Signal-averaged P-wave Duration Research Articles

Electrocardiogram characteristics of P wave associated with successful pulmonary vein isolation in patients with paroxysmal atrial fibrillation: Significance of changes in P-wave duration and notched P wave.

BackgroundThe mechanisms involved in changes in P wave following catheter ablation for atrial fibrillation (AF) are uncertain. This study aimed to assess the relationship between changes in P‐wave morphology and pulmonary vein (PV) reconnection following ablation by the assessment of 12‐lead surface electrocardiogram and signal‐averaged electrocardiogram.MethodsThis retrospective study included 115 consecutive patients with paroxysmal AF that underwent repeat ablation for recurrence following initial ablation. We investigated changes in P‐wave morphology between baseline and repeat procedure in patients with and without PV reconnection. The study also included as validation group without recurrence (n = 67) following initial ablation.ResultsThe maximum P‐wave duration (PWD) was significantly decreased from baseline to just after the procedure in all groups. However, for the PV reconnection group (n = 100), the maximum PWD was significantly increased again at the repeat procedure. In contrast, the maximum PWD was significantly reduced between baseline and repeat procedure in the non‐PV reconnection group (n = 15). The signal‐averaged PWD was significantly decreased from baseline to repeat procedure in the non‐PV reconnection group, but, conversely, was increased in the PV reconnection group. In the non‐PV reconnection group, the disappearance of notched P wave was detected in 8 of 15 patients (53%), which was significantly higher than in other groups (p = .001). A new or delayed notched P wave was identified in the PV reconnection group only. These results were confirmed in the validation group.ConclusionsThe reverse dynamics of PWD after initial shortening directly following ablation were significantly associated with PV reconnection.

Electrophysiological abnormalities in patients with paroxysmal atrial fibrillation in the absence of overt structural heart disease

PurposeThe aim of the present study was to define the atrial electrical substrate in patients with paroxysmal atrial fibrillation (AF) occurring in the absence of overt structural heart disease and to assess if electrophysiological parameters could predict AF recurrence after radiofrequency ablation in this population. Methods and results45 consecutive patients (39 male, age 59 ± 10 years) with paroxysmal AF and without overt structural heart disease, referred for radiofrequency catheter ablation, were prospectively enrolled. A cohort of 12 age-matched patients without a history of AF, served as a control group. Atrial electrical substrate was assessed by P-wave signal-averaging, intracardiac conduction delays and refractory periods. Total P wave duration during signal-averaging was longer in patients with paroxysmal AF than in controls (140 ± 19 ms vs 123 ± 13 ms, p = 0.004). Patients with paroxysmal AF showed an increase in right intra-atrial (40.2 ± 11.3 ms vs 31.7 ± 11.8 ms, p = 0.02) and inter-atrial conduction delays (87.93 ± 22.0 ms vs 65.3 ± 15.6 ms, p = 0.001) in sinus rhythm. Refractory periods in the right atrium were longer in patients with paroxysmal AF (265 ± 44 ms vs 222 ± 32 ms, p = 0.002). After ablation, 22 patients had AF recurrence but showed no differences in electrophysiological parameters compared to patients without recurrence. ConclusionElectrophysiological abnormalities are present in patients with paroxysmal AF without overt structural heart disease. Neither signal-averaged P-wave duration nor intracardiac atrial electrophysiology could predict arrhythmia recurrence after pulmonary vein isolation.

Masked hypertension and cardiac remodeling in middle-aged endurance athletes.

