Module 2: Dysrthymias Flashcards

Question

First Degree AV Block

Answer 1

Associated with increasing age, disease states, and certain drugs  Usually not serious  Patients asymptomatic  No treatment  Monitor for changes in heart rhythm

Answer 2

May result from drugs or CAD  Typically associated with ischemia  Usually transient and well tolerated  Treat if symptomatic  Atropine  Pacemaker  If asymptomatic, observe closely

Answer 3

Associated with heart disease and drug toxicity  Often progressive and results in decreased CO  Treat with pacemaker  Treatment  Transcutaneous pacing or temporary pacemaker

Answer 4

Associated with severe heart disease, some systemic diseases, certain drugs  Usually results in decreased CO, ischemia, HF, and shock  Can lead to syncope  Treat with pacemaker  Drugs to increase heart rate if needed while awaiting pacing

Answer 5

Associated with stimulants, electrolyte imbalances, hypoxia, heart disease  Not harmful with normal heart but may reduce CO, lead to angina and HF in diseased heart  Assess hemodynamic status Treatment  Correct cause  β-blockers, lidocaine, or amiodarone

Answer 6

Develops when the intrinsic pacemaker rate (SA node or AV node) becomes less than that of ventricular ectopic pacemaker  Rate is between 40 and 100 beats/min  Atropine if patient symptomatic  Temporary pacing  Do not suppress rhythm

Answer 7

Ectopic foci take over as pacemaker -Normally, the heart's rhythm is controlled by the sinus node, located in the right atrium. In VT, ectopic foci (abnormal pacemaker sites within the ventricles) take over the role of the pacemaker. This results in rapid and often inefficient contractions of the ventricles. Types of VTach: Monomorphic VT: This is the most common type. "Monomorphic" means the heartbeats look similar to each other on an ECG. It occurs due to a single ectopic focus in the ventricles. Polymorphic VT: In this type, the ECG appearance of the heartbeats varies, indicating multiple ectopic foci within the ventricles. A subtype of this is Torsades de Pointes, which is often related to prolonged QT interval on ECG and can be very dangerous. Sustained VT: This refers to VT that lasts for more than 30 seconds. It is a medical emergency that requires immediate treatment, as it can lead to hemodynamic instability and progress to more serious conditions like ventricular fibrillation. Nonsustained VT: This form of VT lasts for less than 30 seconds and stops on its own. While it may not be immediately life-threatening, it often requires evaluation to assess the risk of more serious arrhythmias or underlying heart disease.  Considered life-threatening because of decreased CO and the possibility of development to ventricular fibrillation

Answer 8

Associated with heart disease, long QT syndrome, electrolyte imbalances, drug toxicity, CNS disorders  Can be stable (patient has a pulse) or unstable (pulseless)  Sustained VT causes severe decrease in CO  Hypotension, pulmonary edema, decreased cerebral blood flow, cardiopulmonary arrest Precipitating causes must be identified and treated (e.g., hypoxia)  VT with pulse (stable) treated with antidysrhythmics or cardioversion  Treatment for polymorphic VT with prolonged baseline QT interval includes IV magnesium, isoproterenol, phenytoin, or antitachycardia pacing  Pulseless VT treated with CPR and rapid defibrillation

Answer 9

Associated with acute MI, ischemia, chronic disease states, cardiac procedures  Unresponsive, pulseless, and apneic  If not treated rapidly, death will result  Treat with immediate CPR and ACLS  Rapid defibrillation  Drug therapy (epinephrine, amiodarone)

Answer 10

Total absence of ventricular electrical activity  No ventricular contraction  Patient unresponsive, pulseless, apneic  Must assess in more than one lead Usually result of advanced cardiac disease, severe conduction system problem, or end-stage HF  Treat with immediate CPR and ACLS measures  Epinephrine  Intubation  Poor prognosis

Answer 11

Electrical activity can be observed on the ECG, but no mechanical activity of the heart is evident, and the patient has no pulse  Prognosis is poor unless underlying cause quickly identified and treated H’s and T’s Mnemonic  Hypovolemia  Hypoxia  Hydrogen ion (acidosis)  Hyper-/hypokalemia  Hypoglycemia  Hypothermia  Toxins  Tamponade (cardiac)  Thrombosis (MI and pulmonary)  Tension pneumothorax  Trauma Treatment  CPR followed by intubation and IV epinephrine  Treatment is directed toward correction of the underlying cause

