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Stuart J. Connolly - One of the best experts on this subject based on the ideXlab platform.
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temporal relationship between subclinical Atrial Fibrillation and embolic events
Circulation, 2014Co-Authors: Michela Brambatti, Carlos A. Morillo, Stuart J. Connolly, Michael R Gold, Alessandro Capucci, Carmine Muto, C P Lau, Isabelle C Van Gelder, Stefan H Hohnloser, Mark A CarlsonAbstract:Background—Among patients with implantable pacemakers and defibrillators, subclinical Atrial Fibrillation (SCAF) is associated with an increased risk of stroke; however, there is limited understanding of their temporal relationship. Methods and Results—The Asymptomatic Atrial Fibrillation and Stroke Evaluation in Pacemaker Patients and the Atrial Fibrillation Reduction Atrial Pacing Trial (ASSERT) enrolled 2580 pacemaker and defibrillator patients aged ≥65 years with a history of hypertension but without a history of Atrial Fibrillation. Pacemakers and implantable cardioverter-defibrillators precisely logged the time and duration of all episodes of SCAF and recorded electrograms that were adjudicated by experts. We examined the temporal relationship between SCAF >6 minutes in duration and stroke or systemic embolism. Of 51 patients who experienced stroke or systemic embolism during follow-up, 26 (51%) had SCAF. In 18 patients (35%), SCAF was detected before stroke or systemic embolism. However, only 4 pat...
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subclinical Atrial Fibrillation and the risk of stroke
The New England Journal of Medicine, 2012Co-Authors: Jeff S Healey, Stuart J. Connolly, Michael R Gold, Alessandro Capucci, Carsten W Israel, Isabelle C Van Gelder, Eric Fain, Sean Yang, Christophe Bailleul, Carlos A. MorilloAbstract:One quarter of strokes are of unknown cause, and subclinical Atrial Fibrillation may be a common etiologic factor. Pacemakers can detect subclinical episodes of rapid Atrial rate, which correlate with electrocardiographically documented Atrial Fibrillation. We evaluated whether subclinical episodes of rapid Atrial rate detected by implanted devices were associated with an increased risk of ischemic stroke in patients who did not have other evidence of Atrial Fibrillation. Methods We enrolled 2580 patients, 65 years of age or older, with hypertension and no history of Atrial Fibrillation, in whom a pacemaker or defibrillator had recently been implanted. We monitored the patients for 3 months to detect subclinical Atrial tachyarrhythmias (episodes of Atrial rate >190 beats per minute for more than 6 minutes) and followed them for a mean of 2.5 years for the primary outcome of ischemic stroke or systemic embolism. Patients with pacemakers were randomly assigned to receive or not to receive continuous Atrial overdrive pacing. Results By 3 months, subclinical Atrial tachyarrhythmias detected by implanted devices had occurred in 261 patients (10.1%). Subclinical Atrial tachyarrhythmias were associated with an increased risk of clinical Atrial Fibrillation (hazard ratio, 5.56; 95% confidence interval [CI], 3.78 to 8.17; P<0.001) and of ischemic stroke or systemic embolism (hazard ratio, 2.49; 95% CI, 1.28 to 4.85; P = 0.007). Of 51 patients who had a primary outcome event, 11 had had subclinical Atrial tachyarrhythmias detected by 3 months, and none had had clinical Atrial Fibrillation by 3 months. The population attributable risk of stroke or systemic embolism associated with subclinical Atrial tachyarrhythmias was 13%. Subclinical Atrial tachyarrhythmias remained predictive of the primary outcome after adjustment for predictors of stroke (hazard ratio, 2.50; 95% CI, 1.28 to 4.89; P = 0.008). Continuous Atrial overdrive pacing did not prevent Atrial Fibrillation. Conclusions Subclinical Atrial tachyarrhythmias, without clinical Atrial Fibrillation, occurred frequently in patients with pacemakers and were associated with a significantly increased risk of ischemic stroke or systemic embolism. (Funded by St. Jude Medical; ASSERT ClinicalTrials.gov number, NCT00256152.)
