Effect of left atrial size and function on P-wave dispersion: a study in patients with paroxysmal atrial fibrillation

Cardiovascular Disease and Inpatient Complications in Turner Syndrome: A Propensity Score Analysis

BACKGROUND

Turner syndrome is a genetic disorder that occurs in female individuals and is characterized by the absence of 1 of the X chromosomes. This study examined the risk of cardiovascular disease and inpatient clinical outcomes in patients with Turner syndrome.

METHODS

Data were extracted from the Nationwide Inpatient Sample 2016 database. Propensity score analysis was used to match women with Turner syndrome and women without Turner syndrome admitted to a hospital in the same year to evaluate the risk of cardiovascular disease and inpatient clinical outcomes in patients with Turner syndrome.

RESULTS

After 1:1 matching, 710 women with Turner syndrome and 710 women without Turner syndrome were included in the final analysis. Compared with women without Turner syndrome, women with Turner syndrome were more likely to have a bicuspid aortic valve (9.4% vs 0.01%; P < .01), coarctation of the aorta (5.8% vs 0.3%; P < .01), atrial septal defect (6.1% vs 0.8%; P < .01), and patent ductus arteriosus (4.6% vs 0.6%; P < .01). Patients with Turner syndrome were more likely to have an aortic aneurysm (odds ratio [OR], 2.46 [95% CI, 1.02-5.98]; P = .046), ischemic heart disease (OR, 1.66 [95% CI, 1.10-2.5]; P = .02), heart failure (OR, 3.15 [95% CI, 1.99-4.99]; P < .01), and atrial fibrillation or flutter (OR, 2.48 [95% CI, 1.42-4.34]; P < .01). Patients with Turner syndrome were more likely to have pulmonary arterial hypertension (OR, 2.12 [95% CI, 1.08-4.14]; P = .03) and acute kidney injury (OR, 1.60 [95% CI, 1.06-2.42]; P = .03) and to require mechanical ventilation (OR, 1.66 [95% CI, 1.04-2.68]; P = .04).

CONCLUSION

Turner syndrome is associated with an increased rate of cardiovascular disease and inpatient complications. These findings suggest that patients with Turner syndrome should be screened and monitored closely for cardiovascular disease and inpatient complications.

Assessment of P Wave Indices in Healthy Standardbred Horses

P wave indices are used as non-invasive electrocardiographic markers of atrial remodelling in humans. Few studies have investigated their use in animals. The aim of this study was to measure P wave duration and P wave dispersion (Pd) in healthy standardbred horses and investigate variables that might influence these measurements. A 12-lead electrocardiogram was recorded at rest and P wave indices were calculated in 53 horses. A general linear model was used to investigate the main effects: age, bodyweight, sex, resting heart rate, presence of a murmur, exercise status and the number of years raced. There were significant associations with exercise status for both the maximum P wave duration and Pd, with both values being increased in strenuously exercising versus non-active horses. Furthermore, a significant moderate positive correlation was identified between the duration of exercise (number of years raced) and both Pmax and Pd. No other significant associations were identified. These findings are similar to those reported in elite human athletes versus sedentary individuals. The increases in these P wave indices most likely occur due to prolongation and heterogeneity in atrial conduction time, which are associated with structural and electrical remodelling, and may explain the increased risk of atrial fibrillation in athletic horses.

Markers of Atrial Cardiopathy in Severe Embolic Strokes of Undetermined Source

Background and Purpose

The current definition of embolic strokes of undetermined source (ESUS) seems to be too broad, including strokes due to heterogeneous mechanisms, such as atrial cardiopathy and other occult cardiac conditions, aortic arch plaques, and non-stenosing atherosclerosis, that can be differently associated with clinical stroke severity at the time of presentation. The aim of our study was to assess the possible association between neurological deficit severity and presence of markers of atrial cardiopathy in ESUS.

Methods

We retrospectively reviewed the medical records of a cohort of 226 ESUS patients (105 M, 121 F), that were divided into two groups according to the severity of neurological deficit (99 mild strokes with NIHSS ≤ 5 and 127 severe strokes with NIHSS >5). The following indices of atrial cardiopathy were evaluated: P wave dispersion, P wave max, P wave min, P wave mean, P wave index, P wave axis, left atrial size.

Results

Patients with severe ESUS were significantly older (74 ± 12 vs. 67 ± 14 years, P < 0.001) and female sex was prevalent (67 vs. 36%, P > 0.001); they had higher values of P-wave-dispersion (51 ± 14 vs. 46 ± 13, P = 0.01), P-wave-max (131 ± 20 vs. 125 ± 15 ms, P = 0.01), P-wave-index (16 ± 5 vs. 15 ± 5 ms, P = 0.01), left atrial size (20 ± 6 vs. 18 ± 4 cm², P = 0.01), left atrial volume index (31 ± 14 vs. 27 ± 11 ml/m², P = 0.04), in comparison with mild ESUS. An abnormal P wave axis was detected more frequently in severe ESUS (21 vs. 9%, P = 0.01). Furthermore, multivariate logistic regression showed that age (OR = 1.21 for each 5-year increase, 95% CI 1.09–1.35), sex (OR = 3.24 for female sex, 95% CI 1.82–5.76) and PWD (OR = 1.32 for each 10-ms increase, 95% CI 1.07–1.64) were the best subset of associated variables for severe ESUS.

Conclusions

Our findings shed light on specific clinical characteristics of severe ESUS including the presence of atrial cardiopathy that could play a pathogenic role in this subgroup of patients. Searching for atrial fibrillation in these patients is especially important to perform the most appropriate therapy.

Clinical value of the combined use of P-wave dispersion and troponin values to predict atrial fibrillation recurrence in patients with paroxysmal atrial fibrillation

INTRODUCTION

P-wave dispersion (PWD) and cardiac troponin levels are independently associated with the recurrence of atrial fibrillation (AF) in patients with paroxysmal AF (PAF). We investigated the clinical usefulness of combining PWD and cardiac troponin I to predict AF recurrence in patients presenting to the emergency department with PAF.

