***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: BACKGROUND To assess the effects of comprehensive cardiac rehabilitation compared with usual care on physical activity and mental health for patients treated with catheter ablation for atrial fibrillation . METHODS The patients were r and omized 1:1 stratified by paroxysmal or persistent atrial fibrillation and sex to cardiac rehabilitation consisting of 12 weeks physical exercise and four psycho-educational consultations plus usual care ( cardiac rehabilitation group ) versus usual care . The primary outcome was Vo2 peak . The secondary outcome was self-rated mental health measured by the Short Form-36 question naire . Exploratory outcomes were collected . RESULTS 210 patients were included ( mean age : 59 years , 74 % men ) , 72 % had paroxysmal atrial fibrillation prior to ablation . Compared with usual care , the cardiac rehabilitation group had a beneficial effect on Vo2 peak at four months ( 24.3mL kg-1 min-1 versus 20.7mL kg-1 min-1 , p of main effect=0.003 , p of interaction between time and intervention=0.020 ) . No significant difference between groups on Short Form-36 was found ( 53.8 versus 51.9 points , P=.20 ) . Two serious adverse events ( atrial fibrillation in relation to physical exercise and death unrelated to rehabilitation ) occurred in the cardiac rehabilitation group versus one in the usual care group ( death unrelated to intervention ) ( P=.56 ) . In the cardiac rehabilitation group 16 patients versus 7 in the usual care group reported non-serious adverse events ( P=.047 ) . CONCLUSION Comprehensive cardiac rehabilitation had a positive effect on physical capacity compared with usual care , but not on mental health .  Cardiac rehabilitation caused more non-serious adverse events Background Natural history of paroxysmal atrial fibrillation ( AF ) is not very well documented . Clinical experience suggests that paroxysmal AF could progress to chronic AF with estimates ranging between 15 and 30 % over a period of 1–3 years . We performed an epidemiologic study to eluci date the natural history of paroxysmal AF , this study estimated its incidence in a general practice setting , identified associated factors and analyzed the progression into chronic AF as well as the mortality rate . Methods Using the UK General Practice Research Data base ( GPRD ) , we identified patients aged 40–89 years with a first-recorded episode of paroxysmal AF during 1996 .  Risk factors were assessed using 525 incident paroxysmal AF cases confirmed by the general practitioner ( GP ) and a r and om sample of controls . We follow-up paroxysmal AF patients and estimated their mortality rate and progression to chronic AF . Results The incidence of paroxysmal AF was 1.0 per 1,000 person-years . Major risk factors for paroxysmal AF were age and prior valvular heart disease , ischaemic heart disease , heart failure and hyperthyroidism . During a mean follow-up of 2.7 years , 70 of 418 paroxysmal AF patients with complete information progressed to chronic AF . Risk factors associated with progression were valvular heart disease ( OR 2.7 , 95 % CI 1.2–6.0 ) and moderate to high alcohol consumption ( OR 3.0 , 95 % CI 1.1–8.0 ) . Paroxysmal AF patients did not carry an increased risk of mortality , compared to an age and sex matched sample of the general population . There was a suggestion of a small increased risk among patients progressing to chronic AF ( RR 1.5 , 96 % CI 0.8–2.9 ) . Conclusion Paroxysmal AF is a common arrhythmia in the general practice setting , increasing with age and commonly associated with other heart diseases . It sometimes is the initial presentation and then progress to chronic AF . A history of valvular heart disease and alcohol consumption are associated with this progression Aims This prospect i ve pilot- study was performed to assess whether regular moderate physical activity elevates the parasympathetic tone to the atrio-ventricular node and decreases VR during permanent AF . Background Adequate ventricular rate ( VR ) control in patients with permanent atrial fibrillation ( AF ) is not easy to accomplish . Methods 10 patients ( mean age 59 ± 10 years ) with permanent AF ( duration : 10 ± 8 years )  underwent moderate physical exercise adjusted to their individual physical capability ( 45 min walking/jogging twice a week ) . To analyze VR