Prediction of the Recurrence of Atrial Fibrillation After Successful Cardioversion with P Wave Signal‐Averaged ECG

Background: The recurrence of atrial fibrillation (AF) was often observed after cardioversion. Methods: In our study, a P wave triggered P wave signal‐averaged ECG (P‐SAECG) was performed on 118 consecutive patients 1 day after successful electrical cardioversion in order to evaluate the utility of this method to predict AF after cardioversion. We measured the filtered P wave duration (FPD) and the root mean square voltage of the last 20 ms of the P wave (RMS 20). Results: During a 1‐year follow‐up, a recurrence was observed in 57 patients (48%). Patients with recurrence of AF had a larger left atrial size (41.9 ± 4.0 vs 39.3 ± 3.1 mm, P < 0.0003), a longer FPD (139.6 ± 16.0 vs 118.2 ± 14.1 ms, P < 0.0001), and a lower RMS 20 (2.57 ± 0.77 vs 3.90 ± 0.99 μV, P < 0.0001). A cutoff point (COP) of FPD ≥126 ms and RMS 20 ≤3.1 μV could predict AF with a specificity of 77%, a sensitivity of 72%, a positive value of 75%, a negative predictive value of 75%, and an accuracy of 75%. A stepwise logistic regression analysis of variables identified COP (odds ratio 9.97; 95% CI, 4.10–24.24, P < 0.0001) as an independent predictor for recurrence. Conclusions: We conclude that the probability of recurrence of AF after cardioversion could be predicted by P‐SAECG. This method seems to be appropriate to demonstrate a delayed atrial conduction that might be a possible risk factor of reinitiation of AF.     

P‐Wave Signal‐Averaged Electrocardiogram Predicts Atrial Fibrillation After Coronary Artery Bypass Grafting

Background: AF is one of the most common complications after CABG. The aim of the study was to identify the risk factors for postoperative AF. Methods: Between June and December 2000, 129 consecutive patients (72 men, 47 women; mean age 67 ± 6 years) underwent preoperative signal‐averaged electrocardiogram (SAECG) with assessment of filtered P‐wave duration (fPWD) and of the root mean square voltage of the last 10 and 20 ms of atrial depolarization (RMSV10 and RMSV20, respectively) before CABG. Results: Fifty‐six (43%) patients developed one episode of AF lasting > 30 seconds at a mean distance of 2.6 ± 1.8 days after surgery (group A), while 73 patients remained in sinus rhythm (group B). No differences between the two groups were found in terms of age, sex, P‐wave duration on the standard ECG, left atrial dimensions, and operative characteristics. In contrast, group A patients showed a significantly longer fPWD (138 ± 10 vs 111 ± 9 ms; P < 0.001) and smaller RMSV10 and RMSV20 (2.8 ± 1.0 vs 4.3 ± 1.1 μV, P < 0.001; 4.2 ± 2.1 vs 6.2 ± 2.0 μV, P < 0.001). Multivariate analysis indicated only fPWD as an independent predictor of AF (P = 0.009). With a cut‐off value of 135 ms for fPWD, the occurrence of AF could be predicted with a sensitivity of 84%, a specificity of 73%, a negative predictive value of 85%, and a positive predictive value of 70%. Conclusion: Preoperative SAECG is a simple exam that correctly identifies patients at higher risk of AF after CABG. A more widespread use of this technique can be suggested. A.N.E. 2002;7(3):198–203     

风湿性心脏病心房颤动患者心房细胞外信号调节蛋白与纤维化的关系

探讨风湿性心脏病 (简称风心病 )心房颤动 (简称房颤 )患者心房组织细胞外信号调节激酶 (ERK)与心房纤维化的关系。 33例风心病二尖瓣病变患者行心脏外科手术时取右心耳组织。通过逆转录 聚合酶链反应和免疫组织化学技术 ,测量ERK2 mRNA和激活的ERK2 蛋白相对表达量 ,测定心房组织血管紧张素Ⅱ (AngⅡ )含量和胶原纤维容积分数 (CVF)。结果 :阵发性和慢性房颤患者的心房组织CVF、AngⅡ均明显高于窦性心律患者 (10 .4 4 %±1.83% ,15 .0 1%± 2 .30 %vs 7.4 8%± 1.2 6 % ;10 .17± 1.73,12 .13± 1.95vs 6 .6 9± 1.18ng/mg,P均 <0 .0 1) ,而慢性房颤患者的CVF、AngⅡ又明显高于阵发性房颤患者 (P <0 .0 1,P <0 .0 5 ) ;阵发性和慢性房颤患者的心房组织ERK2mRNA表达量显著高于窦性心律患者 (1.2 0 9± 0 .2 85 ,1.30 5± 0 .2 6 3vs 0 .92 3± 0 .2 71;P <0 .0 5 ,P <0 .0 1) ,而阵发性和慢性房颤患者之间无明显差别 (P >0 .0 5 ) ;阵发性和慢性房颤患者的心房间质细胞激活的ERK2 蛋白表达量显著高于窦性心律患者 (0 .2 5 2± 0 .0 75 ,0 .2 88± 0 .0 6 3vs 0 .175± 0 .0 74 ;P均 <0 .0 1) ,而阵发性和慢性房颤患者之间无明显差别 (P >0 .0 5 )。结论 :心房间质ERK途径的激活是风心病房颤患者心房纤维     