METHODS

This study included 65 patients with PAF who were divided into three groups according to baseline troponin I and PWD values (group 1, troponin I<0.11 ng/dl and PWD<44.5 ms; group II, troponin I<0.11 ng/dl and PWD≥44.5 ms, or troponin I≥0.11 ng/dl and PWD<44.5 ms; group III, troponin I≥0.11 ng/dl and PWD≥44.5 ms).

RESULTS

The AF recurrence rate was significantly higher in group III than in groups I and II. Multivariate analysis revealed that the troponin I and PWD values in group III (odds ratio: 7.236, 95% confidence interval: 1.879-27.861, p=0.004) were independent predictors of AF recurrence.

CONCLUSIONS

The combined use of PWD and basal troponin I levels is a better predictor of AF recurrence than either value alone.

Effect of ranolazine on Tp-e interval, Tp-e/QTc, and P-wave dispersion in patients with stable coronary artery disease

INTRODUCTION

Ranolazine is an antianginal drug and also exhibits antiarrhythmic effect by affecting action potential time, refractory period, and repolarization reserve. We evaluated the effect of ranolazine therapy on myocardial repolarization parameters (Tp-e, QT, QTc intervals, Tp-e/QT, and Tp-e/QTc ratios), index of cardiac electrophysiological balance (iCEB) (QT/QRS, QTc/QRS) and P-wave dispersion (PWD) in patients with stable coronary artery disease (CAD).

METHODS

This study included 175 patients, aged between 35 and 90 years who were followed with stable CAD for at least 3 months. Ninety patients had been receiving ranolazine for at least 1 month, and 85 patients had never received ranolazine. All patients' basic demographic data, risk factors, medications, and echocardiographic parameters recorded. Myocardial repolarization parameters, P-wave times, and PWD were analyzed from 12 lead electrodes.

RESULTS

There was no variation between the groups in terms of basic demographic parameters and CAD risk factors. Tp-e interval (87.3 ± 14.4 vs. 90.8 ± 12.4 msn, P < .001), Tp-e/QT (0.22 ± 0.04 vs. 0.23 ± 0.03; P = .03), Tp-e/QTc (0.21 ± 0.04 vs. 0.22 ± 0.04 P = .001), and PWD (39.2 ± 13.7 vs. 43.5 ± 12.9 P = .028) were significantly lower in the ranolazine group. But iCEB was similar in both groups. In multivariate analysis after adjusted confounding factors such as age and BMI, Tp-e/QTc ratio, QTc, Pmax, and PWD were found significantly in ranolazine group again.

CONCLUSION

Tp-e/QTc ratio, QTc, Pmax, and PWD were significantly lower in stable CAD patients under ranolazine therapy. In stable CAD patients, the prognostic significance of ranolazine for arrhythmic events requires further evaluation of these parameters through long-term follow-up and large-scale prospective studies.

Clinical value of the combined use of P-wave dispersion and troponin values to predict atrial fibrillation recurrence in patients with paroxysmal atrial fibrillation

INTRODUCTION

P-wave dispersion (PWD) and cardiac troponin levels are independently associated with the recurrence of atrial fibrillation (AF) in patients with paroxysmal AF (PAF). We investigated the clinical usefulness of combining PWD and cardiac troponin I to predict AF recurrence in patients presenting to the emergency department with PAF.

METHODS

This study included 65 patients with PAF who were divided into three groups according to baseline troponin I and PWD values (group 1, troponin I<0.11 ng/dl and PWD<44.5 ms; group II, troponin I<0.11 ng/dl and PWD≥44.5 ms, or troponin I≥0.11 ng/dl and PWD<44.5 ms; group III, troponin I≥0.11 ng/dl and PWD≥44.5 ms).

RESULTS

The AF recurrence rate was significantly higher in group III than in groups I and II. Multivariate analysis revealed that the troponin I and PWD values in group III (odds ratio: 7.236, 95% confidence interval: 1.879-27.861, p=0.004) were independent predictors of AF recurrence.

CONCLUSIONS

The combined use of PWD and basal troponin I levels is a better predictor of AF recurrence than either value alone.

Chromosomal abnormalities and atrial fibrillation and ischemic stroke incidence: a nationwide population-based study

There is a paucity of information as to whether chromosomal abnormalities, including Down Syndrome, Turner Syndrome, and Klinefelter Syndrome, have an association with atrial fibrillation (AF) and ischemic stroke development. Data from 3660 patients with Down Syndrome, 2408 with Turner Syndrome, and 851 with Klinefelter Syndrome without a history of AF and ischemic stroke were collected from the Korean National Health Insurance Service (2007–2014). These patients were followed-up for new-onset AF and ischemic stroke. Age- and sex-matched control subjects (at a ratio of 1:10) were selected and compared with the patients with chromosomal abnormalities. Down Syndrome patients showed a higher incidence of AF and ischemic stroke than controls. Turner Syndrome and Klinefelter Syndrome patients showed a higher incidence of AF than did the control group, but not of stroke. Multivariate Cox regression analysis revealed that three chromosomal abnormalities were independent risk factors for AF, and Down Syndrome was independently associated with the risk of stroke. In conclusion, Down Syndrome, Turner Syndrome, and Klinefelter Syndrome showed an increased risk of AF. Down Syndrome patients only showed an increased risk of stroke. Therefore, AF surveillance and active stroke prevention would be beneficial in patients with these chromosomal abnormalities.

P wave dispersion in patients with erectile dysfunction

Background and aims

P wave dispersion (PWD) has been reported to be a non-invasive electrocardiographic predictor for atrial fibrillation. The aim of this study is to evaluate PWD between men with erectile dysfunction (ED) and healthy controls in order to investigate whether PWD was prolonged in patients with ED and related to severity of the disease.

