SHOCK THE VT/ VF PATIENT 1 11/7/2017 SHOCK Is the Unstable - PDF document

11/7/2017 Disclosures • Research Support: NIH, PCORI, Medtronic, Cardiogram Common Heart Rhythms in the • Consulting: InCarda, Johnson & Johnson, Hospital Lifewatch • Equity: InCarda Gregory M Marcus, MD, MAS Associate Professor of Medicine Division of Cardiology University of California, San Francisc Goals of the Talk Tachyarrhythmias- Unstable • Unconscious, altered mental status, • What to do when encountering an SVT ongoing chest pain arrhythmia • “Hypotension” is a clinical judgment • Leveraging the encounter to maximize Atrial fibrillation benefit to the patient long-term AF with WPW SHOCK THE VT/ VF PATIENT 1

11/7/2017 SHOCK “Is the Unstable defibrillator THE SVT, AF, on synch?” VT PATIENT “Is the STILL in SHOCK THE unstable defibrillator PATIENT SVT, AF, on synch?” Anything other than VF  VT MAKE SURE IT IS ON “SYNCH” SHOCK THE PATIENT Tachyarrhythmias-quasi-stable Tachyarrhythmias-quasi-stable Nondihydropyrdine Calcium channel blockers Atrial fibrillation Atrial Fibrillation Diltiazem Verapamil Beta-blockers Metoprolol SVT Atenolol Carvedilol Labetolol Propanolol AF with WPW Blood Pressure 1. Address underlying condition VT 2. Esmolol 3. Digoxin 4. Amiodarone 5. ?Dronaderone? 2

11/7/2017 How about cardioversion? 46 year old man without cardiovascular risk factors and symptomatic AF on propafenone Elective Cardioversion • DC cardioversion is the most efficacious but requires sedation • If the patient has no structural heart disease (no CAD, normal EF, not severe LVH)  200-300 mg of flecainide or 600 mg of propafenone (MUST BE GIVEN WITH AV NODAL BLOCKER DUE RISK OF 1:1 ATRIAL FLUTTER) • Ibutilide IV- Torsades risk, requires 4 hours of monitoring • Tikosyn (dofetilide) can work, but usually in 1-2 days and generally in setting of careful QT monitoring over 3 days 46 year old man without How about cardioversion? cardiovascular risk factors and symptomatic AF on propafenone Elective Cardioversion • A SLOWER FLUTTER PARADOXICALLY CAN RESULT IN A FASTER RHYTHM • Most thrombi in atrial fibrillation arise from the left atrial BECAUSE THE AV NODE CAN appendage ACCOMMODATE A GREATER • Cardioversion can reduce left atrial appendage function PROPORTION OF DEPOLARIZATIONS – Even from AF to sinus • PATIENTS ON FLECAINIDE OR • The pericardioversion period is a particularly pro- PROPAFENONE REALLY SHOULD BE ON thrombotic time AN AV NODAL BLOCKER – Regardless of mode: DC/ electrical, pharmacologic, spontaneous 3

11/7/2017 I decide to go with I decide to go with Elective Elective Cardioversion Cardioversion • Prior to cardioversion: 1, 2 • During and after cardioversion: 1, 2 – Can exclude preexisitng – Anticoagulation for at least 4 weeks thrombus by TEE – Applies even to those who would otherwise not require – Can anticoagulate (therapeutic/ anticoagulation for at least 3 weeks) prior to • Generally does not make sense to cardiovert cardioversion AF in order to avoid anticoagulation 1. JACC 2006;48:e149-246 1. JACC 2006;48:e149-246 2. Chest 2004;126:429S-456 2. Chest 2004;126:429S-456 I decide to go with Bigger Picture on AF THREE GOALS IN Elective Cardioversion TREATING AF IN GENERAL 1. We want to prevent THROMBOEMBOLISM • The magic 48 hours – Must be documented! 2. We want to avoid fast ventricular rates over – Reason to consider starting anticoagulation NOW in the a long period of time to prevent ventricular hospital as it may “stop the clock” myopathy – There are cases of stroke even within this time window, so only do this if you need to and start anticoagulation if you can 3. We want to improve quality of life 4

11/7/2017 We want to prevent Bigger Picture on AF THROMBOEMBOLISM THREE GOALS IN TREATING AF IN GENERAL 1. Atrial fibrillation increases the risk of stroke 1.We want to prevent 5 times 2. 23.5% of all strokes in those age 80-89 are THROMBOEMBOLISM attributed to AF How do we know this? From clinically recognized atrial fibrillation. Wolf et al. Stroke 1991 ATRIAL FIBRILLATION IS Audience Response Question OFTEN ASYMPTOMAIC Among Cryptogenic Stroke Patients, AF can be found in: • 0-3% • 3-10% • 10-20% • 20-30% Page et al. Circulation 1994 5

11/7/2017 We want to prevent AF is common if you look hard enough among cryptogenic stroke patients THROMBOEMBOLISM Brachman et al. Circ A&E 2016 Atrial Fibrillation Predicts a Higher Risk of MI Atrial fibrillation is association with a 30%-40% increased risk of dementia 6