Extensive endurance training and arterial hypertension are established risk factors for atrial fibrillation. We aimed to assess the proportion of masked hypertension in endurance athletes and the impact on cardiac remodeling, mechanics, and supraventricular tachycardias (SVT). Male participants of a 10-mile race were recruited and included if office blood pressure was normal (<140/90 mmHg). Athletes were stratified into a masked hypertension and normotension group by ambulatory blood pressure. Primary endpoint was diastolic function, expressed as peak early diastolic mitral annulus velocity (E'). Left ventricular global strain, left ventricular mass/volume ratio, left atrial volume index, signal-averaged P-wave duration (SAPWD), and SVT during 24-h Holter monitoring were recorded. From 108 runners recruited, 87 were included in the final analysis. Thirty-three (38%) had masked hypertension. The mean age was 42 ± 8 years. Groups did not differ with respect to age, body composition, cumulative training hours, and 10-mile race time. Athletes with masked hypertension had a lower E' and a higher left ventricular mass/volume ratio. Left ventricular global strain, left atrial volume index, SAPWD, and SVT showed no significant differences between the groups. In multiple linear regression analysis, masked hypertension was independently associated with E' (beta = -0.270, P = 0.004) and left ventricular mass/volume ratio (beta = 0.206, P = 0.049). Cumulative training hours was the only independent predictor for left atrial volume index (beta = 0.474, P < 0.001) and SAPWD (beta = 0.481, P < 0.001). In our study, a relevant proportion of middle-aged athletes had masked hypertension, associated with a lower diastolic function and a higher left ventricular mass/volume ratio, but unrelated to left ventricular systolic function, atrial remodeling, or SVT.

Effect of lifetime endurance training on left atrial mechanical function and on the risk of atrial fibrillation

Background: Left atrial (LA) dilation and prolongation of the signal-averaged P-wave duration (SAPWD) are linked to the amount and intensity of training. There is growing evidence that this atrial anatomical and electrical remodeling could be the substrate for the increased risk of atrial fibrillation (AF) observed in retrospective cohort studies of athletes. The aim of this study was to evaluate the impact of LA anatomical and electrical remodeling, in the context of lifetime exercise endurance training, on its passive (conduit) and active (pump) function measured by 2-D speckle tracking echocardiography (STE), and to find a link between LA functional adaptation and AF. Methods: Amateur male runners ≥30 years old were recruited (n=109) and, after exclusion of subjects having an office blood pressure >140/90mmHg or other cardiovascular risk factors, stratified in 3 groups according to lifetime training hours: low ( 4'500 h, n=30). Baseline examination consisted of an ECG with analysis of the SAPWD, Doppler echocardiography including STE, 24-hour ambulatory ECG and BP monitoring. Results: No differences were found, between the groups, in terms of age, BP, and diastolic function. LA maximal volume index (30±5, 33±5 vs. 37±6ml/m2, p<0.001), and conduit volume index (9±3, 11±3 vs. 12±3ml/m2, p<0.001) increased significantly from the low to the high training group, unlike the STE parameters which were comparable between the groups: strain pump -15.0±2.8, -14.7±2.7 vs. -14.9±2.6%, p=0.927; strain conduit 23.3±3.9, 22.1±5.3 vs. 23.7±5.7%, p=0.455. Independent predictors of LA strain conduit function were age, maximal early diastolic velocity of the mitral annulus, heart rate and peak early diastolic filling velocity. Left ventricular end diastolic volume index and stroke volume index both increased significantly with lifetime training hours. SAPWD (135±11, 139±10 vs. 148±14ms, p<0.001) and the number of premature atrial contractions (3 [1-7], 6 [2-12], 9 [3-26], p=0.008) increased from the low to the high training group. In one runner of the high training group 4 episodes of non-sustained AF were recorded. Conclusions: The LA anatomical and electrical remodeling does not have a negative impact on atrial mechanical function. LA enlargement may be an adaptation to volume overload, which permits a greater volume delivery to the simultaneously dilating left ventricle. A possible link between these risk factors for AF and its actual, rare occurrence in this athlete population, could not be uncovered in the present study.

Effects of Obstructive Sleep Apnea and its Treatment on Signal-Averaged P-Wave Duration in Men

