Exam 2 Arrhythmias Flashcards
Which ventricle has a larger muscle mass and why?
Left ventricle
-has to squeeze blood out against higher pressure
What does the P wave represent?
Atrial depolarization
*not atrial contraction, immediately followed by it
What is the PR interval a measure of?
AV nodal conduction time
What drugs slow AV node conduction and can lengthen the PR interval?
Beta blockers
CCB (diltiazem, verapamil)
What does the QT interval represent?
Ventricular repolarization
What does the early part of the QRS wave represent?
Ventricular depolarization
What is an electrocardiogram?
Non-invasive representation of electrical activity of the heart
*12 lead often used
*3 lead good enough to diagnose arrythmias
How can we determine heart rate by looking at an ECG?
Multiple the number of R waves present by 10
(if 8 present, x10=80bpm)
What are the 4 questions to ask to determine if a rhythm is normal?
- Is there a P wave in front of every QRS complex?
- Is there a QRS complex after every P wave?
- Is the rhythm regular (interval between R waves all the same)?
- What is the heart rate (too slow/fast)?
What is QTc?
The corrected QT interval for heart rate
If the PR interval is longer than what it is too long?
0.2 seconds
(if P wave falls in one box and R wave is greater than a box away it is too long!)
What causes lengthening of the QRS interval?
Sodium blocking
Drugs that make what change to the ECG are the most concerning?
Lengthen the QT interval
AT what lengthening of the QT interval do we start to get concerned?
0.5 seconds or greater
(> or = 500 ms)
*increases Torsades de Pointes risk
When the QTc interval is > or = 500 ms, what does this increase the risk of?
Torsades de Pointes
What is a big risk with development of Torsades de Pointes?
Sudden cardiac death
What are the risk factors for developing Torsades de Pointes?
65 or older
Electrolyte imbalance (hypokalemia)
Heart failure
What are the 5 Supraventricular Arrhythmias?
(occur above the ventricles)
-Sinus Bradycardia
-Atrioventricular (AV) Block
-Sinus Tachycardia
-Atrial Fibrillation
-Supraventricular Tachycardia
What are the 3 Ventricular Arrhythmias?
-Premature Ventricular Complexes (PVCs)
-Ventricular Tachycardia
-Ventricular Fibrillation
What is considered “tachycardia”?
HR => 100
What is considered “bradycardia”?
HR => 60
What is sinus bradycardia?
HR < 60 BPM
Impulses originate in SA node
*Note: everything on ECG is normal, just too slow (Not enough R waves)
What is a common cause of sinus bradycardia?
Drug-induced
What is the mechanism behind sinus bradycardia?
Decreased automaticity of SA node
*depolarizes too slowly
What are some risk factors for sinus bradycardia?
MI or ischemia
Abnormal sympathetic or parasympathetic tone
Electrolyte abnormalities
What drugs can cause sinus bradycardia?
Digoxin
Beta blockers
CCBs (diltiazem, verapamil)
Amiodarone, Dronedarone
Ivabradine
*stop the drug unless patient needs it
*patients who need beta blockers may receive a pacemaker
What is idiopathic sinus bradycardia?
We do not know what is causing it
What are the symptoms of sinus bradycardia?
Hypotension (CO low)
Dizziness, Syncope (not enough brain perfusion)
When do we treat sinus bradycardia?
Only if symptomatic!
What is the treatment for sinus bradycardia?
Atropine 0.5-1mg IV, repeat every 5 min
Max dose: 3mg
If a patient with sinus bradycardia does not respond to atropine what do we do?
Start one of the following:
-Transcutaneous pacemaker (on skin)
-Dopamine 5-20 mcg/kg/mim
-Epinephrine 2-10 mcg/min or 0.1-0.5mcg/min
-Isoproterenol 20-60 mcg IV bolus then doses of 10-20 mcg or IV infusion of 1-20 mcg/min
*note: only start on one drug but can have on pacemaker and drug at same time
What are the adverse effects of atropine?
