KC Cardiac Flashcards
Define AMI
Acute myocardial infarction in the setting of an abonormal troponin (>99th percentile upper reference limit) PLUS one fo the following:
-symptoms of MI
-EKG abnormalities including ischemia or new q waves
-Imaging loss of myocardium or regional wall motion abnormality with ischemic cause
-angiography evidence of thrombus
List the classifications of angina
What is Prinzmetal angina? How do we manage it?
Coronary artery vasospasm at rest
Has minimal fixed coronary artery lesions
Often relieved with nitroglycerin
ECG may show STEMI pattern, should resolve with sympoms
Can treat with CCB, nitrates or a statin
Describe the 5 types of myocardial infarction
Type 5 also has new Q waves or LBBB, angio evidnce of new graft or native coronary occlusion, imaging loss fo myocardium
5 classic and 5 non classic risk factors for AMI
Classic - tobacco, HTN, DM, dyslipedemia, hsitory of AMI < 50 years
Non-classic - early menopause, cocaine, RA, HIV, SLE, antiphospholipid
What are complications of AMI?
Bradycardia - sinus, AV block (inferior)
Tachycardia - artial or venticular (anterior)
Cardiogenic shock - think big infarct, frail patient
Mechanical complications
LV rupture - first 24 hours to 5 days, sudden death
Septum or pap muscle rupture - 3-5 days, new systolic murmur and flash pulmonary edema
Stroke (LV anneursym, a fib that embolizes)
Besides ST elevation, describe ECG findings suggesting ischemia
Can be normal early
Hyperacute T waves
T wave inversions
STD
Q waves
STEMI equivelents: LBBB with scarbossa crtieria, DeWinter, Wellens, depression in V1, V2, elevation in aVR
What are the Smith-modified Sgarbossa criteria?
Concordant ST elevation >1mm in leads with a positive QRS
Concordant ST depression >1mm in V1-V3
Disconcordant ST elevations >5mm
- Revised criteria: significantly if ST elevation is >25% of the S wave
Patient is diagnosed with a STEMI and the cath lab is being prepared. What medications would you give?
ASA 162-325mg chewed
Plavix 600mg <75, 300mg >75 years
Heparin 60mg/kg bolus (up to 4000U)
What are the doses of plavix for:
1) PCI
2) Fibrinolysis
3) NSTEMI
What are 3 options for anti-platelet in ACS?
ASA 324mg chewable
Plavix either 300 or 600mg
Ticagrelor 180mg
What are two mechanisms of ASA? How well does it work with and without thrombolytics?
Irreversibly acetylates platelet cyclooxygenase (removes activity of platelet for 8-10 days)
Stop production of thromboxane A2 (encourages aggregation)
Without 23% reduction in mortality
With 42% reduction in mortality
What are mechanisms of Ticagrelor and Plavix? What is a difference
Both PSY12 inhibitors
Stop P2Y receptor from transforming into high affinity state - binds irreversibly for life of platelet
Plavix - Inhibits ADP platelet aggregator factor
Ticag: is reversible, does not need hepatic metabolism
Describe the antithrombins used in ACS and their indications
Unfractionated heparin: 60u/kg bolus (max 4000) used if going to PCI or kidney injury, reversible with protamine, risk of HITT
LMWH (Dalteparin, enoxaparin): 30mg IV bolus for dalteparin, enoxaparin 0.5mg/kg IV, use if delayed or no PCI, not great in in kidney injury, protamine partially effective
Fondaparinux: 2.5mg sub cut, use if delayed or no PCI. Factor 10a inhibitor, cannot give in kidney injury
Bivalirudin Direct thrombin inhibitor - used in STEMI is cant have UFH (allergy, HIT). No antidote very short half life
Describe the use of PCI vs. thrombolysis
Thrombolysis: presentation <3 hours, no PCI facility available, FMI to balloon time expected to be >120 mins (ex. Transfer), STEMI only
PCI: presentation >3 hours, contraindications for thrombolysis, cardiogenic shock, unsure of diagnosis
What are four options for thrombolysis and their doses?
tissue type plasma activator t-PA, 100mg total infusion over 90 minutes
Two recombinant t-PAs (TNK or retelplase), 30-50mg based on body weight
OG streptokinase (don’t use anymore)
Which thrombolytic do we give and why?
TNK
Longer half life so you can bolus it
14x more fibrin specific
80 times more resistant plasminogen activator
>4 hour presentation mortality benefit fewer non ICH bleeds
Describe the goal times for 1) FMC to ECG 2) FMC to balloon in a PCI centre 3) FMC to balloon in a non PCI centre 4) FMC to thrombolysis
1) <10 mins 2) <90 mins 3) <120 mins 4) <30 mins
Describe the ECG findings of a left main occlusion
Widespread horizontal ST depression, most prominent in leads I, II and V4-6
ST elevation in aVR ≥ 1mm
ST elevation in aVR ≥ V1
Differentiate between early and late post MI pericarditis? What are 2 drugs contraindicated in post MI percarditis?
Post MI - NSAIDs and steroids? CONFIRM THIS
What is the earliest finding of ischemia on ECG
Peaked T waves —> which will later progress into STE in typical STEMI
Outline the HEART score componets and scoring. What does it tell you?
HEART score predicts your short term risk of MACE defined as AMI, need for PCI or CABG, and death within 6 weeks of the ED visit.
Low – 1.7%, Moderate – 12-17%, High 50-65%
*What is the definition of STEMI (5 things)
New ST segment elevation in 2+ contiguous
leads >1mm in all leads other than V2-V3
For V2-V3:
≥2mm in Men >40years
≥2.5mm in Men <40 years
≥1.5mm in Women
*Ddx STE (6)
ST elevation mnemonic ELEVATIONS - electrolyte (hyper K, hypercalcemia), LBBB/paced, early repol, ventricular hypertrophy, Aneurysmal LV, thrombotic occlusion (MI), inflammation (pericarditis), Osborn (hypothermia), neurogenic, sudden death (Brugada)
plus three more P’s - Post cardioversion, PE, Prinzmental
*What are 6 causes of MI with normal coronaries?
Iatrogenic (aortic or coronary manipulation)
Trauma
Aortic dissection
Cocaine or other sympathomimetic abuse
Vasospasm
Sepsis
Tachydysrhythmia
Pregnancy
Thyrotoxicosis
Severe anemia
Hypoxia
Takotsubo
*What 3 treatments for ACS that have proven reduction in mortality? Please also list their mechanism of action.
ASA (antiplatelet)
Ticagrelor (antiplatelet)
reperfusion strategy such as PCI or fibrinolysis for STEMI (unless they were only referring to NSTEACS)
*What are 5 reasons to refer a patient to emergent PCI despite no STEMI?
1/ De winter
2/ AVR elevation with diffuse STD
3/ Wellens
4/ Posterior MI
5/ LBBB or paced meeting Sgarbossa criteria
6/ Post cardiac arrest
High risk NSTEMI
HD
Electrical instability - lethal arrythmia
Intractable ischemic pain
*What are the 3 acute mechanical complications of MI?
Papillary muscle rupture/regurgitation
Free wall rupture
Septal rupture
LV aneurysm
*The patient is found to have infarct pericarditis; what is the treatment?
Tylenol: IF remain symptomatic:
High dose ASA
*What are 5 risk factors for atypical MI presentation?
Female
Elderly
Non-white ethnicity
Diabetes
Dementia
No prior hx of MI
No FH of coronary disease
*Territory/artery involved in STEMI inferior leads
How can you tell which is which?
Inferior, RCA or LCx
*4 physiologic mechanisms why this patient would be hypotensive (inferior MI)?
- decreased RV contractility causing increasing right sided pressures, and decreased preload to right
- decreased preload to left
- RV dilation shifting septum decreases LV filling and therefore output
Brady from AV block
RV failure
Wall rupture
Septum rupture
Ischemic VSD
*2 reasons why – for patient going for PCI — ticagrelor better than Plavix? What are 2 reasons why you might not?
PLATO Trial
1. Improved vascular mortality (MI or CVA)
2. Reduction in all cause mortality
Higher rates of non-procedure related bleeding (Increase in ICH)
More recent data suggests no difference in MACE at 1 year
*3 risk factors for spontaneous coronary artery dissection (“SCAD”)?
*Where is the lesion: De-winter’s wave
LAD
*Where is the lesion: Bradycardia (rate 50) + TWI in aVL
RCA
*Where is the lesion: Infero-lat depression + AVR & V1 STE
Left main
*Where is the lesion: Anterior V1-V4 STE + inferior depression
Proximal LAD
*What 4 findings of BER on ECG? What is one example where you do want to be a little more wary?
- ST elevation –> Concave up
- Notching at the J point
- Symmetrically large T waves concordant
- Diffuse elevation
- No reciprocal changes
- Temporal stability (Constant) –> no dynamic changes
Exception is if only in limb leads - rare! Think about STEMI
*What are 2 findings for LV aneurysm on ECG.