Methods

This study included a total of 72 men (42 patients with ED and 30 healthy controls). Demographic data and clinical features were recorded on admission. An electrocardiographic evaluation was obtained to measure PWD values for both patients and controls.

Results

Maximum P wave duration was 108.5 ± 4.7 and 108.3 ± 4.3 in ED group and control group, respectively (p = 0.748). Minumum P wave duration was significantly higher in the control group than in the ED group. PWD was 48.1 ± 5.9 in the ED group. As a result, PWD was prolonged in patients with ED (48.1 ± 5.9 vs. 38.0 ± 3.9, p < 0.05). A significant negative correlation was observed between IIEF score and PWD values (p < 0.05, r = −0.662).

Conclusions

Patients with ED exhibited prolonged PWD values compared with normal controls. In addition, PWD was found to be associated with severity of the disease.

P-wave and QT dispersion in hypertensive disorders of pregnancy

Aim: To compare P-wave and QT dispersion values in hypertensive disorders of pregnancy and controls and also in preeclampsia, chronic hypertension, and gestational hypertension separately.Material and methods: We included 140 hypertensive pregnants and 110 healthy age-matched pregnants in this study. The hypertensive pregnants were divided into three subgroups: preeclampsia (n = 43), chronic hypertension (n = 51), and gestational hypertension (n = 46). P-wave and QT dispersion values were compared between groups.Results: Hypertensive pregnants had higher P-wave (41.74 ± 5.51 vs. 37.73 ± 5.62, p < .001) and QTc dispersion (45.44 ± 7.62 vs. 39.77 ± 8.34, p < .001) values. In subgroup analysis, P-wave dispersion and QTc dispersion were different between preeclamptic, chronic hypertensive, and gestational hypertensive patients. Also, they were significantly higher in chronic hypertension as compared to gestational hypertension and they were higher in preeclampsia than in gestational hypertension. No difference was found according to these parameters between preeclampsia and chronic hypertension. In correlation analysis, both P-wave dispersion and QTc dispersion were positively correlated with systolic (r = 0.409, p < .001 and r = 0.306, p < .001) and diastolic blood pressure (r = 0.390, p < .001 and r = 0.287, p < .001) which are main clinical determinants of hypertensive disorders.Conclusion: In clinical practice, chronic hypertensive pregnants are generally followed up in their future life for cardiovascular disorders. Also, we recommend that we must inform and follow preeclamptic patients for future cardiovascular diseases.

Electrocardiogram (ECG) for the Prediction of Incident Atrial Fibrillation: An Overview

Electrocardiograms (ECGs) have been employed to medically evaluate participants in population-based studies, and ECG-derived predictors have been reported for incident atrial fibrillation (AF). Here, we reviewed the status of ECG in predicting new-onset AF. We surveyed population-based studies and revealed ECG variables to be risk factors for incident AF. When available, the predictive values of each ECG risk marker were calculated. Both the atrium-related and ventricle-related ECG variables were risk factors for incident AF, with significant hazard risks (HRs) even after multivariate adjustments. The risk factors included P-wave indices (maximum P-wave duration, its dispersion or variation and P-wave morphology) and premature atrial contractions (PACs) or runs. In addition, left ventricular hypertrophy (LVH), ST-T abnormalities, intraventricular conduction delay, QTc interval and premature ventricular contractions (PVCs) or runs were a risk of incident AF. An HR of greater than 2.0 was observed in the upper 5th percentile of the P-wave durations, P-wave durations greater than 130 ms, P-wave morpholyg, PACs (PVCs) or runs, LVH, QTc and left anterior fascicular blocks. The sensitivity , specificity and the positive and negative predictive values were 3.6-53.8%, 61.7-97.9%, 2.9-61.7% and 77.4-97.7%, respectively. ECG variables are risk factors for incident AF. The correlation between the ECG-derived AF predictors, especially P-wave indices, and underlying diseases and the effects of the reversal of the ECG-derived predictors on incident AF by treatment of comorbidities require further study.

Postoperative hyperglycemia and atrial fibrillation after coronary artery bypass graft surgery

BACKGROUND

Postoperative atrial fibrillation (AF) is a common complication following coronary artery bypass grafting (CABG). We investigated the risk factors for postoperative AF and analyzed the relationship between blood sugar concentration (BS) and AF after CABG.

METHODS AND RESULTS

A total of 199 consecutive patients who underwent isolated CABG were retrospectively examined and classified according to the presence (n=95) or absence (n=104) of postoperative AF. On univariate analysis mean postoperative BS (P<0.001), postoperative drainage volume (P<0.001), age (P=0.034), presence of diabetes mellitus (DM; P=0.004), and postoperative estimated glomerular filtration rate (P=0.032) were significant risk factors for postoperative AF. On multivariate analysis mean postoperative BS (OR, 1.041; 95% CI: 1.008-1.079; P<0.001), postoperative drainage volume (OR, 1.003; 95% CI: 1.001-1.006; P=0.001), and age (OR, 1.040; 95% CI: 1.002-1.083; P=0.041) were significant risk factors for postoperative AF. Postoperative AF often occurred in patients with high postoperative BS, irrespective of DM. The BS cut-off that predicted postoperative AF occurrence was 180 mg/dl. A strong positive correlation existed between the time of the maximum postoperative BS and AF onset time (ρ=0.746).

CONCLUSIONS

Mean postoperative BS and postoperative drainage volume are risk factors for AF after CABG. AF was strongly associated with maximum postoperative BS. Intensive glycemic control could reduce AF occurrence after CABG.