-Tachycardia
-Urinary retention
-Blurred vision
-Dry mouth
-Mydriasis (dilated pupils)
What patients experiencing sinus bradycardia require a different treatment regimen?
Heart Transplant patients
Spinal Cord Injury patients
**atropine will not work
What treatment should patients experiencing sinus bradycardia who have had a heart transplant or spinal cord injury receive?
Aminophylline 6 mg/kg IV over 20-30min
Theophylline
Heart Trans: 300 mg IV followed by po 5-10 mg/kg/day
Spinal CI: PO 5-10 mg/kg/day
What is the long-term treatment for sinus bradycardia?
Permanent pacemaker
OR
Theophylline po 5-10 mg/kg/day
What is the most common arrythmia?
Atrial Fibrillation
What is the mechanism of Afib?
Atria does not have enough time to fill with blood before constricting and passing into the ventricle
*Abnormal atrial/pulmonary vein automaticity
*Atrial reentry
What are the ECG features of Afib?
Activity: Chaotic, disorganized
HR: 120-180bpm
Rhythm: Irregularly Irregular
NO P WAVE (no atrial depolarization)
-ungulated (uneven) baseline
-interval between R waves are all different (irregularly irregular)
What feature of Afib causes the chaos seen on the ECG?
There is no single reentry circuit
-each reentry circuit tries to create a wave of depolarization and they interact with each other
-bombards the AV node with signals
What is Stage 1 Afib?
Presence of risk factors associated with Afib
(modifiable and nonmodifiable)
What is Stage 2 Afib?
Pre-Afib (not present yet)
-evidence of structural or electrical findings further predisposing the patient to afib
ex:
-atrial enlargement
-frequent atrial premature beats
-atrial flutter
What is Stage 3 Afib?
AFIB PRESENT
*Comes in 4 stages: A,B,C,D
What is Stage 3A Afib?
Paroxysmal Afib
-Intermittent
-Terminates within <= 7 days of onset
What is Stage 3B Afib?
Persistent Afib
-Continuous
-Sustains for > 7 days and requires intervention
What is Stage 3C Afib?
Long-Standing Persistent Afib
-Continuous for > 12 months in duration (year)
What is Stage 3D Afib?
Successful Afib Ablation
-No more Afib after percutaneous or surgical intervention to eliminate it
What is Stage 4 Afib?
Permanent Trial Fibrillation
-no further attempts at rhythm control made
-discontinue medications
*Left atrium can no longer contract blood into left ventricle, completely reliant on pressure changes
What are two causes of reversible Afib?
*Hyperthyroidism
Thoracic surgery
(CABG, Lung resection, Esophagectomy, Valve replacement surgery)
True or False: if a patient has Afib caused by hyperthyroidism and you manage the hyperthyroidism, the Afib is often also managed as well and does not require medication
True
What is a major reason why we need to treat Afib and why it is a concern?
Does not just cause symptoms, also causes morbidity and mortality!
**Undiagnosed Afib is a huge problem right now since it can present asymptomatically
What disease states associated with morbidity/mortality are more likely to occur with Afib?
Stroke/ Systemic Embolism (5x more)
Heart Failure (3x more)
Dementia (2x more)
Mortality (2x more)
What kind of strokes does Afib cause?
Large and devastating strokes
**the clots that are formed from Afib are big which makes the strokes more devastating
Where does a clot travel with Afib?
Forms in left atrium
Sucked into left ventricle even though the atria are nut pumping
Ends up in coronary artery
What are 3 lifestyle modifications that can be made to prevent Afib?
Weight loss (for patients with BMI > 27)
210 minutes vigorous exercise weekly
Smoking cessation
True or False: No amount of alcohol is safe with Afib
TRUE
-eliminate consumption
What are the goals of Afib therapy?
-Prevent stroke/ Systemic embolism
-Slow ventricular response (inhibit conduction of impulses to ventricle) (**ventricular rate control)
-Convert Afib to normal sinus rhythm
-Maintain sinus rhythm
What are the components of a CHADS-VASc Score?