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dronedarone in high risk permanent Atrial Fibrillation
The New England Journal of Medicine, 2011Co-Authors: Stuart J. Connolly, Jonathan L. Halperin, Campbell D. Joyner, Marco Alings, John Amerena, Dan Atar, Alvaro Avezum, Per Blomström, John A Camm, Martin BorggrefeAbstract:A b s t r ac t Background Dronedarone restores sinus rhythm and reduces hospitalization or death in intermittent Atrial Fibrillation. It also lowers heart rate and blood pressure and has antiadrenergic and potential ventricular anti-arrhythmic effects. We hypothesized that dronedarone would reduce major vascular events in high-risk permanent Atrial Fibrillation. Methods
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effect of age on stroke prevention therapy in patients with Atrial Fibrillation the Atrial Fibrillation investigators
Stroke, 2009Co-Authors: Carl Van Walraven, Stuart J. Connolly, Pj Koudstaal, Robert G Hart, Peter C Austin, Jonathan Mant, F Richard D Hobbs, Palle Petersen, Francisco Perezgomez, Andre J KnottnerusAbstract:Background and Purpose - Stroke risk increases with age in patients who have nonvalvular Atrial Fibrillation. It is uncertain whether the efficacy of stroke prevention therapies in Atrial Fibrillation changes as patients age. The objective of this study was to determine the effect of age on the relative efficacy of oral anticoagulants (OAC) and antiplatelet (AP) therapy (including acetylsalicylic acid and triflusal) on ischemic stroke, serious bleeding, and vascular events in patients with Atrial Fibrillation. Methods - This is an analysis of the Atrial Fibrillation Investigators database, which contains patient level-data from randomized trials of stroke prevention in Atrial Fibrillation. We used Cox regression models with age as a continuous variable that controlled for sex, year of randomization, and history of cerebrovascular disease, diabetes, hypertension, and congestive heart failure. Outcomes included ischemic stroke, serious bleeding (intracranial hemorrhage or systemic bleeding requiring hospitalization, transfusion, or surgery), and cardiovascular events (ischemic stroke, myocardial infarction, systemic embolism, or vascular death). Results - The analysis included 8932 patients and 17 685 years of observation from 12 trials. Patient age increased risk of ischemic stroke (adjusted hazard ratio per decade increase 1.45; 95% CI, 1.26 to 1.66), serious bleeding (1.61; 1.47 to 1.77), and cardiovascular events (1.43; 1.33 to 1.53). Compared with placebo, OAC and AP significantly reduced the risk of ischemic stroke (OAC, 0.36; 0.29 to 0.45; AP, 0.81; 0.72 to 0.90) and cardiovascular outcomes (OAC, 0.59; 0.52 to 0.66; AP, 0.81; 0.75 to 0.88), whereas OAC increased risk of serious bleeding (1.56; 1.03 to 2.37). The relative benefit of OAC versus placebo or AP did not vary by patient age for any outcome. Compared with placebo, the relative benefit of AP for preventing ischemic stroke decreased significantly as patients aged (P=0.01). Conclusions - As patients with Atrial Fibrillation age, the relative efficacy of AP to prevent ischemic stroke appears to decrease, whereas it does not change for OAC. Because stroke risk increases with age, the absolute benefit of OAC increases as patients get older. © 2009 American Heart Association, Inc.
Carlos A. Morillo - One of the best experts on this subject based on the ideXlab platform.