Prolonged P-wave duration, indicating atrial conduction delay, is a potent precursor of atrial fibrillation. Obstructive sleep apnea (OSA) is a risk factor for atrial fibrillation development. We investigated the association of P-wave duration with OSA and its treatment. We enrolled 80 consecutive men with normal sinus rhythms who underwent polysomnography, had no history of atrial fibrillation or ischemic heart disease, and no evidence of heart failure. Signal-averaged P-wave duration (SAPWD) was measured in all participants. Multivariable regression analysis showed that age, hypertension, and log-transformed apnea-hypopnea index were significantly and independently correlated with SAPWD. SAPWD was repeatedly measured after 1 month of continuous positive airway pressure (CPAP) therapy in 62 patients with moderate-to-severe OSA. As controls, 18 patients with moderate-to-severe OSA were enrolled. Their SAPWD was also measured at baseline and after 1 month without CPAP therapy. No significant change in SAPWD was found between baseline and after 1 month in the controls. However, SAPWD was significantly shortened after 1 month of CPAP therapy (from 137.5±8.6 to 129.7±8.5 ms; P<0.001), and the SAPWD change was significantly different in patients with CPAP therapy compared with controls (P<0.001). In addition, the SAPWD change in patients with CPAP therapy correlated inversely with nightly CPAP usage (r=-0.52; P<0.001). OSA severity was significantly associated with prolonged SAPWD. CPAP therapy significantly shortened SAPWD in patients with moderate-to-severe OSA. Thus, OSA may cause atrial conduction disturbances, leading to an increased risk of atrial fibrillation development, which may be modifiable by alleviating OSA with CPAP therapy.

Inflammation and atrial remodeling after a mountain marathon

Endurance athletes have an increased risk of atrial fibrillation. We performed a longitudinal study on elite runners of the 2010 Jungfrau Marathon, a Swiss mountain marathon, to determine acute effects of long-distance running on the atrial myocardium. Ten healthy male athletes were included and examined 9 to 1 week prior to the race, immediately after, and 1, 5, and 8 days after the race. Mean age was 34.9 ± 4.2 years, and maximum oxygen consumption was 66.8 ± 5.8 mL/kg*min. Mean race time was 243.9 ± 17.7 min. Electrocardiographic-determined signal-averaged P-wave duration (SAPWD) increased significantly after the race and returned to baseline levels during follow-up (128.7 ± 10.9 vs. 137.6 ± 9.8 vs. 131.5 ± 8.6 ms; P < 0.001). Left and right atrial volumes showed no significant differences over time, and there were no correlations of atrial volumes and SAPWD. Prolongation of the SAPWD was accompanied by a transient increase in levels of high-sensitivity C-reactive protein, proinflammatory cytokines, total leucocytes, neutrophil granulocytes, pro atrial natriuretic peptide and high-sensitivity troponin. In conclusion, marathon running was associated with a transient conduction delay in the atria, acute inflammation and increased atrial wall tension. This may reflect exercise-induced atrial myocardial edema and may contribute to atrial remodeling over time, generating a substrate for atrial arrhythmias.

Reverse atrial electrical remodelling induced by continuous positive airway pressure in patients with severe obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is associated with cardiovascular morbidity and mortality, including atrial arrhythmias. Continuous positive airway pressure (CPAP) is the gold standard treatment for OSA; its impact on atrial electrical remodelling has not been fully investigated. Signal-averaged p-wave (SAPW) duration is an accepted marker for atrial electrical remodelling. The objective of this study is to determine whether CPAP induces reverse atrial electrical remodelling in patients with severe OSA. Consecutive patients attending the Sleep Disorder Clinic at Kingston General Hospital underwent full polysomnography. OSA-negative controls and severe OSA were defined as apnoea-hypopnea index (AHI) < 5 events/hour and AHI ≥ 30 events/hour, respectively. SAPW duration was determined at baseline and after 4-6 weeks of CPAP in severe OSA patients or without intervention controls. Nineteen severe OSA patients and 10 controls were included in the analysis. Mean AHI and minimum oxygen saturation were 41.4 ± 10.1 events/hour and 80.5 ± 6.5 % in severe OSA patients and 2.8 ± 1.2 events/hour and 91.4 ± 2.1 % in controls. At baseline, severe OSA patients had a greater SAPW duration than controls (131.9 ± 10.4 vs 122.8 ± 10.5 ms; p = 0.02). After CPAP, there was a significant reduction of SAPW duration in severe OSA patients (131.9 ± 10.4 to 126.2 ± 8.8 ms; p < 0.001), while SAPW duration did not change after 4-6 weeks in controls. CPAP induced reverse atrial electrical remodelling in patients with severe OSA as represented by a significant reduction in SAPW duration.