Congestive heart failure
Hypertension
Age => 75 years
Diabetes
Stroke/ TIA
Vascular disease (MI, PAD, aortic plaque)
Age 65-74 years
Sex (female)
What components of the CHADS-VASc score are worth 2 points?
Age => 75 years
Stroke/ TIA history
Patients with what CHADS-VASc scores should receive anticoagulation?
Men: 1
Women: 2
*with afib
What is the preferred anticoagulation therapy for most patients with afib?
DOACs
*preferred over warfarin for most patients
In which patients with afib would warfarin anticoagulation be preferred over DOACs?
Mechanical heart valves
Afib associated with heart valve disease (moderate-to-severe mitral valve stenosis)
What is the typical INR target in patients?
2-3
What is the INR target in patients with a mechanical heart valve?
2.5-3.5
*slightly more aggressive
What is the INR target in patients with moderate-to-severe mitral valve stenosis?
2-3
*same as normal
In what patients with afib are Warfarin or Apixaban the preferred anticoagulation treatment options?
End-stage chronic kidney disease
Hemodialysis
What value indicates that a patient has end-stage chronic kidney disease?
CrCl < 15 mL/min
When should we measure INR of patients on anticoagulants?
During initiation: Weekly
After stable: Monthly
What is the antidote of Dabigatran?
Idarucizumab
What is the antidote of Rivaroxaban?
Andexanet alfa
What is the antidote of Apixaban?
Andexanet alfa
What is the antidote of Edoxaban?
Andexanet alfa
What drug (s) is Andexanet Alfa the antidote for?
Rivaroxaban, Apixaban, Edoxaban
What drug (s) is Idarucizumab the antidote for?
Dabigatran
What drugs can be used for ventricular rate control in patients with Afib?
Diltiazem (IV)
Verapamil (IV)
Beta Blockers
Digoxin
Amiodarone
What is the MOA of diltiazem, verapamil, and beta blockers regarding afib ventricular rate control?
Direct AV node inhibition
*reduces rapid heart rate but does not eliminate the Afib
What are the 3 beta blockers that can be used for rate control in Afib?
Esmolol
Propranolol
Metoprolol
What is the MOA of digoxin in rate control of Afib?
Vagal stimulation
Direct AV node inhibition
What is the MOA of Amiodarone in ventricular rate control of Afib?
Beta-blocker
Calcium channel blocker
What are some concerns regarding use of Amiodarone?
Many adverse effects
-Hypotension
Bradycardia
-Blue-grey skin
-Photosensitivity
-Corneal deposits
-Pulmonary fibrosis
-Hepatotoxicity
Hypothyroidism
-Hyperthyroidism
What are the 4 criteria for determining if a patient is hemodynamically unstable?
Systolic BP < 90
HR > 150 bpm
Loss of consciousness
Experiencing ischemic chest pain (possibly an MI)
If a patient with Afib is hemodynamically unstable what treatment should they receive?
Direct Current Cardioversion
(shock them)
If a patient with Afib is hemodynamically stable, and does not have decompensated HF what treatment should they receive?
Beta blocker, Diltiazem, or Verapamil IV
If the first line option for treatment of stable Afib without decompensated HF does not work (BB, Diltiazem, Verapamil), what are the other treatment options?
Digoxin
*if this also does not work, give Amiodarone
If a patient with Afib is hemodynamically stable, but has Decompensated HF, what treatment should they receive?
Amiodarone
**skip all other drugs (BB, Non-DHP CCB take too long to work)
What are the goals with Afib treatment?
HR <100-110 bpm
Asymptomatic
*increase medications until this occurs or shock
What medications should patients with HFrEF never receive?
Diltiazem + Verapamil
For patients with Afib and HFrEF, what medications should they receive for long-term ventricular rate control?
Beta Blockers (likely already on, make sure target dose achieved)
*If this does not reach goal, use Digoxin (combo)
For patients with Afib and HFpEF, what medications should they receive for long-tern ventricular rate control?
