“Lone” Atrial Fibrillation: Lifestyle Management and Hybrid Procedures

[In addition], new mapping systems have been created, allowing doctors to image the heart in new ways and consider the exact mechanisms that start and sustain AF. Some of these systems use special multielectrode catheters deployed inside the heart, while newer ones will allow for similar information to be gathered in an entirely noninvasive way.

In between catheter ablation and the Cox-Maze procedure, various treatment options exist, including combinations of technologies known as “hybrid” or “convergent” procedures and less-invasive versions of a Cox-Maze procedure. Each treatment option has its own risks and recovery times. The success rates for these procedures vary widely, largely due to patient-specific factors and operator skill and experience.

[Editor’s note: One of these less invasive procedures is the Wolf Mini-Maze. Dr Wolf performed the first of these in 2003 at the University of Cincinnati in Ohio. In a 2014 paper published in the Annals of Cardiothoracic Surgery, he reported results of a review of patients aged 15 to 87 years who had undergone the procedure 1 to 9 years earlier.¹⁰ No deaths were noted, and AF-free rates were as follows: 92% for paroxysmal AF; 85% for persistent AF; and 75% for long-standing persistent AF.]

Dr Wolf: The Wolf Mini-Maze is a video-assisted procedure in which small incisions are made between the ribs on each side of the chest and a bipolar radiofrequency clamp is used to isolate the pulmonary veins. The second part of the procedure is exclusion of the left atrial appendage, which is the source of blood clots in the majority of AF-related strokes. This often eliminates the need for anticoagulants — which reduce stroke risk by 60% to 70%¹¹ and can be very expensive to both the patient and the healthcare system. Of course, the cost of stroke is astronomical, and AF strokes tend to be large strokes. If we can eliminate AF strokes, patients and families will benefit and the healthcare system savings would be substantial.

Left atrial appendage (LAA) closure also increases the AF-free rate because in some subsets of patients the abnormal electrical circuit includes the LAA. Closure of the LAA can terminate AF. One reason for the high success rate of the Wolf Mini-Maze is that we close the LAA in every case, and in the third part of the procedure, the ganglionic plexi are tested and, if positive, ablated.

Future Directions

Cardiology Advisor: What should be next steps in terms of research and development in this area?

Dr Cuculich: There remains much to learn about the reasons why AF develops, and the field is rapidly progressing to address these questions. Perhaps the most important clinical step forward will come when we have better ways to characterize a patient’s specific type of AF. For example, presently we describe AF as paroxysmal, persistent, or permanent. This is a poor way to characterize any disease. Once we can harness the patient-specific complexities of AF, such as risk factors, genetics, location of AF triggers, mechanisms of sustaining AF, and heart size and shape, then we can begin to tailor a treatment plan that matches up precisely for that patient. 

Dr Michos: We need more data about what motivates individuals for long-lasting behavioral and lifestyle changes. Motivations for behavioral change likely vary by age, sex, socioeconomic status, and other important key demographics, as it is too simplistic to think one size or one strategy will fit all. We need to understand drivers of behavioral change.

Dr Wolf: We need to develop a better understanding of the underlying mechanisms in AF, as well as improved technology — we need better catheters, which might improve ablation success rates. In addition, as it often runs in families, we need to know more about the genetics of AF so we can predict who will and will not develop this debilitating condition. 

Reference

1. US Centers for Disease Control and Prevention. Arial Fibrillation Fact Sheet. https://www.cdc.gov/dhdsp/data_statistics/fact_sheets/fs_atrial_fibrillation.htm. Updated August 22, 2017. Accessed October 9, 2017.
2. Staerk L, Sherer JA, Ko D, Benjamin EJ, Helm RH. Atrial fibrillation: epidemiology, pathophysiology, and clinical outcomes. Circ Res. 2017;120(9):1501-1517.
3. Pison L, Hocini M, Potpara TS, et al; Scientific Initiative Committee, EHRA. Work-up and management of lone atrial fibrillation: results of the European Heart Rhythm Association Survey. Europace. 2014;16(10):1521-1523.
4. Wyse DG, Van Gelder IC, Ellinor PT, et al. Lone atrial fibrillation: does it exist? A “white paper” of the Journal of the American College of Cardiology. J Am Coll Cardiol. 2014;63(17):1715-1723.
5. Ganesan AN, Shipp NJ, Brooks AG, et al. Long-term outcomes of catheter ablation of atrial fibrillation: a systematic review and meta-analysis. J Am Heart Assoc. 2013;2(2):e004549. 
6. Jacobs V, May HT, Bair TL, et al. Long-term aspirin does not lower risk of stroke and increases bleeding risk in low-risk atrial fibrillation ablation patients [published online September 26, 2017]. J Cardiovasc Electrophysiol. doi:10.1111/jce.13327
7. Wyse DG, Waldo AL, DiMarco JP, et al; Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) Investigators. A comparison of rate control and rhythm control in patients with atrial fibrillation. N Engl J Med. 2002;347(23):1825-1833.
8. Pathak RK, Middeldorp ME, Meredith M, et al. Long-term effect of goal-directed weight management in an atrial fibrillation cohort: a long-term follow-up study (LEGACY). J Am Coll Cardiol. 2015;65(20):2159-2169.
9. Mozaffarian D, Furberg CD, Psaty BM, Siscovick D. Physical activity and incidence of atrial fibrillation in older adults: the Cardiovascular Health Study. Circulation. 2008;118(8):800-807.
10. Wolf RK. Treatment of lone atrial fibrillation: minimally invasive pulmonary vein isolation, partial cardiac denervation and excision of the left atrial appendage. Ann Cardiothorac Surg. 2014;3(1):98-104.
11. Diener H-C, Weber R, Lip GYH, Hohnloser SH. Stroke prevention in atrial fibrillation: do we still need warfarin? Curr Opin Neurol. 2012;25(1):27-35.