?
Purkinje fibres
What has the fastest rate of conduction at any tissues within the heart?
Purkinje fibres
What are three possible accessory tracks that are not usually found in a normal individual?
- James fibres
- Mahaim fibres
- Bundle of Kent 
James fibres impulse bypasses AV node and can induce what?
Ventricular pre-excitation (Lang-Ganong-Levine Syndrome)
Fibres from atrial internodal tracks that pass around AV node and enter the interventricular septum describe what?
James fibres
James fibres bypass the AV delay and can result in the onset of what?
Supraventricular peroxisomal tachycardia
Any direct connections between AV node, bundle of His, or bundle branches into the interventricular septum describe what?
Mahaim fibres
Mahaim Fibres can give rise to what?
Ventricular pre-excitation
A muscular bundle for me a direct connection between atrial and ventricular myocardium describe what?
Bundle of Kent
Bundle of Kent is capable of doing what?
Giving rise to supra ventricular peroxisomal tachycardia‘s and atrial fibrillation
Bundle of Kent can give rise to the pre-excitation of the ventricle, a condition that is known as what?
Wolff-Parkinson-White Syndrome