Effects of lying position on P-wave dispersion in patients with heart failure

OBJECTIVE

It was the aim of this study to investigate the effects of the right lateral decubitus, left lateral decubitus and supine lying position on P-wave dispersion (PWD) in patients with heart failure (HF).

SUBJECTS AND METHODS

Seventeen patients with HF whose ejection fraction was <35% were included in the study. Right lateral decubitus, left lateral decubitus and supine electrocardiogram (ECG) recordings were obtained. The recordings for each of the three positions were taken after the patients had maintained each position for 30 min to ensure a stabilized hemodynamic position. For the baseline recording, in supine position, there was no 30-min waiting period before the ECG.

RESULTS

After the right lateral decubitus position, there was a statistically significant reduction in the longest P-wave duration (100.0 ± 14.5 and 84.7 ± 16.2 ms; p = 0.001) and a significant decrease in PWD (41.7 ± 8.0 and 24.1 ± 7.1 ms; p < 0.0001). After the left lateral decubitus position, there was no significant change between the baseline PWD values (41.7 ± 8.0 and 40.2 ± 9.7 ms; p = 0.606). After the supine position, there was no significant change between the baseline PWD values (41.7 ± 8.0 and 39.7 ± 9.4 ms; p = 0.427).

CONCLUSION

Our study revealed that patients' PWDs and maximum P-wave durations were lower in the right lateral decubitus lying position than in other positions. The clinical implication of this study needs to be further explored.

P-wave dispersion for predicting paroxysmal atrial fibrillation in acute ischemic stroke

BACKGROUND

Detection of paroxysmal atrial fibrillation (PAF) in acute ischemic stroke patients poses diagnostic challenge. The aim of this study was to predict the presence of PAF by means of 12-lead ECG in patients with acute ischemic stroke. Our hypothesis was that P-wave dispersion (P(d)) might be a useful marker in predicting PAF in patients with acute ischemic stroke.

METHODS

12-lead resting ECGs, 24-hour Holter recordings and echocardiograms of 400 patients were analyzed retrospectively. PAF was detected in 40 patients on 24-hour Holter monitoring. Forty out of 360 age and gender matched patients without PAF were randomly chosen and assigned as the control group. Demographics, P-wave characteristics and echocardiographic findings of the patients with and without PAF were compared.

RESULTS

Maximum P-wave duration (p=0.002), P(d) (p<0.001) and left atrium diameter (p=0.04) were significantly higher in patients with PAF when compared to patients without PAF. However, in binary logistic regression analysis P(d) was the only independent predictor of PAF. The cut-off value of P(d) for the detection of PAF was 57.5 milliseconds (msc). Area under the curve was 0.80 (p<0.001). On a single 12-lead ECG, a value higher than 57.5 msc predicted the presence of PAF with a sensitivity of 80% and a specificity of 73%.

CONCLUSION

P(d) on a single 12-lead ECG obtained within 24 hours of an acute ischemic stroke might help to predict PAF and reduce the risk of recurrent strokes.

Increased p wave dispersion in elite athletes

BACKGROUND

Few studies have been performed on P wave indices in athletes. The aim of this study was to determine the behaviour of maximum P wave duration (Pmax), minimum P wave duration (Pmin) and P wave dispersion (PWD) in young high performance athletes, as well as the relationship of PWD with training history, heart rate (HR) and echocardiographic parameters.

METHODS

We performed a cross-sectional observational study in 38 athletes of high performance in sports: water polo, distance running and weight lifting compared with 34 sedentary controls.

RESULTS

The average age in both groups was 20.6 years. Note that PWD was increased in athletes (57 ± 14 ms vs. 40 ± 12 ms, p <0.001) while Pmin was significantly lower (57 ± 13 ms vs. 72 ± 13 ms, p <0.001), and there was no difference when comparing Pmax (114 ± 9 ms vs. 117 ± 14 ms, p> 0.05). The correlation between the duration of training (r = 0.511) and resting HR (r = 0.461) with PWD was significant (p <0.01).

CONCLUSIONS

PWD is increased in young athletes of high performance and was positively correlated with duration of training and baseline HR. The increase in PWD was secondary to a significant decrease in Pmin.

P-wave dispersion and heart rate variability in children with mitral valve prolapse

Previous studies have reported that patients with mitral valve prolapse (MVP) may display autonomic dysfunction. Measurement of heart rate variability (HRV) and P-wave dispersion (PWD) may provide insights into the functional state of the autonomic nervous system. Heart rate variability (HRV) has been used as a noninvasive marker of autonomic activity. However, to the authors' knowledge, PWD has not been studied in the context of MVP. This study aimed to examine HRV and PWD in patients with MVP and to determine whether differences exist between symptomatic and asymptomatic patients. The study population consisted of 54 healthy children (17 boys and 37 girls) ages 6-18 years and 76 patients with MVP (20 boys and 56 girls) ages 6-18 years. The duration and dispersion of the P-wave were measured by surface 12-lead electrocardiograms (ECGs). Heart rate variability was quantified using both time-domain and frequency-domain analyses of Holter ECGs. The minimum duration of the P-wave was significantly lower in the MVP patients (42.4 ± 10.0 ms) than in the control subjects (54.4 ± 12.8 ms) (p < 0.01), and the PWD was significantly increased in the MVP group (42.7 ± 10.8 ms) compared with the control subjects (31.8 ± 10.9 ms) (p < 0.01). However, no significant differences were found between the symptomatic and asymptomatic patients. In addition, the HRV parameters were not statistically different between the two groups. In conclusion, although HRV parameters were not significantly different between the MVP and control groups, the findings show that PWD was increased for the children with MVP. However, no relationship could be established between PWD and clinical symptoms.

P-wave dispersion in endogenous and exogenous subclinical hyperthyroidism

BACKGROUND

The aim of this study was to measure maximum P wave duration (Pmax) and P wave dispersion (PWD), which can be indicators for the risk of paroxysmal atrial fibrillation when increased, and to reveal their relationship with thyroid hormone levels in patients with endogenous and exogenous subclinical hyperthyroidism.