Correlation of Mechanical Dyssynchrony with QRS Duration Measured by Signal‐Averaged Electrocardiography

Background: Preimplantation left ventricular dyssynchrony is considered a prerequisite for a beneficial response to cardiac resynchronization therapy (CRT). However, electrical dyssynchrony estimated by QRS duration (QRSd) on ECG has not been proven to be an optimal surrogate of mechanical dyssynchrony. We evaluated the correlation of mechanical dyssynchrony with QRSd as measured by signal‐averaged electrocardiography (SAECG) in comparison with measurements based on conventional surface ECG and with onscreen measurements based on digital ECG. Methods: We included 49 consecutive patients with decompensated heart failure (40 men, aged 66.8 ± 9.5 years), New York Heart Association (NYHA) class II–IV, and LVEF ≤ 40%. QRSd was calculated by manual measurement of 12‐lead ECG, on‐screen measurement of computer‐based ECG, and calculation of total ventricular activation time on SAECG. Results: Only 60.4% of the studied patients had QRS ≥ 120 ms based on measurements derived by SAECG compared to 69.4% by using on‐screen measurement of computer‐based ECG and 73.5% based on surface ECG (P = 0.041). Interventricular but not intraventricular delay was correlated with QRSd. The correlation of interventricular dyssynchrony with QRSd was stronger when measured by SAECG than by surface ECG (r = 0.45, P = 0.001 vs r = 0.35, P < 0.01). Among patients with ischemic cardiomyopathy, no significant correlation was demonstrated between mechanical dyssynchrony and QRSd. In nonischemic patients, interventricular delay was significantly correlated with QRSd measured by surface ECG (r = 0.45, P < 0.05) and SAECG (r = 0.46, P < 0.05). Conclusions: The use of SAECG results in different patient classification in wide QRS complex category as compared to surface ECG. Furthermore, QRSd measured by SAECG is correlated with interventricular but not intraventricular dyssynchrony in heart failure patients.     

Long‐Term Outcome of Catheter Ablation in Patients with Atrial Fibrillation Originating from Nonpulmonary Vein Ectopy

Long‐Term Outcome of NPV AF Ablation . Introduction: Data regarding the long‐term outcome of catheter ablation in patients with nonpulmonary vein (NPV) ectopy initiating atrial fibrillation (AF) are limited. We aimed to evaluate the long‐term result of patients with AF who had NPV triggers and underwent catheter ablation. Methods and Results: The study included 660 consecutive patients (age 54 ± 11 years old, 477 males) who had undergone catheter ablation for AF. Group 1 consisted of 132 patients with AF initiating from the NPV, and group 2 consisted of 528 patients with AF initiating from pulmonary vein (PV) triggers only. Patients from Group 1 were younger than those from Group 2 (51 ± 12 years old vs 54 ± 11 years old, P = 0.001) and were more likely to be females (34.4% vs 25.8%, P = 0.049). The incidences of nonparoxysmal AF (36.4% vs 16.3%, P < 0.001) and right atrial (RA) enlargement (31.3% vs 19%, P = 0.004) were higher, and the biatrial substrates were worse in Group 1 than those in Group 2 (left atrial voltage 1.5 ± 0.7 mV vs 1.9 ± 0.7 mV, P < 0.001, RA voltage 1.6 ± 0.5 mV vs 1.8 ± 0.6 mV, P = 0.014). During a follow‐up period of 46 ± 23 months, there was a higher AF recurrence rate in Group 1 than in Group 2 (57.6% vs 38.8%, P < 0.001). The independent predictors of AF recurrence were NPV trigger (P < 0.001, HR 2, 95% CI 1.4–2.85), nonparoxysmal AF (P = 0.021, HR 1.55, 95% CI 1.07–2.24), larger left atrial diameter (P = 0.002, HR 1.04, 95% CI 1.02–1.07) and worse left atrial substrate (P = 0.028, HR 1.3, 95% CI 1.03–1.64). Conclusion: Compared to AF originating from the PV alone, AF originating from the NPV ectopy showed a worse outcome. (J Cardiovasc Electrophysiol, Vol. 24, pp. 250‐258, March 2013)     

