Cardiac Electrophysiology

Lecture 7 Feb 27, 2018

Tamara Langeberg, CNP Minneapolis Heart Institute Cardiac Electrophysiology February 27, 2018

Disclosures

• None

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Objectives

• Rhythm identification – Identify indications for cardiac monitoring – Identify appropriate cardiac monitor to use • Devices (pacemaker, defibrillator, biventricular pacemaker, LINQ, Micra, Watchman) – Understand indications for device placement – Understand the importance of anticoagulation needs pre and post procedure • Cardioversions – Improve understanding of cardioversion procedure – Update anticoagulation recommendations pre/post cardioversion procedure • Ablations

Cardiac Electrophysiology

• Rhythm identification – Monitoring options • Devices (pacemaker, defibrillator, biventricular pacemaker, LINQ, Micra, Watchman) • Cardioversions • Ablations

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Break Down on Indications for Patient Monitoring

• Arrhythmia Identification/Burden – Correlation of symptoms and arrhythmia – Rhythm identification for best management – Arrhythmia burden • Including post ablation and risk stratification for anticoagulation • Cryptogenic stroke (ESUS) • Syncope, unexplained

Monitors

• Options: – Holter Monitor – External Loop Recorder (Event monitor) – Patch Monitor – APP – Implantable Loop Recorder

• Choice of monitoring used is based on: – Frequency of patient symptoms, events – Indication for monitoring (syncope, arrhythmia burden, symptoms vs no symptoms, etc.) – Patient and provider preference

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Holter Monitor

• Symptoms frequent enough to be detected within 24–72 hours of monitoring

• Most effective if patients are able to record a diary to correlate symptoms/events with possible arrhythmia.

• 24‐hour ambulatory monitoring – ~25 to 50% will experience a symptom • 2‐15% will correlate with causal arrhythmia • 35% will not be associated with arrhythmia

Event Monitor (external loop monitor)

• Symptoms that are likely to occur within 1–4 week period of time

• Patients with abrupt syncope may have limited findings due to lack of patient activation – if cardiac arrhythmia is etiology of event, then device auto‐trigger criteria should correlate with time of patient event

• Extended monitoring increases symptom detection – ~50% at 3days – ~75% at 5‐21 days (mean 9 days)

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Patch Monitor

• Can be considered as an alternative to event monitor (2‐4 weeks)

• Products – typically accurately self‐applied – Water resistant – Have been considered more comfortable and less cumbersome than an event monitor – Limited to 1 lead view • Holter/Event monitors have at least 3, up to 12 leads

There’s an App for That

• >90% of American adults own a cell phone (349.9 million in U.S.) – 81% are a smartphone – 648,000,000 minutes are spent each month on Facebook!

• Healthcare systems and providers have been slow to adopt EMRs and integrate medical data with mobile devices

• Alivecor and ECG Check systems are FDA approved – Single bipolar lead (lead I) ECG monitoring systems that snaps on the back of a smartphone – Finger contact on the case of the smartphone activates ECG recording – Data is transmitted to the smartphone from the case using frequency modulation of an ultrasound or Bluetooth signal – Can be viewed in real‐time – Can be transmitted to a secure server for the patient’s provider to review in PDF format. – The system has been validated in a number of settings, including event monitoring and screening of atrial fibrillation

https://doi.org/10.1161/CIRCULATIONAHA.114.009024 Circulation. 2014;130:573‐581 Originally published August 11, 2014

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Implantable Loop Recorder

• Symptoms occur less than once per month (recurrent, infrequent) • Cryptogenic stroke – Crystal AF trial with average of 84 days to detection of afib post cryptogenic stroke • Unexplained syncope • Suspected atypical reflex syncope with or without structural heart disease – Example: malignant vasovagal with severe cardio‐inhibition • PICTURE registry (largest study that ILR placed for syncope) – 570 patients followed for at least 1 year or until syncopal event (mean of 10 +/‐ 6 months). – Found that syncopal event directly contributed to a diagnosis in 78% of patients. • A cardiac etiology was found in 75% of those patients

Atrial Fibrillation

Term Definition •AF that terminates spontaneously or with Paroxysmal AF intervention within 7 d of onset.•Episodes may recur with variable frequency. Persistent AF •Continuous AF that is sustained >7 d. Long‐standing persistent AF •Continuous AF >12 mo in duration. •The term “permanent AF” is used when the patient and clinician make a joint decision to stop further attempts to restore and/or maintain sinus rhythm.•Acceptance of AF represents a therapeutic attitude on the part Permanent AF of the patient and clinician rather than an inherent pathophysiological attribute of AF.•Acceptance of AF may change as symptoms, efficacy of therapeutic interventions, and patient and clinician preferences evolve. •AF in the absence of rheumatic mitral Nonvalvular AF stenosis, a mechanical or bioprosthetic heart valve, or mitral valve repair.