METHODS

Seventy-one patients with sublinical thyrotoxicosis (34 endogenous, 37 exogenous) and 69 healthy individuals were enrolled in the study. Pmax and minimum P wave duration (Pmin) on electrocardiogram recordings were measured and PWD was calculated as Pmax-Pmin.

RESULTS

Pmax (p<0.001) and PWD (p<0.001) values were significantly higher in patients with endogenous subclinical hyperthyroidism compared with the control group. Pmax (p<0.001) and PWD (p<0.001) values were significantly higher in patients with exogenous subclinical thyrotoxicosis compared with the control group. Pmax (p=0.710) and PWD (p=0.127) were not significantly different in patients with endogenous subclinical hyperthyroidism compared with exogenous subclinical hyperthyroid patients. Pmax and PWD negatively associated with TSH in endogenous and exogenous subclinical hyperthyroidism.

CONCLUSION

In the present study, we observed that Pmax and PWD were longer in patients with endogenous and exogenous subclinical hyperthyroidism. Lack of a difference in Pmax and PWD between patients with endogenous and exogenous subclinical hyperthyroidism seems to support the idea that hormone levels rather than the etiology of thyrotoxicosis affect the heart.

The effect of rapid blood pressure control on P-wave dispersion in hypertensive urgency

INTRODUCTION

A sharp increase in blood pressure, increase in atrial pressure and atrial strain, left ventricular diastolic dysfunction, and left ventricular hypertrophy (LVH) lead to heterogeneity and instability in atrial conduction. The resulting physiopathological situation may elevate maximum Pwave duration (P(max)) and P-wave dispersion (PWD) in electrocardiography. The objective of our study was to explore the effect of the sudden change in atrial hemodynamics on P(max) and PWD, which may indicate the risk of atrial fibrillation (AF) development in hypertensive urgency.

METHODS

The study included patients diagnosed as hypertensive urgency (systolic blood pressure > or =180 mmHg, diastolic blood pressure > or =110 mmHg). Nitroprusside was started at a dose of 0.2 microg/kg/min, and the ensuing dose was arranged according to blood pressure. Echocardiography and electrocardiography were used to noninvasively measure changes in diastolic function and PWD and P(max), respectively.

RESULTS

The study enrolled 102 patients (mean age 57.9+/-11.6 years; 32 [31.4%] males, and 70 [68.6%] females). P(max) decreased from 99.9+/-11.1 msec (95% confidence intervals [CI] 97.7, 102) to 88.5+/-9.3 msec (95% CI 86.6, 90.3) (P<0.001), while PWD decreased from 60.1+/-7.4 msec (95% CI 58.7, 61.6) to 43.9+/-6.7 msec (95% CI 42.5, 45.2) (P<0.001). In addition, most patients had LVH and diastolic dysfunction. After nitroprusside treatment improvements in indicators of diastolic functions such as E/A ratio, deceleration time, and isovolumetric relaxation time were observed.

CONCLUSION

The change observed in P(max) and PWD in hypertensive urgency may be associated with the rapid change in blood pressure and atrial strain, sympathetic nervous system activation, relative myocardial ischemia, and left ventricular diastolic dysfunction. Rapid regulation of blood pressure with nitroprusside brought about a marked decrease in P(max) and PWD in our patients. This improvement was interpreted as atrial conduction acquiring a stable and homogeneous character, which may reduce the risk of AF development in hypertensive urgency.

Comparison of the effects of quinapril and irbesartan on P-wave dispersion in hypertensive patients

INTRODUCTION

P-wave dispersion (PWD) has been shown to be a non-invasive electrocardiographic predictor for development of atrial fibrillation (AF). Thus, it may be possible to attenuate AF risk through improvement of PWD. In this study, we compared the effects of an angiotensin-converting enzyme (ACE) inhibitor, quinapril, and an angiotensin receptor blocker (ARB), irbesartan, on PWD.

METHODS

A total of 38 newly diagnosed hypertensive patients were enrolled in the study. The patients were randomly assigned to receive treatment with either irbesartan (150-300 mg) or quinapril (20-40 mg). P-wave durations and PWD were measured at baseline and after 6 and 12 months of treatment. Echocardiographic examinations were performed at baseline and after 12 months of treatment.

RESULTS

Both drugs significantly reduced blood pressure to a similar degree (P<0.001). Deceleration time (both P<0.001) and isovolumetric relaxation time (both P=0.007) were also significantly reduced, whereas there was no significant change in the early diastolic flow/atrial contraction signal ratio. Both irbesartan and quinapril significantly decreased maximum P-wave duration (Pmax) (P<0.001 and P=0.002, respectively) and PWD (from 68.0+/-22.1 to 41.0+/-25.1 msec for irbesartan, and from 70.5+/-20.4 to 46.6+/-13.3 msec for quinapril; both P<0.001). Baseline and follow-up blood pressure, heart rate, echocardiographic findings, and P-wave values were not significantly different between the irbesartan and quinapril groups. No patient developed AF during follow-up. There was no significant correlation between PWD and blood pressure or diastolic function parameters.

CONCLUSION

Antihypertensive treatment with either irbesartan or quinapril is associated with significant reductions in Pmax and PWD.

Coronary Collateral Circulation: Any Effect on P-Wave Dispersion?

