What s new in my specialty? Jon Melman, MD Heart Rhythm Specialists McKay-Dee Hospital some would say some would say my specialty 1
some would say my specialty First pacemaker 1958 some would say my specialty First pacemaker 1958 First ICD 1980 some would say my specialty First pacemaker 1958 First ICD 1980 First ABIM boards 1992 2
some would say my specialty First pacemaker 1958 First ICD 1980 First ABIM boards 1992 First RF ablation 1994 Electrophyisology: Continues to expand in scope and therapies Study of cardiac arrhythmias Medical management of arrhythmias Electrophyisology: Continues to expand in scope and therapies Study of cardiac arrhythmias Medical management Pacemaker placement 3
Electrophyisology: Continues to expand in scope and therapies Study of cardiac arrhythmias Medical management Pacemaker placement ICD implantation Electrophyisology: Continues to expand in scope and therapies Study of cardiac arrhythmias Medical management Pacemaker placement ICD implantation Implantable loop recorders Electrophyisology: Continues to expand in scope and therapies Study of cardiac arrhythmias Medical management Pacemaker placement ICD implantation Implantable loop recorders Catheter ablation 4
Electrophyisology: Continues to expand in scope and therapies Study of cardiac arrhythmias Medical management Pacemaker placement ICD implantation Implantable loop recorders Catheter ablation Hereditary and genetic arrhythmias LQTS, HCM, ARVC, myotonic dystrophy, CPVT, etc Catheter Ablation in Electrophysiology: Pre-RF First performed using DC shocks for AV node ablation (1981) RF Catheter ablation in electrophysiology First RF performed 1994 Localized application of RF energy Minimal surrounding tissue damage Highly effective for ablation 5
RF ablation: a Controlled form of electrosurgery Fluoroscopy: Traditional imaging modality Lateral RA Tricuspid annulus X-ray based imaging Useful for imaging heart in real-time Ablation catheter Coronary sinus Can be difficult to precisely keep track of catheter location during prolonged/complex ablations Electroanatomic mapping Localizes the catheter in three dimensions Allows marked reduction in X-ray use Fluoroscopy-free ablations now being performed 6
Using a mapping system to track catheters and make a map of the heart Using a mapping system to track catheters and make a map of the heart Using a mapping system to track catheters and make a map of the heart 7
Propagation map showing atrial flutter Cavotricuspid isthmus ablating along the line.. How effective is RF ablation? Arrhythmia Acute Success Rates Complication Rates AVNRT 95-99% 2-5% WPW/AVRT 90%-98.5% 2-3% Atrial flutter 95%-100% 3.2% Atrial Tachycardia 90%-98.5% PVCs/Idiopathic VT ~50%-95% 2-5% Atrial fibrillation 40-80% Ischemic VT 30-90% 8
Importance of atrial fibrillation Most common arrhythmia seen in clinical practice Patient symptoms: Irregularity in rhythm Loss of atrial kick : ~30% of LV filling at baseline, more with structural heart disease Tachycardia and tachycardia-mediated cardiomyopathy Some patients completely asymptomatic Stroke risk: 15% of all strokes in US 36% of strokes in individuals above age 80 20% of cryptogenic stroke Am J Med 2014 127 e15-e16 What is atrial fibrillation? Chaotic fibrillatory activity in the atrium Irregularly irregular ventricular rhythm Unpredictable/difficult to control rate What is atrial fibrillation? Irregularly Irregular Disorganized atrial activity 9
Treatment of atrial fibrillation: Rhythm or rate control? Rate control: control the rate with an AV nodal blocker i.e. beta blocker, calcium channel blocker, digoxin Rhythm control: Antiarrhythmic drugs, catheter ablation Class IA, IC, III antiarrhythmics Catheter ablation Treatment of atrial fibrillation: Rhythm or rate control? AFFIRM trial: are rate and rhythm control equal? 4060 patients Average age 70 (pts all had to be over 65 y/o with at least one other risk factor) Randomized to rate control (digoxin, beta and/or CCB) or: Rhythm control (30% on amiodarone, 31% on sotalol 15% crossed over to rhythm control due to symptoms, 38% crossed to rate control due to failure of rhythm control 10