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approaches to catheter ablation for persistent Atrial Fibrillation
The New England Journal of Medicine, 2015Co-Authors: Atul Verma, Chen-yang Jiang, Timothy R. Betts, Jian Chen, I. Deisenhofer, Roberto Mantovan, Laurent Macle, Carlos A. Morillo, Wilhelm Haverkamp, Rukshen WeerasooriyaAbstract:BackgroundCatheter ablation is less successful for persistent Atrial Fibrillation than for paroxysmal Atrial Fibrillation. Guidelines suggest that adjuvant substrate modification in addition to pulmonary-vein isolation is required in persistent Atrial Fibrillation. MethodsWe randomly assigned 589 patients with persistent Atrial Fibrillation in a 1:4:4 ratio to ablation with pulmonary-vein isolation alone (67 patients), pulmonary-vein isolation plus ablation of electrograms showing complex fractionated activity (263 patients), or pulmonary-vein isolation plus additional linear ablation across the left Atrial roof and mitral valve isthmus (259 patients). The duration of follow-up was 18 months. The primary end point was freedom from any documented recurrence of Atrial Fibrillation lasting longer than 30 seconds after a single ablation procedure. ResultsProcedure time was significantly shorter for pulmonary-vein isolation alone than for the other two procedures (P<0.001). After 18 months, 59% of patients ass...
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cryptogenic stroke and underlying Atrial Fibrillation
The New England Journal of Medicine, 2014Co-Authors: Tommaso Sanna, Carlos A. Morillo, Hans-christoph Diener, Rod S Passman, Richard A Bernstein, Marilyn M Rymer, Vincent Thijs, Tyson Rogers, Frank Beckers, Kate LindborgAbstract:Background Current guidelines recommend at least 24 hours of electrocardiographic (ECG) monitoring after an ischemic stroke to rule out Atrial Fibrillation. However, the most effective duration and type of monitoring have not been established, and the cause of ischemic stroke remains uncertain despite a complete diagnostic evaluation in 20 to 40% of cases (cryptogenic stroke). Detection of Atrial Fibrillation after cryptogenic stroke has therapeutic implications. Methods We conducted a randomized, controlled study of 441 patients to assess whether long-term monitoring with an insertable cardiac monitor (ICM) is more effective than conventional follow-up (control) for detecting Atrial Fibrillation in patients with cryptogenic stroke. Patients 40 years of age or older with no evidence of Atrial Fibrillation during at least 24 hours of ECG monitoring underwent randomization within 90 days after the index event. The primary end point was the time to first detection of Atrial Fibrillation (lasting >30 seconds) within 6 months. Among the secondary end points was the time to first detection of Atrial Fibrillation within 12 months. Data were analyzed according to the intention-to-treat principle. Results By 6 months, Atrial Fibrillation had been detected in 8.9% of patients in the ICM group (19 patients) versus 1.4% of patients in the control group (3 patients) (hazard ratio, 6.4; 95% confidence interval [CI], 1.9 to 21.7; P<0.001). By 12 months, Atrial fib rillation had been detected in 12.4% of patients in the ICM group (29 patients) versus 2.0% of patients in the control group (4 patients) (hazard ratio, 7.3; 95% CI, 2.6 to 20.8; P<0.001). Conclusions ECG monitoring with an ICM was superior to conventional follow-up for detecting Atrial Fibrillation after cryptogenic stroke. (Funded by Medtronic; CRYSTAL AF ClinicalTrials.gov number, NCT00924638.)
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temporal relationship between subclinical Atrial Fibrillation and embolic events
Circulation, 2014Co-Authors: Michela Brambatti, Carlos A. Morillo, Stuart J. Connolly, Michael R Gold, Alessandro Capucci, Carmine Muto, C P Lau, Isabelle C Van Gelder, Stefan H Hohnloser, Mark A CarlsonAbstract:Background—Among patients with implantable pacemakers and defibrillators, subclinical Atrial Fibrillation (SCAF) is associated with an increased risk of stroke; however, there is limited understanding of their temporal relationship. Methods and Results—The Asymptomatic Atrial Fibrillation and Stroke Evaluation in Pacemaker Patients and the Atrial Fibrillation Reduction Atrial Pacing Trial (ASSERT) enrolled 2580 pacemaker and defibrillator patients aged ≥65 years with a history of hypertension but without a history of Atrial Fibrillation. Pacemakers and implantable cardioverter-defibrillators precisely logged the time and duration of all episodes of SCAF and recorded electrograms that were adjudicated by experts. We examined the temporal relationship between SCAF >6 minutes in duration and stroke or systemic embolism. Of 51 patients who experienced stroke or systemic embolism during follow-up, 26 (51%) had SCAF. In 18 patients (35%), SCAF was detected before stroke or systemic embolism. However, only 4 pat...