Gender Differences of Atrial and Ventricular Remodeling and Autonomic Tone in Nonelite Athletes

Veteran endurance athletes have an increased risk of developing atrial fibrillation (AF), with a striking male predominance. We hypothesized that male athletes were more prone to atrial and ventricular remodeling and investigated the signal-averaged P wave and factors that promote the occurrence of AF. Nonelite athletes scheduled to participate in the 2010 Grand Prix of Bern, a 10-mile race, were invited. Of the 873 marathon and nonmarathon runners who were willing to participate, 68 female and 70 male athletes were randomly selected. The runners with cardiovascular disease or elevated blood pressure (>140/90 mm Hg) were excluded. Thus, 121 athletes were entered into the final analysis. Their mean age was 42 ± 7 years. No gender differences were found for age, lifetime training hours, or race time. The male athletes had a significantly longer signal-averaged P-wave duration (136 ± 12 vs 122 ± 10 ms; p <0.001). The left atrial volume was larger in the male athletes (56 ± 13 vs 49 ± 10 ml; p = 0.001), while left atrial volume index showed no differences (29 ± 7 vs 30 ± 6 ml/m²; p = 0.332). In male athletes, the left ventricular mass index (107 ± 17 vs 86 ± 16 g/m²; p <0.001) and relative wall thickness (0.44 ± 0.06 vs 0.41 ± 0.07; p = 0.004) were greater. No differences were found in the left ventricular ejection fraction (63 ± 4% vs 66 ± 6%; p = 0.112) and mitral annular tissue Doppler e' velocity (10.9 ± 1.5 vs 10.6 ± 1.5 cm/s; p = 0.187). However, the tissue Doppler a' velocity was higher (8.7 ± 1.2 vs 7.6 ± 1.3 cm/s; p < 0.001) in the male athletes. Male athletes had a higher systolic blood pressure at rest (123 ± 9 vs 110 ± 11 mm Hg; p < 0.001) and at peak exercise (180 ± 15 vs 169 ± 19 mm Hg; p = 0.001). In the frequency domain analysis of heart rate variability, the sympatho-vagal balance, represented by the low/high-frequency power ratio, was significantly greater in male athletes (5.8 ± 2.8 vs 3.9 ± 1.9; p < 0.001). Four athletes (3.3%) had at least one documented episode of paroxysmal AF, all were men (p = 0.042). In conclusion, for a comparable amount of training and performance, male athletes showed a more pronounced atrial remodeling, a concentric type of ventricular remodeling, and an altered diastolic function. A higher blood pressure at rest and during exercise and a higher sympathetic tone might be causal. The altered left atrial substrate might facilitate the occurrence of AF.

Atrial Remodeling, Autonomic Tone, and Lifetime Training Hours in Nonelite Athletes

Endurance athletes have an increased risk of developing atrial fibrillation (AF) at 40 to 50 years of age. Signal-averaged P-wave analysis has been used for identifying patients at risk for AF. We evaluated the impact of lifetime training hours on signal-averaged P-wave duration and modifying factors. Nonelite men athletes scheduled to participate in the 2010 Grand Prix of Bern, a 10-mile race, were invited. Four hundred ninety-two marathon and nonmarathon runners applied for participation, 70 were randomly selected, and 60 entered the final analysis. Subjects were stratified according to their lifetime training hours (average endurance and strength training hours per week × 52 × training years) in low (<1,500 hours), medium (1,500 to 4,500 hours), and high (>4,500 hours) training groups. Mean age was 42 ± 7 years. From low to high training groups signal-averaged P-wave duration increased from 131 ± 6 to 142 ± 13 ms (p = 0.026), and left atrial volume increased from 24.8 ± 4.6 to 33.1 ± 6.2 ml/m(2) (p = 0.001). Parasympathetic tone expressed as root of the mean squared differences of successive normal-to-normal intervals increased from 34 ± 13 to 47 ± 16 ms (p = 0.002), and premature atrial contractions increased from 6.1 ± 7.4 to 10.8 ± 7.7 per 24 hours (p = 0.026). Left ventricular mass increased from 100.7 ± 9.0 to 117.1 ± 18.2 g/m(2) (p = 0.002). Left ventricular systolic and diastolic function and blood pressure at rest were normal in all athletes and showed no differences among training groups. Four athletes (6.7%) had a history of paroxysmal AF, as did 1 athlete in the medium training group and 3 athletes in the high training group (p = 0.252). In conclusion, in nonelite men athletes lifetime training hours are associated with prolongation of signal-averaged P-wave duration and an increase in left atrial volume. The altered left atrial substrate may facilitate occurrence of AF. Increased vagal tone and atrial ectopy may serve as modifying and triggering factors.

