Paroxysmal, Persistent, or Permanent Atrial Fibrillation: Is “Prevention” the New “P”?

Atrial fibrillation (AF) continues to be a growing public health concern as the incidence of AF admissions and Medicare claims continues to climb. Treatment options have focused on two different paths: rhythm control versus rate control. In addition, oral anticoagulation is prescribed based on the patient’s associated risk for stroke. Control of symptoms, limiting complications, and preventing stroke are the primary goals of treatment.

Treatment choices include rate-slowing medications, rhythm control medications, oral anticoagulants, and ablation procedures. These options can be thought of as “tools in the toolbox” that can be brought out and advised for the appropriate patient based on symptoms and comorbidities. The American College of Cardiology, American Heart Association, and Heart Rhythm Society have updated AF guidelines to reflect the multitude of management options.¹ 

AF occurs when cardiac properties induce abnormal electrical impulses in the atrium. Myocardial fibrosis, inflammation, dilation, ischemia and infiltrations can all play a role in the development of AF. The pathophysiology likely indicates multiple disease processes, and research continues in order to more fully understand these complexities. Known comorbidities that increase the incidence of AF include hypertension, diabetes mellitus, sleep apnea, alcohol use, and obesity.² 

Patients may be medically naïve when first diagnosed with AF. This diagnosis often serves as a wake-up call to previously under-recognized or under-treated medical conditions. Patients may ask what else they can do to control their disease process. Clinicians historically have advised heart-healthy behaviors; however, until recently there was not significant evidence of lifestyle benefit in AF management. 

ARREST-AF

Recent exciting evidence has been presented that demonstrates control of certain risk factors can influence AF outcomes. Australian researchers Pathak et al published the ARREST-AF study, reporting that aggressively controlled risk factors improved success rates of AF ablation.³ Patients with a body mass index (BMI) >27 kg/m², who were scheduled to undergo AF radiofrequency ablation and had one or more risk factors, were offered an aggressive risk factor reduction protocol. Risk factors included hypertension, glucose intolerance/diabetes, hyperlipidemia, and obstructive sleep apnea. Patients who accepted this strategy made up the intervention group (n=61); those who declined were followed as the control group (n=88). 

Risk factor modification (RFM) patients participated in risk reduction clinics every three months. Blood pressure (BP) was measured three times daily through a home monitor. Lifestyle modifications included restricting dietary salt. BP was managed with angiotensin-converting enzyme (ACE) inhibitors and other agents as necessary to keep target BPs less than 130/80 at least 80% of the time. Echocardiograms were assessed to observe for left ventricular hypertrophy. 

Weight management was directed using a motivational/goal-oriented counseling approach. Meal plans and behavioral modification, along with food and exercise diaries, were used. If the goal weight loss was not met using these measures after three months, a very low-calorie meal replacement regimen was used for one to two meals per day. Goals were set to reduce body weight by 10%. Once the initial goal was met, patients were transitioned to calorie-controlled, low-glycemic, high-protein foods. The target BMI for the intervention group was less than or equal to 25 kg/m². Exercise was prescribed for 20 minutes three times weekly, increasing to moderate-intensity activity 200 minutes weekly. 

Other risk factors that were monitored included lipids and elevated blood glucoses. Lifestyle modifications were employed first, followed by statin medications for hyperlipidemia. Fibrates were added if triglycerides were elevated. Metformin was used if the hemoglobin A1C was not less than 6.5% with lifestyle modifications. 

The ARREST-AF research team also managed sleep-disordered breathing, smoking, and alcohol use. Diagnosed sleep apnea was treated with positional therapy as well as continuous positive airway pressure. Smoking cessation support clinics were utilized. Counseling and assistance were arranged with a goal of alcohol use less than or equal to 30 grams per week. 

The control group patients (who declined the intensive RFM clinic) were given information regarding risk factor reduction, but treatment was at their personal physician’s discretion. Mean duration of time prior to ablation was 9.8 + 7.1 months for the RFM group and 10.2 + 9.2 months for the control group. Both groups then underwent pulmonary vein isolation with the endpoint described as electrical isolation. Further lesions were added if the patient had AF episodes greater than 48 hours or if the left atrial size was greater than 57 millimeters. If AF recurred after the three-month blanking period, a second ablation was prescribed. 

The results of this single-center observational study showed that patients in the risk factor group had statistically significant greater weight loss, lower BP, better glycemic control, and improved lipid profiles. In addition, symptoms in the RFM group were improved when compared to the control group. Arrhythmia-free survival with both single and multiple ablation procedures was higher in the RFM group when compared with controls. The researchers summarized that a structured clinic approach to control risk factors for AF resulted in significant improvement in AF outcomes. Clearly, when motivated patients are provided with tools for self-improvement, optimal outcomes occur. 