Beta blockers, Diltiazem, or Verapamil
*If this does not reach goal, use Digoxin
*note: Interaction with Dig and Verapamil, have to decrease Dig dose, better to switch to other option
What drug does Digoxin interact with that can affect Afib treatment?
Verapamil
*have to decrease the dose of Digoxin if using these concomitantly
*better to switch to BB or Diltiazem and avoid this
When is it safe to convert Afib patients to sinus rhythm?
If Afib present for <= 48 hours
If Afib has been present for > 48 hours (unsafe), and we want to convert the patient to sinus rhythm, what must be done?
Anticoagulate patient for 3 weeks
OR
Perform a Transesophageal Echocardiogram (TEE) to rule out a clot in the atrium
Why is it unsafe to convert an Afib patient to sinus rhythm if the Afib has been present > 48 hours?
Could dislodge a clot and cause a stroke
If a clot is found in an Afib patient’s atrium after performing a Transesophageal Echocardiogram (TEE), what should be done?
Do not convert to sinus rhythm
-Send patient home on anticoagulants and recheck TEE in 2 weeks
What treatments can be used to convert Afib patients to sinus rhythm?
DC cardioversion (elective or emergent)
Amiodarone
Ibutilide
Procainamide
Flecainide
Propafenone
Which two drugs are considered “Pill in the Pocket” drugs for converting Afib to sinus rhythm?
Flecainide
Propafenone
**paroxismal Afib patients will carry around a pill with them and if they feel symptoms they will take a single oral dose which will return them to sinus rhythm in a few hours
Which medication used to convert Afib patients tp sinus rhythm has a large risk of Torsades de Pointes?
Ibutilide
*po with lots of side effects
*Need to monitor QT interval
Why do we need to synchronize direct current cardioversion shocks?
So that they do not occur during a vulnerable period
-If the shock occurred on a T wave it could trigger ventricular fibrillation which is life threatening
In a patient with Afib who has normal LV function and is able to be converted to sinus rhythm, what treatment would we use?
IV Amiodarone or Ibutilide
first choice
(Amiodarone better, less Torsades de Pointes)
OR: Procainamide
**not first recommended, cannot start other two and switch, would have to use this from beginning
Can we initiate procainamide if patient has already received Amiodarone or Ibutilide?
NO
-increased risk of excessive QT prolongation and Torsades de Pointes
If a patient with Afib has HFrEF and is able to be converted to sinus rhythm, what treatment would you use?
IV Amiodarone
**only medication option, if it does not work we sedate and shock
**higher risk of Torsades de Pointes
In patients with Afib that occurs outside of the hospital and normal LV function, what treatment would we use?
“Pill-in-Pocket”
-Flecainide
-Propafenone
*single po dose
*DO NOT GIVE TO HF PATIENTS, WILL WORSEN
What two drugs used in Afib are associated with causing HFrEF exacerbations?
Flecainide
Propafenone
What drugs can be used to maintain sinus rhythm in Afib patients?
-Amiodarone
-Dofetilide
-Dronedarone
-Sotalol
-Propafenone
-Flecainide
When drugs are dosed for maintenance of sinus rhythm, how are they administered?
PO
What are the adverse effects of Amiodarone to be aware of?
Blue-grey skin discoloration
-Photosensitivity
-Pulmonary fibrosis
-Bradycardia
-Hypo/Hyperthyroidism
*skin discoloration is asymptomatic
*need to wear sunscreen
*pulmonary fibrosis is scar tissue in lungs
*may need pacemaker to stay on drug
*drug contains iodine which messes with thyroid
What is the scariest symptom of Amiodarone?
Pulmonary Fibrosis
(scar tissue in lungs)
What drugs interact with amiodarone?
Warfarin
Digoxin
Statins
What adjustment needs to be made if a patient is on warfarin and amiodarone at the same time?
Reduce warfarin dose by 1/3
What adjustments need to be made if a patient is on digoxin and amiodarone at the same time?
