human
***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background and Purpose — Cardioembolism in paroxysmal atrial fibrillation ( pxAF ) is a frequent cause of ischemic stroke . Sensitive detection of pxAF after stroke is crucial for adequate secondary stroke prevention ; the optimal diagnostic modality to detect pxAF on stroke units is unknown . We compared 24-hour Holter electrocardiography ( ECG ) with continuous stroke unit ECG monitoring ( CEM ) for pxAF detection . Methods — Patients with acute ischemic stroke or transient ischemic attack were prospect ively enrolled . After a 12-channel ECG on admission , all patients received 24-hour Holter ECG and CEM . Additionally , ECG monitoring data underwent automated analysis using dedicated software to identify pxAF . Patients with a history of atrial fibrillation or with atrial fibrillation on the admission ECG were excluded . Results — Four hundred ninety-six patients ( median age , 69 years ; 61.5 % male ) fulfilled all inclusion criteria ( ischemic stroke : 80.4 % ; transient ischemic attack : 19.6 % ) . Median stroke unit stay lasted 88.8 hours ( interquartile range , 65.0–122.0 ) .  ECG data  for automated CEM analysis were available for a median time of 64.0 hours ( 43.0–89.8 ) . Paroxysmal AF was documented in 41 of 496 patients ( 8.3 % ) . Of these , Holter detected pxAF in 34.1 % ; CEM in 65.9 % ; and automated CEM in 92.7 % . CEM and automated CEM detected significantly more patients with pxAF than Holter ( P<0.001 ) , and automated CEM detected more patients than CEM ( P<0.001 ) . Conclusions — Automated analysis of CEM improves pxAF detection in patients with stroke on stroke units compared with 24-hour Holter ECG . The comparative usefulness of prolonged or repetitive Holter ECG recordings requires further evaluation Aims Uncertainty exists over the importance of device-detected short- duration atrial arrhythmias . Continuous atrial diagnostics , through home monitoring ( HM ) technology ( BIOTRONIK , Berlin , Germany ) , provides a unique opportunity to assess frequency and quantity of atrial fibrillation ( AF ) episodes defined as atrial high-rate events ( AHRE ) . Methods and results Prospect i ve data from 560 heart failure ( HF ) patients ( age 67 ± 10 years , median ejection fraction 27 % ) patients with a cardiac resynchronization therapy ( CRT ) device capable of HM from two multi-centre studies were analysed . Atrial high-rate events burden was defined as the duration of mode switch in a 24-h period with atrial rates of > 180 beats for at least 1 % or total of 14 min per day . The primary endpoint was incidence of a thromboembolic ( TE ) event . Secondary endpoints were cardiovascular death , hospitalization because of AF , or worsening HF . Over a median 370-day follow-up AHRE occurred in 40 % of patients with 11 ( 2 % ) patients developing TE complications and mortality rate of 4.3 % ( 24 deaths , 16 with cardiovascular aetiology ) . Compared with patients without detected AHRE , patients with detected AHRE>3.8 h over a day were nine times more likely to develop TE complications ( P= 0.006 ) . The majority of patients ( 73 % ) did not show a temporal association with the detected atrial episode and their adverse event , with a mean interval of 46.7 ± 71.9 days ( range 0–194 ) before the TE complication . Conclusion In a high-risk cohort of HF patients , device-detected atrial arrhythmias are associated with an increased incidence of TE events . A cut-off point of 3.8 h over 24 h was associated with significant increase in the event rate . Routine assessment of AHRE should be considered with other data when assessing stroke risk and considering anti-coagulation initiation and should also prompt the optimization of cardioprotective HF therapy in CRT patients INTRODUCTION Despite extensive inpatient workup including telemetry monitoring , a significant proportion of stroke is classified as cryptogenic at hospital discharge . It is possible that a significant proportion of cryptogenic stroke is a result of intermittent atrial fibrillation ( AF ) . Thirty-day cardiac event monitors ( 30-DEM ) may increase the rate of AF detection compared with st and ard investigations that include a combination of electrocardiography , cardiac telemetry , and short-term Holter