A Prospective Study of Atrial Fibrillation After Cardiac Surgery

Background: Atrial fibrillation (AF) is a commonly encountered arrhythmia following cardiac surgery and when sustained, may be associated with significant morbidity. Methods: This large prospective investigation examined a variety of clinical and P wave signal-averaged electrocardiogram (SAECG) parameters to identify independent predictors of AF following cardiac surgery. A total of 272 patients underwent P wave SAECG recording and analysis prior to surgery. Information on their clinical, surgical, and hemodynamic characteristics as well as hospital course was collected. Patients were followed during their postoperative course with telemetry and ECGs. Results: During an observation period of up to 14 days, 79 patients (29%) developed AF 2.5 ± 1.9 days after surgery. Patients who developed AF following cardiac surgery were more likely to be older, undergo valve surgery, to have ejection fraction (EF) < 40%, to have P wave duration on SAECG >140 ms (all P < 0.01), and to take digoxin preoperatively (P < 0.05). A multivariate analysis found that only P wave duration on SAECG >140 ms and EF < 40% were independent predictors of AF following cardiac surgery. The odds ratio of P wave duration on SAECG >140 ms and EF < 40% for the development of AF following cardiac surgery was 3.1 and 2.8, respectively, and 8.7 when combined. Conclusions: Thus, the presence of preexisting abnormal atrial substrate as detected by P wave prolongation on SAECG, and implicated by EF < 40%, clearly predicted a higher risk of AF following cardiac surgery and may provide clinicians with an effective means of identifying those at greatest risk.     

P wave signal-averaged ECG in normal population and in patients with converted atrial fibrillation

Background: Signal‐averaged electrocardiography of the P wave (P wave SAECG) is a noninvasive method for evaluating the risk of atrial fibrillation (AF). We aimed to study P wave SAECG parameters in a large number of apparently healthy subjects and to compare them with patients with converted AF. Methods: We examined 591 individuals; P wave SAECG were recorded in 330 normal subjects, 31 patients with converted persistent AF and 57 patients with converted paroxysmal AF immediately after conversion, at 12 and 24 hours after conversion, then after 3 and 6 months. P wave SAECG were recorded using a commercially available machine aiming to obtain a noise level <1 μV. Results: In the normal population the duration of the filtered P wave (PWD) was higher in men. P wave duration, RMS₄₀ and RMS₃₀ were significantly correlated with age. By comparing the normal population with patients with persistent AF converted to sinus rhythm we demonstrated significant differences in PWD and P wave integral. Patients with recurrent persistent AF had significantly higher PWD. The study of patients with paroxysmal AF, compared to the control group, showed significant increase of the same parameters: PWD and integral of the P wave. Patients with recurrent paroxysmal AF had higher PWD and lower RMS₄₀, RMS₃₀, RMS₂₀. Conclusions: Filtered P wave duration was higher in men; PWD was weakly but significantly correlated with age. Patients with paroxysmal or persistent AF converted to sinus rhythm had significantly higher P wave duration and P wave integral. Ann Noninvasive Electrocardiol 2011;16(4):351–356     

The Impacts of Transcatheter Occlusion for Congenital Atrial Septal Defect on Left Ventricular Systolic Synchronicity: A Three‐Dimensional Echocardiography Study

Objectives: To investigate the impacts of transcatheter occlusion for congenital atrial septal defect (ASD) on left ventricular (LV) systolic synchronicity using a real time three‐dimensional echocardiography (RT3DE). Methods: Thirty patients with ASD closure were recruited for the study. Realtime three‐dimensional echocardiographic data sets were acquired for the measurement of LV volumes LV ejection fractions and LV three‐dimensional systolic synchronicity before and at 6 months after transcatheter occlusion for ASD. M‐mode echocardiography and RT3DE were performed to characterize interventricular septal (IVS) motion. Results: There were no differences in LV systolic synchronicity between before and after transcatheter closure of ASD (Tmsv‐16SD%: 5.6%± 1.4% vs 5.8%± 1.8%, P > 0.05; Tmsv—12SD%: 5.2 ± 1.1% vs 5.4 ± 1.2%, P > 0.05). But the abnormal IVS motion was found before device closure and normalized after transcatheter occlusion for ASD using M‐mode echocardiography and the excursion‐time figure (bull's‐eye derived from RT3DE); At the same time, LV ejection fraction (59.8 ± 2.6 vs 66.7 ± 5.9, P < 0.05) stroke volume (49 ± 14 vs 63 ± 11, P < 0.05) was improved significantly as well as normalization of IVS motion after transcatheter occlusion for ASD. The correlation between ASD diameter and change of LVEF is significant (r = 0.85, P < 0.001). Conclusion: Although transcatheter occlusion did not significantly impact on intrinsic LV systolic synchronicity in patients with ASD, LV systolic function can be improved through normalization of IVS abnormal motion after transcatheter ASD occlusion. (Echocardiography 2010;27:324‐328)     

