Description of the condition
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia (irregular heart beat). It affects 1.5% to 2% of the population in Europe and North America (Ball 2013; Camm 2012; Nguyen 2013). The incidence of AF is increasing, mainly due to an ageing population (Ball 2013; Camm 2012; Go 2001; Ruigomez 2005; Stewart 2001). AF is associated with increased mortality, incidence of stroke and other thromboembolic events, and heart failure (Camm 2010; Kirchhof 2007; Stewart 2002). As such, AF has now become a health, social, and economic burden (Brenyo 2011) and is set to worsen over the coming decades (Camm 2012).
Patients with AF can experience palpitations, shortness of breath, fatigue, dizziness, and syncope (fainting) (Camm 2010). An American observational study of 655 individuals found that AF symptoms are a negative predictor for patients' physical capacity (Atwood 2007). Symptoms and duration of AF episodes vary within the individual and from individual to individual (Camm 2010). Five different types of AF exist: first-diagnosed AF, paroxysmal AF, persistent AF, long-standing persistent AF, and permanent AF (Camm 2010). First-diagnosed AF is the term given to the condition when a patient presents with AF for the first time, irrespective of the duration of the arrhythmia or the presence and severity of AF-related symptoms. Paroxysmal AF is self terminating, and usually the rhythm converts spontaneously to sinus rhythm within 48 hours. In persistent AF, the AF episode lasts longer than seven days or requires cardioversion to terminate the episode. When AF duration exceeds one year, AF is considered long-standing persistent. Permanent AF is when AF is accepted without further attempts of conversion, or these attempts have been shown to be unsuccessful or short-lasting (Camm 2010; Lafuente-Lafuente 2012).
Treatment of AF focuses on re-establishing and maintaining sinus rhythm (so-called rhythm control) and protecting the patient against thromboembolic complications (Camm 2010). When AF is longer-lasting (as in persistent AF, long-standing persistent AF and permanent AF) the therapeutic goal is to control the heart rate in the range of 60 to 80 beats/minute at rest and 90 to 115 beats/minute when active (rate control). This is achieved by treatment with antiarrhythmic drugs which block the function of the atrioventricular node (Brenyo 2011; Camm 2010). In addition, treatment should aim at reducing symptoms and discomfort related to AF (Brenyo 2011).
Acute management of patients with AF includes acute conversion to sinus rhythm, protection against thromboembolic events and acute improvement of cardiac function. However, AF recurrence is common despite administration of antiarrhythmic drugs to maintain normal sinus rhythm after cardioversion (Camm 2010).
Radiofrequency ablation is sometimes used to treat AF. It is an invasive treatment developed to cure AF. In a Cochrane systematic review, Chen et al found that ablation has a better effect in inhibiting recurrence of AF compared with medical therapies, but there is limited evidence demonstrating that sinus rhythm is maintained after ablation and after long-term follow-up (Chen 2012). Despite the results of the systematic review, ablation seems to have an increasingly accepted role in the treatment of AF (Brenyo 2011; Calkins 2009; Camm 2010).
Studies have found that quality of life is impaired in individuals with AF compared with healthy controls, the general population, or patients with coronary heart disease in the western world (Dabrowski 2010; Kang 2004; Thrall 2006). Studies have suggested that maintaining sinus rhythm improves quality of life and may be associated with improved survival (Dabrowski 2010; Dorian 2000; Dorian 2002; Kang 2004; McCabe 2011; Thrall 2006). Patients’ lack of self management skills causes distress when trying to handle symptoms of AF such as palpitations, dyspnoea, and fatigue. Seemingly, patients with AF report that they have not received education or help from health professionals regarding how to live with AF (McCabe 2011).
Taken together, the consequences of AF are reduced quality of life and physical capacity, increased healthcare costs, readmission to hospital, loss of income, increased morbidity, and mortality.
Description of the intervention
Cardiac rehabilitation seemingly benefits patients with coronary heart disease and those with heart failure in terms of physical, mental, cognitive, and social function; and a reduction in morbidity, mortality, and healthcare costs (Taylor 2014; Heran 2011; Piepoli 2010).