Reduce digoxin dose by 1/2
What is a concerning side effect of dofetilide?
Torsades de Pointes
What drug is contraindicated with dofetilide?
Verapamil
Why was dronedarone developed?
To be similar to amiodarone but with less side effects
**Important to note that this drug is less effective than amiodarone
What are important things to note about dronedarone side effects/ drug interactions?
*Does not contain iodine like amiodarone, will not affect thyroid
*Pulmonary fibrosis is rarer than with amiodarone
*Does not interact with warfarin
*Still interact with digoxin
What are the effects of sotalol?
Beta blocker but also has K channel blocking activity
How do we dose Dofetilide based on CrCl?
> 60: 500 mcg po BID
40-60: 250 mg po BID
20-39: 125 mg po BID
<20: Contraindicated
What does the QTc need to be at in order to initiate Dofetilide?
<= 440 ms
How do we initiate dofetilide in the hospital?
Initiate dosing based on CrCl
Adjust dose 2-3 hours after 1st dose (Check QTc interval)
If QTc increases <= 15%, continue current dose
If QTc interval increases > 15% or to > 500 ms, decrease dose by half!
If QTc is > 500 ms after second dose, discontinue
When dosing dofetilide, the QTc interval can increase by how much before we have to adjust the dose?
<= 15%
When dosing dofetilide, how much does the QTc interval have to increase before adjusting the dose?
> 15%
or
500 ms
*decrease dose by 1/2
When would we have to discontinue a dofetilide dose?
If QTc > 500 ms after 2nd dose check
What does the QTc have to be at before we can initiate Sotalol in the hospital?
<= 450 ms
How do we dose sotalol based on CrCl?
> 60: 80 mg BID
40-60: 80 mg once daily
<40: CONTRAINDICATED
How do we initiate sotalol in the hospital?
Only proceed it QTc <= 450ms
Dose based on CrCl
Check QTc interval 2-4 hours after dose
If QTc< 500ms after 3 days: discharge patient or increase dose to120 mg BID
If QTc>= 500: Discontinue
Which two drugs used for maintenance of sinus rhythm in Afib need to be started in the hospital?
Dofetilide
Sotalol
What monitoring needs to be done with Amiodarone?
TSH, Liver Function Test:
Init: 3-6 months
Follow-up: q 6 months
ECG: Annually
Chest X-ray: Upon symptoms of cough, dyspnea, or other lung symptoms
Corneal Microdeposits: If visual abnormalities occur
Dermatological: Physical exam annually
In a patient with Afib and normal LV function, and no prior MI or heart disease (HF), for maintenance of sinus rhythm what would be the recommended treatment?
Start one of these:
Dofetilide
Dronedarone
Flecainide
Propafenone
If it does not work (try multiple first-line first):
Amiodarone
Last Line:
Sotalol
In a patient with Afib with prior MI or heart disease (HFrEF), for maintenance of sinus rhythm what would be the recommended treatment?
MI:
Start Amiodarone or Dofetilide
Last line: Sotalol
HF:
USE ANYTHING EXCEPT DRONEDARONE
What drugs should patients with prior MI or Heart Disease/HFrEF never receive?
Flecainide
Propafenone
When can we use catheter ablation in Afib treatment?
-Improve symptoms in patients where antiarrhythmic drugs have been ineffective
-First line in: young patients with few comorbidities who have symptomatic paroxysmal Afib (intermittent)
What is catheter ablation?
Catheter inserted through vein into heart using fluoroscopy
-put into all 4 pulmonary veins
-delivers burn of energy and creates circular burn to electrically isolate and block faulty electrical impulses
*used for rhythm control
What are the characteristics of supraventricular tachycardia (SVT)?
Rhythm: regular
Narrow QRS complex
HR: Very fast, 110-250 bpm
Spontaneously initiates and terminates (paroxysms)
*All waves are present
What is paroxysmal SVT? (PSVT)
Subset of supraventricular tachycardia
-Intermittent episodes (paroxysms) of SVT
-Start suddenly and spontaneously, last mins to hours, terminate suddenly and spontaneously
What is the mechanism of Supraventricular Tachycardia (SVT)?