Established the standard of care as a choice of rate versus rhythm control But. Are these results applicable to other AF patient populations? Do the results apply to all AF patients uniformly? Follow up: on-treatment analysis Cox proportional hazard model applied to AFFIRM data Increased mortality if: Unable to maintain sinus rhythm On an antiarrhythmic drug NO patients under 60 with LOW stroke risk Effects of AF maintenance over decades of life not well understood 11
323 patients with symptomatic AF (40% persistent) 72% arrhythmia free off AADs at 2 years 15% controlled AF on antiarrhythmic drugs 13% recurred 12
Patients with EF <35%, persistent AF randomized to rate control vs catheter ablation Primary outcome : changein VO2 max 13
Patients with EF 40% or less, NYHA Class II-III and symptomatic, drug-resistant AF Randomized to PVI or up-front AVN ablation with BiVpacing At 6 months: Improved 6-minute walk distance Higher EF (35% vs 28%) How do we ablate atrial fibrillation? No single circuit with an isthmus, location or pathway that terminates atrial fibrillation We target the signals that trigger episodes of atrial fibillation 14
Pulmonary Vein Isolation Durable isolation is the cornerstone of AF ablation Can be performed via RF ablation (point-by-point ablation around the pulmonary veins) Cryoballoon: Balloon is used to occlude PV ostium Freezing is used to isolate the entire vein in one step 15
Most recent trial of AF ablation 127 patients with symptomatic paroxysmal AF, randomized to PVI vs AAD Recurrences monitored by ECG, holter, and/or transtelephonic transmission Excluded patients over 75, EF<40%, LA>5.5cm 16
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Cryoballoon Ablation at McKay-Dee Hospital Catheter Ablation For Paroxysmal AF Pulmonary Vein Isolation with irrigated focal RF ablation catheter Ablation Lesion RF Ablation Catheter 53 Catheter Ablation For Paroxysmal AF Pulmonary Vein Isolation with Arctic Front Advance cryoballoon catheter Ablation Lesion RF Ablation Catheter Cryoballoon Ablation Catheter 54 18
Cryoballoon or Radiofrequency Ablation for Paroxysmal Atrial Fibrillation Secondary outcomes of FIRE and ICE Outcomes of FIRE and ICE Outcome Cryoballoon, RF, N=376, Absolute P N=374, n (%) n (%) difference (%) Rehospitalization for CV cause Rehospitalization for any cause 89 (23.8) 135 (35.9) 12.1 <0.01 Yes 122 (32.6) 156 (41.5) 8.9 <0.01 No Cardioversion 12 (3.2) 24 (6.4) 3.2 0.04 No Repeat ablation 44 (11.8) 70 (17.6) 5.8 0.03 Yes Prespecified 19
RF ablation lesion set Conclusions The EP field is rapidly evolving and expanding with new devices, RF catheter ablation techniques and mapping systems Atrial fibrillation ablation is improving and providing previously symptomatic patients with improved quality of life and better symptom control Cryoballoon ablation at McKay-Dee provides shorter procedure times, decreased incidence of recurrent arrhythmias and rehospitalization The EP service at McKay-Dee is always available for any patient need, inpatient or outpatient and is easily reached on the RAFT hotline 20
Thank you Paroxysmal Atrial Fibrillation AF lasting < 7 days Not requiring cardioversion for termination OR antiarrhthmic drugs to control 21
294 patients with PAF randomized to AAD vs RF PVI, 58 pts underwent a repeat procedure AF recurrence detected by 7 day holter Primary outcome was burden of Afib on Holter Secondary outcome: freedom from afib and freedom from symptomatic Afib At 24 months: 85% of ablation patients were free of atrial fibrillation, 93% free from symptomatic AF (p=0.01 over drug therapy) Despite a 36% crossover from drug to ablation therapy N Engl J Med 2012; 367:1587-1595 146 Patients with symptomatic persistent AF, randomized 2:1 catheter vs AAD Excluded longstanding persistent AF, JCM, EF<30, LA>50mm, prior ablation 22