1 ECG Arrhythmias Flashcards
Ventricles are on the ____ of the heart.
Bottom
The atria empty into the corresponding______
Ventricles
The left ventricle provides for __________ circulation
Peripheral (body)
The right ventricle provides for _______ circulation
Pulmonary (lungs)
Describe the blood flow from Right atrium onward.
Right atrium> right ventricle> pulmonary artery> pulmonary circulation> left atrium> left ventricle> aorta> peripheral circulation> right atrium.
What is passive pumping?
The constant pressure of a distended arterial system wAnting to return to normal.
What is active pumping?
The actual pumping of the heart. Stroke volume, cardiac output
Cardiac Output=
Stroke volume x heart rate
A low stroke volume will lead to a _____ heart rate
Higher
What happens to the atria at late systole?
Atria are full, ventricles are empty
What happens during early diastole?
AV Valves open, blood goes to the ventricles
What happens during mid diastole?
The ventricles are full, atrial contraction forces the ventricles to distend, maximizing cardiac output.
A fast heart rate leads to ______ cardiac output, why?
Decreased The ventricles don’t have time to adequately fill or overfill to produce a decent contraction.
The AV Septum is a _______________ wall between the atria and the ventricles.
Non conductive
What is the function of the AV Septum in regard to electrical impulse?
Stops conduction before it reaches the ventricles.
What does the AV Node do?
It slows the atrial impulse down until the ventricles are ready to receive it, before opening and passing the impulse to stimulate the ventricles.
What is the slowing of the impulse at the AV Node called?
Physiologic blocking
How are the atrial myocytes innervated?
Direct cell to cell contact
Where is the Purkinje System located?
It encircles the ventricles and is the final component of the impulse system
Atrium are on the____ of the heart.
Top
What does the pacemaker of the heart do?
Determines the rate at which the heart will cycle through its pumping action. Creates an organized beating of all cardiac cells in a specialized sequence to produce effective pumping.
During excersize, the pace of the heart will____
Speed up
The main pacemaker of the heart is the_______ and is it located in the muscle of _______
SA Node. Located in the muscle of the right atrium.
What is the pacemaker of the heart controlled by?
Information from the nervous, circulatory and endocrine systems.
The main pacemaker of the heart paces at 60-100 BOM with an average of:
70 BPM
The fastest pacemaker of the heart is the:
SA node, then the AV node and so on
The fastest pacemaker sets the pace so all the slower ones can reset with each beat, what happens if the fastest pacer fails?
The next fastest will take over to try and return pacing to as normal as possible as quickly as possible.
What does SA node stand for?
Sinoatrial node
Where does the SA node get its blood supply in 59% of cases?
Right coronary artery
Where does the SA node get its blood supply in 38% of cases?
Left coronary artery
In the last 3% of cases where does the SA node get its blood supply?
Both coronary arteries.
Where exactly is the SA Node?
Muscle of the right atrium at its junction with the superior vena cava.
What are the three main internodal pathways?
Anterior, middle, posterior
What is the additional (fourth) internodal pathway?
Bachmans bundle which transmits impulses through the inter atrial septum
What is the function of the internodal pathways?
To transmit impulses through from SA to AV node.
Where are all of the internodal pathways found?
In the walls of the right atrium and inter atrial septum
Where is the AV node located?
Wall of R.A next to the opening of the coronary sinus, and septal leaflet of tricuspid valve.
Where does the Bundle of His start?
At the AV node
Where does the Bundle of His end?
The R and L bundle branches
The only route of communication between the atria and the ventricles is the_______.
Bundle of His
The left bundle branch starts at the bundle of His, and goes to the_______
Interventricular septum
The L.B.B is the first area to depolarize. True or false.
True
The R.B.B starts at the________ and ends at the ________.
Bundle of His Purkinje fibres
The left anterior fascicle travels through the R.V to the Purkinje fibres. True or false?
True
The left anterior fascicle is single stranded, true or false.
True
The left posterior fascicle is single stranded, true or false.