monitoring . METHODS Charts were review ed of patients who were admitted to a university stroke center or who were evaluated in the outpatient clinic during a 9-month period to determine whether the cause of stroke was cryptogenic . As a matter of protocol , such patients typically underwent 30-DEM and the results of such monitoring were documented along with the duration of inpatient cardiac monitoring if relevant . RESULTS In all , 218 patients with a diagnosis of ischemic stroke or transient ischemic attack were identified . Of the strokes , 36 ( 16.5 % ) were classified as cryptogenic . Twenty patients with cryptogenic stroke or transient ischemic attack were evaluated with 30-DEM . Four ( 20 % ) were found to have AF , and all 4 patients were treated with warfarin . CONCLUSION The 30-DEM changed the medical treatment of 20 % of patients with otherwise cryptogenic stroke because of the detection of intermittent AF despite no detection of AF on electrocardiography and inpatient telemetry monitoring in the majority of patients . Further prospect i ve studies of extended cardiac event monitors in the setting of cryptogenic stroke are warranted Background and Purpose — For patients having suffered ischemic stroke , the current diagnostic strategies often fail to detect atrial fibrillation as a potential cause of embolic events . The aim of the study was to identify paroxysmal atrial fibrillation in stroke patients . We hypothesized that patients with frequent atrial premature beats ( APBs ) recorded in 24-hour ECG will show more often atrial fibrillation when followed by repeated long-term ECG recordings than patients without or infrequent APBs . Methods — 127 patients with acute ischemic stroke and without known AF were enrolled in a prospect i ve study to detect paroxysmal AF . Patients were stratified according to the number of APBs recorded in a 24-hour ECG ( ≥70 APBs versus < 70 APBs ) . Subsequently , they all underwent serial 7-day event-recorder monitoring at 0 , 3 , and 6 months . Results — Serial extended ECG monitoring  identified AF in 26 % of patients with frequent APBs but only in 6.5 % when APBs were infrequent ( P=0.0021 ) . A multivariate analysis showed that the presence of frequent APBs in the initial 24-hour ECG was the only independent predictor of paroxysmal AF during follow-up ( odds ratio 6.6 , 95 % confidence intervals 1.6 to 28.2 , P=0.01 ) . Conclusions — In patients with acute ischemic stroke , frequent APBs ( ≥70/24 hours ) are a marker for individuals who are at greater risk to develop or have paroxysmal AF . For such patients , we propose a diagnostic workup with repeated prolonged ECG monitoring to diagnose paroxysmal AF Background and Purpose — Adequate diagnosis of atrial fibrillation ( AF ) , including paroxysmal AF , is an important part of stroke workup . Prolonged ECG monitoring may improve the detection of paroxysmal , previously undiagnosed AF ( unknown AF ) . Therefore , we evaluated systematic 72-hour Holter ECG monitoring to detect unknown AF for the workup of patients with stroke . Methods — Unselected survivors of a stroke or transient ischemic attack ( TIA ) without known AF were enrolled in a prospect i ve , multicenter cohort study of 72-hour Holter ECG monitoring in 9 German secondary and tertiary stroke centers between May 2010 and January 2011 . In addition to st and ardized workup of stroke pathogenesis according to the German Stroke Unit protocol , all patients underwent 72-hour Holter ECG monitoring directly after admission . All ECGs were central ly analyzed by 2 independent observers . We determined the proportion of unknown AF and compared the detection rates of 72- and 24-hour monitoring . Results — A total of 1135 patients were enrolled ( mean age , 67 years [ SD , 13.1 years ] , 45 % women , 29 % TIA ) .  Unknown AF was detected in 49 out of 1135 patients ( 4.3 % , [ 95 % confidence interval , 3.4–5.2 % ] ) by 72-hour ECG monitoring .  