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Basic Arrhythmias Seventh Edition Gail Walraven Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Appendix B Pathophysiology and Clinical Implications of Arrhythmias Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Cardiac Output • Total volume of blood pumped by heart in one minute Heart Rate x Stroke Volume = Cardiac Output Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ How Arrhythmias Impact Cardiac Output • Heart Rate: – Bradycardias – Tachycardias • Stroke Volume: – Ventricular rhythms Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Symptoms of Decreased Cardiac Output • • • • Anxiety Chest pain Shortness of breath Diaphoresis • • • • Hypotension Cool, clammy skin Cyanosis Decreased consciousness Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ General Treatment Principles Arrhythmias are treated when they cause (or are likely to cause) clinical symptoms. Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ General Treatment Principles All patients with arrhythmias (or the potential for them) should be monitored, receive oxygen, and have a keep-open IV as a precaution. Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Assess Perfusion • Assess perfusion parameters (BP, pulses, skin, etc.) to determine impact on cardiac output. Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Support Perfusion • In addition to treating the specific arrhythmia, you may need to provide ventilation, chest compression, and/or blood pressure support. Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Correct Underlying Conditions • Identify and correct hypoxia, acidosis, hypovolemia, etc. Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Matrix of Clinical Impact Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Treatment Concepts Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Normal Sinus Rhythm Significance • Normal cardiac pattern Clinical Picture • Does not produce symptoms Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Sinus Bradycardia • • • • Significance Can precede blocks or asystole Can precipitate escape rhythms or ventricular irritability Can be caused by AMI, vagal stimulation, increased intracranial pressure Can reflect normal, athletic heart Clinical Picture • Slow, regular pulse • Can cause signs/symptoms of decreased cardiac output Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Sinus Tachycardia Significance • Usually a compensatory response to fever, activity, pain, anxiety, hypovolemia, heart failure, etc. • Dangerous in AMI (can extend infarct) Clinical Picture • Rapid, regular pulse • Probably asymptomatic • Possibly palpitations, dyspnea Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Sinus Arrhythmia Significance • Common in children and young adults Clinical Picture • Irregular pulse • Rarely causes symptoms Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Premature Atrial Complexes • • • • Significance Clinical Picture Usually benign • Rarely causes Can be early sign of symptoms CHF Can lead to atrial tachyarrhythmias Causes include fatigue, hypoxia, dig-toxicity, caffeine, ischemia, CHF, alcohol Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Wandering Pacemaker Significance • Normal; often seen in very old or very young, or in athletes • Persistence of junctional rhythm can indicate heart disease Clinical Picture • Rarely causes symptoms Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Atrial Tachycardia Significance • Very dangerous in AMI or heart disease • Commonly caused by dig-toxicity Clinical Picture • Rapid, regular pulse • May show signs/symptoms of drop in cardiac output • Can cause pulmonary edema, CHF, shock Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Atrial Flutter • • • • Significance Rapid ventricular rate and loss of atrial kick can drop cardiac output Risk of pulmonary and cerebral emboli Can cause CHF or myocardial ischemia Seen in CAD, rheumatic heart disease Clinical Picture • Pulse can be regular or irregular, fast or slow • Rapid ventricular rate can cause signs/symptoms of low cardiac output Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Atrial Fibrillation Significance • Very rapid rate can lead to CHF or myocardial ischemia • Threat of pulmonary or cerebral emboli • Commonly caused by dig-toxicity Clinical Picture • Irregular pulse, can be fast or slow • Can have pulse deficit • Can cause signs/symptoms of low cardiac output Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Premature Junctional Complexes Significance • May precede AV block Clinical Picture • Rarely causes signs/symptoms Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Junctional Escape Rhythm Significance • Fail-safe mechanism • Can be normal, as with athletes Clinical Picture • Slow pulse • If rate is slow enough, can cause signs/symptoms of low cardiac output Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Accelerated Junctional Rhythm Significance • Indicates irritable junction overriding normal pacemaker • Often caused by AMI, open-heart surgery, myocarditis, digtoxicity Clinical Picture • Usually asymptomatic Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Junctional Tachycardia Significance • Indicates irritable junction overriding normal pacemaker • Often caused by AMI, open-heart surgery, myocarditis, digtoxicity Clinical Picture • Rapid, regular pulse • Can cause signs/symptoms of low cardiac output Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ First-Degree Heart Block Significance • Can be caused by anoxia, ischemia, AV node malfunction, edema following openheart surgery, digtoxicity • Can lead to more serious AV block Clinical Picture • Usually asymptomatic Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Second-Degree Heart Block, Type I (Wenckebach) Significance • Common following inferior MI • Can progress to more serious AV block Clinical Picture • Irregular pulse • Usually asymptomatic Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Second-Degree Heart Block, Type II Significance • Can be caused by anoxia, edema after open-heart surgery, dig-toxicity, hyperkalemia, anterior MI • This rhythm is dangerous because it can progress to further, more serious blocks Clinical Picture • Slow rate can cause signs/symptoms of low cardiac output Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Third-Degree Heart Block Significance • Can progress to ventricular standstill Clinical Picture • Very slow rate and abnormal pacemaker site severely impair cardiac output • Patients will frequently be unconscious from poor perfusion • Cardiac failure can follow quickly Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Premature Ventricular Complexes Significance Clinical Picture • Indicate ventricular irritability; increasing frequency indicates increasing irritability • Causes include ischemia/infarction, hypoxia, acidosis, hypovolemia, electrolyte imbalance, caffeine, smoking, alcohol • Patients can feel PVCs and be distressed by them • Pulse is irregular • Perfusion usually not impaired unless PVCs become frequent • Many factors can cause chronic PVCs in adults PVCs considered dangerous if: – Frequent or increasing frequency – patterns (bigeminy, trigeminy, etc.) – couplets – runs – R-on-T phenomenon – multifocal Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Ventricular Tachycardia Significance • Can quickly progress to ventricular fibrillation Clinical Picture • Patient will begin to lose consciousness as perfusion drops Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Ventricular Fibrillation Significance • Lethal arrhythmia • Indicative of extreme myocardial irritability Clinical Picture • Patient is clinically dead Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Idioventricular Rhythm Significance • Carries poor prognosis • Often associated with large MI and damage to large amount of ventricular muscle mass Clinical Picture • Patient is clinically dead Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ Asystole Significance • Carries very poor prognosis • Often seen after patient has been in arrest for some time Clinical Picture • Patient is clinically dead Gail Walraven, Basic Arrhythmias, Seventh Edition ©2011 by Pearson Education, Inc., Upper Saddle River, NJ