- ST elevation, usually V1-V6, I, avL
- Q waves often “well formed” - indicate previous MI
- No reciprocal changes
- T:QRS amplitude > 0.36 - STEMI
*What are 4 clinical findings or findings on ancillary testing for takotsubo’s cardiomyopathy. What is 1 clinical item on history?
Tachycardia, hypotensive
STE
Trop elevation
Ballooning of the left ventricular apex is seen on ventriculography or echocardiography.
Clean cath
Recent intense emotional stress
*List three features on ECG that help to identify acute MI in a paced patient
Modified Sgarbossa
*5 causes of LBBB? What is Lenegere disease?
Also known as idiopathic fibrosis of the conducting system, or acquired complete heart block
Complete and permanent atrioventricular block is often the consequence of lesions involving both bundle branches, and not of a lesion in the common bundle
*Recognize Wellens type A and B - how to manage? (3) Where is the lesion? What are your options for management?
STEMI equivalent
Type B - deep symmetrical T wave inversion (75%)
Type A - biphasic T wave changes in the anterior precordial leads (25%)
Other features <1mm STE and no precordial q waves
Proximal LAD lesion that can preceed STEMI
Stable and no CP - DAPT, fonda and cardio (cath wont take but let them know
Unstable, onging pain, on nitro infusion - DAPT + heparin +cath
*What are 5 absolute contraindications for thrombolysis in STEMI? 5 relative?
Absolute is 1-2-3, One head bleed ever, spine surgery 2 months, head trauma 3 months, ischemic stroke 3 months and aortic dissection
What are EKG criteria for successful fibrinolysis?
Reduction > 50% of STE within 1 hour
Significant relief of pain
*5 causes or precipitants of afib
Hypertensive heart disease
Cardiomyopathy
Ischemic heart disease
Valvular disease (especially mitral)
Congestive heart failure
Pericarditis
Hyperthyroidism
Sick sinus syndrome
Myocardial contusion
Acute ethanol intoxication (holiday heart syndrome)
Idiopathic
Cardiac surgery
Catecholamine excess
Pulmonary embolism
Accessory pathway (Wolff-Parkinson-White) syndrome
*Best choice for medical cardioversion
Procainamide - 1A
It slows down conduction in everything except for the SA node, including accessory pathways
Use it WPW
Flecanide (supported UTD), propafenone
1C - Flecainide can be used for some SVT and VT
Requires a lot of caution, variable half life, narrow therapeutic index – why it isn’t first line and first dose needs to be observed
Also be careful if someone has structural or ischemic heart disease (why young people get pill in pocket)
Profoundly slow depolarization to the point they can make new arrythmias way worse then 1A
*4 reasons not to cardiovert due to increased risk of stroke
- Valvular AF (any duration), or
- NVAF Duration <12 hours and recent stroke/TIA, or
- NVAF Duration 12-48 hours and CHADS2
≥2, or - NVAF Duration >48 hours
*According to 2016 CCS guidelines: 5 reasons to start someone on oral anticoagulation (answer now with 2018)
2018 indications afib plus:
1. Any CHADS2 RF needs OAC
2. Valvular AF
3. Cardioversion plus (OAC 4 weeks)
i. Hemodynamically unstable acute AF, or
ii. NVAF Duration <12 hours and no recent stroke/TIA, or
iii. NVAF Duration 12-48 hours and CHADS2<2
*List 5 completely irregular/chaotic heart rhythms
- Atrial fibrillation
- Atrial tachycardia or flutter with varying conduction
- Multifocal atrial tachycardia
- Multiple extrasystoles
- Wandering pacemaker (usually atrial)
- Parasystole
*List 4 clinical findings that hint at cardiac instability from arrhythmia
- HD unstable
- Chest pain
- Dyspnea
- aLOC
*List 6 patient related factors to take into account when deciding to rate or rhythm control a patient
- Stable or unstable
- Onset of symptoms (new-onset or newly recurrent, with duration < 48 h)
- Anti-coagulation status
- Valvular disease
- Hypokalemia (increases risk of ventricular fibrillation)
- Digitalis toxicity (increases risk of ventricular fibrillation)
*List 4 medications that can be used for rhythm control
- Procainamide
- Amiodarone
- Ibutilide
- Propafenone
- Flecainide
*List the 7 components of the CHADS2-VASc score
- Congestive heart failure
- Hypertension
- Age >= 75 years
- Diabetes mellitus
- Any previous stroke, transient ischemic attack, embolism
- Gender–female
- Age, 65-74
- Vascular disease (history of MI, PAD, or aortic atherosclerosis)
*What score is “moderate risk” and requires anticoagulation?