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subclinical Atrial Fibrillation and the risk of stroke
The New England Journal of Medicine, 2012Co-Authors: Jeff S Healey, Stuart J. Connolly, Michael R Gold, Alessandro Capucci, Carsten W Israel, Isabelle C Van Gelder, Eric Fain, Sean Yang, Christophe Bailleul, Carlos A. MorilloAbstract:One quarter of strokes are of unknown cause, and subclinical Atrial Fibrillation may be a common etiologic factor. Pacemakers can detect subclinical episodes of rapid Atrial rate, which correlate with electrocardiographically documented Atrial Fibrillation. We evaluated whether subclinical episodes of rapid Atrial rate detected by implanted devices were associated with an increased risk of ischemic stroke in patients who did not have other evidence of Atrial Fibrillation. Methods We enrolled 2580 patients, 65 years of age or older, with hypertension and no history of Atrial Fibrillation, in whom a pacemaker or defibrillator had recently been implanted. We monitored the patients for 3 months to detect subclinical Atrial tachyarrhythmias (episodes of Atrial rate >190 beats per minute for more than 6 minutes) and followed them for a mean of 2.5 years for the primary outcome of ischemic stroke or systemic embolism. Patients with pacemakers were randomly assigned to receive or not to receive continuous Atrial overdrive pacing. Results By 3 months, subclinical Atrial tachyarrhythmias detected by implanted devices had occurred in 261 patients (10.1%). Subclinical Atrial tachyarrhythmias were associated with an increased risk of clinical Atrial Fibrillation (hazard ratio, 5.56; 95% confidence interval [CI], 3.78 to 8.17; P<0.001) and of ischemic stroke or systemic embolism (hazard ratio, 2.49; 95% CI, 1.28 to 4.85; P = 0.007). Of 51 patients who had a primary outcome event, 11 had had subclinical Atrial tachyarrhythmias detected by 3 months, and none had had clinical Atrial Fibrillation by 3 months. The population attributable risk of stroke or systemic embolism associated with subclinical Atrial tachyarrhythmias was 13%. Subclinical Atrial tachyarrhythmias remained predictive of the primary outcome after adjustment for predictors of stroke (hazard ratio, 2.50; 95% CI, 1.28 to 4.89; P = 0.008). Continuous Atrial overdrive pacing did not prevent Atrial Fibrillation. Conclusions Subclinical Atrial tachyarrhythmias, without clinical Atrial Fibrillation, occurred frequently in patients with pacemakers and were associated with a significantly increased risk of ischemic stroke or systemic embolism. (Funded by St. Jude Medical; ASSERT ClinicalTrials.gov number, NCT00256152.)
Albert L Waldo - One of the best experts on this subject based on the ideXlab platform.
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Mapping the conversion of Atrial flutter to Atrial Fibrillation and Atrial Fibrillation to Atrial flutter. Insights into mechanisms.
