Cardiac Arrhythmias Name That Rhythm Kathaleen Johnson DNP, CRNP, CCRN

Objectives Identify common arrhythmias that cause dyspnea List diagnostic tests used to determine the cause of these arrhythmias Describe treatment options for these arrhythmias

Common Arrhythmias that Cause Dyspnea PSVT (paroxysmal superventricular tachycardia) Atrial fibrillation Atrial flutter Heart blocks Ventricular arrhythmias

Let’s start with a normal rhythm

Basics on Where to Start with Interpreting ECG’s Rate Rhythm Intervals Axis Hypertrophy Ischemia or infarct

Normal Sinus Rhythm Implies normal sequence of conduction, originating in the sinus node and proceeding to the ventricles via the AV node and His-Purkinje system. EKG Characteristics: Regular narrow-complex rhythm Rate bpm Each QRS complex is proceeded by a P wave P wave is upright in lead II & downgoing in lead aVR

Atrial Fibrillation Irregular rhythm Absence of definite p waves Narrow QRS Can be accompanied by rapid ventricular response

Atrial Fibrillation—causes and associations Hypertension Hyperthyroidism and subclinical hyperthyroidism CHF (10-30%), CAD Uncommon presentation of ACS Mitral and tricuspid valve disease Hypertrophic cardiomyopathy COPD OSA ETOH Caffeine Digitalis Familial Congenital (ASD)

Demographics Common; 2.2 million people in the U.S. Male>Female Prevalence increases with age Leading cause of embolic CVA Associated with increased risk for heart failure and all cause mortality

Work-Up CXR EKG TSH CMP CBC Troponin Echo

Management The first step is to determine whether the patient is stable or not Look for any hemodynamic instability such as hypotension, elevated heart rate, fevers Is the patient responsive? Are there any MS changes? Is the patient symptomatic or asymptomatic?

Rate versus Rhythm Control There is no clear survival benefit in rate versus rhythm control

Rate-Control Strategy Try rate control first for patients with persistent AF: Over 65 With CAD With contraindications to antiarrhythmic drugs Unsuitable for cardioversion Without CHF

Rhythm-Control Strategy Try rhythm-control first for patients with persistent AF Who are symptomatic Who are younger Presenting for the first time with lone AF Secondary to a treated/corrected precipitant With CHF

Treatment Options Patients with PAF can be highly symptomatic: Three main aims of treatment for PAF are to… Suppress paroxysms of AF and maintain NSR Control HR during PAF Prevent complications Treatment strategies include out-of-hospital initiation of antiarrhythmic drugs approach Patients with PAF carry the same risks of stroke and thromboembolism as those with persistent AF

Acute-Onset AF Acute-onset AF requires immediate hospitalization and urgent intervention Those at highest risk have a ventricular rate greater than 150 BPM, ongoing symptoms of chest pain, dizziness, syncope, or critical perfusion

Classification of AF Initial event symptomaticMay or may not asymptomaticreoccur Onset unknown Paroxysmal spontaneous terminationrecurrent <7 days & most often <48hrs Persistent Not self-terminating recurrent Lasting >7 days or prior cardioversion Permanent Not terminated established Terminated but relapsed no cardioversion attempted

Treatment Options Cardioversion: synchronized (w/QRS) delivery of current to heart; depolarizes tissue in a reentrant circuit; afib involves more cardiac tissue Antiarrhythmics: amiodarone, sotalol (Betapace), multaq (dronedarone), Rythmol (propafenone), Tikosyn (Dofetilide) AV Nodal blocking agents: Diltiazem, metoprolol Anticoagulation AV Nodal Ablation

Considerations before Cardioversion if onset is within last hours, may be able to arrange cardioversion—use heparin around procedure Need TEE if valvular disease, duration >48hrs (or high risk of thrombus) prior to cardioversion If unable to definitely conclude onset of AF in last hours: need 4-6 weeks of anticoagulation prior to cardioversion, and warfarin for 4-12 weeks after

Cardioversion Cardioversion is performed as part of a rhythm-control treatment strategy There are two types of cardioversion: electrical (ECV) and pharmacological (PCV) Cardioversion of AF is associated with increased risk of stroke in the absence of antithrombotic therapy Not all attempts at ECV or PCV are successful Patient choice is important

Atrial fibrillation--management Rate control with chronic anticoagulation is recommended for first line approach for majority of patients; overall Afib is a stable rhythm Beta-blockers (propanolol and metoprolol) or Non- dihydropyridine calcium channel blockers (verapamil or diltiazem) recommended. Digoxin not recommended for rate control Anticoagulation: low molecular weight heparin and then warfarin; can use aspirin for anticoagulation if contraindication to warfarin, but not as effective

The Aim of Heart Rate Control Minimize symptoms associated with excessive heart rates Prevent tachycardia-associated cardiomyopathy Digoxin monotherapy should be only used for older, sedentary patients Perform a risk-benefit assessment to inform the decision of whether or not to give antithrombotic therapy

CHADS2 Score for Atrial Fibrillation Stroke Risk Congestive Heart Failure Yes +1 Hypertension History Yes +1 Age >75 Yes +1 Diabetes Mellitus History Yes +1 Stroke Symptoms previously or TIA? Yes +2

Recommendations for Anticoagulations ScoreRiskAnticoagulation Therapy Considerations 0LowAspirinAspirin daily 1ModerateAspirin or WarfarinAspirin daily or raise INR to , depending on factors such as patient preferenceINR 2 or greaterModerate or High WarfarinRaise INR to , unless contraindicated (e.g. clinically significant GI bleeding, inability to obtain regular INR screening)INR