Ventricular Late Potentials Are Associated with the Presence of Viable Myocardium After Anterior Myocardial Infarction

Background: The aim of the study was to evaluate the relationship between myocardial viability (MV) detected by Tl‐201 rest/redistribution protocol (RR‐SPECT) and the presence of ventricular late potentials (VLPs) in acute myocardial infarction (AMI). We analyzed signal‐averaged ECGs (SAECGs) in 28 patients (age 57 ± 10 years) with a first anterior AMI within 48 hours of symptoms (SAECG1) and prior to discharge (SAECG2). VLPs were defined according to the presence of filtered QRS (QRS‐D) > 114 ms and duration of low amplitude signals (LAS) a 30 ms or root mean square voltage (RMS40) < 25 μ;V, using a 25‐Hz filter, or a duration of LAS > 39 ms or RMS40 < 20 μ;V, using a 40‐Hz filter. RR‐SPECT was performed 17 ± 6 days after AMI. Segments were considered viable when counts were > 60% in early images or when a fill‐in > 10% was detectable on delayed images of those segments with a first count between 31% and 59%. Methods: Patients were divided into two groups: with MV (group 1 = 16 patients) if almost one third of segments appeared to be viable; without MV (group 2 = 12 patients). No difference was found between the two groups in SAECG1, whereas, using a 25‐Hz filter, a greater QRS‐D (106.6 ± 13.5 vs 93.5 ± 6 ms) and LAS (31.2 ± 8.7 vs 18.1 ± 6.4 ms) as well as a smaller RMS40 (43 ± 33.5 vs 71.3 ± 30.4 μ;V) characterized the SAECG2 of group 1. Sensitivity and specificity of VLPs in detecting MV were 31% and 100%. When using cut‐off values derived from median distribution of the population (QRS‐D & 99 ms, LAS a 24 ms and RMS40 > 51 μ;V), sensitivity raised to 75% and specificity was 92% with a positive and negative predictive value of 92% and 73%. Conclusions: The presence of MV is associated with a greater incidence of VLPs. SAECG performed at the time of discharge may facilitate the identification of patients with μ;V after anterior AMI.     

Comparison of ThermoCool® Surround Flow Catheter Versus ThermoCool® Catheter in Achieving Persistent Electrical Isolation of Pulmonary Veins: A Pilot Study

Persistent Electrical Isolation of Pulmonary Veins . Introduction: Aim of this study was to compare efficacy and safety of the new ThermoCool Surround Flow® catheter (SFc) versus the ThermoCool® (TCc) in achieving persistent circumferential electrical isolation of the pulmonary veins (PVs) in patients with paroxysmal atrial fibrillation (AF). Methods and Results: This multicenter, randomized, controlled study enrolled patients suffering from paroxysmal AF. Randomization was run in a one‐to‐one fashion between radiofrequency ablation by TCc or SFc. Aim of PVs ablation was documentation of electrical isolation with exit/entrance block recorded on a circular catheter. Among the 106 enrolled patients, 52 (49.0%) were randomized to TCc and 54 (51.0%) to SFc. Total volume of infused saline solution during the procedure was lower in the SFc than in TCc group (752.7 ± 268.6 mL vs 1,165.9 ± 436.2 mL, P < 0.0001). Number of identified and isolated PVs was similar in the 2 groups. Number of PVs remaining isolated 30 minutes after ablation was higher in the SFc than in TCc group (95.2% vs 90.5%, P < 0.03), mainly driven by acute ablation result in the left PVs (96.1% vs 89.7%, P < 0.04). Complications were seldom and observed only in the TCc group (0% vs 3.84%, P < 0.03). At 6‐month follow‐up SFc patients reported a trend toward less AF recurrences compared to those in the TCc group (22.9% vs 27.0%, P = 0.69). Conclusion: PV isolation by SFc lowered the rate of left PV early reconnections and reduced the volume of infused saline solution while maintaining the safety profile of AF ablation. (J Cardiovasc Electrophysiol, Vol. 24, pp. 269‐273, March 2013)     

Efficacy of adjuvant anterior left atrial ablation during intracardiac echocardiography-guided pulmonary vein antrum isolation for atrial fibrillation