Reentry within:
AV node
-Accessory pathway
-Atria
-SA node
Has a single reentry circuit
**different than afib which has many
What side of the AV node do ablations occur on? (Slow or Fast)
Slow
-moves down AV node to depolarize ventricles, repolarizes atria
Who has a greater risk of developing Supraventricular Tachycardia?
-Women
-Age > 65 years
-Can occur with no underlying CVD
What is the defining symptom of Supraventricular Tachycardia?
Neck pounding
(force of blood going up coronary arteries)
True or False: SVT does not cause stroke
TRUE
Why do patients with SVT not need anticoagulation?
The atria are still contracting so blood is not able to pool and clot
What are the goals of therapy with SVT?
-Terminate SVT
-Restore sinus rhythm
-Prevent recurrences
What 4 drugs can be used to terminate SVT?
*Adenosine
Beta-Blockers
Diltiazem
Verapamil
By what mechanism do drugs that terminate SVT work?
Inhibit AV node conduction
How do we dose Adenosine in SVT?
6 mg IV bolus
no response in 1-2 mins:
12 mg IV bolus
*Can repeat 12 mg IV bolus once
**Remember: 6-12-12
*bolus done rapidly
What are the notable adverse effects of adenosine?
Chest Pain
Sinus Pauses (ECG flatline 2-3 secs)
What is the treatment options for termination hemodynamically stable SVT?
Vagal Maneuvers and/or IV Adenosine
if ineffective:
-IV Beta Blockers
-IV Diltiazem
-IV Verapamil
if ineffective or hemodynamically unstable:
-Shock (Synchronized DCC)
How can vagal maneuvers help with SVT?
-Stimulate vagus nerve to increase parasympathetic nervous system
-This causes HR to slow down and acetylcholine release
-Conduction to AV node inhibited
What is the treatment used to prevent recurrence of SVT?
No symptoms:
-follow-up, do not treat
Symptomatic:
Catheter ablation preferred
If no catheter ablation:
No HFrEF:
BB, Diltiazem, Verapamil
Then: Flecainide, Propafenone *not in CAD
HFrEF:
Digoxin
Amiodarone
Dofetilide
Sotalol
*at any point can opt into catheter ablation
What are the characteristics of Premature Ventricular Complexes (PVCs)?
Wide QRS complex
(all waves present though)
Occasional abnormal beats occurring randomly
What is Simple PVC?
Isolates single PVCs (irregular beats)
What are the frequent/repetitive forms of PVC?
Pairs of 2 beats: (Couplets)
Every 2nd Beat: (Bigeminy)
Every 3rd Beat: (Trigeminy)
Every 4th Beat: (Quadrigeminy)
Frequent: (At least 1 PVC on ECG, > 30 per hour)
What is considered Frequent PVC?
At least one PVC on 12-lead ECG
> 30 PVCs per hour
What is the mechanism of Premature Ventricular Complexes?
Increased automaticity of ventricular muscle cells/ Purkinje Fibers
*no reentry
What are the symptoms of PVC’s?
*Usually asymptomatic
Can have:
-palpitations, dizziness, lightheadedness
What risks are PVCs associated with?
Frequent PVCs:
-CVD
-Morbidity/Mortality
Very Frequent PVCs:
-Cardiomyopathy (can cause HF)
With CAD:
-Mortality
Survivors of MI:
Increased risk of sudden cardiac death (SCD)
How do we treat asymptomatic PVCs?
DO NOT TREAT
**know this
How do we treat symptomatic PVC in patients WHO DO NOT HAVE HF?
Beta Blockers
Diltiazem
Verapamil
If unresponsive:
Antiarrhythmic
If patient with PVC is unresponsive to BB, CCB, or Antiarrhythmic, what do we do?
Catheter ablation
**difficult for this arrythmia
How do we treat symptomatic PVC in patients with HF?