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Not Atrial Fibrillation…

• Atrial Flutter – typical, atypical, right‐sided, left‐sided

Supraventricular Tachycardia

• Atrial Tachycardia – ‐left and/or right sided

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More SVT….

• WPW, accessory pathway, AV node re‐entry tachycardia

Cardiac Electrophysiology

• Rhythm identification – Monitoring options • Devices (pacemaker, defibrillator, biventricular pacemaker, Micra, Watchman) • Cardioversions • Ablations

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Indications

• Pacemaker – Symptomatic bradycardia (sinus node or AV nodal disease) • Micra Pacemaker – Symptomatic bradycardia in patient with AV nodal disease, typically chronic atrial fibrillation, high infection risk • Defibrillator – Primary vs Secondary prevention of sudden cardiac death (SCD) • Biventricular (pacemaker or defibrillator) – Re‐synchronization of ventricles to reduce CHF symptoms/hospitalizations and improve LV function • Watchman Device –newest technology in EP – Alternative approach to long‐term a/c for patients at high cardio‐embolic event risk and bleed risk

Device Options and Leads Used

• Pacemakers: – Dual chamber (atrial AND ventricular) – Single chamber (atrial OR ventricular) – Biventricular (CRT‐P) – Micra • Defibrillators: – Dual chamber (atrial AND ventricular) – Single chamber (ventricular ONLY) • Shocking atrium would cardiovert atrium, shocking ventricle defibrillates ventricle – Subcutaneous (single lead, no pacing) – Biventricular (CRT‐D) • Watchman (Left Atrial Appendage Occlusion) Device

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What Does a Generator Look Like

Leads……. Where and What’s the Difference

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Pacemaker / ICD

Micra Pacemaker

• Pacemaker placed percutaneously directly into the right ventricle • Does not require the use of leads • patient’s age and medical condition may influence the selection of the Micra pacing system • Patient selection: – Patient would benefit from a single chamber pacemaker system – when placement of a traditional system is difficult

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Subcutaneous Implantable Cardioverter Defibrillator (SQ-ICD)

• Used in patients: – who are candidates for ICD insertion on the basis of current guidelines – who do not have symptomatic bradycardia or spontaneous, recurring ventricular tachycardia (VT) that is reliably terminated with anti‐ tachycardia pacing – Who may have vascular access challenges – Who may be high risk for blood infections

New Technologies - EP

• Patients are candidates for Watchman device if:

– a CHA2DS2‐VASc score of ≥ 3 AND – Non‐valvular atrial fibrillation AND – Have an appropriate reason to seek a non‐drug alternative to anticoagulation AND – suitable for Warfarin therapy short term

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Device Placement

• Considered a minimally invasive procedure

• Local anesthesia and conscious sedation

• Pre‐op antibiotics used (80% reduced infection risk)

• Transvenous lead placement using subclavian vein, cephalic vein, or axillary vein

• Generator placed subcutaneously in the infraclavicular region

• ICDs typically undergo Defibrillation Threshold Test (DFTs) – Demonstrates safety margin in the event ICD shock needed

• Coronary sinus lead: – <5% unable to place transvenously – placed surgically using a mini‐thoracotomy (cardiac surgeon)

• Closed with dissolvable sutures (internal), steri‐strips or dermabond (over incision) and silverlon dressing (band‐aide with antimicrobial properties)

Pre/Post-Device Anticoagulation

Lead Extraction Pacemaker Devices Defibrillators

Warfarin Pre‐procedure Goal INR

Restart the evening post Restart the evening post Restart Warfarin the evening post procedure unless otherwise procedure unless otherwise Post‐procedure procedure recommended by EP MD recommended by EP MD

Heparin No heparin products for 6 hours No heparin products for 6 hours No heparin products for 6 hours Pre‐procedure prior to procedure prior to procedure prior to procedure

Ideally no heparin products post Ideally no heparin products post Ideally no heparin products post procedure, but if needed, restart procedure, but if needed, restart procedure, but if needed, restart IV heparin post procedure based IV heparin post procedure based IV heparin post procedure based Post‐procedure on EP MD recommendations. on EP MD recommendations. on EP MD recommendations.