Answer 12

Death from a cardiac cause  Most SCDs result from ventricular dysrhythmias  Ventricular tachycardia  Ventricular fibrillation

Answer 13

 Life-threatening dysrhythmias caused by antidysrhythmia drugs  Severe LV dysfunction increases risk  Digoxin and class IA, IC, and III antidysrhythmic drugs  Most susceptible first few days of drug therapy

Answer 14

 Treatment of choice for VF and pulseless VT  Most effective when completed within 2 minutes of dysrhythmia onset  Passage of electrical shock through the heart to depolarize myocardial cells  Allows SA node to resume pacemaker role  Monophasic defibrillators deliver energy in one direction  Biphasic defibrillators deliver energy in two directions  Use lower energies  Fewer post shock ECG dysrhythmias  Output is measured in joules or watts per second  Recommended energy for initial shocks in defibrillation  Biphasic: 120 to 200 J  Monophasic: 360 J  Immediate CPR after first shock

Answer 15

 Therapy of choice for ventricular or supraventricular tachydysrhythmias (VT with a pulse)  Synchronized circuit delivers a shock on the R wave of the QRS complex of the ECG  Procedure similar to defibrillation except sync button turned ON  If patient stable, sedate prior  Initial energy lower  50 to 100 J (biphasic)  100 J (monophasic)  If patient becomes pulseless, turn sync button off and defibrillate

Answer 16

Appropriate for patients who  Have survived SCD  Have spontaneous sustained VT  Have syncope with inducible ventricular tachycardia/fibrillation during EPS  Are at high risk for future life-threatening dysrhythmias Decreases mortality

Answer 17

Consists of a lead system placed via subclavian vein to the endocardium  Battery-powered pulse generator is implanted subcutaneously  Sensing system monitors HR and rhythm— delivering 25 J or less to heart when detects lethal dysrhythmia  Includes antitachycardia and antibradycardia pacemakers  Overdrive pacing for tachycardias  Backup pacing for bradycardias  Pre-procedure and postprocedure care same as pacemaker  S-ICD

Answer 18

Used to pace the heart when the normal conduction pathway is damaged  Pacing circuit consists of  Power source *battery-powered pulse generator)  Programmable circuitry

Answer 19

Pace atrium and/or one or both of ventricles  Most pace on demand, firing only when HR drops below preset rate  Sensing device inhibits pacemaker when HR adequate  Pacing device triggers when no QRS complexes within set time frame Antitachycardia pacing: delivery of a stimulus to the ventricle to end tachydysrhythmias  Overdrive pacing: pacing the atrium at rates of 200 to 500 impulses/min to try to stop atrial tachycardias Cardiac resynchronization therapy (CRT)  Resynchronizes the heart cycle by pacing both ventricles * Biventricular pacing  Used to treat patients with heart failure  Can be combined with ICD for maximum therapy

Answer 20

For emergency pacing needs  Noninvasive  Bridge until transvenous pacer can be inserted  Use lowest current that will “capture”  Patient may need analgesia/sedation

Answer 21

Leads placed on epicardium during heart surgery  Passed through chest wall and attached to external power source  Leads placed prophylactically to treat dysrhythmias postoperatively

Answer 22

Electrode-tipped ablation catheter “burns” accessory pathways or ectopic sites in the atria, AV node, and ventricles  Nonpharmacologic treatment of choice for several atrial dysrhythmias  Postcare similar to cardiac catheterization

Answer 23

Brief lapse in consciousness accompanied by a loss in postural tone (fainting)  Noncardiovascular causes  Stress  Hypoglycemia  Dehydration  Stroke  Seizure Cardiovascular causes  Cardioneurogenic or “vasovagal” syncope * Carotid sinus sensitivity  Dysrhythmias (tachycardias, bradycardias)  Prosthetic valve malfunction  Pulmonary emboli  HF