Cardiac Conduction Autorhythmic cardiac muscle cells depolarize at

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Cardiac Conduction Autorhythmic: cardiac muscle cells depolarize at regular intervals p Cardiac Conduction system:

Cardiac Conduction Autorhythmic: cardiac muscle cells depolarize at regular intervals p Cardiac Conduction system: cardiac cells that are specialized to generate AP’s to control contractions of the heart p Pacemaker: the sinoatrial (SA) node, found in the R atrium starts HB and controls rate of contraction. AP’s from node travel down walls of atrium p

Cardiac Conduction Atrioventricular (AV) node: found by the AV valve, acts as a gateway

Cardiac Conduction Atrioventricular (AV) node: found by the AV valve, acts as a gateway carrying the AP’s from the SA node to the ventricles p AV bundle: a pathway for the AP’s from the AV node to travel through the septum as it splits into R and L branches toward apex of heart p Purkinje fibers: branches of the AV bundle that travel from the apex upward p

Cardiac Rhythm Sinus rhythm: normal heartbeat 7080/min p Nodal rhythm: caused by SA node

Cardiac Rhythm Sinus rhythm: normal heartbeat 7080/min p Nodal rhythm: caused by SA node damage 40 -50/min, AV node still working but ectopic focus working for SA node p If both SA and AV nodes are damaged then ectopic foci keep heart beating at 2040/min body lives but brain dies due to lack of oxygen p

Electrocardiogram (ECG or EKG): a visual record of the heart’s electrical activity p Systole:

Electrocardiogram (ECG or EKG): a visual record of the heart’s electrical activity p Systole: contraction of a heart chamber p Diastole: heart chamber relaxes and fills with blood p P wave: caused by the signal from the SA node as it spreads through the atria depolarizing the walls causing systole p

Electrocardiogram PQ segment: time it takes the signal to travel from the SA to

Electrocardiogram PQ segment: time it takes the signal to travel from the SA to AV node, p QRS complex: caused by the signal traveling through the two ventricles, p QRS interval: atria repolarization and diastole p ST segment: ventricular systole p T wave: the repolarization of the ventricles before diastole p

Cardiac Output (CO): CO= HR x SV normal CO =5250 ml/min so all blood

Cardiac Output (CO): CO= HR x SV normal CO =5250 ml/min so all blood in the body will pass through and return to the heart in about a min p Cardiac reserve: the difference of CO at rest and max CO p

Heart Rate Pulse: the heart rate measured at an artery p Tachycardia: persistent heart

Heart Rate Pulse: the heart rate measured at an artery p Tachycardia: persistent heart rate at rest above 100 bpm p Bradycardia: persistent heart rate at rest below 60 bpm p

Stroke Volume Preload: the stretch on the myocardium before systole p Contractility: how hard

Stroke Volume Preload: the stretch on the myocardium before systole p Contractility: how hard the myocardium can contract for a certain preload p Afterload: the blood pressure in the vessels that resists the blood flow out of heart p

The Cardiac Conduction System The Cardiac Conduction SystemThe Cardiac Conduction System The Cardiac Conduction System
Cardiac Conduction Physiology of Cardiac Conduction The excitatoryCardiac Conduction Physiology of Cardiac Conduction The excitatory
Cardiac Conduction Physiology of Cardiac Conduction The excitatoryCardiac Conduction Physiology of Cardiac Conduction The excitatory
Cardiovascular System Heart cardiac muscle physiology Cardiac conductionCardiovascular System Heart cardiac muscle physiology Cardiac conduction
Jeopardy Muscle characteristics Muscle Tissue Muscle anatomy MuscleJeopardy Muscle characteristics Muscle Tissue Muscle anatomy Muscle
Heart activity Modulation of autorhythmic cells Electrical activityHeart activity Modulation of autorhythmic cells Electrical activity
MUSCLE TISSUE 1 Skeletal muscle 2 Cardiac muscleMUSCLE TISSUE 1 Skeletal muscle 2 Cardiac muscle