control physical exercise tests and Holter-ECG recordings  were performed before and after 4 months . In addition , stepwise lactate tests and psycho-pathometric examinations were obtained . Results After 4 months of training , there was a trend toward a decrease of mean VR in 24 h Holter-ECGs by 12 % from 76 ± 20 to 67 ± 12 bpm ( P = 0.05 ) while there was no significant decrease of the minimal VR ( 38 ± 8 vs. 36.3 ± 4.5 bpm , P = 0.54 ) . At a lactate threshold of 2 mmol/l there was a trend towards an increase of the running speed from 105 ± 11 to 116 ± 12 m/min ( P = 0.05 ) . A significant VR decrease of 8 % ( range 5–10 % ) was observed at almost all exercise levels during exercise treadmill testing . Increases of exercise capacity and decreases of VR were accompanied by subjective improvements of health perception . Conclusion Regular moderate physical activity  decreases VR at rest and during exercise while increasing exercise capacity . Physical training should be taken into account for ventricular rate control during AF AIMS The management of patients with atrial fibrillation ( AF ) is often inadequate due to deficient adherence to the guidelines . A nurse-led AF clinic providing integrated chronic care to improve guideline adherence and activate patients in their role , may effectively reduce morbidity and mortality but such care has not been tested in a large r and omized trial . Therefore , we performed a r and omized clinical trial to compare the AF clinic with routine clinical care in patients with AF . METHODS AND RESULTS We r and omly assigned 712 patients with AF to nurse-led care and usual care . Nurse-led care consisted of guidelines based , software supported integrated chronic care supervised by a cardiologist . The primary endpoint was a composite of cardiovascular hospitalization and cardiovascular death . Duration of follow-up was at least 12 months . Adherence to guideline recommendations was significantly better in the nurse-led care group . After a mean of 22 months , the primary endpoint occurred in 14.3 % of 356 patients of the nurse-led care group compared with 20.8 % of 356 patients receiving usual care [ hazard ratio : 0.65 ; 95 % confidence interval ( CI ) 0.45 - 0.93 ; P= 0.017 ] . Cardiovascular death occurred in 1.1 % in the nurse-led care vs. 3.9 % in the usual care group ( hazard ratio : 0.28 ; 95 % CI : 0.09 - 0.85 ; P= 0.025 ) . Cardiovascular hospitalization amounted ( 13.5 vs. 19.1 % , respectively , hazard ratio : 0.66 ; 95 % CI : 0.46 - 0.96 , P= 0.029 ) . CONCLUSION Nurse-led care of patients with AF is superior to usual care provided by a cardiologist in terms of cardiovascular hospitalizations and cardiovascular mortality . Trial registration information : Clinical trials.gov identifier number : NCT00391872 PURPOSE A r and omized study was conducted to determine whether short-term exercise training in patients with chronic atrial fibrillation ( AF ) might improve exercise capacity and quality of life ( QOL ) , and influence atrioventricular conduction . METHODS Atrial fibrillation patients ( age 64 + /- 7 years ) were r and omized to exercise training  ( n = 15 ) or a 2-month control period ( n = 15 ) followed by the training program . Twenty-four training sessions consisted of aerobic exercise and muscle strengthening . A cycle ergometer test and a 15-minute resting high-frequency spectral electrocardiogram analysis were performed and a QOL question naire ( SF-36 ) was completed before and after training . Because there were no changes after 2 months in the control group , pooled data for all patients are presented before and after training . RESULTS Cumulated work at Borg scale 17 increased by 41 % + /- 36 % . Heart rate at rest and after 10 minutes of exercise decreased from 75 + /- 14 to 68 + /- 14 bpm and 145 + /- 19 to 137 + /- 21 bpm , respectively . HF increased from 81 + /- 17 to 91 + /- 22 milliseconds . Four of the 8 scales and 1 of the 2 summary scales of the Short-Form-36 improved . P < .05 for all results . CONCLUSIONS Exercise capacity , heart rate variability , and QOL improved after 2 months of exercise training  in patients with chronic AF .  