Unknown AF was diagnosed in 29 patients ( 2.6 % ) within the first 24 hours of ECG monitoring , and in 20 more patients only by 72 hours of ECG monitoring . The number needed to screen by 72-hour ECG was 55 patients ( 95 % confidence interval [ 35–123 ] ) for each additional AF diagnosis . Patients with unknown AF were significantly older and had more often a history of previous stroke . Patients with unknown AF were equally distributed within categories of pathogenesis according to Trial of Org 10172 in Acute Stroke Treatment ( TOAST ) classification . Conclusions — In unselected survivors of stroke or TIA , 72-hour ECG monitoring is feasible and improves the detection rate of silent paroxysmal AF Abstract Background and purpose Prolonged Holter monitoring of patients with cerebral ischemia increases the detection rate of paroxysmal atrial fibrillation ( PAF ) ; this leads to improved antithrombotic regimens aim ed at preventing recurrent ischemic strokes . The aim of this study was to compare a 7-day-Holter monitoring ( 7-d-Holter ) alone or in combination with prior selection via transthoracic echocardiography ( TTE ) to a st and ard 24-h-Holter using a cost-utility analysis . Methods Lifetime cost , quality -adjusted life years ( QALY ) , and incremental cost-effectiveness ratios ( ICER ) were estimated for a cohort of patients with acute cerebral ischemia and no contraindication to oral anticoagulation . A Markov model was developed to simulate the long-term course and progression of cerebral ischemia considering the different diagnostic algorithms ( 24-h-Holter , 7-d-Holter , 7-d-Holter after pre selection by TTE ) . Clinical data for these algorithms were derived from the prospect i ve observational Find-AF study ( IS RCT N 46104198 ) . Results Predicted lifelong discounted costs were 33,837 € for patients diagnosed by the 7-d-Holter and 33,852 € by the st and ard 24-h-Holter . Cumulated QALYs were 3.868 for the 7-d-Holter compared to 3.844 for the 24-h-Holter . The 7-d-Holter dominated the 24-h-Holter in the base-case scenario and remained cost-effective in extensive sensitivity analysis of key input parameter with a maximum of 8,354 € /QALY gained . Pre selecting patients for the 7-d-Holter had no positive effect on the cost-effectiveness . Conclusions A 7-d-Holter to detect PAF in patients with cerebral ischemia  is cost-effective . It increases the detection which leads to improved antithrombotic regimens ; therefore , it avoids recurrent strokes , saves future costs , and decreases quality of life impairment . Pre selecting patients by TTE does not improve cost-effectiveness Background and Purpose Diagnosis of paroxysmal atrial fibrillation is difficult but highly relevant in patients presenting with cerebral ischemia yet free from atrial fibrillation on admission . Early initiation and prolongation of continuous Holter monitoring may improve diagnostic yield compared with the st and ard of care including a 24-hour Holter recording . Methods — In the observational Find-AF trial ( IS RCT N 46104198 ) , consecutive patients presenting with symptoms of cerebral ischemia were included . Patients free from atrial fibrillation at presentation received  7-day Holter monitoring .  Results — Two hundred eighty-one patients were prospect ively included . Forty-four ( 15.7 % ) had atrial fibrillation documented by routine electrocardiogram on admission . All remaining patients received Holter monitors at a median of 5.5 hours after presentation . In those 224 patients who received Holter monitors but had no previously known paroxysmal atrial fibrillation , the detection rate with early and prolonged ( 7 days ) Holter monitoring  ( 12.5 % ) was significantly higher than for any 24-hour ( mean of 7 intervals : 4.8 % , P=0.015 ) or any 48-hour monitoring interval ( mean of 6 intervals : 6.4 % , P=0.023 ) . Of those 28 patients with new atrial fibrillation on Holter monitoring , 15 ( 6.7 % ) had been discharged without therapeutic anticoagulation after routine clinical care ( ie , with data from 24-hour Holter monitoring only ) . Detection rates were 43.8 % or 6.3 % for short supraventricular runs of ≥10 beats or prolonged episodes ( < 5 hours ) of atrial fibrillation , respectively . Diagnostic yield appeared to be only slightly and not significantly increased during the first 3 days after the index event . Conclusions — Prolongation of Holter monitoring in patients with symptoms of cerebral ischemic events increases the rate of detection of parox 
    Output:
    
agent
Longer duration of electrocardiographic monitoring after cryptogenic stroke is associated with a greater detection of AF .