Background: Recent data have shown that the septum and anterior left atrial (LA) wall may contain “rotor” sites required for AF maintenance. However, whether adding ablation of such sites to standard ICE‐guided PVAI improves outcome is not well known. Objective: To determine if adjuvant anterior LA ablation during PVAI improves the cure rate of paroxysmal and permanent AF. Methods: One hundred AF patients (60 paroxysmal, 40 persistent/permanent) undergoing first‐time PVAI were enrolled over three months to receive adjuvant anterior LA ablation (Group I). These patients were compared with 100 randomly selected, matched first‐time PVAI controls from the preceding three months who did not receive adjuvant ablation (Group II). All 200 patients underwent ICE‐guided PVAI during which all four PV antra and SVC were isolated. In group I, a decapolar lasso catheter was used to map the septum and anterior LA wall during AF (induced or spontaneous) for continuous high‐frequency, fractionated electrograms (CFAE). Sites where CFAE were identified were ablated until the local EGM was eliminated. A complete anterior line of block was not a requisite endpoint. Patients were followed up for 12 months. Recurrence was assessed post‐PVAI by symptoms, clinic visits, and Holter at 3, 6, and 12 months. Patients also wore rhythm transmitters for the first 3 months. Recurrence was any AF/AFL >1 min occurring >2 months post‐PVAI. Results: Patients (age 56 ± 11 years, 37% female, EF 53%± 11%) did not differ in baseline characteristics between group I and II by design. Group I patients had longer procedure time (188 ± 45 min vs 162 ± 37 min) and RF duration (57 ± 12 min vs 44 ± 20 min) than group II (P < 0.05 for both). Overall recurrence occurred in 15/100 (15%) in group I and 20/100 (20%) in group II (P = 0.054). Success rates did not differ for paroxysmal patients between group I and II (87% vs 85%, respectively). However, for persistent/permanent patients, group I had a higher success rate compared with group II (82% vs 72%, P = 0.047). Conclusions: Adjuvant anterior LA ablation does not appear to impact procedural outcome in patients with paroxysmal AF but may offer benefit to patients with persistent/permanent AF.     

Effect of Reperfusion on P‐Wave Duration and P‐Wave Dispersion in Acute Myocardial Infarction: Primary Angioplasty versus Thrombolytic Therapy

Background: Atrial fibrillation (AF) is a common arrhythmia occurring in about 10–20% of patients with acute myocardial infarction (AMI). P‐wave dispersion (PWd) and P‐wave duration (PWD) have been used to evaluate the discontinuous propagation of sinus impulse and the prolongation of atrial conduction time, respectively. This study was conducted to compare the effects of reperfusion either by thrombolytic therapy or primary angioplasty on P‐wave duration and dispersion in patients with acute anterior wall myocardial infarction. Methods: We have evaluated 72 consecutive patients retrospectively (24 women, 48 men; aged 58 ± 12 years) experiencing acute anterior wall myocardial infarction (AMI) for the first time. Patients were grouped according to the reperfusion therapy received (primary angioplasty (PTCA) versus thrombolytic therapy). Left atrial diameter and left ventricular ejection fraction (LVEF) were determined by echocardiography in all patients. Electrocardiography was recorded from all patients on admission and every day during hospitalization. Maximum (P max) and minimum (P min) P‐wave durations and P‐wave dispersions were calculated before and after the treatment. Results: There were not any significant differences between the groups regarding age, gender, left ventricular ejection fraction, left atrial diameter and volume, cardiovascular risk factors, and duration from symptom onset to treatment. P‐wave dispersions and P‐wave durations were significantly decreased after PTCA [Mean P max was 113 ± 11 ms before and 95 ± 17 ms after the treatment (P = 0.007)]. Mean PWd was 46 ± 12 ms before and 29 ± 10 ms after the treatment (P = 0.001). Also, P max and PWd were significantly lower in PTCA group (for P max 97 ± 22 ms vs 114 ± 16 ms and for PWd 31 ± 13 ms vs 55 ± 5 ms, respectively). Conclusions: Primary angioplasty reduces the incidence of AF by decreasing P max and P‐wave dispersion.     

Maximum P Wave Duration and P Wave Dispersion in Adult Patients with Secundum Atrial Septal Defect: The Impact of Surgical Repair