Coronary collateral circulation determines the severity of ischemic myocardial damage. Increased P-wave dispersion is an independent predictor for atrial fibrillation. Consistent evidence is little about the relation between coronary collateral circulation and arrhythmia risk. In this article, the effect of coronary collateral circulation on P-wave dispersion was evaluated. Collateral grade and P-wave dispersion were ascertained in 100 patients with ≥85% diameter stenoses in left anterior descending or right coronary arteries. Left ventricular function score was also determined in all patients. Coronary collateral circulation was absent in 32 patients, whereas 68 patients had coronary collateral circulation. Patients with collateral grade ≥1 had greater left ventricular function score than did patients with collateral grade 0 ( P = .048). However, there was no significant difference between P-wave dispersion of patients with and without coronary collateral circulation ( P = .45). The presence of coronary collateral circulation failed to exert a beneficial decreasing effect on P-wave dispersion.

Effect of ongoing inflammation in rheumatoid arthritis on P-wave dispersion

It has been emphasized recently that there is a strong association between atrial fibrillation and inflammation. Rheumatoid arthritis (RA), characterized by ongoing inflammatory activity, can increase the risk of atrial arrhythmia. P-wave dispersion has been encountered as a risk factor for atrial fibrillation and the effect of inflammation on P-wave dispersion has not been studied thoroughly. The aim of this study was to examine the effect of ongoing inflammatory activity in RA on P-wave dispersion. The study comprised 82 patients diagnosed with RA and 41 healthy volunteers as controls. Systolic functions of all participants were evaluated by echocardiography. Maximum P-wave duration and dispersion were calculated and found to be significantly increased in the RA group compared with the healthy controls. These parameters were also significantly correlated with C-reactive protein levels. The findings of this study suggest that RA may be associated with increases in P-wave dispersion and maximum P-wave duration, and that this association may result from ongoing inflammation.

Short-term effects of cilazapril and atenolol on P-wave dispersion in patients with hypertension

INTRODUCTION

P-wave dispersion (PWD) has been shown to be a non-invasive electrocardiographic predictor for development of atrial fibrillation (AF). Thus, it may be possible to decrease AF risk through improvement in PWD. Our objective was to compare the effects of cilazapril and atenolol on P-wave duration and dispersion in patients with hypertension.

METHODS

A total of 38 newly diagnosed hypertensive patients were enrolled in the study. The patients were randomly assigned to receive treatment with either cilazapril (5 mg) or atenolol (50 mg). Doppler echocardiographic examination, P-wave durations and PWD were measured before and 1 mo after treatment

RESULTS

Both drugs reduced blood pressure significantly (P<0.001). Posttreatment heart rate was significantly lower in the atenolol group (P=0.01). The change in maximum P-wave duration was not significant. However, both agents decreased PWD (P=0.001 and P<0.001) and increased the minimum P-wave duration (P=0.004 and P=0.02).

CONCLUSION

Both cilazapril and atenolol treatments resulted in improvement in PWD.

The effect of diabetes mellitus on the P-wave dispersion

BACKGROUND

P-wave dispersion (PD), a measure of heterogeneity of atrial refractoriness, is defined as the difference between the minimum (P min) and maximum P-wave (P max) durations on standard 12-lead electrocardiography (ECG). Increase in PD shows the intra-atrial and inter-atrial non-uniform conduction. In the present study the evaluation of the effect of diabetes mellitus (DM) on PD in patients without coronary artery disease and hypertension was carried out.

METHODS AND RESULTS

Seventy-six diabetic patients who had no coronary artery disease or hypertension (group 1; mean age 48+/-9) and 40 healthy volunteer individuals (group 2; mean age 46+/-13) were enrolled in the study. After obtaining 12-lead surface ECG of all cases, P max and P min P-wave durations were measured and the differences between them were taken as PD (PD=P max-P min). Left atrium diameter, left ventricular end systolic and end diastolic diameters were measured and left ventricular ejection fraction was determined by echocardiography. Pulse wave mitral flow velocities were measured from the apical 4-chamber view. Mitral early diastolic velocity (E), late diastolic velocity (A), E/A, E deceleration time and isovolumetric relaxation time were determined. In comparison of the 2 groups there was no statistically significant difference among age, sex, systolic and diastolic blood pressure, resting heart rate and body mass index of the cases. Although PD and P max were significantly higher in diabetic patients, there was no difference between P min values (33+/-12 vs 28+/-10, p=0.02; 99+/-12 vs 93+/-10, p=0.011; 66+/-9 vs 65+/-10, p=NS; respectively).

CONCLUSIONS

DM might increase PD even without ischemia, hypertension and left ventricular hypertrophy.

P-wave duration and dispersion in patients with peripheral edema and its amelioration

BACKGROUND

Attenuation of the P-wave amplitudes in patients with peripheral edema (PERED) has been recently reported, with P-waves regaining some of their amplitude in patients, who subsequently experienced amelioration of their PERED. Changes in the P-waves correlated with the corresponding alterations in the QRS complexes. Also since amplitudes and durations of QRS complexes changed in parallel in patients with PERED, it was hypothesized that similar changes in the P-wave amplitudes, mean P-wave duration (P-du-mean), and P-wave dispersion (P-d), would occur in such patients.

METHODS

Measurements of P-wave amplitude, P-du-mean and P-d in patients who developed, or experienced alleviation, of PERED, were carried out and analyzed.

RESULTS

Although P-wave amplitudes and P-wave areas decreased with development of PERED (N = 16), and increased with its amelioration (N = 6), P-dur-mean before PERED was 66.8+/-14.5 ms, and at peak weight gain it was 65.2+/-11.9 ms, p = 0.66; also at peak weight gain and subsequent lowest weight, in the patients who lost weight, it was 66.5+/-9.9 ms and 72.3+/-12.0 ms, respectively, p = 0.38. Similarly the P-d prior to PERED was 62.3+/-25.2 ms, and at peak weight gain it was 74.3+/-29.3 ms, p = 0.09; also at peak weight and subsequent lowest weight, in the patients who lost weight, it was 58.8+/-34.2 ms, and 61.3+/-13.6 ms, respectively, p = 0.87.