***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background and Purpose — Cardioembolism in paroxysmal atrial fibrillation ( pxAF ) is a frequent cause of ischemic stroke . Sensitive detection of pxAF after stroke is crucial for adequate secondary stroke prevention ; the optimal diagnostic modality to detect pxAF on stroke units is unknown . We compared 24-hour Holter electrocardiography ( ECG ) with continuous stroke unit ECG monitoring ( CEM ) for pxAF detection . Methods — Patients with acute ischemic stroke or transient ischemic attack were prospect ively enrolled . After a 12-channel ECG on admission , all patients received 24-hour Holter ECG and CEM . Additionally , ECG monitoring data underwent automated analysis using dedicated software to identify pxAF . Patients with a history of atrial fibrillation or with atrial fibrillation on the admission ECG were excluded . Results — Four hundred ninety-six patients ( median age , 69 years ; 61.5 % male ) fulfilled all inclusion criteria ( ischemic stroke : 80.4 % ; transient ischemic attack : 19.6 % ) . Median stroke unit stay lasted 88.8 hours ( interquartile range , 65.0–122.0 ) .  ECG data  for automated CEM analysis were available for a median time of 64.0 hours ( 43.0–89.8 ) . Paroxysmal AF was documented in 41 of 496 patients ( 8.3 % ) . Of these , Holter detected pxAF in 34.1 % ; CEM in 65.9 % ; and automated CEM in 92.7 % . CEM and automated CEM detected significantly more patients with pxAF than Holter ( P<0.001 ) , and automated CEM detected more patients than CEM ( P<0.001 ) . Conclusions — Automated analysis of CEM improves pxAF detection in patients with stroke on stroke units compared with 24-hour Holter ECG . The comparative usefulness of prolonged or repetitive Holter ECG recordings requires further evaluation Aims Uncertainty exists over the importance of device-detected short- duration atrial arrhythmias . Continuous atrial diagnostics , through home monitoring ( HM ) technology ( BIOTRONIK , Berlin , Germany ) , provides a unique opportunity to assess frequency and quantity of atrial fibrillation ( AF ) episodes defined as atrial high-rate events ( AHRE ) . Methods and results Prospect i ve data from 560 heart failure ( HF ) patients ( age 67 ± 10 years , median ejection fraction 27 % ) patients with a cardiac resynchronization therapy ( CRT ) device capable of HM from two multi-centre studies were analysed . Atrial high-rate events burden was defined as the duration of mode switch in a 24-h period with atrial rates of > 180 beats for at least 1 % or total of 14 min per day . The primary endpoint was incidence of a thromboembolic ( TE ) event . Secondary endpoints were cardiovascular death , hospitalization because of AF , or worsening HF . Over a median 370-day follow-up AHRE occurred in 40 % of patients with 11 ( 2 % ) patients developing TE complications and mortality rate of 4.3 % ( 24 deaths , 16 with cardiovascular aetiology ) . Compared with patients without detected AHRE , patients with detected AHRE>3.8 h over a day were nine times more likely to develop TE complications ( P= 0.006 ) . The majority of patients ( 73 % ) did not show a temporal association with the detected atrial episode and their adverse event , with a mean interval of 46.7 ± 71.9 days ( range 0–194 ) before the TE complication . Conclusion In a high-risk cohort of HF patients , device-detected atrial arrhythmias are associated with an increased incidence of TE events . A cut-off point of 3.8 h over 24 h was associated with significant increase in the event rate . Routine assessment of AHRE should be considered with other data when assessing stroke risk and considering anti-coagulation initiation and should also prompt the optimization of cardioprotective HF therapy in CRT patients INTRODUCTION Despite extensive inpatient workup including telemetry monitoring , a significant proportion of stroke is classified as cryptogenic at hospital discharge . It is possible that a significant proportion of cryptogenic stroke is a result of intermittent atrial fibrillation ( AF ) . Thirty-day cardiac event monitors ( 30-DEM ) may increase the rate of AF detection compared with st and ard investigations that include a combination of electrocardiography , cardiac