False, it’s fan shaped and harder to block because it is multi stranded.
What is the Purkinje system made of?
Cells beneath the endocardium
What are the 4 arrythmogenic zones?
1) SA node (sinus) 2) atrial 3) AV node (nodal) 4) ventricular
What are the rules for a wandering pacemaker?
Regularity: slightly irregular Rate: 60-100 P wave: morphology changes from one complex to the next PRI: less than .20 second QRS: less than .12 second
What are the rules for ectopic PAC’s?
Regularity: depends on the underlying rhythm; regularity will be interrupted by the PAC Rate: depends on underlying rhythm P wave: p wave of early beat differs from the sinus p waves; can be flattened or notched. May be lost in preceding t wave PRI: 0.12-0.20 seconds QRS: less than 0.12 second
What are the rules for atrial tachycardia?
Regularity: regular Rate: 150-250 bpm P wave: atrial p wave, can be lost in T wave PRI: 0.12-0.20 QRS: less than 0.12
What are the rules for atrial flutter?
Regularity: atrial rhythm is regular, ventricular rhythm is usually regular but can be irregular if there is a variable block Rate: atrial rate 250-350, ventricular varies P wave: sawtooth pattern PRI: Unable to determine QRS: less than 0.12 second
What are the rules for atrial fibrillation?
Regularity: grossly irregular Rate: atrial rate greater than 350, ventricular varies P wave: no discernible p waves; atrial activity is referred to as fibrillatory waves PRI: unable to measure QRS: less than 0.12 second
What do you do for stable vtach with a pulse (wide QRS)
Drug therapy, amiodarone or lidocaine
What do you do for unstable vtach with a pulse?
Synchronized cardiovert - 100 joules
What do you do for witnessed v-fib?
Chest compressions then defibrillate at 360 joules when ready
What do you do for unwitnessed vfib?
Chest compressions for 2 min before defibrillating
What do you do for stable sinus bradycardia?
Drug therapy - atropine 0.5 mg every 3-5 min
What do you do for unstable sinus bradycardia?
Pace on monitor at 70 bpm and increase milliamps until shows QRS, then check for pulse
What is a normal sinus rhythm with no pulse?
PEA
What do you do for stable SVT?
Attempt vagual maneuver (have patient blow on their thumb like they are trying to blow up a ballon) drug therapy = adenosine
What do you do for unstable SVT?
Cardiovert
What are the characteristics of SVT?
Over 160 bpm, tight QRS complex
What is the first drug you give for clinical death?
Epi 1:10,000 @ 1mg every 3-5 min
What are the rules for atrial tachycardia?
Regularity: regular Rate: 150-250 bpm P wave: atrial p wave, can be lost in T wave PRI: 0.12-0.20 QRS: less than 0.12
What are the rules for atrial flutter?
Regularity: atrial rhythm is regular, ventricular rhythm is usually regular but can be irregular if there is a variable block Rate: atrial rate 250-350, ventricular varies P wave: sawtooth pattern PRI: Unable to determine QRS: less than 0.12 second
What are the rules for atrial fibrillation?
Regularity: grossly irregular Rate: atrial rate greater than 350, ventricular varies P wave: no discernible p waves; atrial activity is referred to as fibrillatory waves PRI: unable to measure QRS: less than 0.12 second
What do you do for stable vtach with a pulse (wide QRS)
Drug therapy, amiodarone or lidocaine
What do you do for unstable vtach with a pulse?
Synchronized cardiovert - 100 joules
What do you do for witnessed v-fib?
Chest compressions then defibrillate at 360 joules when ready
What do you do for unwitnessed vfib?
Chest compressions for 2 min before defibrillating
What do you do for stable sinus bradycardia?
Drug therapy - atropine 0.5 mg every 3-5 min
What do you do for unstable sinus bradycardia?
Pace on monitor at 70 bpm and increase milliamps until shows QRS, then check for pulse
What is a normal sinus rhythm with no pulse?
PEA
What do you do for stable SVT?
