Cardio Flashcards
What pathway does electrical activity travel in parts of the heart?
Endocardium to epicardium
What pathway does vascularization travel in parts of the heart?
Epicardium to endocardium
How does a pacemaker work?
Leads go in RV and left subclavian vein
At what HR do the ventricles receive no benefit?
> 140 bpm
What are the signs of an unstable pt?
Diaphoresis CP Hypotension AMS Pulmonary edema
What is considered hypotension?
SBP <90 mm Hg
What are drugs used to sedate a pt?
Etomidate
Propofol
What is the first step in treatment strategies?
Monitor IV Oxygen Crash cart Defibrillator Nurse/techs Prepare to run full resuscitation every time
What does a saw tooth pattern on EKG indicate?
Atrial flutter
What does a chaotic p wave pattern on EKG indicate?
A fib
What does variable p wave morphology on EKG indicate?
Multifocal atrial tachycardia
What are the narrow regular tachycardias?
SVT
Atrial flutter
Wolff-Parkinson-White
What is a common cause of SVT?
Illegal drugs
Revert procedure
For SVT
Put the head of the bed at a 45 degree angle
Tell the pt to blow the plunger out of a 10cc syringe as long and hard as they can
Once pt is fatigued, lay head of bed flat, raise legs 45 degrees
What are vagal maneuvers to perform for SVT?
Plunging face into basin of ice water
Carotid massage
Valsalva maneuver
These only work 17-20% of the time, whereas revert maneuver has a 40-60% efficacy
How should one treat SVT if vagal maneuvers don’t work
Adenosine -Ultra short AV blocker. Rapid administration. -Severe chest discomfort, asystole. -Unmask atrial flutter CCBs -Diltiazem/verapamil -Long-acting AV blockers -Slows A. flutter, does not convert
Tx for unstable SVT
Cardiovert at a rate of 25-75 J
Atrial flutter
Circular rhythm in the SA node, may eventually go to AV node
Atrial rate is 300, ventricular rate is 150
Tx for atrial flutter
BBs
CCBs
-Nondihydropyradines will slow atrial flutter but will not convert it, will slow ventricular response
Wolff-Parkinson-White
Circus movement arrhythmia that goes to the AV node but also goes to an ectopic node
- Orthodromic: clockwise direction- goes to AV node first
- Antidromic: counterclockwise direction- goes to ectopic node first
Tx for Wolff-Parkinson-White
AV nodal blocker
Cardizem
Metoprolol
What are the narrow and irregular tachycardias?
A fib
MAT- multiple atrial tachycardia
Atrial flutter with variable block
What are the atrial and ventricular rates for A fib?
Atrial: 600+
Ventricular: 170-180
Tx for A fib
Rate or rhythm control
-Rhythm: cardioversion/ drugs
-Rate control: Long-acting AV nodal blockers, CCBs, BBs (esmolol, metoprolol), digoxin
Cardioversion (200J) for unstable pts
Atrial flutter with variable block
Grouping of the saw tooth varies in terms of ratio
Treat with AV nodal blockers to control rate
Multifocal atrial tachycardia
Irregular but distinct P waves but different morphologies
Associated with COPD
Treat hypoxia
What are the tachycardias associated with a wide complex and regular rhythm?
V Tach
SVT with BBB
Antidromic Wolff-Parkinson-White
Tx of stable VTach
Amiodarone Procainamide Lidocaine Mg Adenosine
Tx of unstable VTach
Cardiovert (200J)
SVT with BBB
An atrial tachycardia with a BBB
May stop with adenosine
Antidromic Wolff-Parkinson-White tx
AV nodal blockers
What are the irregular wide tachycardias?
A fib with BBB
Torsades de Pointes
WPW + A fib
A fib with BBB
Most common cause of wide irregular rhythm
Treat with long-acting AV nodal blockers
Cardiovert if unstable
Torsades de Pointes tx
Mg
Cardioversion (200J)
WPW + A fib
Very rapid chaotic appearance rate may approach 300
Tx for WPW + A fib
CARDIOVERSION
AV blockers are dangerous
Procainamide only OK agent
HR general principles
The more abnl the heart rate, the more likely it is that it is responsible for the pt’s sx
The more extreme the heart rate, the more aggressive the tx will be
Whether the rate is very slow or very fast, tx decisions should be based on the appearance of the pt, not their actual hR
First step in bradycardia management
Monitor Airway equipment Defibrillator Pacemaker Crash cart
Ischemia as a cause of bradycardia
Think ACS
Electrolytes as a cause of bradycardia
Think potassium
Drug-induced causes of bradycardia
BBs
Others
Endocrine causes of bradycardia
Hypothyroid
General tx options for bradycardia
Cardioactive drugs
-Atropine 0.5 mg increments
-Epi 2-10 mcg increments
Pacing (transcutaneous/transvenous)
Bradycardia + CP/dyspnea
Ischemia may cause tachycardia or bradycardia
Large MI with CHF, PE, adrenergic tone
Bradycardia + acute coronary syndrome/MI
Bradycardia d/t ischemia of the conduction system or vagal response
Bradycardia with inferior MI usually narrow complex, transient, caused by vagal stimulation. Responds to atropine.
Bradycardia with anterior MI usually wide complex, caused by ischemia of the conduction system. Does not respond to atropine
Nitro may cause a reflex tachycardia (drop in preload/afterload). Contraindicated in severe bradycardia
Bradycardia + syncope
3rd degree AV block (Stokes-Adams attack)
Sick sinus syndromes
Bradycardia + overdose
Digoxin- ventricular arrhythmias
BBs- hypoglycemia
CCBs- hyperglycemia
Clonidine: Opioid like syndrome
Bradycardia + AMS
Consider overdose vs. increased ICP
Bradycardia + renal failure
Hyperkalemia
Bradycardia + myxedema
Tx is thyroid replacement