Circulation Research, 1994Co-Authors: José Ortiz, Nancy J. Johnson, Yoram Rudy, Shinichi Niwano, Albert L WaldoAbstract:It is not generally believed that there is a relation between Atrial flutter, thought to be due to a single reentrant circuit, and Atrial Fibrillation, thought to be due to simultaneously circulating multiple-reentrant wave fronts. However, there are many reasons to suggest that these rhythms are more closely related than previously thought. To test the hypothesis that the length of an area of functional block in the right Atrial free wall is critical to the conversion of Atrial flutter to Atrial Fibrillation and of Atrial Fibrillation to Atrial flutter, we studied spontaneous and ATP-induced conversion of stable Atrial flutter to sustained Atrial Fibrillation and spontaneous conversion of sustained Atrial Fibrillation to stable Atrial flutter. We studied 13 episodes of the conversion of stable Atrial flutter to sustained Atrial Fibrillation and sustained Atrial Fibrillation to stable Atrial flutter in seven dogs with sterile pericarditis. Six episodes were spontaneous and seven were ATP related. All episodes were studied by using a multisite mapping system to record 190 unipolar electrograms (converted in the software to 95 bipolar electrograms) from the right Atrial free wall along with ECG lead II. Atrial flutter induction was attempted by Atrial stimulation (S1S2 or S1S2S3) or by rapid Atrial pacing for > or = 20 beats from selected sites at selected rates. For both the spontaneous and the ATP-related episodes, stable Atrial flutter was defined as any episode of > or = 5 minutes, and sustained Atrial Fibrillation was any episode of > or = 1 minute. During all the episodes of stable Atrial flutter, a line of functional block with a mean length of 24 +/- 4 mm was localized on the right Atrial free wall. When the previously stable line of functional block decreased to a mean of 16 +/- 3 mm (P or = prior length) to create a stable reentrant circuit, which then captured the right Atrial free wall and subsequently both atria.(ABSTRACT TRUNCATED AT 400 WORDS)
Andre J Knottnerus - One of the best experts on this subject based on the ideXlab platform.
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effect of age on stroke prevention therapy in patients with Atrial Fibrillation the Atrial Fibrillation investigators
Stroke, 2009Co-Authors: Carl Van Walraven, Stuart J. Connolly, Pj Koudstaal, Robert G Hart, Peter C Austin, Jonathan Mant, F Richard D Hobbs, Palle Petersen, Francisco Perezgomez, Andre J KnottnerusAbstract:Background and Purpose - Stroke risk increases with age in patients who have nonvalvular Atrial Fibrillation. It is uncertain whether the efficacy of stroke prevention therapies in Atrial Fibrillation changes as patients age. The objective of this study was to determine the effect of age on the relative efficacy of oral anticoagulants (OAC) and antiplatelet (AP) therapy (including acetylsalicylic acid and triflusal) on ischemic stroke, serious bleeding, and vascular events in patients with Atrial Fibrillation. Methods - This is an analysis of the Atrial Fibrillation Investigators database, which contains patient level-data from randomized trials of stroke prevention in Atrial Fibrillation. We used Cox regression models with age as a continuous variable that controlled for sex, year of randomization, and history of cerebrovascular disease, diabetes, hypertension, and congestive heart failure. Outcomes included ischemic stroke, serious bleeding (intracranial hemorrhage or systemic bleeding requiring hospitalization, transfusion, or surgery), and cardiovascular events (ischemic stroke, myocardial infarction, systemic embolism, or vascular death). Results - The analysis included 8932 patients and 17 685 years of observation from 12 trials. Patient age increased risk of ischemic stroke (adjusted hazard ratio per decade increase 1.45; 95% CI, 1.26 to 1.66), serious bleeding (1.61; 1.47 to 1.77), and cardiovascular events (1.43; 1.33 to 1.53). Compared with placebo, OAC and AP significantly reduced the risk of ischemic stroke (OAC, 0.36; 0.29 to 0.45; AP, 0.81; 0.72 to 0.90) and cardiovascular outcomes (OAC, 0.59; 0.52 to 0.66; AP, 0.81; 0.75 to 0.88), whereas OAC increased risk of serious bleeding (1.56; 1.03 to 2.37). The relative benefit of OAC versus placebo or AP did not vary by patient age for any outcome. Compared with placebo, the relative benefit of AP for preventing ischemic stroke decreased significantly as patients aged (P=0.01). Conclusions - As patients with Atrial Fibrillation age, the relative efficacy of AP to prevent ischemic stroke appears to decrease, whereas it does not change for OAC. Because stroke risk increases with age, the absolute benefit of OAC increases as patients get older. © 2009 American Heart Association, Inc.