telemetry , and short-term Holter monitoring . METHODS Charts were review ed of patients who were admitted to a university stroke center or who were evaluated in the outpatient clinic during a 9-month period to determine whether the cause of stroke was cryptogenic . As a matter of protocol , such patients typically underwent 30-DEM and the results of such monitoring were documented along with the duration of inpatient cardiac monitoring if relevant . RESULTS In all , 218 patients with a diagnosis of ischemic stroke or transient ischemic attack were identified . Of the strokes , 36 ( 16.5 % ) were classified as cryptogenic . Twenty patients with cryptogenic stroke or transient ischemic attack were evaluated with 30-DEM . Four ( 20 % ) were found to have AF , and all 4 patients were treated with warfarin . CONCLUSION The 30-DEM changed the medical treatment of 20 % of patients with otherwise cryptogenic stroke because of the detection of intermittent AF despite no detection of AF on electrocardiography and inpatient telemetry monitoring in the majority of patients . Further prospect i ve studies of extended cardiac event monitors in the setting of cryptogenic stroke are warranted Background and Purpose — For patients having suffered ischemic stroke , the current diagnostic strategies often fail to detect atrial fibrillation as a potential cause of embolic events . The aim of the study was to identify paroxysmal atrial fibrillation in stroke patients . We hypothesized that patients with frequent atrial premature beats ( APBs ) recorded in 24-hour ECG will show more often atrial fibrillation when followed by repeated long-term ECG recordings than patients without or infrequent APBs . Methods — 127 patients with acute ischemic stroke and without known AF were enrolled in a prospect i ve study to detect paroxysmal AF . Patients were stratified according to the number of APBs recorded in a 24-hour ECG ( ≥70 APBs versus < 70 APBs ) . Subsequently , they all underwent serial 7-day event-recorder monitoring at 0 , 3 , and 6 months . Results — Serial extended ECG monitoring  identified AF in 26 % of patients with frequent APBs but only in 6.5 % when APBs were infrequent ( P=0.0021 ) . A multivariate analysis showed that the presence of frequent APBs in the initial 24-hour ECG was the only independent predictor of paroxysmal AF during follow-up ( odds ratio 6.6 , 95 % confidence intervals 1.6 to 28.2 , P=0.01 ) . Conclusions — In patients with acute ischemic stroke , frequent APBs ( ≥70/24 hours ) are a marker for individuals who are at greater risk to develop or have paroxysmal AF . For such patients , we propose a diagnostic workup with repeated prolonged ECG monitoring to diagnose paroxysmal AF Background and Purpose — Adequate diagnosis of atrial fibrillation ( AF ) , including paroxysmal AF , is an important part of stroke workup . Prolonged ECG monitoring may improve the detection of paroxysmal , previously undiagnosed AF ( unknown AF ) . Therefore , we evaluated systematic 72-hour Holter ECG monitoring to detect unknown AF for the workup of patients with stroke . Methods — Unselected survivors of a stroke or transient ischemic attack ( TIA ) without known AF were enrolled in a prospect i ve , multicenter cohort study of 72-hour Holter ECG monitoring in 9 German secondary and tertiary stroke centers between May 2010 and January 2011 . In addition to st and ardized workup of stroke pathogenesis according to the German Stroke Unit protocol , all patients underwent 72-hour Holter ECG monitoring directly after admission . All ECGs were central ly analyzed by 2 independent observers . We determined the proportion of unknown AF and compared the detection rates of 72- and 24-hour monitoring . Results — A total of 1135 patients were enrolled ( mean age , 67 years [ SD , 13.1 years ] , 45 % women , 29 % TIA ) .  Unknown AF was detected in 49 out of 1135 patients ( 4.3 % , [ 95 % confidence interval , 3.4–5.2 % ] ) by 72-hour ECG monitoring .  