6/12/2014 Cardiovascular Boot Camp Basic Cardiac ArrhyTtrhaminiains:g P Dhyasyi o2lo: g ic Links to ReCcaorgdniiatico nA arrnhdy Mthamnaiagse manendt Emergency Trea tment Overview NTI 2014 Denver Karen Marzlin DNP, RN, CCNS, CCRN-CMC, CHFN Contact Information: [email protected] 2014 1 Knowing is not enough; we must apply. Willing is not enough; we must do . Johann Wolfgang von Goethe 2 1 6/12/2014 Electrical Conduction Pathway • SA Node • Interatrial pathways • AV Node • Bundle of His • AV Junction • Right and Left Bundle Branches • Anterior and Posterior Fascicles • Purkinge Fibers 3 • P wave: atrial depolarization WAVES and • QRS: ventricular depolarization • T wave: ventricular repolarization COMPLEXES • PR interval: AV conduction time • QRS width: intraventricular conduction time QRS • ST Segment: sustained ventricular depolarization • QT interval: used to reflect ventricular repolarization time T P QT Interval PR Interval ST Segment QRS 4 2 6/12/2014 Overview of Bradyarrhythmias • Sinus bradycardia • Second Degree Type I • Sinus exist block • Second Degree Type II • Sinus Pause or Arrest • High Grade AV Block • Junctional Rhythm / • Complete Heart Block Escape • Idioventricular Rhythm / Ventricular Escape 5 SA Block or SA Exit Block 6 3 6/12/2014 SA Block or SA Exit Block 7 Sinus Arrest or Sinus Pause 8 4 6/12/2014 Junctional Escape and Rhythm 9 Wenckebach (2nd Degree Type I) Note: Progressive lengthening of the PR interval (problem in the AV node) Normal QRS width (no problem in the His Perkinge System) 10 5 6/12/2014 2nd Degree Type II Both of these examples: 1. One P wave at a time fails to conduct 2. There is a fixed PR interval 3. There is a wider than normal QRS 11 Heart Blocks - High Grade AV Block • Two or more consecutive atrial impulses are blocked. • This is not 2nd degree heart block by definition because more than one P wave in a row fails to conduct. • However, this is not complete heart block because there is not complete AV dissociation. 12 6 6/12/2014 Third Degree AV Block – Complete • No atrial impulses are conducted to the ventricles • One form of AV dissociation • Ventricular Rate: Maintained by ventricular escape (wide QRS) or by pacemaker coming from His bundle (narrow QRS – less common) 13 Ventricular Escape Beats II V 1 1144 7 6/12/2014 Idioventricular Ventricular Rhythm II 1155 Classification of SVT • Sinus Tachycardia – Physiological • AV Nodal Reentrant Tachycardia – Inappropriate – SANRT • AV Reentrant Tachycardia • Atrial Tachycardia – Orthodromic – Focal – Antidromic – Intra-atrial reentrant – Multi-focal • Atrial Flutter • Atrial Fibrillation • Junctional Tachycardia – Nonparoxysmal JT – Junctional ectopic tachycardia 16 8 6/12/2014 Two Reasons Why a Patient Develops a Tachyarrhythmia Ectopic Foci Conduction Disturbance • Focus other than sinus node • An impulse does not travel takes over as pacemaker of normally down the heart. conducting pathways but • Enhanced or abnormal rather finds a way to re- automaticity. enter the conducting pathways • Tachycardias with this etiology are called re- entrant tachycardias 17 Understanding the Origin of Arrhythmias • Disorder of impulse initiation • Abnormal automaticity – Enhanced – Abnormal • Triggered mechanism: disturbance in recovery or repolarization (less common) –Early or delayed after depolarizations • Disorder of impulse conduction • Reentrant Circuit (Most common) 18 9 6/12/2014 Atrial Arrhythmias Organized Disorganized • Atrial tachycardia • Atrial fibrillation • Atrial Flutter 19 Paroxysmal Atrial Tachycardia (PAT) with Block 20 10
Description: