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AF Patients (af + patient)
Selected AbstractsMitral Regurgitation Associated with Mitral Annular Dilation in Patients with Lone Atrial Fibrillation: An Echocardiographic StudyECHOCARDIOGRAPHY, Issue 8 2009Takashi Kihara M.D. Background: Whether and how lone atrial fibrillation (AF) is associated with functional mitral regurgitation (MR) remain unclear. Method: We studied 12 lone AF patients without left ventricular (LV) dysfunction and/or dilatation, who underwent mitral valve annuloplasty for functional mitral regurgitation (MR). Ten lone AF patients without MR served as controls. Results: Lone AF Patients with MR had a greater mitral valve annular area and left atrial area than those without MR. There were no differences in LV volumes or LV ejection fraction. Conclusions: Therefore, we concluded that left atrial dilation and corresponding mitral annular dilation may cause MR in lone AF patients without LV dysfunction and/or dilatation. [source] The Impact of Age on the Electroanatomical Characteristics and Outcome of Catheter Ablation in Patients with Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2010TA-CHUAN TUAN M.D. Age and Atrial Fibrillation.,,Background: Previous studies have indicated that atrial fibrillation (AF) in patients over the age of 60 at diagnosis is a risk factor for a substantial increase in cardiovascular events. However, information about the impact of age on the atrial substrate and clinical outcome after catheter ablation of AF is limited. Methods: This study included 350 patients (53 ± 12 years, 254 males) who underwent circumferential pulmonary vein isolation (CPVI) of AF, guided by a NavX mapping system. The subjects were divided into three groups according to their age, as follows: Group I: age ,50 (n = 141), Group II: age = 51,64 (n = 149) and Group III: age ,65 years old (n = 60). The mean voltage and total activation time of the individual atria were obtained by using a NavX mapping system before ablation. Several parameters, including the gender, AF duration, and left atrial (LA) diameter were analyzed. Results: The younger age group had a significantly smaller LA diameter (Group I vs Group II vs Group III, 36.89 ± 7.11 vs 39.16 ± 5.65 vs 40.77 ± 4.95 mm, P = 0.002) and higher LA bipolar voltage (2.09 ± 0.83 vs 1.73 ± 0.73 vs 1.86 ± 0.67 mV, respectively, P = 0.024), compared with the older AF patients. The LA bipolar voltage exhibited a significant reduction when the patients became older, however, that did not occur in the right atrium. The incidence of an AF recurrence was higher in the older age group than in the younger age groups. A subgroup of patients with lone AF was analyzed and age was found to be an independent predictor of the AF recurrence after receiving the first CPVI in the multivariable model (P < 0.05). Conclusions: Age has a significant impact on the LA substrate properties and outcome of the catheter ablation of AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 966-972, September 2010) [source] ATP-Induced Dormant Pulmonary Veins Originating from the Carina Region After Circumferential Pulmonary Vein Isolation of Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2010KOJI KUMAGAI M.D., Ph.D. Dormant Pulmonary Veins from the Carina Region.,Introduction: Elimination of transient pulmonary vein recurrences (dormant PVs) induced by an ATP injection and ablation at the PV carina region is an effective strategy for atrial fibrillation (AF) ablation. The relationship between dormant PVs and the PV carina region has not been evaluated. Methods: A total of 212 consecutive symptomatic AF patients underwent circumferential PV electrical isolation (CPVEI) with a double lasso technique. They were divided into 2 groups in a retrospective review; Group 1: those given an ATP injection during an intravenous isoproterenol infusion after the CPVEI (n = 106), and Group 2: those in which it was not given after the CPVEI (n = 106). Radiofrequency energy was applied at the earliest dormant PV activation site identified using a Lasso catheter on the CPVEI line and then PV carina region if it was ineffective. Results: After a successful PVEI, 54 patients (51%) in Group 1 had PV reconnections during an ATP injection. Acute PVEI sites were observed on the carina region within the CPVEI line in the right PVs (16%) and left PVs (10%). Dormant PVs were reisolated at the carina region in the right PVs (23%) and left PVs (26%). The distribution of the dormant PV sites, except for the RIPV, significantly differed from that of the acute PVEI sites (P < 0.05). Further, AF recurred significantly in the Group 2 patients as compared to those in Group 1 during 16 ± 6.1 months of follow-up (P < 0.05). Conclusion: PV carina region origins may partly be responsible for an acute PVEI and potential recurrences. (J Cardiovasc Electrophysiol, Vol. 21, pp. 494-500, May 2010) [source] Biatrial Substrate Properties in Patients with Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2007SHIH-LIN CHANG M.D. Introduction: The atrial substrate plays an important role in the maintenance of atrial fibrillation (AF). Further investigation of the biatrial substrate may be helpful for understanding the mechanism of AF. The aim of this study was to investigate the properties of right and left atrial (RA and LA) substrate in AF patients and their impact on the catheter ablation. Methods: Biatrial electroanatomic mapping using a three-dimensional mapping system (NavX) was performed in 117 consecutive patients with paroxysmal (n = 99) and persistent (n = 18) AF. The biatrial voltage and total activation time (TAT) were obtained during sinus rhythm. Results: The LA had a lower voltage (1.6 ± 0.5 vs 2.0 ± 0.6 mV, P < 0.001) than the RA. The TAT correlated with the voltage (r =,0.65, P< 0.001). The patients with persistent AF had a lower atrial voltage, higher coefficient of variance for the LA voltage, longer LA TAT, and more extensive scar than those with paroxysmal. The patients with recurrent AF after catheter ablation had a lower LA voltage and higher incidence of LA scarring than those without recurrence. A scar located in the low anteroseptal or low posterior wall of LA was related to recurrence of AF. LA scarring was the independent predictor of AF recurrence after catheter ablation. Conclusion: The LA voltage was lower than the RA, and the atrial voltage correlated with the TAT. Electroanatomical remodeling of the atria could be crucial to the maintenance of AF. The LA substrate properties may play an important role in the recurrence of AF after catheter ablation of AF. [source] Spontaneous Pulmonary Vein Firing in Man: Relationship to Tachycardia-Pause Early Afterdepolarizations and Triggered Arrhythmia in Canine Pulmonary Veins In VitroJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2007EUGENE PATTERSON Ph.D. Introduction: Rapid firing originating within pulmonary veins (PVs) initiates atrial fibrillation (AF). The following studies were performed to evaluate spontaneous PV firing in patients with AF to distinguish focal versus reentrant mechanisms. Methods: Intracardiac recordings were obtained in 18 patients demonstrating paroxysmal AF. Microelectrode (ME) recordings were obtained from superfused canine PV sleeves (N = 48). Results: Spontaneous PV firing (566 ± 16 bpm; 127 ± 6 ms cycle length) giving rise to AF (52 episodes) was observed. Tachycardia-pause initiation was present in 132 of 200 episodes of rapid PV firing and 34 of 52 AF episodes. The pause cycle length preceding PV firing was 1,039 ± 86 ms following tachycardia (420 ± 40 ms cycle length). The remaining episodes were initiated following a 702 ± 32 ms pause during sinus rhythm (588 ± 63 ms). Spontaneous firing recorded with a multipolar mapping catheter did not detect electrical activity bridging the diastolic interval between the initial ectopic and preceding post-pause sinus beat. Tachycardia-pause initiated PV firing (138 ± 7 ms coupling interval) in patients correlated with tachycardia-pause enhanced isometric force, early afterdepolarization (EAD) amplitude, and triggered firing within canine PVs. Rapid firing (1,172 ± 134 bpm; 51 ± 8 ms cycle length) following an abbreviated coupling interval (69 ± 12 ms) was initiated in 13 of 18 canine PVs following tachycardia-pause pacing during norepinephrine + acetylcholine superfusion. Stimulation selectively activating local autonomic nerve terminals facilitated tachycardia-pause triggered firing in canine PVs (5 of 15 vs 0 of 15; P < 0.05). Conclusions: The studies demonstrate (1) tachycardia-pause initiation of rapid, short-coupled PV firing in AF patients and (2) tachycardia-pause facilitation of isometric force, EAD formation, and autonomic-dependent triggered firing within canine PVs, suggestive of a common arrhythmia mechanism. [source] Morphologic Characteristics of the Left Atrial Appendage, Roof, and Septum: Implications for the Ablation of Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2006WANWARANG WONGCHAROEN M.D. Introduction: The left atrium (LA) ablation in different regions, including LA appendage (LAA), LA roof, and LA septum, has recently been proposed to improve the success rate of treating patients with atrial fibrillation (AF). The purpose of this study was to investigate the anatomy of LAA, LA roof, and LA septum, using computed tomography (CT). Methods and Results: Multidetector CT scan was used to depict the LA in 47 patients with drug-refractory paroxysmal AF (39 males, age = 50 ± 12 years) and 49 control subjects (34 males, age = 54 ± 11 years). The area of LAA orifice, neck, and the length of roof line were greater in AF group than in control subjects. Three types of LAA locations and two types of LAA ridges were observed. Higher incidence of inferior LAA was noted in AF patients. The different morphologies of LA roof were described. Roof pouches were revealed in 15% of AF and 14% of controls. Moreover, we found septal ridge in 32% of AF and 23% of controls. Conclusions: Considerable variations of LAA and LA roof morphologies were demonstrated. Peculiar structures, including roof pouches and septal ridges, were delineated by CT imaging. These findings were important for determining the strategy of AF ablation and avoiding the procedure-related complications. [source] Preoperative Electrocardiographic Risk Assessment of Atrial Fibrillation After Coronary Artery Bypass GraftingJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2004Ph.D., YI GANG M.D. Introduction: This study evaluated the role of surface ECG in assessment of risk of new-onset atrial fibrillation (AF) after coronary artery bypass grafting surgery (CABG). Methods and Results: One hundred fifty-one patients (126 men and 25 women; age 65 ± 10 years) without a history of AF undergoing primary elective and isolated CABG were studied. Standard 12-lead ECGs and P wave signal-averaged ECG (PSAE) were recorded 24 hours before CABG using a MAC VU ECG recorder. In addition to routine ECG measurements, two P wave (P wave complexity ratio [pCR]; P wave morphology dispersion [PMD]) and six T wave morphology descriptors (total cosine R to T [TCRT]; T wave morphology dispersion of ascending and descending part of the T wave [aTMD and dTMD], and others), and three PSAE indices (filtered P wave duration [PD]; root mean square voltage of terminal 20 msec of averaged P wave [RMS20]; and integral of P wave [Pi]) were investigated. During a mean hospital stay of 7.3 ± 6.2 days after CABG, 40 (26%) patients developed AF (AF group) and 111 remained AF-free (no AF group). AF patients were older (69 ± 9 years vs 64 ± 10 years, P = 0.005). PD (135 ± 9 msec vs 133 ± 12 msec, P = NS) and RMS20 (4.5 ± 1.7 ,V vs 4.0 ± 1.6 ,V, P = NS) in AF were similar to that in no AF, whereas Pi was significantly increased in AF (757 ± 230 ,Vmsec vs 659 ± 206 ,Vmsec, P = 0.007). Both pCR (32 ± 11 vs 27 ± 10) and PMD (31.5 ± 14.0 vs 26.4 ± 12.3) were significantly greater in AF (P = 0.012 and 0.048, respectively). TCRT (0.028 ± 0.596 vs 0.310 ± 0.542, P = 0.009) and dTMD (0.63 ± 0.03 vs 0.64 ± 0.02, P = 0.004) were significantly reduced in AF compared with no AF. Measurements of aTMD and three other T wave descriptors were similar in AF and no AF. Significant variables by univariate analysis, including advanced age (P = 0.014), impaired left ventricular function (P = 0.02), greater Pi (P = 0.012), and lower TCRT (P = 0.007) or dTMD, were entered into multiple logistic regression models. Increased Pi (P = 0.038), reduced TCRT (P = 0.040), and lower dTMD (P = 0.014) predicted AF after CABG independently. In patients <70 years, a linear combination of increased pCR and lower TCRT separated AF and no AF with a sensitivity of 74% and specificity of 62% (P = 0.005). Conclusion: ECG assessment identifies patients vulnerable to AF after CABG. Combination of ECG parameters assessed preoperatively may play an important role in predicting new-onset AF after CABG. [source] Clustering of RR Intervals Predicts Effective Electrical Cardioversion for Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2004MAARTEN P. VAN DEN BERG M.D. Introduction: Atrial fibrillation (AF) is characterized by an irregularly irregular ("random") heart beat. However, controversy exists whether the ventricular rhythm in AF is truly random. We investigated randomness by constructing three-dimensional RR interval plots (3D plots), allowing identification of "clustering" of RR intervals. It was hypothesized that electrical cardioversion (ECV) would be more effective in AF patients with clustering, because clustering might reflect a higher degree of organization of atrial fibrillatory activity. Methods and Results: The study group consisted of 66 patients (44 men and 22 women; mean age 68 ± 11 years,) who were referred for ECV because of persistent AF. Twenty-four-hour Holter recordings were used to construct 3D plots by plotting each RR interval (x axis) against the previous RR interval (y axis) and the number of occurrences of each of these x,y combinations (z axis). A clustering index was calculated as the percentage of beats within the peaks in the 3D plot. Based on the 3D plots, clustering of RR intervals was present in 31 (47%) of the 66 patients. ECV was effective in restoring sinus rhythm in 29 (94%) of these 31 patients, whereas sinus rhythm was restored in only 25 (71%) of the remaining 35 patients without clustering (P = 0.020). The clustering index ranged from <2% in the 12 patients with failed ECV to >8% in the 32 patients with sinus rhythm at the end of the study (4 weeks after the ECV); the clustering index in the 22 patients with a relapse of AF after effective ECV was intermediate (P = 0.034 and P = 0.042, respectively). Conclusion: This study indicates that ECV is more effective in restoring sinus rhythm in AF patients with clustering compared to patients in whom no clustering is apparent on 3D plots. In addition, the degree of clustering appears to be predictive of the overall outcome of ECV; the higher the degree of clustering, the higher the likelihood of sinus rhythm at follow-up. [source] Conduction Characteristics at the Crista Terminalis During Onset of Pulmonary Vein Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2004SIMON P. FYNN M.D. Introduction: Focal atrial fibrillation (AF) may initiate with an irregular rapid burst of atrial ectopic (AE) activity from a pulmonary vein (PV) focus, but how AF is maintained it is not known. The crista terminalis (CT) is an important line of block in atrial flutter (AFL), but its role in AF has not been determined. The aim of this study was to examine the conduction properties of the CT during onset of AF. Methods and Results: In 10 patients (mean age 38 ± 8 years), we analyzed conduction across the CT during onset of focal AF from an arrhythmogenic PV and during pacing from the same PV at cycle lengths of 700 and 300 ms. A 20-pole catheter was positioned on the CT using intracardiac echocardiography. In 10 control patients with no history of AF, we analyzed conduction across the CT during pacing from the distal coronary sinus at 700 and 300 ms. In all 10 AF patients, AF was initiated with 1 to 9 AE beats (median 5) from a PV. During sinus rhythm, there were no split components (SC) recorded on the CT. During PV AE activity, discrete SC were recorded on the CT in all patients over 6.3 ± 0.9 bipoles (3.7 ± 0.3 cm). Maximal splitting of SC was 66 ± 31 ms (37,139). There was an inverse relationship between AE coupling intervals and the degree of splitting between SC in all patients. Degeneration to AF was preceded by progressive decrement across the CT. SC were recorded during PV pacing at 700 and 300 ms (maximal distance between SC of 24 ± 3 ms and 43 ± 5 ms, respectively, P < 0.001). Maximum SC at CT in controls was 13 ± 8 ms at 700 ms (P = 0.06 vs AF patients) and 16 ± 9 ms at 300 ms (P < 0.01 vs AF patients). Conclusion: (1) These observations provide evidence of anisotropic, decremental conduction across the CT during onset of focal AF and during pacing from the same PV. A line of functional conduction block develops along this anatomic structure (CT). Whether this line of block acts as an initiator of AF or simply contributes passively to nonuniform fibrillatory conduction is unknown. (2) In some patients with focal AF, development of conduction block along the CT may provide a substrate for typical AFL. [source] Atrial Size Reduction as a Predictor of the Success of Radiofrequency Maze Procedure for Chronic Atrial Fibrillation in Patients Undergoing Concomitant Valvular SurgeryJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2001MIEN-CHENG CHEN M.D. Radiofrequency Maze Procedure and Atrial Size.Introduction: Previous studies showed that the surgical maze procedure can restore sinus rhythm and atrial transport function in patients with chronic atrial fibrillation (AF). However, no previous studies discussed the association of atrial size reduction and the success of sinus conversion by the radiofrequency (RF) maze procedure for chronic AF. Methods and Results: A total of 119 chronic AF patients undergoing valvular operations were included in this study. Sixty-one patients received RF and cryoablation to create lesions in both atria to simulate the surgical maze II or III procedure (RF maze II or RF maze III; 13 patients, group 1) or a modified maze pattern (RF maze "IV"; 48 patients, group 2). The other 58 patients who underwent valvular operations alone without the maze procedure served as control (group 3). At 3-month follow-up after operation, sinus rhythm was restored in 73%, 81%, and 11% of patients in groups 1, 2 and 3, respectively. Preoperative left and right atrial sizes were not statistically significant predictors of sinus conversion by the RF maze procedure. However, as a result of postoperative reduction of atrial sizes, postoperative left atrial diameter was significantly smaller in patients who had sinus conversion by the RF maze procedure than in patients who did not regain sinus rhythm (45.0 ± 7.0 mm vs 51.0 ± 8.0 mm; P = 0.03). Postoperative right atrial area of patients who had sinus conversion by the RF maze procedure also was significantly smaller than that of patients who did not regain sinus rhythm (18.1 ± 4.4 cm2 vs 28.5 ± 8.2 cm2; P = 0.008). Conclusion: Atrial size reduction appears to predict the success of sinus conversion with the RF maze procedure used in conjunction with valvular surgery. [source] Increased Levels of Tissue Plasminogen Activator Antigen and Factor VIII Activity in Nonvalvular Atrial Fibrillation: Relation to Predictors of ThromboembolismJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2001TZUNG-DAU WANG M.D. Atrial Fibrillation and Hypercoagulability.Introduction: Given that nonvalvular atrial fibrillation (AF)-associated stroke can be either cardioembolic or atherothrombotic, we investigated the relationships between nonvalvular AF and hemostatic factors reflecting intrinsic thrombogenic and atherogenic potentials (tissue plasminogen activator [t-PA] antigen, plasminogen activator inhibitor-1, and factor VIII activity). We also evaluated the clinical applicability of these hemostatic factors by examining whether AF subjects with established clinical or echocardiographic predictors of thromboembolism had higher levels of these factors. Methods and Results: Of the 3,212 participants of a Chinese population-based study, 53 subjects (1.7%) with AF were identified. Among the hemostatic factors measured, t-PA antigen (median 12.8 vs 8.1 ng/mL; P < 0.01) and factor VIII activity (median 155% vs 133%; P < 0.05) were significantly higher in AF subjects after adjustment for age and sex. In multivariate analysis, features independently associated with t-PA antigen levels were AF, age, sex, body mass index, systolic blood pressure, total cholesterol, triglycerides, and left ventricular systolic dysfunction. Features independently associated with factor VIII activity levels included AF, age, and total cholesterol. Levels of both t-PA antigen and factor VIII activity were primarily elevated in AF subjects with predictors of thromboembolism (age > 75 years, hypertension, diabetes, and left ventricular systolic dysfunction), whereas in AF subjects with no thromboembolic predictors, plasma levels of hemostatic factors examined were similar to those without AF. Conclusion: We demonstrated that nonvalvular AF was independently associated with increased peripheral levels of t-PA antigen and factor VIII activity. Levels of both hemostatic factors were primarily elevated in AF subjects with predictors of thromboembolism. Whether these hemostatic factors are independently predictive of future thromboembolic events in AF patients requires further investigation. [source] Endothelin System in Human Persistent and Paroxysmal Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2001BIANCA J.J.M. BRUNDEL Ph.D. Endothelin System in Atrial Fibrillation. Introduction: Activation of the endothelin system is an important compensatory mechanism that is activated during left ventricular dysfunction. Whether this system plays a role at the atrial level during atrial fibrillation (AF) has not been examined in detail. The purpose of this study was to investigate mRNA and protein expression levels of the endothelin system in AF patients with and without concomitant underlying valve disease. Methods and Results: Right atrial appendages of 36 patients with either paroxysmal or persistent AF were compared with 36 controls in sinus rhythm. The mRNA amounts of pro-endothelin-1 (pro-ET-1), endothelin receptor A (ET-A), and endothelin receptor B (ET-B) were studied by semiquantitative polymerase chain reaction. Protein amounts of the receptors were investigated by slot-blot analysis. mRNA amounts of pro-ET-1 were increased (+ 40%; P = 0.002) only in AF patients with underlying valve disease. ET-A and ET-B receptor protein amounts were significantly reduced in patients with paroxysmal AF (,39% and ,47%, respectively) and persistent AF with underlying valve disease (, 28% and , 30%, respectively) and in persistent AF without valve disease (,20% and ,40%, respectively). ET-A mRNA expression was unaltered in paroxysmal and persistent AF, whereas ET-B mRNA was reduced by 30% in persistent AF with (P < 0.001) or without (P = 0.04) valve disease, but unchanged in paroxysmal AF. Conclusion: Substantial changes in gene expression of the endothelin system were observed in human atria during AF, especially in the presence of underlying valve disease. Alterations in endothelin expression associated with AF could play a role in the pathophysiology of AF and the progression of underlying heart disease. [source] Sinus Pacemaker Function after Cardioversion of Chronic Atrial Fibrillation: Is Sinus Node Remodeling Related with Recurrence?JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2001EMMANUEL G. MANIOS M.D. Sinus Node Remodeling and Atrial Fibrillation. Introduction: The objective of this study was to investigate the temporal changes in sinus node function in postcardioversion chronic atrial fibrillation (AF) patients and their possible relation with the recurrence rates of AF. Methods and Results: In 37 chronic AF patients, internally cardioverted to sinus rhythm, corrected sinus node recovery time (CSNRT), and the pattern of corrected return cycle lengths were assessed 5 to 20 minutes and 24 hours after conversion. The last 20 consecutive patients also were evaluated after autonomic blockade. Twenty subjects with normal atrial structure and no history of AF served as the control group. Patients were followed-up for 1 month for recurrence, and the density of supraventricular ectopic beats per hour was obtained during the first 24 hours after conversion. Fifteen patients (40.5%) relapsed during follow-up. CSNRT values at 600 msec (371 ± 182 msec) and 500 ms (445 ± 338 msec) were significantly higher than those of control subjects (278 ± 157 msec, P = 0.050, and 279 ± 130 msec, P = 0.037, respectively). Significant temporal changes in CSNRT also were observed during the first 24 hours after conversion (600 msec: 308 ± 120 msec, P = 0.034; 500 msec: 340 ± 208 msec, P = 0.017). No significant interaction and temporal effects were observed with regard to corrected return cycle length pattern. Similar data regarding CSNRT and corrected return cycle length pattern were obtained after autonomic blockade. Patients with abnormal CSNRT after cardioversion had higher recurrence rates (50%) than those with normal function (37%; P = NS). Patients who relapsed had a higher density of supraventricular ectopic beats per hour (159 ± 120) compared with those who did not (35 ± 37; P = 0.001). Conclusion: Depressed sinus node function is observed after conversion of chronic AF. Recovery from this abnormality and its independence from autonomic function suggest that AF remodels the sinus node. Our data do not support a causative role of sinus node function in AF recurrence, but they do indicate such a role for the density of atrial ectopic beats. [source] Effects of low-dose warfarin and aspirin versus no treatment on stroke in a medium-risk patient population with atrial fibrillationJOURNAL OF INTERNAL MEDICINE, Issue 1 2003N. Edvardsson Abstract. Edvardsson N, Juul-Möller S, Ömblus R, Pehrsson K (Sahlgrenska University Hospital, Malmö University Hospital, Bristol-Myers Squibb Bromma; and Karolinska University Hospital; Stockholm, Sweden). Effects of low-dose warfarin and aspirin versus no treatment on stroke in a medium-risk patient population with atrial fibrillation. J Intern Med 2003; 254: 95,101. Objectives. To assess the optimal stroke prevention treatment for patients with atrial fibrillation (AF) and a low,medium risk (,4%) of stroke. Design. A total of 668 patients with persistent or permanent AF, without an indication for full dose and with adequate rate control on sotalol, were randomized to warfarin 1.25 mg + aspirin 75 mg daily (W/A, 334 patients) or no anticoagulation (C, 334 patients). The mean follow-up period was 33 months. The protocol intended to verify a 37% relative risk reduction provided a 4% stroke incidence in the C group. Results. The stroke incidence was less in the W/A group, although the reduction was not statistically significant (W/A 9.6% versus C 12.3%). Four haemorrhagic strokes were identified, two in each group. Secondary end-points were transient ischaemic attacks (TIA) (W/A 3.3% versus C 4.5%), all cause mortality (W/A 9.3% versus C 10.8%), cardiovascular morbidity (W/A 17.7% versus C 22.2%) and the combination of stroke + TIA (W/A 11.7% versus C 16.5%). Bleedings were documented in 19 versus four patients (W/A 5.7% versus C 1.2%) (P = 0.003), although none fatal. Sinus rhythm (SR) was recorded occasionally in 68 patients (W/A 9.6% versus C 10.8%). The stroke incidence tended to be higher in those with SR than without, 16.2% versus 10.4%. Conclusions. Our results were inconclusive, but consistent with a small beneficial effect of W/A for reduction of stroke and major vascular events in AF patients at moderate risk. The low-dose regiment produced, however, a significantly increased risk of bleedings. Documented SR occasionally recorded may represent a subpopulation that warrants full dose warfarin. [source] Predictive Capability of Left Atrial Size Measured by CT, TEE, and TTE for Recurrence of Atrial Fibrillation Following Radiofrequency Catheter AblationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2010SACHIN S. PARIKH M.D. Background: Recurrence of atrial fibrillation (AF) after radiofrequency catheter ablation (RFCA) has been well established and is in part related to left atrial (LA) size. The purpose of this study was to assess the predictive capability of LA diameter (LAD) and LA volume (LAV) by echocardiography and computed tomography (CT) to determine success in patients undergoing RFCA of AF. Methods: Eighty-eight patients with paroxysmal or persistent AF who had undergone RFCA and had a prior transthoracic echocardiogram (TTE), transesophageal echocardiogram (TEE), and CT were enrolled in the study. TTE LADs and LV ejection fraction as well as TEE LADs and LAVs in three views were recorded. CT LAVs were also recorded. Clinical parameters prior to ablation as well as at 1-year follow-up were assessed. Results: A total of 40 (45%) patients with paroxysmal AF and 48 (55%) patients with persistent AF were analyzed. Paroxysmal AF patients had a RFCA success rate of 88% at 1 year with persistent AF patients having a 52% success rate (P < 0.001). A CT-derived LAV , 117 cc was associated with an odds ratio (OR) for recurrence of 4.8 (95% confidence interval [CI]=[1.4,16.4], P = 0.01) while a LAV ,130 cc was associated with an OR for recurrence of 22.0 (95% CI =[2.5,191.0], P = 0.005) after adjustment for persistent AF. Conclusions: LA dimensions and AF type are highly predictive of AF recurrence following RFCA. LAV by CT has significant predictive benefit over standard LADs in severely enlarged atria even after adjustment for AF type. (PACE 2010; 532,540) [source] Reversal of Atrial Remodeling after Cardioversion of Persistent Atrial Fibrillation Measured with MagnetocardiographyPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2009MIKA LEHTO M.D. Background: Atrial fibrillation (AF) causes electrical, functional, and structural changes in the atria. We examined electrophysiologic remodeling caused by AF and its reversal noninvasively by applying a new atrial signal analysis based on magnetocardiography (MCG). Methods: In 26 patients with persistent AF, MCG, signal-averaged electrocardiography (SAECG), and echocardiography were performed immediately after electrical cardioversion (CV), and repeated after 1 month in 15 patients who remained in sinus rhythm (SR). Twenty-four matched subjects without history of AF served as controls. P-wave duration (Pd) and dispersion (standard deviation of Pd values in individual channels) and root mean square amplitudes of the P wave over the last 40 ms portions (RMS40) were determined. Results: In MCG Pd was longer (122.8 ± 18.2 ms vs 101.5 ± 14.6 ms, P < 0.01) and RMS40 was higher (60.4 ± 28.2 vs 46.9 ± 19.1 fT) in AF patients immediately after CV as compared to the controls. In SAECG Pd dispersion was increased in AF patients. Mitral A-wave velocity and left atrial (LA) contraction were decreased and LA diameter was increased (all P < 0.01). After 1 month, Pd in MCG still remained longer and LA diameter greater (both P < 0.05), while RMS40 in MCG, Pd dispersion in SAECG, mitral A-wave velocity, and LA contraction were recovered. Conclusions: Magnetocardiographically detected atrial electrophysiologic alterations in persistent AF diminish rapidly although incompletely during maintained SR after CV. This might be related to the known early high and late lower, but still existent tendency to AF relapses. [source] Acute and Chronic Pulmonary Vein Reconnection after Atrial Fibrillation Ablation: A Prospective Characterization of Anatomical SitesPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2008KIM RAJAPPAN M.D. Background:Arrhythmia recurrence after atrial fibrillation (AF) ablation is often associated with pulmonary vein reconnection (PVR). We prospectively examined anatomical sites of both acute and chronic PVR. Methods:One hundred and fifty AF patients underwent PV wide encirclement and sites where immediate electrical isolation (EI) occurred were tagged using electroanatomic mapping/CT integration (CartomergeÔ, Biosense Webster, Diamond Bar, CA, USA). After 30 minutes PVs were checked and acute PVR sites marked at reisolation. Chronic PVR sites were marked at the time of repeat procedures. Results:On the left, immediate EI sites were predominantly on the intervenous ridge (IVR) and PV-left atrial appendage (PV-LAA) ridge. On the right they were at the roof, IVR, and floor of the PVs. Ninety-eight of one hundred and fifty patients had PVs checked after >30 minutes. Thirty-two of ninety-eight had acute PVR. This was mostly on the IVR and PV-LAA ridge on the left (88%), and on the roof and IVR on the right (78%). At repeat procedure, 38/39 patients had chronic PVR, predominantly on the IVR (61%) and PV-LAA ridge (21%) on the left, and on the roof, IVR, and floor of the right PVs (79%). There was minimal acute or chronic PVR posteriorly. Acutely PVR occurred close to the immediate EI site 60% of the time, but only 30% of the time chronically. Conclusion:Acute and chronic PVR sites have a preferential distribution. This may be determined by anatomical and technical factors. Knowledge of immediate EI sites may be beneficial acutely, but with chronic PVR a careful survey is required. These findings may help target ablation, improving safety and success. [source] Electrocardiographic Activity before Onset of Postoperative Atrial Fibrillation in Cardiac Surgery PatientsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 11 2008MIRELA OVREIU Ph.D. Background:Electrocardiographic (ECG) characteristics were analyzed in postoperative cardiac surgery patients in an attempt to predict development of new-onset postoperative atrial fibrillation (AF). Methods:Nineteen ECG characteristics were analyzed using computer-based algorithms. The parameters were retrospectively analyzed from ECG signals recorded in postoperative cardiac surgery patients while they were in the cardiovascular intensive care unit (CVICU) at our institution. ECG data from 99 patients (of whom 43 developed postoperative AF) were analyzed. A bootstrap variable selection procedure was applied to select the most important ECG parameters, and a multivariable logistic regression model was developed to classify patients who did and did not develop AF. Results:Premature atrial activity (PAC) was greater in AF patients (P < 0.01). Certain heart rate variability (HRV) and turbulence parameters also differed in patients who did and did not develop AF. In contrast, P-wave morphology was similar in patients with and without AF. Receiver operating curve (ROC) analysis applied to the model produced a C-statistic of 0.904. The model thus correctly classified AF patients with more than a 90% sensitivity and a 70% specificity. Conclusion:Among the 19 ECG parameters analyzed, PAC activity, frequency-domain HRV, and heart rate turbulence parameters were the best discriminators for postoperative AF. [source] Individualized Selection of Pacing Algorithms for the Prevention of Recurrent Atrial Fibrillation: Results from the VIP RegistryPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2006THORSTEN LEWALTER Objectives: The VIP registry investigated the efficacy of preventive pacing algorithm selection in reducing atrial fibrillation (AF) burden. Background: There are few data identifying which patients might benefit most from which preventive pacing algorithms. Methods: Patients, with at least one documented AF episode and a conventional antibradycardia indication for pacemaker therapy, were enrolled. They received pacemakers with AF diagnostics and four preventive algorithms (Selection and PreventAF series, Vitatron). A 3-month Diagnostic Phase with conventional pacing identified a Substrate Group (>70% of AF episodes with <2 premature atrial contractions [PACs] before AF onset) and a Trigger Group (,70% of AF episodes with <2 PACs before AF onset). This was followed by a 3-month Therapeutic Phase where in the Trigger Group algorithms were enabled aimed at avoiding or preventing a PAC and in the Substrate Group continuous atrial overdrive pacing was enabled. Results: One hundred and twenty-six patients were evaluated. In the Trigger Group (n = 73), there was a statistically significant 28% improvement in AF burden (median AF burden: 2.06 hours/day, Diagnostic Phase vs 1.49 hours/day, Therapy Phase; P = 0.03304 signed-rank test), and reduced PAC activity. There was no significant improvement in AF burden in the Substrate Group (median AF burden: 1.82 hours/day, Diagnostic Phase vs 2.38 hours/day, Therapy Phase; P = 0.12095 signed-rank test), and little change in PAC activity. Conclusions: We identified a subgroup of patients for whom the selection of appropriate pacing algorithms, based on individual diagnostic data, translated into a reduced AF burden. Trigger AF patients were more likely responders to preventive pacing algorithms as a result of PAC suppression. [source] Myocardium Extending from the Left Atrium onto the Pulmonary Veins: A Comparison Between Subjects with and Without Atrial FibrillationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2001MINORU TAGAWA TAGAWA, M., et al.: Myocardium Extending from the Left Atrium onto the Pulmonary Veins: A Comparison Between Subjects with and Without Atrial Fibrillation. Rapid discharges from the myocardium extending from the left atrium onto the pulmonary vein (PV) have been shown to initiate AF, and AF may be eradicated by the catheter ablation within the PV. However, if there is any difference in the distribution patterns of the myocardial sleeve onto the PV between the subjects with and without AF is to be determined. Twenty-one autopsied hearts were examined. Eleven patients previously had AF before death and another 10 patients had normal sinus rhythm as confirmed from the medical records including ECGs before death. After exposing the heart, the distance to the peripheral end of the myocardium was measured from the PV-atrial junction in each PV. Then, the PVs were sectioned and stained and the distal end of myocardium and the distribution pattern were studied. The anteroposterior diameter of the left atrium was also measured. In 74 of 84 PVs, the myocardium extended beyond the PV-atrial junction. The myocardium was localized surrounding the vascular smooth muscle layer forming a myocardial sleeve. The peripheral end of the myocardial sleeve was irregular and the maximal and minimal distances were measured in each PV. The myocardium extended most distally in the superior PVs compared to the inferior ones and the maximal distance to the peripheral end was similar between the AF and non-AF subjects (8.4 ± 2.8 vs 8.7 ± 4.4 mm for the left superior and 6.5 ± 3.5 vs 5.1 ± 3.9 mm for the right superior PV, respectively). A significant difference was found in the maximal distance in the inferior PVs: 7.3 ± 4.6 vs 3.3 ± 2.8 mm for the left (P < 0.05) and 5.7 ± 2.4 vs 1.7 ± 1.9 mm for the right inferior PV (P < 0.001) in the subjects with and without AF, respectively. The diameter of left atrium was slightly dilated in AF patients but insignificantly (4.1 ± 0.1 vs 3.6 ± 0.1 cm, P > 0.07). The myocytes on the PV were less uniform and surrounded by more fibrosis in patients with AF compared to those without AF. In conclusion, the myocardium extended beyond the atrium-vein junction onto the PVs. The distribution patterns of the myocardium was almost similar between subjects with and without AF, but the histology suggested variable myocytes in size and fibrosis in patients with AF. [source] Latest news and product developmentsPRESCRIBER, Issue 5 2008Article first published online: 3 APR 200 Newer antidepressants no better than placebo? A new meta-analysis suggests that newer antidepressants are no superior to placebo in most patients with depression , the exception being those with very severe depression, who can expect a small benefit. Writing in the online-only open access journal PLoS Medicine (5:e45.doi:10.1371/ journal.pmed.0050045), researchers from Hull and the US analysed published and unpublished trials submitted to the Food and Drug Administration in marketing applications for fluoxetine, paroxetine, venlafaxine (Efexor) and nefazodone (no longer available). Using the Hamilton Rating Scale for Depression (HRSD) score as an endpoint, meta-analysis of 35 trials involving 5133 patients and lasting six to eight weeks showed that mean HRSD score improved by 9.6 points with drug treatment and 7.8 with placebo. The authors say the difference of 1.8 was statistically significant but below the criterion for clinical significance (3.0) set by NICE in its clinical guideline on depression. A review of the study by the NHS Knowledge Service (www.nhs.uk) points out that it omits trials published after the drugs were licensed (1999) and those not sponsored by the pharmaceutical industry. It did not include any patients with severe depression and only one trial in patients with moderate depression. An earlier US study of data submitted to the FDA (N Eng J Med 2008;358:25260) showed that published trials of antidepressants were more likely to be positive (37/38) than unpublished ones (3/25). Further, FDA analysts concluded that 51 per cent of trials (published and unpublished) demonstrated positive findings compared with 94 per cent of those that were published. Audit reveals variations in hospital psoriasis care There are unacceptably large variations in the quality of care for patients with psoriasis in UK hospitals, a report by the British Association of Dermatologists and the Royal College of Physicians reveals. The audit of 100 hospital units found that 39 per cent restricted access to biological therapies because of cost, and over one-third of pharmacies could not supply ,specials' such as topical coal tar preparations. More positively, the units are adequately resourced to provide timely communication with GPs. RCGP responds to Public Accounts Committee The Royal College of General Practitioners has agreed with the Commons Public Accounts Committee that drug package labelling should include the cost of the medication. The suggestion was made by the Committee in its report Prescribing Costs in Primary Care. While recognising the importance of generic prescribing, the RCGP cautions against frequent medication switches because it may unsettle patients. ,Any changes must be carried out for sound clinical reasons with good communication between GPs and their patients,' it adds. Statins for patients with kidney disease? Statins reduce cardiovascular risk in people with chronic kidney disease, a new study suggests, but their effects on renal function remain unclear (BMJ 2008; published online doi: 10.1136/bmj. 39472.580984.AE). The meta-analysis of 50 trials involving a total of 30 144 patients found that statins reduced lipids and cardiovascular events regardless of the severity of kidney disease. However, all-cause mortality was unaffected and, although proteinuria improved slightly, there was no change in the rate of decline of glomerular filtration rate. An accompanying editorial (BMJ 2008; published online doi:10.1136/ bmj.39483.665139.80) suggests that the indications for statin therapy to reduce cardiovascular risk in patients with chronic kidney disease should be the same as for those with normal renal function. New NICE guidance New clinical guidelines from NICE (see New from NICE, pages 14,15) include the diagnosis and management of irritable bowel syndrome in adults in primary care, the care and management of osteoarthritis in adults, and the diagnosis and treatment of prostate cancer. In a public health guideline on smoking cessation services, NICE endorses the use of nicotine replacement patches for 12,17 year olds. Suspect additives in children's medicines The Food Commission (www.foodcomm.org.uk) has drawn attention to the presence in children's medicines of food additives it says are linked with hyperactivity. The Commission, a national nonprofit organisation campaigning for ,the right to safe, wholesome food', says that seven common additives (including tartrazine, sodium benzoate and Ponceau 4R) are associated with hyperactivity in susceptible children. Checking the SPCs, it found that 28 of 70 children's medicines , including formulations of paracetamol, ibuprofen, amoxicillin, erythromycin and codeine phosphate throat linctus , contain at least one suspect additive. Digoxin may increase mortality in AF patients An observational study has suggested that digoxin may increase deaths in patients with atrial fibrillation (Heart 2008;94:191,6). The study was a planned subgroup analysis of a trial evaluating anticoagulant therapy in 7329 patients with atrial fibrillation. Of these, 53 per cent were treated with digoxin. Mortality was significantly higher among digoxin users than nonusers (4.22 vs 2.66 per cent per year); myocardial infarction and other vascular deaths (but not stroke, systemic embolic episodes and major bleeding events) were significantly more frequent with digoxin. Poor communications cause readmission Elderly hospital patients are often discharged with inadequate information or arrangements for care, causing almost three-quarters to be readmitted within a week, say investigators from Nottingham (Qual Safety Health Care 2008;17:71,5). Retrospective review of records for 108 consecutive patients aged over 75 found that readmission was related to medication in 38 per cent and, of these, 61 per cent were considered avoidable. Almost two-thirds had no discharge letter or were readmitted before the letter was typed; two-thirds of discharge letters had incomplete documentation of medication changes. Copyright © 2008 Wiley Interface Ltd [source] Bridging of Chronic Oral Anticoagulation with Enoxaparin in Patients with Atrial Fibrillation: Results from the Prospective BRAVE RegistryCARDIOVASCULAR THERAPEUTICS, Issue 4 2009C. Hammerstingl Current American College of Chest Physicians (ACCP) guidelines on the perioperative management of oral anticoagulation (OAC) suggest bridging therapy with therapeutic doses of low-molecular-weight heparin (LMWH) in patients with atrial fibrillation (AF) if at high or moderate thromboembolic (TE) risk, and with reduced doses in patients with low TE risk. Our objective was to assess the efficacy and safety of bridging OAC with enoxaparin in AF patients. These are the results of an open, prospective monocenter register. Hospitalized and ambulatory patients with AF requiring bridging therapy at high or moderate TE risk and normal renal function were treated with therapeutic LMWH doses; all other patients received reduced doses. A total of 703 patients were enrolled, of whom 358 (50.9%) were at moderate-to-high and 345 (49.1%) at low TE risk. Renal impairment was detected in 308 patients (43.8%). One hundred ninety patients (27.1%) were treated with therapeutic LMWH doses and 513 (72.9%) with reduced doses. No TE events were observed during the follow-up period (0%; 95% confidence interval [CI] 0.0,0.52). Three major bleeds (0.4%; 0.1,1.2) and 60 minor bleeds were noted (8.9%; 6.6,10.9). Age and total LMWH doses were risk factors for bleeding in the multivariate analysis. The study, under conditions of everyday clinical care, supports a predefined bridging regimen based on the individual patient's TE risk and renal function. Patients with low TE risk or with impaired renal function can be bridged effectively and safely with reduced LMWH doses. [source] C,Reactive Protein and Atrial Fibrillation in Idiopathic Dilated CardiomyopathyCLINICAL CARDIOLOGY, Issue 9 2009Shimo MD Background Previous studies have found elevated plasma C-reactive protein (CRP) levels in atrial fibrillation (AF) patients. Most of these studies included AF patients with various heart diseases, but few studies were designed to investigate CRP in idiopathic dilated cardiomyopathy (IDCM) patients with AF. Method and Results CRP levels in 242 IDCM patients with AF were compared with CRP levels in 280 control IDCM patients. Among control patients, 70 had atrial premature beats or atrial tachycardia and 210 had normal sinus rhythm. CRP was higher in the AF group than in the control group (median, 4.59 versus 2.81 mg/L; p < 0.001). The prevalence of AF in IDCM patients increased as plasma CRP levels increased, and the patients with the highest plasma CRP levels had the highest probability of suffering from AF. Outcome of multivariate logistic regression analysis showed body mass index, AF, and white blood cell count significantly correlated with the plasma CRP levels. Conclusion Our data demonstrated that the plasma CRP level in IDCM patients with AF was higher than in IDCM patients without AF, and an increase in plasma CRP levels was associated with an increased prevalence of AF in IDCM patients. Also, body mass index, AF, and white blood cell count correlate with plasma CRP levels in IDCM patients. These data suggest there is presence of inflammation in IDCM patients with AF. Copyright © 2009 Wiley Periodicals, Inc. [source] | ||||||||||