Lovenox None unless EP MD recommends None unless EP MD recommends None unless EP MD recommends

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Intermediate Risk Procedure

• Devices are considered a simple procedure with intermediate bleed risk, but never without any risk……

Cardiac Electrophysiology

• Rhythm identification – Monitoring options • Devices (pacemaker, defibrillator, biventricular pacemaker, LINQ, Micra, Watchman) • Cardioversions • Ablations

©AllinaHealthSystem Lecture 7 Feb 27, 2018

Goal of Cardioversion…. How?

• Simple definition: – Convert the patient back to a normal rhythm.

• Chemical: use of medications – corvert, Dofetilide, Flecainide, Propafanone, amiodarone, quinidine…..

• Direct Current: electrical shock – Causes depolarization of cardiac cells and allows the sinus node to take back over

Cardioversion Procedure Risks

• Sun burn from patches/energy

• Bite tongue

• Obesity – Increased tissue to penetrate, airway obstructs easier

• Stroke/TIA: embolic – Highest risk in 48 hours following the procedure – Ongoing risk in first month post cardioversion (motion of muscle is not synchronous)

Pearls

• Nothing by mouth for 8 hours prior to procedure

• Must have a driver with them and someone to stay with them for at least 24 hours (Allina policy).

• We use propofol for sedation – patient wakes up asking when we are going to start. Literally out for ~3‐5 minutes.

• Therapeutic anticoagulation……

Anticoagulation

• Warfarin with INR >2.0 or on DOAC for at least 21 consecutive days prior to procedure. – Day zero starts with first therapeutic INR or first dose of DOAC

• If sub‐therapeutic anticoagulation (INR <2.0 or missed/not on Novel agent 21 consecutive days), then patient will need TEE guided cardioversion. – If thrombus seen on TEE, then anticoagulation x6 consecutive weeks followed by repeat TEE to document thrombus resolution prior to cardioversion

• If patient presents with clearly defined onset of arrhythmia <48 hours, then DCCV can be performed without TEE.

Wait…there’s more

• Treat with anticoagulation for a minimum of 1 month post cardioversion

• Long‐term anticoagulation per risk stratification using CHA2DS2 VASc score.

• Patients who undergo TEE guided DCCV should be therapeutically anti‐coagulated at the time of TEE guided DCCV. – Therapeutic heparin level and continued until INR >2.0 – Lovenox 1mg/kg SQ Q12h until INR >2.0 – Warfarin with INR >/= 2.0 (for <3 consecutive weeks)

• Fingerstick INR vs Venous draw INR

Cardiac Electrophysiology

• Rhythm identification – Monitoring options • Devices (pacemaker, defibrillator, biventricular pacemaker, LINQ, Micra, Watchman) • Cardioversions • Ablations

Radiofrequency Ablation (RFA)

• Heat energy used alters conductibility of cardiovascular tissue. • SVT – Arrhythmia triggered using pacing and proarrhythmia medication (isuprel) – Mapping techniques used to locate origin of arrhythmia • Atrial Fibrillation – CT or MRI imaging used to create a 3D view of heart and associated structures (pulmonary veins, esophagus) • Procedure duration 3‐4 hours – depending on arrhythmia origin and # of sites • Use MAC (conscious sedation) vs general anesthesia depending on procedure complexity – Sedation can inhibit our ability to trigger the arrhythmia

Ablation Images

Anticoagulation

Persistent Atrial SVT Fib/flutter Paroxysmal Afib/flutter

Goal INR 2‐3 for 3 weeks prior to Goal INR 2‐3.0 depending on Warfarin Pre‐procedure None needed procedure CHADS score

Therapeutic INR not necessary. Goal INR 2‐2.5 TEE if INR <2 in 3 Hold warfarin 3 days prior. +/‐ Day of Procedure None needed weeks prior to procedure TEE if in afib/flutter

Continue x8 weeks, then Continue x8 weeks, then Post‐procedure None needed depending on CHADS2 score depending on CHADS2 score

No heparin products (IV or SQ) for No heparin products (IV or SQ) for Heparin Pre‐procedure None needed 6 hours prior to procedure. 6 hours prior to procedure.

If needed, based on EP MD If needed, based on EP MD Post‐procedure recommendations. recommendations.

Based on EP MD Based on EP MD recommendations when INR <2.0, recommendations when INR <2.0, Lovenox Post‐procedure None needed 1/2 dose Q12hours 1/2 dose Q12hours

Ablation Procedure Risks

• Damage to normal conduction – Resulting in need for pacemaker placement • Cardiac perforation/tamponade – Requiring pericardial drain placement • Femoral access site bleeding, infection – Rarely can have pseudo aneurysm (less common in venous access sites) • Esophageal Perforation/Ulceration – Life threatening (50% mortality risk)

• US Dairy Council: “7% of American adults believe chocolate milk comes from brown cows” = 16.4 mil Americans