Beta Blocker
*only option
What are the characteristics of Ventricular Tachycardia?
Regular Rhythm
Wide QRS complex
*Series of consecutive PVCs, but all point upward
*Series of >=3 Ventricular Premature Depolarizations (VPD)
HR > 100 BPM
What is nonsustained ventricular tachycardia?
> = 3 consecutive Ventricular Premature Depolarizations (VPDs) that terminate spontaneously
What is sustained ventricular tachycardia?
VT lasting > 30 seconds
OR
Requires termination because of hemodynamic instability < 30 secs
What is Sustained Monomorphic Ventricular Tachycardia?
-Idiopathic VT (do not know cause)
-QRS complexes all the same
What are the 2 Types of Sustained Monomorphic Ventricular Tachycardia?
Verapamil Sensitive
Outflow Tract VT
(occurs in right or left ventricular outflow tract)
What are the mechanisms of Ventricular Tachycardia?
-Increased ventricular automaticity
-Reentry **Different from PVCs
What conditions can cause Ventricular Tachycardia?
-Coronary Artery Disease
-Myocardial Infarction
-HFrEF
-Electrolyte Abnormality
What drugs can cause Ventricular Tachycardia?
-Flecainide
-Propafenone
-Digoxin
If ventricular tachycardia is sustained, what may it progress to?
Ventricular Fibrillation
(bad, no pulse, no HR)
*risk for sudden cardiac death
What are the drugs used for termination of Ventricular Tachycardia?
Procainamide
Amiodarone
Sotalol
Verapamil
Beta Blockers
How do we terminate hemodynamically Stable VT in patients with Structural Heart Disease?
DCC (electric shock)
IV Procainamide
IV Amiodarone
IV Sotalol
If this does not work: DCC
How do we terminate hemodynamically Stable VT in patients who do not have structural heart disease?
Verapamil Sensitive: Verapamil
Outflow Tract: Beta Blocker
If this does not work: DCC
What treatments can be used to prevent recurrence of VT and Sudden Cardiac Death?
Implantable Cardioverter-Defibrillator (ICD)
Amiodarone
Sotalol
Catheter Ablation
Which treatment to prevent VT recurrence is best at mortality reduction?
ICD
How do ICDs work?
Detects VT or Vfib and delivers a shock
*does not prevent the episode but prevents patient from dying from it
**Can use drugs in combo with this if patient is receiving too many shocks
What VT patients are recommended to receive a catheter ablation?
Patients with prior MI and recurrent VT
-who present with VT and have failed or are intolerant to amiodarone or other antiarrhythmics
What does “fibrillation” mean?
Atria are quivering
What are the characteristics of Ventricular Fibrillation on an ECG?
Irregular, disorganized, chaotic electrical activity
**No recognizable QRS complexes or any waves at all
**No pulse, no BP, no CO, no blood pumped to body
What is asystole?
ECG flatline
What role does Vfib play in Myocardial Infarction?
Vfib is what these patients die of
What is a symptom of Vfib?
Sudden cardiac death
What is the only effective treatment for Vfib?
Defibrillation
*not the same as cardioversion
What is the difference between direct cardioversion and defibrillation?
Cardioversion is synchronized (avoids end of T wave)
Defibrillation is not synchronized (nothing to synchronize it to)
True or False: Drugs used alone will not terminate Vfib
TRUE
-only used to facilitate defibrillation
What are the 3 drugs we can give to facilitate defibrillation in Vfib?
Epinephrine
Amiodarone
Lidocaine
What is the algorithm for termination of Vfib?
CPR x 2min
Obtain IV/IO access
Defibrillate
CPR x 2 min
*Epinephrine 1 mg IV/IO
Defibrillate
CPR x 2 min
*Amiodarone 300 mg IV/IO OR Lidocaine 1-1.5 mg/kg IV/IO
**continue pattern, next dose of Amiodarone is 150 mg IV/IO or Lidocaine 0.5-0.75 mg/kg IV/IO