CONCLUSION

P-du-mean and P-d did not change in patients who developed PERED; their stability is attributed to the offsetting of the electrophysiologically-mediated real changes, by opposite apparent changes, imparted by PERED.

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.

The comparative effects of telmisartan and ramipril on P-wave dispersion in hypertensive patients: a randomized clinical study

BACKGROUND

Prolongation of P-wave times and increase of P-wave dispersion (PWD) were shown to be independent predictors of atrial fibrillation (AF). Angiotensin II receptor blockers (AARBs) and angiotensin-converting enzyme inhibitors (ACEIs) have beneficial effects on atrial conduction times. However, there are not enough data about the comparative effects of those drugs on PWD.

HYPOTHESIS

We aimed to compare the effects of telmisartan and ramipril on PWD after 6-month treatment in hypertensive patients.

METHODS

In all, 100 newly diagnosed hypertensive patients were enrolled in the study and were randomly assigned to two groups. Group 1 and Group 2 each consisted of 50 patients, taking daily doses of 80 mg telmisartan and 10 mg ramipril, respectively. Twelve-lead surface electrocardiograms (ECG) were recorded from all patients before and after 6-month drug therapy. The P-wave duration (Pdur) measurements were calculated from the 12-lead surface ECG.

RESULTS

When pretreatment PWD and Pmaximum values were compared with post-treatment values, a statistically significant decrease was found in both groups after 6 months (Group 1 and 2; p < 0.001 for PWD and Pmaximum). P-wave dispersion and Pmaximum values after treatment in Group 1 were statistically significantly lower than those in Group 2 after the 6-month treatment period (p = 0.01 for PWD; p = 0.008 for Pmaximum).

CONCLUSIONS

Telmisartan has a much greater lowering effect on PWD and Pmaximum values than ramipril. This finding may be important in the prevention of AF in hypertensive patients.

Doppler tissue analysis of atrial electromechanical coupling in paroxysmal atrial fibrillation

The aim of this study was to: (1) evaluate atrial electromechanical coupling using M-mode Doppler tissue; and (2) test its clinical impact for detecting atrial abnormalities in paroxysmal atrial fibrillation (AF). Using Doppler tissue, the time intervals from the onset of P wave until the backward motions of the right and left atrioventricular rings in the apical 4-chamber view corresponding to the atrial contractions were measured. In paroxysmal AF group, these intervals were significantly longer than in the control group. Using the criteria that an abnormal time interval from the onset of P wave until the backward motion of the left atrioventricular ring is longer than 112 milliseconds, the sensitivity, the specificity, and the positive predictive values for paroxysmal AF are 73%, 93%, and 93%, respectively. This parameter is affected in patients with paroxysmal AF and should be useful for detecting atrial impairment related to paroxysmal AF.

Increased P-wave dispersion predicts recurrent atrial fibrillation after cardioversion

Atrial fibrillation (AF) will recur in a number of patients treated with cardioversion. Being able to identify reliable risk factors would be useful for making management decisions. P-wave dispersion (PWD) is an electrocardiographic measurement, which reflects a disparity in atrial conduction. P-wave dispersion has been shown to be increased in patients with paroxysmal AF. This pilot study aims to determine the role of PWD in predicting AF recurrence in patients who underwent elective cardioversion. Forty-five patients who were successfully cardioverted for persistent AF were included for study. Eighteen patients had a PWD greater than 80 ms; of these 13 had AF recurrence. Of the 25 patients with PWD less than 80 milliseconds, 12 had recurrent AF. P-wave dispersion values greater than 80 milliseconds were found more frequently in patients with AF recurrence (P = .05), supporting the use of this parameter in predicting return of AF. Larger studies are needed for further evaluation.

Increases in P-Wave Dispersion Predict Postoperative Atrial Fibrillation After Coronary Artery Bypass Graft Surgery

Atrial fibrillation (AF) is a common complication after coronary artery bypass graft (CABG) surgery. In this study we examined the effect of surgery on atrial electrophysiology as measured by P-wave characteristics and to determine the potential predictive value of P-wave characteristics on the incidences of postoperative AF in patients undergoing CABG surgery. Patients undergoing elective CABG surgery were monitored by continuous electrocardiogram (ECG) telemetry during the in-hospital period until discharge for the occurrence of postoperative AF. Differences in P-wave characteristics (P-wave duration, amplitude, axis, dispersion, PR interval, segment depression, and dispersion) were compared between the pre- and postoperative 12-lead ECG measurements, and also between patients with and without postoperative AF. The association of postoperative AF and potential clinical predictors and P-wave characteristics were determined by multivariate logistic regression. Postoperative AF occurred in 81 (27%) of 300 patients. Univariate analysis showed that patients who subsequently developed postoperative AF compared with those without AF were significantly older (mean age 68 +/- 8 versus 63 +/- 10 yr, P < 0.0001), had a larger body surface area (BSA) (2.03 +/- 0.24 versus 1.92 +/- 0.22 m(2), P = 0.0002), were more likely to have a history of AF (8 of 81 versus 1 of 219, P = 0.003), used preoperative antiarrhythmic medications more frequently (7 of 81 versus 4 of 219, P = 0.01), and had a more frequent rate of return to the operating room for postoperative complications (9 of 81 versus 9 of 219, P = 0.029). Furthermore, the postoperative P-wave duration decreased to a larger extent (mean change -11.3 +/- 0.1 ms versus -8.4 +/- 0.1 ms, P < 0.0001), and the P-wave dispersion increased postoperatively to a larger extent (3.1 +/- 15.5 ms versus -1.6 +/- 14.6 ms, P = 0.028) in those who subsequently developed AF compared with those without AF. Multivariate logistic regression showed age (odds ratio [OR] = 1.1, 95% confidence interval [CI]: 1.06-1.15, P < 0.0001), BSA (OR = 38.1, 95% CI: 8.2-176, P < 0.0001), and an increase in postoperative P-wave dispersion (OR = 1.03, 95% CI: 1.01-1.05, P = 0.01) to be independent predictors of postoperative AF. No surgical factor was identified to be responsible for this postoperative change in atrial electrophysiology.