Nassir F Marrouche - One of the best experts on this subject based on the ideXlab platform.
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catheter ablation for Atrial Fibrillation with heart failure
The New England Journal of Medicine, 2018Co-Authors: Nassir F Marrouche, Johannes Brachmann, Prashanthan Sanders, Dietrich Andresen, Jurgen Siebels, Lucas V A Boersma, Luc Jordaens, Bela Merkely, Evgeny Pokushalov, Jochen ProffAbstract:Abstract Background Mortality and morbidity are higher among patients with Atrial Fibrillation and heart failure than among those with heart failure alone. Catheter ablation for Atrial Fibrillation has been proposed as a means of improving outcomes among patients with heart failure who are otherwise receiving appropriate treatment. Methods We randomly assigned patients with symptomatic paroxysmal or persistent Atrial Fibrillation who did not have a response to antiarrhythmic drugs, had unacceptable side effects, or were unwilling to take these drugs to undergo either catheter ablation (179 patients) or medical therapy (rate or rhythm control) (184 patients) for Atrial Fibrillation in addition to guidelines-based therapy for heart failure. All the patients had New York Heart Association class II, III, or IV heart failure, a left ventricular ejection fraction of 35% or less, and an implanted defibrillator. The primary end point was a composite of death from any cause or hospitalization for worsening heart f...
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incidence of Atrial Fibrillation post cavotricuspid isthmus ablation in patients with typical Atrial flutter left Atrial size as an independent predictor of Atrial Fibrillation recurrence
Journal of Cardiovascular Electrophysiology, 2007Co-Authors: Keith Ellis, Nassir F Marrouche, Patrick M Mccarthy, Oussama Wazni, David O Martin, Marc Gillinov, Eduardo B Saad, Mandeep Bhargava, Robert A Schweikert, Walid SalibaAbstract:Introduction: Atrial Fibrillation and Atrial flutter often coexist. The long-term occurrence of Atrial Fibrillation in patients presenting with Atrial flutter alone is unknown. We report the long-term follow-up in patients who underwent cavotricuspid isthmus ablation for treatment of lone Atrial flutter. Methods and Results: Between January 1997 and June 2002, 632 patients underwent cavotricuspid isthmus ablation for the treatment of typical Atrial flutter at the Cleveland Clinic Foundation. Three hundred sixty-three patients were included in this study and followed for a mean duration of 39 ± 11 months. The mean duration of Atrial flutter symptoms was 12 ± 5 months. Mean left-Atrial size and left-ventricular ejection fraction were 4.2 ± 0.8 cm and 47 ± 13%, respectively. After a mean follow-up time of 39 ± 11 months, 13% (48 of 363) of the patients remained in sinus rhythm. Five percent (18 of 363) of patients experienced recurrence of Atrial flutter only. Sixty-eight percent (246 of 363) experienced the onset of Atrial Fibrillation and 14% (51 of 363) experienced recurrence of Atrial flutter and the new onset of Atrial Fibrillation. Overall, 82% (297 of 363) of the patients experienced new onset of drug refractory Atrial Fibrillation. Left-Atrial size was a predictor of Atrial Fibrillation recurrence post-Atrial flutter ablation. Conclusion: At long-term follow-up, approximately 82% of patients post-cavotricuspid isthmus ablation for Atrial flutter developed drug refractory Atrial Fibrillation. This finding suggests that elimination of Atrial flutter might delay, but does not prevent, Atrial Fibrillation. Evidence suggests both arrhythmias may share common triggers and such patients may derive a better long-term benefit from anatomical ablative treatment of Atrial Fibrillation as well.