Question 1 - ICD in LV dysfunction with AF ?

AF underestimated as cause of cardiomyopathy

The first arrhythmia where T-CMP was described (1913), but not what usually comes to mind
May be related to rate
But may also be related to irregularity of rhythm and other factors (AF-CMP)

Ling et al.(2012) Irregular rhythm adversely influences calcium handling in ventricular myocardium: implications for the interaction between heart failure and atrial fibrillation. Circ Heart Fail 5:786–793

Redfield … Ellenbogen K.A.(2000) Tachycardia-related cardiomyopathy: a common cause of ventricular dysfunction in patients with atrial fibrillation referred for atrioventricular ablation. Mayo Clin Proc 75:790–795.

Prabhu … Peter Kistler (2017) Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Systolic Dysfunction: The CAMERA-MRI Study. J Am Coll Cardiol 70:1949–1961

How to identify those who will improve

Rate may not predict reversibility
LVEF not different
BNP levels not different
Smaller LV dimension. LVEDD < 66

Fujino et al. Characteristics of congestive heart failure accompanied by atrial fibrillation with special reference to tachycardia-induced cardiomyopathy. Circ J. 2007 Jun;71(6):936-40.

Prabhu … Peter Kistler (2017) Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Systolic Dysfunction: The CAMERA-MRI Study. J Am Coll Cardiol 70:1949–1961

Summary

Consider T-CMP / AF-CMP
Attempt rhythm control when possible
LV dimension / scar may help predict reversibility

Question 2 - ICD in Irreversible LV dysfunction with AF ?

Higher mortality and more appropriate shocks with AF

Mustafa et al. Atrial Fibrillation Is Associated With Higher Overall Mortality in Patients With Implantable Cardioverter‐Defibrillator: A Systematic Review and Meta‐Analysis. https://doi.org/10.1161/JAHA.118.010156 JAHA. 2018;7

Survival improvement with ICD versus medical management in presence of AF ?

Risk markers in ICD patients

Ilan Goldenberg et al. Risk Stratification for Primary Implantation of a Cardioverter-Defibrillator in Patients With Ischemic Left Ventricular Dysfunction, JACC 2008 Volume 51, Issue 3,Pages 288-296,https://doi.org/10.1016/j.jacc.2007.08.058

Summary

Patients with AF may benefit less from ICD
Worse overall prognosis
Consider possible benefit from ICD based on presence of other risk markers

Question 3 - Which ICD in paroxysmal AF - Single chamber or dual chamber ?

Dual chamber may have better detection

Friedman et al. Dual-Chamber Versus Single-Chamber Detection Enhancements for Implantable Defibrillator Rhythm Diagnosis. The Detect Supraventricular Tachycardia Study. Circulation. 2006;113:2871–2879. https://doi.org/10.1161/CIRCULATIONAHA.105.594531

Difference is small in real world

Atrial sensing problems may contribute to inappropriate detection in dual chamber devices
Improved algorithms with single chamber devices
Better understanding of device programming - less inappropriate therapies

Zeitler et al. Single vs. dual chamber implantable cardioverter-defibrillators or programming of implantable cardioverter-defibrillators in patients without a bradycardia pacing indication: systematic review and meta-analysis, EP Europace 2018;20(10):1621–1629, https://doi.org/10.1093/europace/euy183

Dual chamber ICD to reduce AF episodes and to identify silent AF

Atrial pacing to reduce AF ?

About 50% of patients develop AF during lifespan of device (1)
In a randomized study, significant reduction in AF burden with AF prevention and termination therapies

Schmitt C, Montero M, Melichercik J. Significance of supraventricular tachyarrhythmias in patients with implanted pacing cardioverter defibrillators. Pacing Clin Electrophysiol. 1998;295:302.
Friedman PA, Dijkman B, Warman EN, et al. for the Worldwide Jewel AF Investigators. Atrial therapies reduce atrial arrhythmia burden in defibrillator patients. Circulation. 2001;104:1023–1028

Dx ICD - Avoid problems with atrial lead, but reap benefits of atrial signal ?

Summary

Dual chamber device with atrial pacing may reduce occurrence of AF
Atrial sensing may help in identification of silent AF
But whether any of these contributes to an improvement in outcomes is questionable and not proven
Additional atrial lead adds some morbidity

To wrap up …

In patients with AF and LV dysfunction, consider AF-CMP. Rhythm control and reassessment of EF when possible. MRI scar and LV volumes may identify reversibility.
Patients with AF in general are a subset with a higher mortality and smaller likely benefit from ICD.
Atrial sensing capability with dedicated lead or floating bipole may result in small reduction in inappropriate therapies and identify silent AF
Dual chamber devices with atrial pacing therapies to prevent AF may reduced AF episodes
But whether these result in any improvement in outcomes is not clear