Background: Patients with atrial septal defect (ASD) have an increased risk for atrial fibrillation (AF). Previously it was shown that maximum P wave duration and P wave dispersion in 12‐lead surface electrocardiograms are significantly increased in individuals with a history of paroxysmal AF. We studied P maximum and P dispersion in adult patients with ASD during normal sinus rhythm. In addition, the impact of surgical closure of ASD on these variables within 1 year after surgery was evaluated. Methods: Thirty‐four patients (21 women, 13 men; mean age: 35 ± 11 years) operated on for ostium secundum type ASD and 24 age‐matched healthy subjects (13 women, 11 men; mean age: 37 ± 10 years) were investigated. P maximum, P minimum, and P dispersion (maximum – minimum P wave duration) were measured from the 12‐lead surface electrocardiography. Results: P maximum was found to be significantly longer in patients with ASD as compared to controls (115.2 ± 9 vs 99.3 ± 14 ms; P < 0.0001). In addition, P dispersion of the patients was significantly higher than controls (37 ± 9 vs 29.8 ± 10 ms; P = 0.003). P minimum was not different between the two groups (P = 0.074). After surgical repair of ASD, 10 patients (29%) experienced one or more episodes of paroxysmal AF. Patients with postoperative AF were older (45 ± 6 vs 30 ± 10 years; P = 0.001), and had a higher preoperative pulmonary artery peak systolic pressure as compared to those without postoperative AF (51 ± 11 vs 31 ± 9 mmHg; P < 0.0001). No significant difference in the pulmonary‐to‐systemic flow ratio was observed preoperatively between the two groups (P = 0.56). P maximum and P dispersion were significantly higher in patients with postoperative paroxysmal AF at baseline and at postoperative first month, sixth month, and first year as compared to those without it (for P maximum P = 0.027, P = 0.014, P = 0.001, P < 0.0001, respectively; for P dispersion P = 0.037, P = 0.026, P = 0.001, P < 0.0001, respectively). In addition, in patients with postoperative AF, no significant changes were detected in both of these P wave indices during postoperative follow‐up. However, in the other group, P maximum and P dispersion were found to be significantly decreased at postoperative 6 months and 1 year as compared to baseline. P minimum was similar throughout the postoperative follow‐up as compared to baseline in both groups. Conclusions: Mechanical and electrical changes in atrial myocardium may cause greater P maximum and P dispersion in patients with ASD. Surgical closure of the ASD can regress these pathological changes of atrial myocardium with a result in decreased P maximum and P dispersion. However, higher P maximum and P dispersion at baseline, which have not decreased after surgery, may be associated with postoperative paroxysmal AF, especially for older patients.     

Complex electrograms within the coronary sinus: time- and frequency-domain characteristics, effects of antral pulmonary vein isolation, and relationship to clinical outcome in patients with paroxysmal and persistent atrial fibrillation

Background: The mechanistic and clinical significance of complex fractionated atrial electrograms (CFAE) in the coronary sinus (CS) has been unclear. Methods and Results: Antral pulmonary vein isolation (APVI) was performed in 77 patients with paroxysmal (32) or persistent AF (45). CS electrograms recorded for 60 seconds before and after APVI were analyzed in the time‐ and frequency‐domains. Dominant frequency (DF), complexity index (CI: change in polarity of depolarization), and fractionation index (FI: change in direction of depolarization slope) were determined. Before APVI, there was no difference in DF, CI, or FI between paroxysmal and persistent AF. APVI resulted in a significant decrease in DF, CI, and FI in all patients. Baseline CI (43 ± 13/s vs 54 ± 14/s, P = 0.03) and FI (64 ± 23/s vs 87 ± 30/s, P = 0.02) were lower in patients with paroxysmal AF who had AF terminated by ablation than who did not. At 10 ± 2 months, 69% of patients with paroxysmal AF and 49% of patients with persistent AF were free from AF after single ablation. Baseline CI was higher among patients with paroxysmal AF who had AF after APVI (56 ± 20/s vs 44 ± 10/s, P = 0.03). In patients with persistent AF, there was a larger decrease in DF after APVI among patients who remained free from AF (13 ± 11% vs 7 ± 9%, P < 0.05). Conclusions: Complexity of CS electrograms may reflect drivers of AF that perpetuate paroxysmal AF after APVI. In persistent AF, the extent to which APVI decreases DF in the CS correlates with efficacy, suggesting that DF identifies patients who may require additional ablation beyond APVI.     

P Wave Dispersion and P Wave Duration on SAECG in Predicting Atrial Fibrillation in Patients with Acute Myocardial Infarction

Background: Atrial fibrillation (AF) is a frequent complication of acute myocardial infarction (AMI), with reported incidence of 7% to 18%. The incidence of congestive heart failure, in‐hospital mortality, and long‐term mortality is higher in AMI patients with AF than in AMI patients without AF. P wave duration on signal‐averaged ECG (PWD) and P wave dispersion on standard ECG (Pd) are noninvasive markers of intra‐atrial conduction disturbances, which are believed to be the main electrophysiological cause of AF. Methods: In the present study we investigated prospectively whether P wave duration on SAECG and P wave dispersion on standard ECG can predict development of AF in a group of patients with AMI. One hundred and thirty patients (100 men and 30 women, aged 56.9 ± 12) with AMI were investigated. PWD, Pd, their clinical and hemodynamic characteristics were collected. Results: During the observation up to 14 days, 22 patients (16.9%) developed AF. Univariate analysis variables associated with development of AF: age > 65 years, Killip class III‐IV, PWD > 125 ms, and Pd > 25 ms. Stepwise logistic regression analysis showed that age > 65 years, PWD > 125 ms, and Pd > 25 ms were independently associated with AF. Conclusions: PWD and Pd both measured in a very early period of AMI are useful in predicting AF. A.N.E. 2002;7(4):363–368     