The ARREST-AF results demonstrate that focusing on the cause of AF is an important concept in population health management. Although the complex causes of AF continue to be explored, there is no doubt that certain risk factors can contribute to AF events and treatment outcomes. The health care team can educate patients as a first step to empower and engage in self care. As in most chronic disease processes, a definitive “cure” for AF remains elusive. Ablation procedures and medical treatments are effective, but the rate of AF recurrence remains high. By providing patients with definitive tools to modify the risk factors of AF, further successful control of symptoms and the disease process could be realized.³ 

Specialty Clinic Concept

What is the best approach to promote lifestyle and risk factor management? Losing weight and lowering blood pressure can certainly be difficult tasks and not feasibly accomplished in a 15-minute office visit. Talking about change is easy, but actually finding the tools for success is much more elusive. Looking at the successes of other disease-management programs, such as heart failure clinics and cardiac rehabilitation programs, some practitioners are exploring the concept of AF clinics. Hendriks et al first reported a successful program where a nurse-led clinic, using computer support software, demonstrated better adherence to AF guidelines. Importantly, patients in this randomized controlled trial who were managed via the AF clinic had a death rate of 1.1% versus the usual care group death rate of 3.9% (hazard ratio: 0.28; 95% CI: 0.09-0.85; P=0.025).⁴ More recently, Stewart et al reported the SAFETY trial, which examined a post discharge AF management program with interventions including a home visit, Holter monitoring, and multidisciplinary support. The intervention group demonstrated more days out of the hospital and alive when compared to the control group with routine care.⁵

AF patients require coordinated care and treatment. Control of symptoms, protection from stroke, and limitation of complications such as tachycardia-induced cardiomyopathy or heart failure are important goals of treatment. In our experience, atrial fibrillation care at Lancaster General Health in Lancaster, Pennsylvania has transitioned to an outpatient focus whenever possible. Therefore, an AF clinic staffed by electrophysiology nurse practitioners provides longitudinal follow-up of the AF patient. Early one-week follow-up post hospitalization, ECG monitoring, assessment of medication tolerance, and management of risk factors are key components of the clinic workflow. Although start-up of the outpatient clinic is in the early stages, multidisciplinary coordination with our electrophysiologists, bariatric program, and sleep specialists adds to the comprehensive approach. We focus on AF education to empower patients in management of self-care with a prevention approach. Early experiences confirm that patients appreciate the clinic format to help navigate the various AF treatments. Early identification of problems, concerns, and reinforcing the many educational topics, allow for a comprehensive approach to heart rhythm care. Plans are being developed for registry data collection in order to monitor outcomes and analyze treatment approaches along with risk factor management effects.

Conclusion

Specialty care clinics have been proposed as a strategy toward enhanced population health management. Coordinating guideline-directed medical therapy and procedures, along with upstream prevention care to impact the AF substrate, will be an important need as AF incidence grows. The diagnosis of AF can be overwhelming and stressful to the patient — there is much to learn and manage. Healthcare providers are familiar with the “P’s” of atrial fibrillation to describe the duration of the rhythm: paroxysmal, persistent, and permanent. We should now be discussing the new “P” with our patients: prevention. Comprehensive patient understanding of multiple medications, anticoagulation strategies, and procedure options continues to be the cornerstone of AF care; however, to truly provide state-of-the-art treatment, we need to add a new “tool in the toolbox.” Assisting our patients to control the risk factors of AF through weight loss, treatment of sleep apnea, glycemic/ lipid/hypertension control, reduction of alcohol use, and stress management can improve patient outcomes. The “cure” for AF has remained elusive; however, a comprehensive care approach impacting the AF physiologic substrate holds incredible promise as a preventive treatment. 

References

1. January CT, Wann LS, Alpert JS, et al. 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: executive summary. J Am Coll Cardiol. 2014;64(21):2246-2280. doi: 10.1016/j.jacc.2014.03.021.
2. Abed HS, Wittert GA, Leong DP, et al. Effect of weight reduction and cardiometabolic risk factor management on symptom burden and severity in patients with atrial fibrillation: a randomized clinical trial. JAMA. 2013;310(19):2050-2060. doi: 10.1001/jama.2013.280521.
3. Pathak RK, Middeldorp ME, Lau DH, et al. Aggressive risk factor reduction study for atrial fibrillation and implications for the outcome of ablation: the ARREST-AF cohort study. J Am Coll Cardiol. 2014;64:2222-2231.
4. Hendriks JM, de Wit R, Crijns HJ, et al. Nurse-led care vs. usual care for patients with atrial fibrillation: results of a randomized trial of integrated chronic care vs. routine clinical care in ambulatory patients with atrial fibrillation. Eur Heart J. 2012;33(21):2692-2699. doi: 10.1093/eurheart/ehs071.
5. Stewart S, Ball J, Horowitz JD, et al. Standard versus atrial fibrillation-specific management strategy (SAFETY) to reduce recurrent admission and prolong survival: pragmatic, multicentre, randomised controlled trial. Lancet. 2014 Nov 17. doi: 10.1016/S0140-6736(14)61992-9.