SHA24/012001

Devices for Control of Atrial Fibrillation

Joseph G Akar, MD, PhD Associate Professor of Medicine Director, Cardiac Electrophysiology Laboratory

AF in Heart Failure

All-cause mortality by baseline atrial fibrillation

Mortality following new onset AF in patients with sinus rhythm at baseline

Eur Heart J 2005; 26:1303-1308

Atrial Fibrillation and Heart Failure: The age-old question

AF

CHF

Principles of Management

1

2

3

Circulation 2012;125:945-957

Principles of Rate Control in AF: The Good, The Bad, the and Ugly

Principles of Rate Control for AF •The Good: Beta Blockers •Improve HF morbidity and mortality •Prevent SCD in HF •Rate control prevents LVEF deterioration •Cannot use in decompensated HF

•The Bad: Digoxin •Very poor rate control agent •Does not improve AF •Risk of toxicity •Positive inotropic effect N Engl J Med 2008;358:2667-77

•The Ugly: AVJ ablation/permanent pacer •Excellent in rate control •Risk of pacemaker/pacemaker dependency •Risk of HF

MOST Trial

MOST Trial

MADIT II Trial

DAVID Trial

Attempt to reduce RV pacing as best possible, however 100% pacing may not be avoidable such as in cases of AVJ ablation for control of AF

The Dilemma of Ablate and Pace AF may prevent HF response to pacing BUT Controlling AF by pacing may worsen HF

Ablate and Pace

AF

CHF

Ablate and Pace

AF

CHF

AF

CRT

CHF

Does controlling AF by pacing worsen HF?

Medical Management vs AVJ Ablation/RV pacing

Change in LVEF

Chattejee NA et al. Circulation: Arrhythmia and Electrophysiology. 2012; 5: 68-76

Medical Management vs AVJ Ablation/CRT

All-cause mortality

Cardiovascular mortality

Ganesan AN et al. J Am Coll Cardiol. 2012;59(8):719-726

Conclusions •Ablate and pace is more effective that pharmacological therapy for control of AF •Controlling AF by AVJ ablation/pacing does not worsen HF •In patients with normal LVEF, it is reasonable to attempt RV pacing only but keep a close eye on the LVEF •In patients with LV dysfunction it is more prudent to use CRT

Does AF Worsen the Response to CRT

AF during CRT causes: •Irregular heart rate •Fusion/pseudofusion •Fast uncontrolled heart rate

Mechanisms of Dyssynchrony in Heart Failure

•Atrioventricular dyssynchrony •Interventricular dyssynchrony •Intraventricular dyssynchrony

Summary of Proposed Mechanisms Cardiac Resynchronization

Intraventricular Synchrony

↑ dP/dt, ↑ EF, ↑ CO (↑ Pulse Pressure) ↓ LVESV

Atrioventricular Synchrony

↓ MR

↓ LA ↑ LV Diastolic Pressure Filling

↓ LVEDV

Reverse Remodeling Yu C-M, Chau E, Sanderson J, et al. Circulation 2002;105:438-445

Interventricular Synchrony

↑ RV Stroke Volume

Proposed Mechanisms: Improved Atrioventricular Synchrony Improved Atrioventricular Synchrony

AF

Optimized AV Delay: ↓ Isovolumic Contraction Time1,2

↓ MR

1,4

↓ LA1 Pressure

↑ LV Diastolic Filling1,3

↓ LVEDV1,4

Yu C-M et al. Circulation 2002;105:438-445 2 Kindermann M et al. Pacing Clin Electrophysiol 1997; 20(I):2453-2462 3 Breithardt O et al. Am Heart J 2002;143:34-44 4 Søgaard P et al. Cardiology 2001;95:173-182 1

Does AF affect CRT?

All cause mortality

Higher mortality in AF patients with CRT did not reach significance

Upadhyay GA et al. J Am Coll Cardiol 2008; 52: 1247-1249

Does AF affect CRT? LVEF

AF: 25.3% to 35.2%

NSR: 24.6% to 33.8% P<0.001

* Calculation method of LVEF was not uniformly reported Upadhyay GA et al. J Am Coll Cardiol 2008; 52: 1247-1249

Does AF affect CRT? NYHA

Patients with AF showed slightly less functional improvement compared to SR (0.84), but was still significant

Upadhyay GA et al. J Am Coll Cardiol 2008; 52: 1247-1249

Does AF affect CRT? Functional Outcomes

6MWD 11.6 m

MLWHF

Upadhyay GA et al. J Am Coll Cardiol 2008; 52: 1247-1249

Conclusions

•The presence of AF does not fully negate CRT response in patients who are otherwise candidates, but may affect mortality benefit •Functional improvement in response to CRT may be diminished due to AF •Patients with AF undergoing CRT must be closely monitored for maximal BiV pacing

Management of AF and CRT Effect of maximizing BiV pacing

Koplan BA et al. J Am Coll Cardiol 2009; 53: 355-360

Management of AF and CRT

Gasparini M et al. Eur Heart J 2008; 29:1644-1652

AF ablation in Heart Failure •Case-control study: 58 pts with CHF (class II-IV) and LVEF < 45% underwent AF ablation •Control group: 58 patients matched for age, sex, AF classification •91% with persistent/permanent AF •Mean LVEF improved 21±13% •Greatest improvement (24±8%) in pts with no structural disease and high rates (tachyinduced)

Hsu L-F et al, N Engl J Med 2004; 351:2373-83

AF Ablation vs AVJ ablation + CRT in CHF

N Engl J Med 2008; 359: 1778-85

Conclusions

•AF control is very important especially in setting of CHF •AVJ/pacer is more effective than pharmacological therapy •Strongly consider CRT for patients with LV dysfunction undergoing AVJ ablation •Strongly consider AVJ ablation for CRT patients with uncontrolled AF •Consider AF ablation for rhythm control when suitable