Unknown AF was diagnosed in 29 patients ( 2.6 % ) within the first 24 hours of ECG monitoring , and in 20 more patients only by 72 hours of ECG monitoring . The number needed to screen by 72-hour ECG was 55 patients ( 95 % confidence interval [ 35–123 ] ) for each additional AF diagnosis . Patients with unknown AF were significantly older and had more often a history of previous stroke . Patients with unknown AF were equally distributed within categories of pathogenesis according to Trial of Org 10172 in Acute Stroke Treatment ( TOAST ) classification . Conclusions — In unselected survivors of stroke or TIA , 72-hour ECG monitoring is feasible and improves the detection rate of silent paroxysmal AF Abstract Background and purpose Prolonged Holter monitoring of patients with cerebral ischemia increases the detection rate of paroxysmal atrial fibrillation ( PAF ) ; this leads to improved antithrombotic regimens aim ed at preventing recurrent ischemic strokes . The aim of this study was to compare a 7-day-Holter monitoring ( 7-d-Holter ) alone or in combination with prior selection via transthoracic echocardiography ( TTE ) to a st and ard 24-h-Holter using a cost-utility analysis . Methods Lifetime cost , quality -adjusted life years ( QALY ) , and incremental cost-effectiveness ratios ( ICER ) were estimated for a cohort of patients with acute cerebral ischemia and no contraindication to oral anticoagulation . A Markov model was developed to simulate the long-term course and progression of cerebral ischemia considering the different diagnostic algorithms ( 24-h-Holter , 7-d-Holter , 7-d-Holter after pre selection by TTE ) . Clinical data for these algorithms were derived from the prospect i ve observational Find-AF study ( IS RCT N 46104198 ) . Results Predicted lifelong discounted costs were 33,837 € for patients diagnosed by the 7-d-Holter and 33,852 € by the st and ard 24-h-Holter . Cumulated QALYs were 3.868 for the 7-d-Holter compared to 3.844 for the 24-h-Holter . The 7-d-Holter dominated the 24-h-Holter in the base-case scenario and remained cost-effective in extensive sensitivity analysis of key input parameter with a maximum of 8,354 € /QALY gained . Pre selecting patients for the 7-d-Holter had no positive effect on the cost-effectiveness . Conclusions A 7-d-Holter to detect PAF in patients with cerebral ischemia  is cost-effective . It increases the detection which leads to improved antithrombotic regimens ; therefore , it avoids recurrent strokes , saves future costs , and decreases quality of life impairment . Pre selecting patients by TTE does not improve cost-effectiveness Background and Purpose Diagnosis of paroxysmal atrial fibrillation is difficult but highly relevant in patients presenting with cerebral ischemia yet free from atrial fibrillation on admission . Early initiation and prolongation of continuous Holter monitoring may improve diagnostic yield compared with the st and ard of care including a 24-hour Holter recording . Methods — In the observational Find-AF trial ( IS RCT N 46104198 ) , consecutive patients presenting with symptoms of cerebral ischemia were included . Patients free from atrial fibrillation at presentation received  7-day Holter monitoring .  Results — Two hundred eighty-one patients were prospect ively included . Forty-four ( 15.7 % ) had atrial fibrillation documented by routine electrocardiogram on admission . All remaining patients received Holter monitors at a median of 5.5 hours after presentation . In those 224 patients who received Holter monitors but had no previously known paroxysmal atrial fibrillation , the detection rate with early and prolonged ( 7 days ) Holter monitoring  ( 12.5 % ) was significantly higher than for any 24-hour ( mean of 7 intervals : 4.8 % , P=0.015 ) or any 48-hour monitoring interval ( mean of 6 intervals : 6.4 % , P=0.023 ) . Of those 28 patients with new atrial fibrillation on Holter monitoring , 15 ( 6.7 % ) had been discharged without therapeutic anticoagulation after routine clinical care ( ie , with data from 24-hour Holter monitoring only ) . Detection rates were 43.8 % or 6.3 % for short supraventricular runs of ≥10 beats or prolonged episodes ( < 5 hours ) of atrial fibrillation , respectively . Diagnostic yield appeared to be only slightly and not significantly increased during the first 3 days after the index event . Conclusions — Prolongation of Holter monitoring in patients with symptoms of cerebral ischemic events increases the rate of detection of parox 
    Output:
    