Evaluation of the Relationship between Atrial Septal Aneurysm and Cardiac Arrhythmias via P‐Wave Dispersion and Signal‐Averaged P‐Wave Duration

The aim of the study was to investigate the relationship between atrial septal aneurysms (ASAs) and cardiac arrhythmias via signal-averaged P-wave duration (SAPWD) and P-wave dispersion (Pd). Sixty-six patients with ASA served as the study group (group 1; 28 men and 38 women; mean age, 34 +/- 10 years) and 62 healthy volunteers served as the control group (group 2; 29 men and 33 women; mean age, 31 +/- 8 years) in the current study. ASAs were diagnosed by transthoracic echocardiography based on the criteria of a minimal aneurysmal base of > or =15 mm; and an excursion of > or =10 mm. All subjects were evaluated by 24-hour Holter monitoring, 12 lead body surface electrocardiogram for P-wave analysis, and signal-averaged electrocardiogram for P-wave duration (PWD). There was no significant difference between the study and control groups in terms of age, gender, left atrium diameter, and left ventricular ejection fraction. Supraventricular arrhythmias (SVAs) were detected in 29 patients with ASA (43.9%) and 5 controls (8.1%; P < 0.001). The mean Pd in patients with ASA was significantly longer compared to the control group (14.1 +/- 8 ms vs 7.0 +/- 2.9 ms; P < 0.001). Similarly, the mean SAPWD in group 1 was significantly longer compared to group 2 (127.4 +/- 17.6 ms vs 99.8 +/- 12.3 ms; P < 0.001). Prolonged SAPWD and Pd were determined to indicate electrical disturbances in the atrial myocardium, and predict the increase in the prevalence of SVA in patients with ASA.

Right ventricular apical lead position is associated with prolonged signal-averaged P-wave duration

Aim The study aimed to determine if right ventricular apical pacing is associated with adverse change in atrial substrate compared with right ventricular septal pacing. Methods Patients with septal leads and dual-chamber devices with more than 3 months of follow-up and 70% or higher cumulative percentage of ventricular pacing were compared with a matched group of apically implanted leads with a cumulative percentage ventricular pacing of 70% or higher. Device parameters were recorded, and high-resolution recordings were obtained for signal-averaged P-wave (SAPW) analysis. Previously obtained SAPW recordings taken from 49 healthy patients and 73 patients with paroxysmal atrial fibrillation were used as negative and positive controls, respectively. Results Ten patients with septal leads (mean age, 71.9 ± 12.1 years; mean months implanted, 10.5 ± 3.2 months) and 9 patients with apical leads (mean age, 71.9 ± 5.7 years; mean months implanted, 11.4 ± 6.4 months) were enrolled. The SAPW duration was longer in the apical cohort compared with the septal cohort (144.8 ± 6.9 and 133.0 ± 5.5 milliseconds, respectively; P = .001), whereas there was no significant difference between septal and normal cohorts (133.0 ± 5.5 and 129.3 ± 7.1 milliseconds, respectively; P = .08). Conclusions Apical pacing is associated with prolonged P-wave duration relative to septal pacing and controls: this may manifest as increased risk of atrial tachycardias and presents a potentially novel benefit of septal pacing.