Attempt vagual maneuver (have patient blow on their thumb like they are trying to blow up a ballon) drug therapy = adenosine
What do you do for unstable SVT?
Cardiovert
What are the characteristics of SVT?
Over 160 bpm, tight QRS complex
What is the first drug you give for clinical death?
Epi 1:10,000 @ 1mg every 3-5 min
What do leads 2,3, and AVF look at?
Left ventricle (inferior wall MI)
What do leads v-1 and v-2 look at?
Septum
What do leads v-3 and v-4 look at?
Anterior
What do leads v-5 and v-6 look at?
Lateral
What does ST elevation indicate?
Heart injury
What does ST depression indicate?
Heart ischemia
What is your treatment for a right sided MI?
Fluid
What is your treatment for a left sided MI?
Nitro
What does the right coronary artery feed?
SA node (60-100)
Why do heart blocks occur?
Result of conduction disturbances in the av node
What is a first degree heart block?
Not a true block, delay at the AV node but each impulse is eventually conducted through to the ventricles. Characterized by a PRI longer than .20 and constant. This will be the only abnormality in the arrhythmia.
What is a key feature of second degree heart blocks?
Not every P wave is followed by a QRS complex
What is the difference between wenckebach and type II second degree block?
The pattern in which the P waves are blocked, concentrate on the PR intervals
What rate is a type II second degree heart block usually?
Bradycardia
What is a key characteristic of type II second degree heart blocks?
Will always have more P waves than QRS complexes. It will be regular or irregular depending on the conduction ratio.
What is a key characteristic of wenckebach second degree heart block?
Increasing long PRI’s followed by a blocked p wave
Hypertension= what 3 possibilities?
Stroke, MI, Anuerism
What is the pathophysiology of hypertension?
Caused by increase in cardiac output, stroke volume, or both
What is the difference between primary hypertension and secondary hypertension?
Primary hypertension is usually treated early through medication and management and secondary hypertension usually develops secondary to another disease process. Secondary hypertension usually leads to hypertensive emergencies
What is the most common cause of secondary hypertension?
Renal disease
What is autonomic dysreflexia?
Person with neurogenic shock at t-6 loses sympathetic control distal to that. An unknown time period later they get a barrage of nerve stimulation usually in response to minor trauma or secondary insult
What causes the issue in a hypertensive crisis?
The speed of the increase of pressure
When there is an upside down or no p wave, what is the rhythm?
Junctional 1.) escape is 40-60 (unless QRS is too wide, then it is idioventricular) 2.) accelerated junctional is 60-100 3.) junctional tachycardia is above 100
When there is pressure on the heart that causes a change in rhythm, what does this cause?
Sinus arrhythmia (will be normal sinus rhythm except it is irregular)
If something is irregularly irregular, what are your options?
Afib, multi focal tachycardia
What classifies a first degree heart block?
PRI that is constant but prolonged, greater than 0.20
Fast, wide, regular?
Vtach
Fast, narrow, regular?
SVT
More P’s than QRS’s?
2nd or 3rd degree heart block
What are the rules for a normal sinus rhythm?
1.) regular 2.) 60-100 3.) uniform and upright p waves, one for every QRS 4.) PRI 0.12-0.20 and constant 5.) QRS less than 0.12
What are the rules for sinus bradycardia?
1.) Regular 2.) rate less than 60 3.) upright and constant p waves 4.) PRI 0.12-0.20 5.) QRS less than 0.12
What are the rules for sinus tachycardia?
1.) regular 2.) rate greater than 100 3.) uniform and constant p waves 4.) PRI 0.12-0.20 5.) QRS less than 0.12
What are the rules for sinus arrhythmia?
1.) irregular 2.) 60-100 rate 3.) uniform, constant, upright p waves 4.) PRI 0.12-0.20 5.) QRS less than 0.12
What is the key characteristic of wandering pacemaker?
Caused when pacemaker role switches from beat to beat between the SA node to the atria and back again
What will help you identify a wandering pacemaker?
