Implantable Monitoring Systems Vs Wearables: When & How Suneet Mittal, MD Director, Electrophysiology Director, The Snyder Center for Comprehensive Atrial Fibrillation Director, Cardiac Research www.valleymedicalgroup.com/EP February 21, 2019 Disclosures: Consultant to Abbott, Boston Scientific, and Medtronic WESTERN AF 2019 PROGRAM @drsuneet  CARDIAC RESYNCHRONIZATION THERAPY 2017:  BUILDING A PROGRAM TO GET ALL PATIENTS SUCCESSFULLY TO THE FINISH LINE 

Lifecycle of AF Patients Diagnosis and Monitoring Stroke Prevention Treatment Drugs Devices Ablation Risk Factor Modification

4.6 Million Tests Annually ECG Monitoring Tools ILR ~100,000 MCT Monitors ~400,000 4.6 Million Tests Annually 1.4 Billion USD Holter Monitor ~2.8 Million Event Monitor ~1.3 Million

ECG Monitoring Tools Lead Based (1-Piece) Smartphone Event Recorder Scottcare– TeleSense, TeleSentry Spectacor – Pocket ECG TeleRhythmics – Heartrak TCAT Smartphone (e.g., Alivecor) Event Recorder Spot Single-Lead ECG Check Smartwatch (e.g., Kardiaband) Holter Holter Monitoring (1-2 days) Holter Monitoring (1-2 weeks) Lead Based (e.g., CardioKey) (e.g., Zio) (e.g., ePatch) Patch Based Lead Based (2-Piece) Applied Cardiac Systems – CORE Biomedsys – TruVue Infobionic – MoMe Kardia Lifewatch – ACT Elite Medicomp – Duet Mobile Telemetry Monitoring (Up to 30 days) Lead Based (e.g., multiple; Telesense) (e.g., SEEQ, Body Guardian) Patch Based Garment Based (e.g., nECG) Patch Based Biotelemetry – MCOT Patch Lifewatch – ECG mini Medicomp – TelePatch Medtronic – SEEQ Nuubo - nECG Preventice – Body Guardian Implantable Loop Recorder (Up to 3 years) Mittal S et al. JACC 2011; 58: 1741-1749; Mittal S. CIR 2017; 25: 12-16; Lee RJ, Mittal S. Heart Rhythm 2018

Case Presentation 50-year old female with hypertension and Sjogren's syndrome reports a several year complaint of palpitations associated with light-headedness. Episodes occur every few weeks and last 5-10 minutes. There has been no ECG documentation obtained during her typical episode. Her baseline ECG and echocardiogram are entirely normal. She presents for further evaluation CHA2DS2-VASc =2 (if she had atrial fibrillation).

Smartphone Based Diagnosis Cheap Owned by the patient Real time Long term High fidelity recordings No intermediary between patient and doctor

Smartphone ECG Monitoring: Potential Applications Diagnose etiology of unexplained palpitations In patients with known paroxysmal atrial fibrillation, Assess heart rate in sinus rhythm vs. atrial fibrillation Assess relationship between symptoms and recurrence of atrial fibrillation in patients being treated with anti-arrhythmic drugs and/or catheter ablation In patients with persistent atrial fibrillation, Daily objective self monitoring for exclusion of arrhythmia recurrence

Case Presentation 74-year-old male with hypertension and remote history of SVT ablation. A year and a half ago, he had a stress echocardiogram. He exercised for 6 ½ minutes on a Bruce protocol. The exam was normal. He recently noticed that his heart rate was elevated while at the gym. He had no symptoms referable to a rate. An ECG demonstrated atrial fibrillation with rapid ventricular response. An echocardiogram demonstrated a left atrial diameter of 3.7 cm, left atrial volume index of 31.2 mL/m², a 4.4 cm aortic root, and an ejection fraction of 30%. He was referred for evaluation; an ECG showed sinus rhythm. (CHA2DS2-VASc = 2)

Case Presentation

Duration vs. Burden JAMA Cardiology 2018

Duration vs. Burden JAMA Cardiology 2018

mSToPS Trial Steinhubl SR et al. JAMA 2018; 320: 146-155

Smartwatches for AF Detection Bumgarner JM et al. JACC 2018 71 (21): 2381-2388

Smartwatch Photoplethysmography Coupled with a Deep Neural Network Tison GH et al JAMA Cardiology 2018; 3 (5): 409-416

Smartwatches for AF Detection

How Well Do These Devices Perform? Implantable Loop Recorder Longest ≥2 min ≥6 min ≥10 min ≥30 min ≥1 hour Episode PPV (%) PPV excellent for AF episodes > 1 hour, irrespective of population being evaluated Imperfect assessment of AF burden: atrial and ventricular ectopy; atrial tachycardia Mittal S. et al. Heart Rhythm 2016; 13: 1624–1630 

ILR Guided Anticoagulation Post-AF Ablation REACT.COM n=59 94% reduction in the time on NOAC compared to chronic anticoagulation No strokes or deaths Passman R et al. JCE 2016

Which AECG Monitor for Which Patient? Indication for Monitoring Rationale Strength Limitations Caveats / Potential Alternatives Suspected AF (e.g., cryptogenic stroke) 30% AHRE detection over 3-years Higher AHRE detection than conventional follow-up PPV for AHREs < 1 hour is sub-optimal   Clinical significance of AHREs < 24 hours is uncertain If only AHREs > 24 hours are clinically significant, daily ECG monitoring with a smartphone sufficient.

Which AECG Monitor for Which Patient? Indication for Monitoring Rationale Strength Limitations Caveats / Potential Alternatives Known AF Establish AF pattern Differentiating pattern of AF is important when choosing medical and ablation options Continuous ECG monitoring can perfectly distinguish patterns of AF Impractical to implant a device for this sole purpose Daily ECG monitoring with a smartphone sufficient to exclude persistent AF Assess efficacy To compare the effectiveness of different AF management strategies, important to know with uncertainty whether AF has or has not been eliminated Continuous ECG monitoring is the best available tool to capture information about all recurrences of AF; information about AF duration and burden is available   High NPV but only modest PPV AF burden can be overestimated (false positive classification due to sinus arrhythmia, atrial and ventricular ectopy) None; in foreseeable future, ILRs will remain the best available technology for this purpose. Ideally suited to measure efficacy in ongoing clinical trials

Which AECG Monitor for Which Patient? Indication for Monitoring Rationale Strength Limitations Caveats / Potential Alternatives Guide management “Pill-in-the-pocket” anticoagulation Following a successful ablation procedure, many patients ask to discontinue anticoagulation, irrespective of their CHA2DS2-VASc score. Three pilot studies have shown anticoagulation can be withheld following ablation if there are no AHREs > 1 hour   The PPV for AHREs < 1 hour is sub-optimal. Current technology not robust enough to ensure 100% connectivity Establishing infrastructure to respond to all recurrences of AF in patients is difficult Wearables – incorporation of an ECG monitor within a wearable (watch) may alert the patient about significant recurrences of AF

Implantables vs. Wearables General Population High Risk Asymptomatic Symptomatic Initial Diagnosis Ongoing Management 10 Million 4.5 Million Abnormal ECG Palpitations 1 Million Post-Ischemic Stroke AF Management Adapted from iRhythm Investors Call Jan 2019