Scores of 2 or higher, anticoagulation is recommended
*Explain pre-excitation in terms of cardiac conduction?
Accessory pathway offers an alternate route for the atrial impulses, so they can bypass the AV node, flow through the fast accessory pathway, causing early excitation of the ventricles which shows up as a slightly wider, slightly early QRS complex (for instance, the delta wave in WPW)
*3 ECG findings of WPW
- Short PR
- Delta wave
- Wider QRS
*Recognize Brugada type I and II
EKG
Remember Brugada sign is type 1 only that is potentially diagnostic
1 - Coved ST segment elevation >2mm in >1 of V1-V3 followed by a negative T wave.
2 - Brugada Type 2 has >2mm of saddleback shaped ST elevation.
3 - Either but with less than 2mm of elevation
*2 most common dysrhythmias in people with WPW?
Orthodromic AV reentrant tachycardia
Afib
*AFib with wide complex given – what’s the most acceptable medication to use?
Procainamide (or cardioversion)
*Which two medications are contraindicated in WPW with afib?
ABCD
1. Adenosine
2. Beta blockers
3. CCB
4. Dig
*Explain why above medications are dangerous in this case.
Treatment with AV nodal blocking drugs e.g. adenosine, calcium-channel blockers, beta-blockers may increase conduction via the accessory pathway with a resultant increase in ventricular rate and possible degeneration into VT or VF
*3 reasons to use warfarin over NOAC for a fib
- Valvular AF (includes mechanical mitral valve and mitral stenosis)
- Cost
- Patient preference
- Renal insufficiency? Low body weight?
*What are 7 classes of causes (besides metabolic) that would cause this rhythm disturbance (complete heart block)?
- Increased vagal tone
- Progressive cardiac conduction system disease (i.e. fibrosis, sclerosis, calcification)
- Ischemic heart disease/myocardial infarction
- Infiltrative cardiomyopathy (e.g. secondary to sarcoidosis, amyloidosis, malignancy)
- Non-ischemic cardiomyopathy (e.g. post-infectious, such as Chagas disease)
- Drugs (e.g. beta-blockers, calcium channel blockers, digoxin, anti- arrhythmic)
- Cardiac surgery (e.g. post valvular surgery)
- Transcatheter aortic valve implantation
- Catheter ablation of arrhythmias
*List 4 etiologies of torsades
Non-Drugs:
- Congenital long QT and other congenital syndromes
- Electrolyte abnormalities: hypokalemia, hypomagnesemia, hypocalcemia
- Diet-related: starvation, low protein
- Severe bradycardia or AV block
- Hypothyroidism
- Contrast injection
- Cerebrovascular accident
- Myocardial ischemia
Drugs:
- Class IA anti-dysrhythmic (e.g. procainamide)
- Class IC anti-dysrhythmic (e.g. propafenone)
- Butyophenones (e.g. haloperidol)
- TCA
- Antibiotic (e.g. macrolides)
- Organophosphates
- Anti-histamine
- Anti fungal
*3 Treatment for torsades
Pulseless: Defibrillation Unstable: Cardioversion Stable:
- Cease QT prolonging medications
- Empirical IV magnesium sulfate (2 g over 10-20 minutes and then infusion at 1-4 g/hr)
- Correct underlying metabolic disturbances (i.e. hypokalemia, hypocalcemia)
- Overdrive pacing (ie chemical or medical with isoproterenol) target rate of 90 100 beats/min higher occasionally
*Treatment for VT
Stable: Amiodarone or procainamide
Unstable: Cardioversion at 100J
**Remember, if unsure if SVT with aberrancy vs VT, treat as VT.
*What are the components of the CHADS-Vasc score?
CHADS2:
CHF
HTN
Age >75
Diabetes
Stroke or TIA previously (2)
CHA2DS2VASC:
CHF
HTN
Age >65,>75 (2)
Diabetes
Stroke or TIA, previously (2)
Vasc HX (MI, PAD)
Sex (F = 1)
*How to estimate stroke risk in 1 year with CHADS scores?
Rule of thumb is to double whatever the score is.
*List 3 electrolyte disturbances that cause long QT.