Prolonged Signal-Averaged P-Wave Duration as an Intermediate Phenotype for Familial Atrial Fibrillation

This study sought to perform a genome-wide linkage analysis in a large atrial fibrillation (AF) kindred using AF and abnormally prolonged signal-averaged (SA) P-wave duration as the phenotype. Although inherited forms of AF exist, phenotypic complexity has limited efforts to ascertain mutation carriers and thus identify causal genes. The identification of intermediate or endophenotypes may accelerate this effort. A genome-wide linkage analysis was performed in a 4-generation AF kindred of 27 individuals, 8 with AF documented by electrocardiogram. The analysis was performed using AF as the phenotype, and repeated using an abnormally prolonged SA P-wave duration as the phenotype. Linkage analysis and fine mapping generated a maximum multipoint logarithm of the odds (LOD) score of 3.0 at chromosome 5p15 between markers D5S406 and D5S635. Importantly, 8 heterozygous carriers had a prolonged SA P-wave (203 +/- 21 ms) compared with 17 noncarriers (116 +/- 12 ms, p < 0.00001). Using prolonged SA P-wave (conventionally defined as >155 ms) as an endophenotype, a maximum LOD score of 3.6 was obtained in the same region of chromosome 5p15, a span of 5.75 centi-Morgans. In a large AF kindred, we have identified a novel AF locus on chromosome 5p15 and shown that affected individuals with AF and mutation carriers can be identified by a prolonged SA P-wave duration. Importantly, identification of an endophenotype in this kindred not only aided ascertainment of additional family members but also increased the LOD score, providing increased support for linkage at this locus. Identification of the causal gene, mapped to chromosome 5p15, will advance our understanding of the molecular basis of AF.

Signal-averaged P wave duration and the long-term risk of permanent atrial fibrillation

Objective. To assess the long-term risk of developing permanent AF in relation to the signal-averaged P wave duration (SAPWD) and clinical and echocardiographic characteristics. Design. In an observational study design we studied 131 patients with earlier ECG-documented AF and successfully restored sinus rhythm attending a long-term, follow-up visit at hospital or at home. Established permanent AF was examined in relation to primary clinical, echocardiographic, and electrophysiological parameters. Results. Only prolonged SAPWD (p =0.006) was associated with an increased risk of development of permanent AF. The risk of permanent AF after 3 years follow-up was 0.72 with an SAPWD equal to 180 ms versus 0.39 with a normal SAPWD (130 ms). We found no prognostic effect of age, gender, dilated left atrium, long duration of AF history, or long duration of the most recent episode of AF. Co-existing hypertension reduced the risk of permanent AF; this could be explained by concomitant treatment with angiotensin-converting-enzyme-inhibitors. Conclusion. Prolonged SAPWD (a marker of atrial remodelling) appears to be a risk factor for long-term development of permanent AF.

Filtered signal-averaged P-wave duration during pneumoperitoneum in patients undergoing laparoscopic cholecystectomy: A reflection of pathophysiological cardiac changes

Induction of pneumoperitoneum (PP) may lead to adverse cardiac functions secondary to changes such as decreased venous return and hypercarbia. The assessment of cardiac electrical activity by signal averaging may reflect various hemodynamic derangements and serve as a prognostic marker for arrhythmias. The aim of the study is to examine characteristic electrocardiographic changes that may occur during PP, by using signal-averaged P-wave analysis. Twenty healthy (ASA I and II) patients were enrolled in a prospective paired control study, and underwent elective laparoscopic cholecystectomy. A standard ECG together with computerized filtered signal-averaged P-wave duration measurement (leads X, Y, Z) were carried out during awareness, under anesthesia before and during PP, and after CO(2) evacuation. Depth of anesthesia was controlled by bi-spectral index (BIS). An increased duration of P-wave was observed during PP in comparison to the anesthesia phase before PP (111 versus 115 ms, t-test and Wilcoxon signed rank test). A significant increase was also detected in the maximal value of P-wave duration between these phases of the operation. The difference in the number of patients in whom the duration increased by at least 5 ms was also found to be significant. Primarily, a decreased P-wave duration was expected, due to cardiac autonomic sympathetic predominance during PP. Its prolongation during PP may reflect some cardiac pathophysiological (structural and functional) changes, including influence on cardiac ion channels during depolarization. Usually, clinical consequences related to laparoscopic cholecystectomy are absent, but clinical awareness should be maintained for cardiac diseased patients undergoing prolonged laparoscopic procedures.