The Relation between the Color M‐Mode Propagation Velocity of the Descending Aorta and Coronary and Carotid Atherosclerosis and Flow‐Mediated Dilatation

Background: To improve clinical outcomes, noninvasive imaging modalities have been proposed to measure and monitor atherosclerosis. Common carotid intima‐media thickness (CIMT) and brachial artery flow‐mediated dilatation (FMD) have correlated with coronary atherosclerosis. Recently, the color M‐mode‐derived propagation velocity of descending thoracic aorta (AVP) was shown to be associated with coronary artery disease (CAD). Methods: CIMT, FMD, and AVP were measured in 92 patients with CAD and 70 patients having normal coronary arteries (NCA) detected by coronary angiography. Patients with acute myocardial infarction, renal failure or hepatic failure, aneurysm of aorta, severe valvular heart disease, left ventricular ejection fraction <40%, atrial fibrillation, frequent premature beats, left bundle branch block, and inadequate echocardiographic image quality were excluded. Results: Compared to patients with normal coronary arteries, patients having CAD had significantly lower AVP (29.9 ± 8.1 vs. 47.5 ± 16.8 cm/sec, P < 0.001) and FMD (5.3 ± 1.9 vs. 11.4 ± 5.8%, P < 0.001) and higher CIMT (0.94 ± 0.05 vs. 0.83 ± 0.14 mm, P < 0.001) measurements. There were significant correlations between AVP and CIMT (r =−0.691, P < 0.001), AVP and FMD (r = 0.514, P < 0.001) and FMD and CIMT (r =−0.530, P < 0.001). Conclusions: The transthoracic echocardiographic determination of the color M‐mode propagation velocity of the descending aorta is a simple practical method and correlates well with the presence of carotid and coronary atherosclerosis and brachial endothelial function. (Echocardiography 2010;27:300‐305)     

Immediate and Long‐term Results Following Balloon Mitral Valvotomy in Patients With Atrial Fibrillation

Background:

The purpose of this study was to examine the influence of atrial fibrillation (AF) on the immediate and long‐term outcome of patients undergoing balloon mitral valvotomy (BMV).

Hypothesis:

Patients with atrial fibrillation fair poorly after balloon mitral valvotomy.

Methods:

There were a total of 818 consecutive patients who underwent elective BMV in this institute from 1997 to 2003, with either double‐lumen or triple‐lumen BMV catheters included in the study. Of them, 95 were with AF. The clinical, echocardiographic, and hemodynamic data of these patients were compared with those of 723 patients in normal sinus rhythm (NSR). Immediate procedural results and long‐term events were compared between the 2 study groups.

Results:

Patients with AF were older (39.9 ± 9.9 years vs 29.4 ± 10.1, P < 0.001) and presented more frequently with New York Heart Association (NYHA) class III‐IV (53.7% vs 32.9%, P < 0.001), echocardiographic score >8 (47.4% vs 24.9%, P < 0.001), and with history of previous surgical commissurotomy (33.7% vs 11.5%, P < 0.001). In patients with AF, BMV resulted in inferior immediate and long‐term outcomes, as reflected in a lesser post‐BMV mitral valve area (1.3 ± 0.4 vs 1.6 ± 0.4 cm 2. , P = 0.032) and higher event rate on follow‐up.

Conclusions:

Patients with AF were older, sicker, and had advanced rheumatic mitral valve disease. They had a higher incidence of stroke, new onset heart failure, and need for reinterventions on long‐term follow‐up. These patients need intense and more frequent follow‐up. Clin. Cardiol. 2011 DOI: 10.1002/clc.22068 The authors have no funding, financial relationships, or conflicts of interest to disclose.     

Factors Associated with the Development of Atrial Fibrillation in COPD Patients: The Role of P‐Wave Dispersion

Background: Supraventricular tachyarrhythmia is a common problem in chronic obstructive pulmonary disease (COPD) patients. The purpose of this study is to analyze the factors associated with paroxysmal atrial fibrillation (AF) in COPD patients. Methods: Forty COPD patients (38 male, 2 female, mean age 60 ± 9 years) and 33 healthy controls (29 male, 4 female, mean age: 58 ± 10 years) were included in this study. Echocardiography, 24‐hour ambulatory and 12‐lead ECG, pulmonary function tests, arterial blood gases, and serum electrolytes were measured. On ECG, maximum (P_max) and minimum (P_min) duration of P wave and its difference, P‐wave dispersion (PWd), were measured. Results: On echocardiography, diastolic dysfunction was found in 14 of the 40 (35%) COPD patients. Heart rate variability analysis revealed that COPD patients had decreased SDANN, SDNN, SDNNIDX in time‐domain, and decreased LF in frequency domain parameters. Fourteen of the 40 COPD patients (35%) had AF. Patients with AF were older (57 ± 10 vs 64 ± 5 years, P = 0.03) and had lower SDANN, SDNN, and LF/HF ratio as compared to patients without AF in univariate analysis. All P‐wave intervals (P_max P_min and PWd) were increased in COPD patients compared to controls. P‐wave dispersion was significantly increased in COPD patients with AF, as compared to patients without AF (57 ± 11 vs 44 ± 7 ms, P = 0.001). In logistic regression analysis PWd was found to be the only factor associated with the development of AF (P = 0.04). Conclusions: The presence of AF was significantly related to the prolongation of PWd, but not with pulmonary function, arterial blood gasses, and left and right atrial function. A.N.E. 2002;7(3):222–227     