CHADS2-VASC CHF/LV dysfunction HTN Age >75 DM Stroke/TIA Vascular disease Age Female

HAS-BLED HTN Abnormal renal/liver fx CVA Bleeding Labile INR’s Elderly >65 Drugs or alcohol use 1 1 or or 2

Coumadin (Warfarin) MOA: Vitamin K antagonist Half life: hrs, peak effect hrs Until recently was one of the most efficacious treatment for stroke prevention Difficult to keep INR at a therapeutic range

Dabigatran (Pradaxa) MOA- direct thrombin inhibitor(anti-IIa) Half-life hrs with nml CrCl >80mL/min; if CrCl <30 ~27 hrs Peak effect- 2-3 hrs No routine laboratory testing is needed Dosing mg BID Renal dosing CrCl 15-30: 75mg BID, CrCl <15 not defined To convert from warfarin, start when INR <2, to convert from parenteral anticoagulant start 0-2 hr before next scheduled parenteral dose

Rivaroxaban (Xarelto) MOA- Direct factor Xa inhibitor Half-life-9-12 hrs; 9-13 hrs in elderly and those with CKD Time to peak effect hrs Dosing-20mg once daily with food (activity lower if fasting) -15mg once daily if CrCL=30-49mL/min -10mg once daily for DVT prevention

Apixaban (Eliquis) MOA-Direct factor Xa inhibitor Half-life-2hrs time to peak effect 3 hrs Dosing-5mg twice daily -2mg twice daily for high risk (ARI)

ASA + Clopidogrel Not indicated for anticoagulation for stroke prevention

Atrial fibrillation--management Goal INR of 2.5 ( ) with coumadin Rhythm control---second line approach, if unable to control rate or pt with persistent sxs Can also consider radiofrequency ablation at pulmonary veins

Follow-Up and Referral Follow-up after cardioversion should take place at 1 month, and the frequency of subsequent reviews should be tailored to the patient Reassess the need for anticoagulation at each review Referral for further specialist intervention should be considered in patients… In whom pharmacological therapy has failed With lone AF With EKG evidence of any underlying electrophysiological disorder

Atrial Flutter Atrial rate /min Sawtooth pattern in II, III, AVF Usually 2:1 or higher AV block Normal QRS

Atrial Flutter- causes and associations Atrial stretch, fibrosis, scarring Often seen with sinus node dysfunction Often seen with atrial fibrillation Same factors seen in atrial fibrillation

Atrial Flutter-assessment H & P—assess heart rate, sxs of SOB, chest pain, edema (signs of failure) If unstable, need to cardiovert Echocardiogram to evaluate valvular and overall function Check TSH Assess onset of sxs—in the last hours? Sudden onset? Or no sxs?

Atrial flutter-management Control ventricular rate (beta blockers, calcium channel blockers) Cardioversion Anticoagulation as with atrial fibrillation Ablations

Diagnostic Testing for Arrhythmias TSH Electrolytes Cardiac enzymes Hemodynamics Echocardiogram Cardiac catheterization Electrophysiology studies

CASE STUDY #1 77 year old female who presented to the emergency room with acute shortness of breath and chest discomfort She has a history of prior CVA, HTN, Hypothyroidism, Dyslipidemia, GERD Medications: Simvastatin, Aspirin, Lisinopril, Omeprazole WHAT SHOULD BE DONE NEXT?

Diagnostics? Electrocardiogram Cardiac enzymes TSH BMP, CBC Urinalysis CXR

ECG INTERPRETATION Rate Regular or irregular….P waves? QRS wide or narrow?

Results/ECG interpretation Troponin 0.06 with nml CK, MB, RI Nml BMP, TSH WBC 11.2 UA positive for leukocytes, WBC, nitrates CXR nml ECG…..??? VS: temp 37.9, HR 125bpm, BP 136/82, RR 22, no audible heart murmur

Management of AF 3 main objectives Rate control Prevention of thromboembolism Correction of rhythm disturbance if indicated

Treatment Options? Rate control versus antiarrhythmic? What do you think? Anticoagulation? What is her CHAD2 Score Safety and monitoring? Other necessary testing?

CHADS2 Score 4

Continued…. Duration of time in atrial fibrillation appears to be less than 48hrs Given her age we could try converting with an amiodarone drip Options for AC….coumadin versus another anticoagulant…if indicated Further work up should include an echocardiogram and possibly a nuclear stress test

Results/ECG Interpretation K+ 4.3, Mg 2.1, CK 124, MB 3.7, Troponin 0.23 WBC 11, BUN 21, Cr 1.4 TSH.67 BNP 146 CXR mild CHF ECG ??? VS: 98/62, 132, 32, oxygenating 97% on 2L

QUESTIONS??

References Hebbar, A. Kesh and William J. Hueston, M.D. “Management of Common Arrhythmias: Part I Supraventricular Arrhythmias,” Am Fam Physician 2002; 65: Hebbar, A. Kesh and William J. Hueston, M.D. “Management of Common Arrythmias Part II: Ventricular Arrythmias and Arrhythmias in Special Populations,” Am Fam Physician 2002; 65: Tallia, Alfred et al. “Swanson’s Family Practice Review” Fifth Edition, Mosby, Inc. 2005, pp ABFM In-Training Exam 2002, 2003.

Multaq (Dronedarone) Indicated for patients with a recent episode of non valvular paroxysmal or persistent atrial fibrillation or atrial flutter and is in a NSR or will be cardioverted Contraindicated in HYHA Class IV CHF, recent decompensated HF, Heart blocks, bradycardia, QTc >500ms or PR >280ms, severe hepatic impairment and pregnancy