11/7/2017 Atrial Fibrillation is associated with a higher risk of kidney disease How is This Relevant to Hospital Medicine? • That patient who develops atrial fibrillation in the setting of cellulitis or pneumonia • ASSUME YOU WERE LUCKY TO CATCH IT BECAUSE THE PATIENT WAS BEING MONITORED • ANTICOAGULTE UNLESS THERE IS A COMPELLING REASON NOT TO –Examples: »CHADSVASC of 0 or perhaps 1 »History of hemorrhagic stroke Gialdini et al. JAMA 2014 7

11/7/2017 What if I have a suspicion for AF but we don’t catch it? “A patient never calls you in the • Can order a Zio patch (monitors for 1-2 weeks) middle of the night to thank you for not having a stroke.” Injectable Loop Recorder -Michael Ezekowitz, M.B., Ch.B., D.Phil 8

11/7/2017 Atrial fibrillation ablation Audience Response Question The success of a typical atrial flutter ablation is: • 40-50% • 50-70% • 70-95% • Elective, generally takes time to schedule • For SYMPTOMATIC AF- not stroke prevention • 95-100% • Empiric (target PV isolation) • Efficacy ~70% in PAF and ~50% in persistent AF at 1 year, attrition in many over time • Can have early recurrence with long-term success Atrial FLUTTER ablation Tachyarrhythmias-quasi-stable SVT • Quicker procedure, easier to schedule • We have a very clear target • Flutter tends to be more difficult to rate control • Antiarrhythmic drugs do not work so well for flutter • Ablation of atrial flutter is FIRST LINE • Success rate is ~97% 9

11/7/2017 Tachyarrhythmias-quasi-stable Tachyarrhythmias-quasi-stable Vagal Manuevers Vagal Manuevers SVT SVT WA WAIT! • Carotid sinus massage • Valsava • Will terminate ~20% 1 GET A 12 LEAD GET A 12 LEAD ECG! ECG! 1. Lim SH et al. Ann Emerg Med 1998;31:30-35 Tachyarrhythmias-quasi-stable Adenosine SVT • Metabolized by red blood cells and endothelium 75% reduction in ED • Give 6 mg IV with 20 cc flush visits among those • Repeat with 12 mg IV X 2 undergoing catheter • How do I know if I’ve given ablation (p=0.003). enough? 10

11/7/2017 Tachyarrhythmias-quasi-stable The most likely diagnosis is: 1. Ventricular Tachycardia 2. Atrial fibrillation with WPW 3. SVT with aberrancy Tachyarrhythmias-quasi-stable Tachyarrhythmias-quasi-stable Atrial Fibrillation AV nodal blockers with preexcitation Give: Procainamide Ibutilide Then refer to EP for ablation 11

11/7/2017 Tachyarrhythmias-quasi-stable Tachyarrhythmias-quasi-stable Ventricular Ventricular • Scarcity of data • Scarcity of data Tachycardia Tachycardia • Amiodarone probably the most • Consider effective 1,2 -- Lidocaine gtt -- Can cause bradycardia -- Procainamide -- Can hinder EP studies/ ablation - watch for hypotension and Extrapolate from cardiac prolonged QT pulseless VT/ VF versus placebo: 1. Kudenchuck PJ et al. N Engl J Med 1999;341:871-878 versus lidocaine: 2. Dorian P et al. N Engl J Med 2002;346:884-890 Tachyarrhythmias-quasi-stable Tachyarrhythmias- a long QT Ventricular • Get EP involved 1.Electrolytes Tachycardia • May respond to beta-blockers or Hypokalemia calcium channel blockers Hypo-Mg2+ • May be amenable to ablation Hypo-Ca2+ 2. DRUGS 3. Congenital 12

11/7/2017 Tachyarrhythmias Bradyarrhythmias • Important questions: – Is this dynamic/ reversible/ vagal? • IE, more likely benign • IE, less likely respond to pacing • IE, more likely transient THINK ABOUT – Or is this structural TORSADES IF 1. IV magnesium • IE, more likely dangerous AMIODARONE ISN’T • IE, more likely needs pacing 2. Isoproterenol WORKING FOR “VF” • In the absence of SYMPTOMS, type II second 3. Transvenous pacing OR PERHAPS MAKING degree AV block or third degree AV block  THINGS WORSE pacemaker 4. Unstable  DC shock Bradyarrhythmias Short term: + 1. Atropine 1 + 2. Transcutaneous 1 pacing OR Dopamine OR Epinephrine (then mention isoproterenol) 3. Consider consultation ± transvenous pacing 1. AHA Guidelines. Circulation 2010;18:S749 13

11/7/2017 Pacemakers Biventricular Pacemaker • Should be interrogated/ checked every 6 months – Eg, doesn’t necessarily need to be checked while in the hospital • Generally CAN now do MRIs with certain restrictions regarding machine and personnel available • We want to avoid RV pacing – It’s an EP sin to RV pace frequently in anyone with a depressed EF Implantable Cardioverter- His Bundle Pacing Defibrillators • Generally interrogated/ checked every 3 months • All ICDs can also pace • Anti-tachycardia pacing (ATP) is one way to break a VT circuit without pain – But can always accelerate VT or lead to VF • Generally ALSO CAN now do MRIs with certain restrictions regarding machine and personnel available • Trend towards longer delays in detection, allowing faster rates with reduction in inappropriate shocks and DECREASE mortality 14