Xanthine Oxidase Inhibition Prevents Atrial Fibrillation in a Canine Model of Atrial Pacing‐Induced left Ventricular Dysfunction

Allopurinol and Atrial Fibrillation . Aims: Oxidative stress could be a possible mechanism and a therapeutic target of atrial fibrillation (AF). Xanthine oxidase (XO) inhibition reduces oxidative stress, but the effects of XO inhibitor on AF have not been evaluated. Hence, we assessed the effects of XO inhibitor, allopurinol, on progression of atrial vulnerability in dogs associated with tachycardia‐induced cardiomyopathy. Methods and Results: The dogs were subjected to atrial tachypacing (ATP, 400 bpm) without atrioventricular block for 4 weeks. The dynamics of atrial‐tachycardia remodeling were evaluated in allopurinol‐treated dogs (ALO, n = 5), placebo‐treated controls (CTL, n = 6), and sham‐operated dogs (n = 6). In CTL dogs, 4 weeks of ATP significantly increased AF duration (DAF; from 0.2 ± 0.2 seconds to 173 ± 67 seconds, P < 0.05) and decreased atrial effective refractory period (ERP; from 152 ± 9 milliseconds to 80 ± 4 milliseconds at a cycle length of 350 milliseconds, P < 0.01). Allopurinol attenuated the ATP effects on ERP (118 ± 6 milliseconds, P < 0.01) or DAF (0.6 ± 0.3 seconds, P < 0.05). In CTL dogs, ATP‐induced rapid ventricular responses decreased left ventricular ejection fraction (LVEF; from 58.6 ± 0.1 to 23.5 ± 2.4%, P < 0.01), and increased left atrial diameter (LAD; from 17 ± 1 mm to 24 ± 1 mm, P < 0.01). ATP increased atrial fibrosis when compared with sham‐operated dogs (CTL 10.7 ± 0.8% vs Sham 1.1 ± 0.3%, P < 0.01). Allopurinol suppressed atrial fibrosis (2.3 ± 0.6%, P < 0.01 vs CTL) and eNOS reduction without affecting LVEF (20.6 ± 2.2%, ns) and LAD (23 ± 1 mm, ns). Conclusion: Allopurinol suppresses AF promotion by preventing both electrical and structural remodeling. These results suggest that XO may play an important role in enhancement of atrial vulnerability, and might be a novel target of AF therapy. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1130‐1135, October 2012)     

Effects and Significance of Premature Beats on Fractal Correlation Properties of R‐R Interval Dynamics

Background: Premature beats (PBs) have been considered as artifacts producing a bias in the traditional analysis of heart rate (HR) variability. We assessed the effects and significance of PBs on fractal scaling exponents in healthy subjects and patients with a recent myocardial infarction (AMI). Methods: Artificial PBs were first generated into a time series of pure sinus beats in 20 healthy subjects and 20 post‐AMI patients. Thereafter, a case‐control approach was used to compare the prognostic significance of edited and nonedited fractal scaling exponents in a random elderly population and in a post‐AMI population. Detrended fluctuation analysis (DFA) was used to measure the short‐term (α₁) and long‐term (α₂) fractal scaling exponents. Results: Artificial PBs caused a more pronounced reduction of α₁ value among the post‐AMI patients than the healthy subjects, for example, if >0.25% of the beats were premature a >25% decrease in the α₁ was observed in post‐AMI patients, but 4% of the premature beats were needed to cause a 25% reduction in α₁ in healthy subjects. Both edited (1.01 ± 0.31 vs 1.19 ± 0.27, P < 0.01) and unedited α₁ (0.71 ± 0.33 vs 0.89 ± 0.36, P < 0.05) differed between the patients who died (n = 42) and those who survived (n = 42) after an AMI. In the general population, only unedited α₁ differed significantly between survivors and those who died (0.96 ± 0.19 vs 0.83 ± 0.27, P < 0.05). Conclusions: Unedited premature beats result in an increase in the randomness of short‐term R‐R interval dynamics, particularly in post‐AMI patients. Premature beats must not necessarily be edited when fractal analysis is used for risk stratification.