Cardiac rehabilitation is a comprehensive intervention that includes the components of exercise training, education, psychosocial management, and a behavioural modification programme designed to improve the physical and emotional conditions of patients with heart disease (Piepoli 2010). Cardiac rehabilitation for patients with coronary heart disease can also include patient assessment, nutritional counselling, and risk factor management focusing on lipids, blood pressure, weight, diabetes mellitus, and smoking cessation (Piepoli 2010).
Studies regarding rehabilitation for patients with AF have employed varies training protocols which show the uncertainty as to what kind of physical exercise patients with AF should perform. In a review of 36 studies (of which 6 were randomised controlled trials (RCTs); in total 1512 patients) the following exercise programme was recommended: (1) physical exercise training should include three or more weekly sessions of moderate intensity whole-body aerobic activities (such as walking, jogging, cycling, or rowing); (2) training should include at least 60 minutes per session and continue for a minimum of three months; and (3) physical exercise training sessions should also include segments of stretching, balance exercises, resistance training, and callisthenics (Giacomantonio 2013). Seemingly, the review included studies with a variety of different designs and did not include any rehabilitation components other than exercise training. Further, there was no protocol published before the review was conducted, and risk of bias and risk of random errors were not assessed in trial sequential analyses.
While current recommendations for rehabilitation for patients with coronary heart disease, heart failure and heart valve replacement suggest that a psychosocial or educational support, or both, should be offered (National Board of Health 2013), this has not been explored in patients with AF. A systematic review including 30 studies of mixed designs exploring rehabilitation for patients living with permanent AF, reported that no studies had included psychosocial support or education, or both, with the aim of improving the patient’s self management skills (Lowres 2013).
How the intervention might work
A RCT of 30 patients showed that exercise capacity and heart rate variability improved after two months of exercise training in those with permanent AF (Hegbom 2006; Hegbom 2007). A prospective pilot study of 10 patients, found that regular moderate physical activity among older individuals with AF decreases the ventricular rate at rest and during exercise, while increasing exercise capacity (Plisiene 2008). A prospective study of 20 patients showed that patients' physical capacity increases significantly after physical exercise (a 15% increase measured by VO2 max) (Mertens 1996). In a RCT of 49 patients with permanent AF, Osbak and colleagues concluded that exercise capacity measured by VO2 max improved significantly after 12 weeks of exercise training (Osbak 2011).
In a systematic review, Giacomantonio and colleagues showed that routine moderate intensity physical activity can improve exercise capacity, the capacity to carry out activities of daily living, and overall quality of life for persons living with AF (Giacomantonio 2013).
At the same time a qualitative study concluded that many patients with AF are less likely to perform sports activities because they are afraid to use their body (Hansson 2004).
Possible harmful effects of physical exercise in patients with AF have not been investigated in RCTs but Mertens 1996 found in a small clinical trial that it is safe for patients with permanent AF to participate in exercise training programmes, although patients could experience AF specific adverse events during training, e.g. AF and other arrhythmias (Mertens 1996).
We have not been able to find examples of integrated rehabilitation programmes for patients with AF or guidelines outlining recommendations for rehabilitation for patients with AF, but Hendriks 2012 found in a RCT, that follow-up in a nurse-led AF clinic reduced cardiovascular hospitalisations and mortality significantly compared with usual care. In addition, they found that the AF-related knowledge level was higher in the nurse-led group at one year follow-up compared with the control group that received usual care (Hendriks 2014).
In summary, studies show that exercise training has a positive effect on patients' heart rate and exercise capacity, and quality of life increases after exercise training.
Why it is important to do this review
As described, we find that rehabilitation for patients with AF is an under-researched area and to our knowledge there are no international or national guidelines regarding rehabilitation for patients with AF. Nevertheless, studies suggest that rehabilitation consisting of physical exercise plus a psychoeducational component would increase patients’ physical and mental health.
The benefits and harms of rehabilitation programmes, including an exercise component or a psychoeducational component, or both, for adults with AF are unclear. We have not been able to identify any meta-analysis or systematic reviews that have summarised the evidence in a systematic manner.