The morphology of the p wave changes based upon the pacemaker site. There is a p wave for every QRS, but it may be more difficult to see depending upon the pacemaker site
What are the rules for PAC’s?
1.) regularity will be interrupted by PAC 2.) rate depends on underlying rhythm 3.) p wave of PVC WILL DIFFER from underlying p waves; may be flattened or notched 4.) PRI 0.12-0.20 5.) QRS less than 0.12
What are the rules for atrial tachycardia?
1.) regular 2.) 150-250 3.) will have atrial p waves, can be lost in T wave 4.) PRI 0.12-0.20 5.) QRS less than 0.12
What are the rules for Afib?
1.) grossly irregular 2.) atrial rate above 350, ventricular varies 3.) p waves are discernible/fibrillatory 4.) PRI is unable to measure 5.) QRS is less than 0.12
What are the rules for Aflutter?
1.) atrial rate is regular 2.) atrial rate 250-350 3.) p waves are sawtooth 4.) PRI is unable to determine 5.) QRS is less than 0.12
What is your treatment for Asystole?
BSI Check in 2 leads CPR O2 IV/Monitor 1 mg EPI every 3-5 Consider h’s & t’s
What is your treatment for PEA?
BSI CPR 02 IV/monitor 1 mg EPI every 3-5 Consider h’s & t’s
What is the MONA alogorhythm?
BSI ABC’s O2 IV/monitor/12 lead 325 mg aspirin 0.4 mg nitro 2-5 mg morphine
What is your treatment for polymorphic vtach with a pulse (torsades)
BSI ABC’s O2 IV/monitor/12 lead Mag sulfate 1-2 g over 5-60 min *if unstable treat as unstable vtach (chap present?)
What is your treatment for malignant PVC’s?
BSI ABC’s O2 IV/monitor/12 lead 1-1.5 mg/kg lidocaine 20-50 mg/min procainamide until QRS widens by 50% or 17 mg/kg is given or rhythm changes
What is your treatment for sinus bradycardia with a pulse or Brady 2nd degree heart block (wenckebach)?
BSI ABC’s O2 IV/monitor/12 lead 0.5 atropine IVP/ 3mg max TCP (not for 2nd degree block) Dopamine 2-10 mcg/kg/min EPI drip 2-10 mcg/min
What do you do for Brady 2nd degree heart block type II or 3rd degree heart block?
BSI ABC’s O2 IV/monitor/12 lead Consider 0.5 mg atropine IVP GO TO TCP
What do you do for narrow tachy with a pulse that’s stable?
BSI ABC’s O2 IV/monitor/12 lead/vagal 6 mg adenosine IVP 12 mg adenosine IVP
What do you do for narrow tachy with a pulse that’s unstable?
BSI ABC’s O2 IV/monitor/12 lead Sedation (midazolam 2-4 mg up to 10 mg) Synch cardioversion 100j Synch cardioversion 200j
What do you do for wide tachy with a pulse that’s stable?
BSI ABC’s O2 IV/monitor/12 lead Unknown origin? Consider 6 mg adenosine Lidocaine 0.5-0.75 mg/kg IVP or 150 mg amiodarone over 10 min
What do you do for wide tachy with a pulse that’s unstable?
BSI ABC’s O2 IV/monitor/12 lead Sedation (midazolam 2-4 mg up to 10 mg) Synch cardio 100j Synch cardio 200j
What is your treatment for pulse less vtach/vfib?
BSI CPR 02 IV/monitor Unwitnessed 2 min CPR/ witnessed 200j/360j Perform CPR as long as the patient is pulse less 1 mg EPI delivered every other cycle of CPR 200j/360j after 2 min CPR while in this rhythm 1.0-1.5 mg/kg lidocaine or 300 mg amiodarone IVP 2nd dose will be 0.5 mg/kg or 150 mg IVP *sequence is drug/shock/drug/shock
What is the equation for converting with lidocaine?
2g in 500 mL/ 4 mg/mL, 1-4 mg/min
What is the equation for an EPI drip?
2mg/500 mL