IMPLICATIONS

In addition to clinical factors, such as advanced age and body surface area, we demonstrated that electrophysiologic changes involving an increase in P-wave dispersion postoperatively independently predict atrial fibrillation after coronary artery bypass graft surgery.

The effect of exercise to P wave dispersion and its evaluation as a predictor of atrial fibrillation

AIM

Prolongation of P wave time and increase of its dispersion as an independent predictor of atrial fibrillation. In patients with paroxysmal atrial fibrillation (PAF) as in healthy people, exercise augments sympathetic activity and therefore can cause the development of atrial fibrillation. The aim of this study is to evaluate the effect of exercise on P wave dispersion and to predict the development of atrial fibrillation.

METHODS

One hundred and ninety-eight patients (93 women, 105 men, mean age: 59.05 +/- 11.01 years) having the diagnosis of PAF were included in the study. The left atrial diameter of all these patients was more than 4.0 cm. One hundred and fifty-five patients (72 females, 83 males, mean age: 58.41 +/- 10.79 years), with left atrial diameter more than 4.0 cm and without PAF were taken as control group. Symptom limited exercise test with modified Bruce protocol was performed on all patients. Rest, maximum exercise and recovery, and first, third, and fifth-minute 12-derivation ECG was taken in all patients. The velocity of ECG was adjusted to 50 mm/s; shortest and largest P wave durations were measured and P wave dispersion was calculated.

RESULTS

The mean left atrial diameter was 4.41 +/- 0.58 cm in PAF patients and 4.38 +/- 0.48 cm in control group. No differences were found between PAF patients with the controls in exercise time (10.38 +/- 2.93 vs 10.81 +/- 2.75 minutes); METs (6.98 +/- 1.72 vs 7.28 +/- 1.75 minutes); resting heart rate (79.13 +/- 14.86 vs 79.69 +/- 10.43 bpm); peak heart rate (146.83 +/- 23.21 vs 146.94 +/- 16.13 bpm). Maximum exercise P wave duration and P wave dispersion were greater than the rest measurements in PAF group (respectively P < 0.0001 and P = 0.0004).

CONCLUSION

In PAF patients, P wave dispersion is significantly longer at rest, maximum exercise and recovery time than in a control group without PAF.

A comparison of P-wave duration and dispersion in patients with short-term and long-term atrial fibrillation

This study compared P-wave duration and dispersion (PD) in patients with short-term (<or=48 hours) and long-term (>48 hours) atrial fibrillation (AF) after cardioversion. We studied 96 consecutive patients with short-term (group A; n:51, age: 61 +/- 11 years) and long-term AF (group B; n:45, age: 64 +/- 10 years). P-wave measurements were calculated from 12-lead electrocardiogram. There was no difference related to clinical characteristics. Left atrial dimension was significantly higher in group B (P =.003). P maximum (124 +/- 12 vs. 113 +/- 11 ms, P =.001) and PD (57 +/- 8 vs. 49 +/- 9 ms, P =.001) were also significantly longer in group B compared with group A, but P minimum did not. In univariate analysis, PD were related to AF duration (P =.002) and left atrial size (P =.02). This relation remained in multivariate analysis (P =.01, P =.02, respectively). P maximum >112 ms and PD >47 ms had accuracy values of 74% and 83% respectively for separating group B. Our results suggest that P wave duration and dispersion is prolonged in patients with long-term AF compared to short-term AF.

Long-term effects of beta blocker therapy on P-wave duration and dispersion in congestive heart failure patients: a new effect?

Atrial fibrillation (AF) is associated with heart failure in approximately 20%-50% of patients with increased morbidity and mortality. P-wave maximum duration (PWM) and P-wave dispersion (PWD) are recent ECG markers and reflect increased risk of AF. The aim of our study was to investigate the long-term effects of metoprolol on atrial conduction abnormalities as estimated by PWM and PWD, which were calculated on 12-derivation surface ECG in heart failure patients. Forty-two NYHA class 3 to 4 patients (23 males, 19 females and aged 52.9 +/- 11.2) were enrolled in the study. At the end of the 6 months, PWM and PWD values were significantly decreased (for PWM: from 115.2 +/- 12.6 to 105.4 +/- 13.5; for PWD: from 39.3 +/- 9.1 to 28.6 +/- 10.5; P <.001 for both). Metoprolol treatment is associated with a decreased duration of PWM and PWD and this may reflect a reduction in the probability of atrial fibrillation in heart failure patients.

Effect of diuresis on P-wave duration and dispersion

STUDY OBJECTIVE

To evaluate the effects of changing volume status on P-wave duration and dispersion in patients with decompensated heart failure.

DESIGN

Prospective analysis.

SETTING

Hospital cardiology unit.

PATIENTS

Twenty-one patients with symptoms of decompensated heart failure who were treated with diuretics on admission.

INTERVENTION

Twelve-lead electrocardiograms were obtained at baseline and after diuresis. Average, minimum, and maximum P-wave duration and P-wave dispersion (minimum minus maximum duration) were determined.

MEASUREMENTS AND MAIN RESULTS

P-wave duration was measured manually in all 12 leads by using a 0.5-mm-scale precision ruler and magnifying lens. After 40+/-23 hours of diuresis, 3+/-1 L of fluid was removed. A significant correlation was found between average P-wave duration and amount of fluid removed (r = -0.59, p=0.015). Also, average and maximum P-wave duration were significantly decreased with diuresis (p=0.001 and 0.022, respectively). No other P-wave variables were significantly affected.

CONCLUSIONS

Diuresis may attenuate electrophysiologic changes caused by fluid overload.