Risk Factors for Atrial Fibrillation in Adult Patients in Long-Term Observation Following Surgical Closure of Atrial Septal Defect Type II

The aim of the study was to find the factors predictive for paroxysmal atrial fibrillation (AF) following surgical correction of atrial septal defect type II (ASD t.II). 93 patients, who underwent isolated surgical closure of ASD t.II between 1990 and 2001 were included. Follow-up studies were performed 2 - 11 years after surgery. Patients were divided into two groups according to the presence of AF before and after surgery. Group AF (+) consisted of 29 and group AF (-) of 64 patients. All patients underwent echocardiography, electrocardiogram (ECG) at rest, and signal-averaged P-wave duration (PWD) in signal-averaged ECG. The following parameters were assessed in echocardiography: pulmonary artery systolic pressure, left and right atrial dimensions, right ventricular dimension, tricuspid and mitral regurgitation. Paroxysmal AF was observed in 27 patients before surgery and in 29 after surgery. Analyzing all potential risk factors we proved that PWD may independently predict occurrence of postoperative AF. PWD may independently predict postoperative AF in long-term follow-up after surgical correction of ASD t.II.

Atrial Fibrillation Recurrence: The Roles of Hypertension, Duration of Atrial Fibrillation Disease, and Prolonged Signal-Averaged P Wave Duration

Objective - To assess the risk of atrial fibrillation (AF) recurrence requiring hospitalisation or its transition to long-lasting AF in patients with earlier or present AF from the clinical characteristics, the duration of AF-disease, and the signal-averaged P wave duration (SAPWD). Design -We studied 111 consecutive patients (40 women; median age 65 years, range 30-85 years) with earlier or present AF. The SAPWD was measured on inclusion; the follow-up median follow-up time was 184 days (range 171-437). Endpoints were hospitalisation due to recurrent AF or transition to AF lasting longer than two days. Results -During follow-up 5 patients died, 33 patients were hospitalised with AF, and 9 patients developed long-lasting AF. Multiple logistic regression analysis showed three risk factors of interest: history of hypertension, OR=3.67 (95% CI 1.61 to 8.37), duration of AF disease longer than two years, OR=3.22 (95% CI 1.31 to 7.86), and non-significantly prolonged SAPWD above 140 ms, OR=1.87 (95% CI 0.60 to 5.82). The probability of relapse in patients without risk factors was 9%, with one risk factor 16-27%, with two risk factors 37-54%, and with three risk factors 74% (p=0.0005). Conclusions -Hypertension and long history of AF disease were associated with an increased risk of AF-relapse.

The signal-averaged P-wave duration is longer in hypertensive patients with history of paroxysmal atrial fibrillation as compared to those without

Background Onset of atrial fibrillation in hypertensive patients is usually associated with a high occurrence of cardiovascular complications. Therefore, it is important to assess non-invasively the risk of developing paroxysmal atrial fibrillation (PAF) in hypertensive patients during sinus rhythm. This study was undertaken to determine if hypertensive patients with history of PAF could be identified while in sinus rhythm by measurement of signal-averaged ECG P-wave duration. Methods Signal-averaged electrocardiography (SAECG) P-wave recording was performed in 44 hypertensive patients (30 men and 14 women; mean age 60±11 years, group A) who had a history of paroxysmal AF and in 50 hypertensive patients without history of AF (33 men and 17 women; mean age 57±12, group B). All patients were also evaluated by using echocardiography to measure left ventricular ejection fraction (LVEF) and left atrial diameter (LAD). Results SAECG P-wave duration was found to be significantly higher in group A than in group B (146±14 ms vs. 128±11 ms, p<0.001). Left atrial diameter was not significantly different (40.1±3.4 mm vs. 39.3±3.0 mm, p>0.05), whereas LVEF was significantly lower in group A than group B (63±5% vs. 67±4%, p=0.03). There was a correlation between SAECG P-wave duration and age ( r=0.32, p<0.05). In univariate analysis, SAECG P-wave duration and LVEF were significant predictors of PAF, but only SAECG P-wave duration remained a significant independent predictor of PAF in multivariate analysis. Conclusion The results of this study indicate that hypertensive patients with history of PAF can be detected while in sinus rhythm by signal-averaged ECG P-wave duration.