- Hypomagnesemia
- Hypokalemia
- Hypocalcemia
*Name 2 congenital causes of torsades
Jervell and Lange-Nielsen syndrome (deafness, autosomal recessive)
Romano-Ward syndrome (normal hearing, autosomal dominant)
Sporadic (normal hearing, no familial tendency)
Mitral valve prolapse
Describe the phases of an action potential
Depolarization via Na influx
Plateau phase with stabilization of calcium
Repolarization with K efflux
Refractory period and restoration of ion balance by Na/K ATP pumps
List 4 classes of cardiovascular drugs, list examples of each and briefly describe their mechanism of action
Some Block Potassium Channels
Class I: sodium channel blockers ex. Procainamide, lidocaine. Block sodium channels effectively increasing refractoriness
Class 2: beta blockers ex. Metoprolol. Depresses the SA node, slows AV node conduction
Class 3: potassium channel blockers ex. amiodarone, sotalol. Prolongs actions potential and refractory periods (prolongs Qtc)
Class 4: calcium channel blockers ex. verapamil. Slows conduction in the AV node
Describe the subtypes of Class I sodium channel blockers
“Quarter pounder, lettuce pickles, fries please”
1A: quinidine, procainamide
1B: lidocaine, phenytoin
1C: flecainide, propafenone
Which sodium channel blockers are generally used for supraventricular vs. ventricular tachycardias
Class IA and 1C and generally better for supraventricular tachycardias as they prolong repolarization, and 1B for ventricular tachycardias as it shortens repolarization
Which sodium channel blockers also block potassium channels
Class 1A and 1C
List 2 side effects of procainamide
Qt prolongation, hypotension
List 10 sodium channel blockers
Quinidine, procainamide, lidocaine, phenytoin, flecainide, propafenone
antimalarials (chloroquine), local anesthetics, diphenhydramine, cocaine, propranolol, carbamazepine
Describe the difference between beta 1 and beta 2 receptors
B1: mainly myocardium, increases inotropy + chronotropy, activates cAMP
B2: bronchial and visceral smooth muscle, increases bronchodilation and vasodilation
Which beta blockers are cardio selective? Why is this important?
A-M cardio selective block B1 ex. Atenolol, metoprolol
N-Z nonspecific B1 and B2 (can cause bronchospasm in asthmatics) ex. Nadolol
Which beta blockers have mixed alpha and beta activity
Olol - pure beta blocker
Vowel -lol alpha and beta blocker ex. labetalol
What is a first degree heart block
PR interval >200ms, no treatment necessary
What is a second degree heart block Type 1
Type 1 (Wenckebach): progressive prolongation of the PR intervention while the P-P interval remains constant. Ends in a non conducted p wave. Due to a conduction block at the AV node. No treat if asymptomatic
What is a second degree heart block Type 2
Type 2 (Mobitz): intermittent non conducted P waves without progressive prolongation of the PR interval. Due to a conduction block below the AV node. More likely to be associated with hemodynamic instability; may need pacing
What is a third degree heart block
None of the P waves are conducted to the ventricles. May be an junctional or escape ventricular rhythm.
How is afib diagnosed on ECG
absence of discernible P waves and an irregular rhythm
List 5 causes for afib
HTN, CAD, cardiomyopathy, valvular heart disease, hyperthyroidism, cardiac contusion, CHF, pericarditis, PE
List indications for cardioversion of AF
Hemodynamically unstable acute AF
NVAF duration <12 hours and no recent stroke/TIA
NVAF 12-48 hours and CHADS2 <2
What is the definition of valvular AF
mechanical valve, rheumatic mitral stenosis, or more than moderate mitral stenosis
List 3 drugs that can be used for rate control in AF
Metoprolol
Diltiazem
Digoxin
List 3 drugs that can be used in rhythm control in AF
Amiodarone
Procainamide
Flecainide
Briefly describe the landmark studies in rate vs. rhythm control for chronic management of AF
AFFIRM and RACE show that embolic events occur with equal frequency
AFFIRM: Trend towards decrease mortality with rate control, but no difference in terms of death or rate of stoke
RACE: Similar findings to AFFIRM; trend towards lower mortality with rate control but no divergence in cardiovascular mortality. Trend towards non fatal endpoints in rhythm control (ex. heart failure VTE) thought to be S/E of the anti arrhythmia drugs
As per the CCS, which patients with AF should receive OAC
- Age >65
- Any CHADS - CHF, HTN, diabetes, prior stroke or TIA
CAD or PAD should get antiplatelet therapy ex. ASA
What is the risk of cardioversion in a patient with AF
No anticoagulation - 30 day incidence of 2.39%, with a background rate of 0.5% if no cardioversion is performed
Anticoagulation - 0.27%