Heart rates at rest and during exercise decreased Background Surprisingly little information on symptoms of paroxysmal atrial fibrillation is available in scientific literature . Using question naires , we have analyzed the symptoms associated with arrhythmia attacks . Methods One hundred r and omly-selected patients with idiopathic paroxysmal atrial fibrillation filled in a structured question naire . Results Psychic stress was the most common factor triggering arrhythmia ( 54 % ) , followed by physical exertion ( 42 % ) , tiredness ( 41 % ) coffee ( 25 % ) and infections ( 22 % ) . Thirty-four patients cited alcohol , 26 in the form of red wine , 16 as white wine and 26 as spirits . Among these 34 , red wine and spirits produced significantly more episodes of arrhythmia than white wine ( p = 0.01 and 0.005 respectively).Symptoms during arrhythmia were palpitations while exerting ( 88 % ) , reduced physical ability ( 87 % ) , palpitations at rest ( 86 % ) , shortage of breath during exertion ( 70 % ) and anxiety ( 59 % ) . Significant differences between sexes were noted regarding swollen legs ( women 21 % , men 6 % , p = 0.027 ) , nausea ( women 36 % , men 13 % , p = 0.012 ) and anxiety ( females 79 % , males 51 % , p = 0.014 ) . Conclusion Psychic stress was the commonest triggering factor in hospitalized patients with paroxysmal atrial fibrillation .  Red wine and spirits were more proarrhythmic than white wine . Symptoms in women in connection with attacks of arrhythmia vary somewhat from those in men Background — Exercise training is an effective treatment for important atrial fibrillation ( AF ) comorbidities . However , a high level of endurance exercise is associated with an increased AF prevalence . We assessed the effects of aerobic interval training ( AIT ) on time in AF , AF symptoms , cardiovascular health , and quality of life in AF patients . Methods and Results — Fifty-one patients with nonpermanent AF were r and omized to AIT ( n=26 ) consisting of four 4-minute intervals at 85 % to 95 % of peak heart rate 3 times a week for 12 weeks or to a control group ( n=25 ) continuing their regular exercise habits . An implanted loop recorder measured time in AF continuously from 4 weeks before to 4 weeks after the intervention period . Cardiac function , peak oxygen uptake ( O2peak ) , lipid status , quality of life , and AF symptoms were evaluated before and after the 12-week intervention period . Mean time in AF increased from 10.4 % to 14.6 % in the control group and was reduced from 8.1 % to 4.8 % in the exercise group ( P=0.001 between groups ) . AF symptom frequency ( P=0.006 ) and AF symptom severity ( P=0.009 ) were reduced after AIT . AIT improved O2peak , left atrial and ventricular ejection fraction , quality -of-life measures of general health and vitality , and lipid values compared with the control group . There was a trend toward fewer cardioversions and hospital admissions after AIT . Conclusions — AIT for 12 weeks reduces the time in AF in patients with nonpermanent AF . This is followed by a significant improvement in AF symptoms , O2peak , left atrial and ventricular function , lipid levels , and QoL. Clinical Trial Registration — URL : http://www . clinical trials.gov . Unique identifier : NCT01325675 BACKGROUND A r and omised study was conducted to determine if short-term exercise training in patients with chronic atrial fibrillation ( AF ) might improve symptoms and health-related quality of life ( HRQoL ) . METHODS AF patients ( 64+/-7 years ) were r and omised to exercise training  ( n=15 ) or a 2-month control period  ( n=15 ) followed by an exercise training program ( ETP ) . The ETP consisted of 24 training sessions with aerobic exercise and muscle strengthening . A cycle ergometer test , with recording of perceived exertion on the Borg scale , was performed . The participants completed HRQoL question naires , the Short-Form 36 ( SF-36 ) and Symptom and Severity Checklist ( SSCL ) , before and after training . Because there were no changes after two months in 
    Output:
    
Due to few r and omised patients and outcomes , we could not evaluate the real impact of exercise-based cardiac rehabilitation  on mortality or serious adverse events .
The evidence showed no clinical ly relevant effect on health-related quality of life .
Pooled data showed a positive effect on the surrogate outcome of physical exercise capacity , but due to the low number of patients and the moderate to very low- quality of the underpinning evidence , we could not be certain of the magnitude of the effect .