Angiotensin-converting enzyme inhibitors as adjunctive therapy in patients with persistent atrial fibrillation

Objectives The purpose of the current study was to assess the effect of angiotensin-converting enzyme inhibitor (ACEI) therapy in facilitating cardioversion from persistent atrial fibrillation (AF) and maintaining sinus rhythm. Background Pharmacologic therapy and electrical cardioversion for AF are often unsuccessful in maintaining long-term sinus rhythm. Methods The current study, a 1-year, prospective follow-up, comprised 47 patients with persistent AF undergoing electrical cardioversion. Patients receiving ACEI were compared with those receiving other medications. The study end point was the number of defibrillation attempts required for atrial defibrillation and the number of hospital admissions. A secondary end point was change in signal-averaged P-wave duration (SAPD) 1 year after successful electrical cardioversion. Results Of those admitted and requiring electrical defibrillation, the number of defibrillation attempts required for successful cardioversion was significantly less in the ACEI group ( P < .001). The incidence rate ratio for admissions comparing recipients of ACEI with others was 0.14 ( P = .03). Patients receiving ACEI therapy had significantly lower SAPD at 1 year when compared with the no-ACEI group (135 ms ± 3 vs 150 ms ± 2, P = .002). Conclusions The use of long-term ACEI therapy facilitated electrical defibrillation in patients with persistent AF. ACEI therapy also reduced SAPD, suggesting amelioration of the arrhythmogenic substrate. Furthermore, we confirmed that SAPD is prolonged in patients with persistent AF.

Prolonged signal‐averaged P wave duration after elective cardioversion increases the risk of recurrent atrial fibrillation

Objective—To assess the risk of atrial fibrillation (AF) recurrence after elective cardioversion of AF in relation to the signal‐averaged P wave duration (SAPWD), clinical characteristics of the patient, and the duration of the AF disease.Design—We studied 131 consecutive patients (88 men, 43 women), median age 67 years (range 29–87 years), after elective cardioversion of AF into sinus rhythm. The SAPWD was measured on inclusion, and the follow‐up period was 1 month. Recurrent AF within the first month after cardioversion was regarded as endpoint.Results—AF recurred in 73 patients (56%). Multiple logistic regression analysis showed that prolonged SAPWD above 160 ms was the only significant risk factor for recurrent AF, OR=2.22 (95% CI 1.07–4.60), p=0.03. There was no significant effect of age, diagnosed hypertension, diagnosed congestive heart failure, dilated left atrium, or long duration of AF on the risk of AF relapse.Conclusion—Prolonged SAPWD above 160 ms is a risk factor for recurrent AF after elective cardioversion of persistent AF.

Prolonged signal-averaged P wave duration as a prognostic marker for morbidity and mortality in patients with congestive heart failure

Objective --To evaluate the prognostic roles of prolonged signal-averaged P wave duration (SAPWD), raised levels of natriuretic peptides, and clinical characteristics in patients with stable congestive heart failure (CHF). Design --The SAPWD was assessed from a signal-averaged electrocardiogram (SAECG), and the plasma levels of N-terminal pro-atrial natriuretic peptide (Nt-proANP) and N-terminal pro-brain natriuretic peptide (Nt-proBNP) were measured in 43 consecutive patients with stable CHF without prior supraventricular arrhythmia. Echocardiographic and clinical data were also recorded. Time to death, hospitalization due to deteriorated CHF, or ECG-documented atrial fibrillation (AF) was recorded over a 438-day median follow-up. Results --During follow-up, 17 patients met an endpoint defined as death, AF, or hospitalization due to deteriorated CHF. Proportional hazard regression including the variables high age, prolonged SAPWD, raised levels of Nt-proANP and Nt-proBNP, and low ejection fraction (EF) showed that only prolonged SAPWD S 149 r ms was associated with an increased risk of meeting an early endpoint; the hazard ratio 3.94 with 95% confidence interval 1.50-10.42; p r = r 0.006. Conclusion --Prolonged SAPWD appears to predict early death, AF development, or hospitalization due to deterioration of CHF in patients with stable CHF.