Study of P wave dispersion in patients with paroxysmal atrial fibrillation and its role in prediction of atrial fibrillation recurrence.

BACKGROUND: It has been known that increased P wave duration and P wave dispersion reflect prolongation of intra-atrial and interatrial conduction time and the inhomogeneous propagation of sinus impulses, which are well-known electrophysiologic characteristics in patients with atrial arrhythmias and especially paroxysmal atrial fibrillation. The objective of this study was assessment of P wave dispersion value in cases with paroxysmal atrial fibrillation and its role in predicting recurrence. RESULTS: Forty-eight patients with documented paroxysmal AF were subjected to clinical evaluation, electrocardiogram and routine Doppler echocardiogram. We found that a statistically significant association was detected between P wave dispersion and older age, diabetic and hypertensive cases with positive correlation also detected with left atrial dimension (LAD), left ventricle size and diastolic dysfunction grade. Mean corrected P wave dispersion and corrected QT interval were higher among cases using sotalol, ca channel blockers, among cases using nitrates and among cases with Morris index > 0.04. Higher mean value of corrected QT was associated with biphasic P v1 shape. Old age, female sex, P wave dispersion and QT wave dispersion are statistically significant predictors of PAF recurrence. CONCLUSION: P wave dispersion in patients with paroxysmal atrial fibrillation was strongly correlated to older age, diabetic and hypertensive patients and also with left atrial dimension (LAD), left ventricle size and diastolic dysfunction grade. Also, mean corrected P wave dispersion can predict atrial fibrillation recurrence in patients with Morris index > 0.04, old age, female sex, and QT wave dispersion.

The Effect of Glycemic Status on P Wave Dispersion.

Background and aim The growing number of people with diabetes mellitus (DM) across the world is a public health concern. The diabetes epidemic involves enormous health costs to the patients, their careers, and society at large. Cardiovascular diseases such as atrial fibrillation (AF) often develop in the diabetic population. An increase in the P wave dispersion (PWD) has been established as an independent risk factor for the occurrence of AF, hence the present study was conducted to establish a possible relationship between PWD and the glycemic status of the individual to predict the occurrence of AF ahead of clinical symptomology. Methodology A comparative cross-sectional study was conducted at a tertiary care hospital after obtaining approval from the institutional ethics committee and written consent of each study subject. The main steps included the selection and categorization of the study population based on their glycemic status, collection of demographic data, performing ECGs calculating PWD using digital calipers, and recording the data systematically for evaluation. Results In this study, 234 patients with a mean age of 53.3 ± 13.1 years were studied, of which 121 (51.7%) were male and 113 (48.29%) were female. The 234 patients were divided into four groups based on their glycemic status - 74 uncontrolled DM patients (31.62%), 51 type 2 DM (T2DM) patients (21.78%), 56 prediabetes patients (23.93%), and 53 patients in the control group (22.64%; not a known case of diabetes with normal HbA1c and fasting blood sugar (FBS) levels). Minimal correlation was observed between FBS with PWD (r value 0.175) and age with PWD (r value 0.161), but statistical significance was observed only between age and PWD (p-value 0.014). The difference in means between the four different study groups was found to be not statistically significant (p-value- 0.104); hence, no intergroup variation was noted. Conclusion Advancing age and higher fasting blood sugars have shown minimal correlation with widening P-wave dispersion. With further studies involving larger populations, this can be a promising aid in identifying PWD as a probable early predictor of atrial arrhythmias among diabetic patients.

Predictor of A4 amplitude using preprocedural electrocardiography in patients with leadless pacemakers.

BACKGROUND: Based on historical studies of leadless pacemakers (LPs), high atrioventricular synchrony (AVS) with mechanical sensing-based VDD pacing is largely influenced by A4 amplitude. A limited study investigated the predictors of A4 amplitude using clinical and echocardiographic parameters. OBJECTIVE: The purpose of this study was to investigate the predictors of A4 amplitude preoperatively to select patients who could benefit the most from AVS among patients with VDD LPs (Micra-AV, Medtronic). METHODS: Data from patients who received Micra-AV implantations from November 2021 to August 2023 at Tottori University Hospital were analyzed. Twelve-lead electrocardiography and transthoracic echocardiography were performed before the Micra-AV implantations. To assess the electrical indices associated with the A4 signal, electrocardiographic morphologic P-wave parameters were analyzed, including P-wave duration, P-wave amplitude, maximum deflection index (MDI), and P-wave dispersion. RESULTS: A total of 50 patients who underwent Micra-AV implantations (median age 84 years; 64% male) were included and divided into 2 groups based on the median value of A4 amplitude, the high-A4 group (A4 amplitude >2.5 m/s2; n = 26), and low-A4 group (A4 amplitude ≤2.5 m/s2; n = 24). There was a significant difference between the high-A4 and low-A4 groups with regard to left ventricular ejection fraction (P = .01), P-wave dispersion (P = .01), and MDI (P <.001). Multivariate logistic analysis revealed that lower MDI was an independent predictor of high A4-amplitude (odds ratio 0.78; 95% confidence interval 0.67-0.92; P = 0.003). CONCLUSION: Preoperative electrocardiographic evaluations of P-wave morphology may be useful for predicting A4 amplitude. MDI was the only independent A4 amplitude predictor that seemed promising for selecting Micra-AV patients.

Evaluation of cardiac electrophysiological features in patients with premature adrenarche.

OBJECTIVES: This study aimed to analyze the cardiac effects of hyperandrogenism in premature adrenarche (PA) and evaluate the risk of arrhythmia development. METHODS: Fifty patients with PA and 50 healthy children from a pediatric endocrinology outpatient clinic were included in the study. The patients underwent echocardiography and electrocardiographic evaluations. Conventional echocardiography, tissue Doppler echocardiography, repolarization time, and repolarization dispersion time were evaluated. RESULTS: The median age in the PA and control groups was 7.91 years (5.83-9.25), 8.08 years (5.75-9.33), respectively. Thirty percent of patients in the PA group were male. While mitral early diastolic velocity deceleration time (DT), isovolumetric relaxation time (IRT), and E/e' ratio were significantly higher in the PA group than in the control group, mitral lateral annulus tissue Doppler early diastolic velocity was significantly lower (p=0.0001, 0.0001, 0.003, 0.0001). While P wave dispersion (PWD), Tpe, and QT-dispersion (QT-d) values were significantly higher in the PA group than in the control group, the P minimum value was significantly lower in the PA group (p=0.0001, 0.02, 0.004, and 0.0001, respectively). CONCLUSIONS: Early subclinical diastolic dysfunction was observed in the PA group. There was an increased risk of atrial arrhythmia with PWD and an increased risk of ventricular arrhythmia with increased Tpe and QT-d. There was a correlation between testosterone levels and diastolic function parameters. The increased risk of atrial arrhythmia is closely related to diastolic function.

P-wave peak time and P-wave dispersion in surface electrocardiography as initial predictors of new-onset atrial fibrillation in early-onset hypertension.

Atrial fibrillation (AF) is common in hypertension, and electrophysiological remodelling may contribute to the early stage of the disease. This study aimed to develop electrocardiography (ECG) prediction models on new-onset AF (NAF) in early-onset hypertension (e-HTN). This matched case-control study included primary hypertension patients with onset <5 years defined as e-HTN and without documented AF. Developed NAF was the risk group and non-developed NAF was control group with 1:2 ratio. Group was matched according to age, gender, follow-up time, and duration of hypertension. Parameters of ECG and echocardiography between the groups at the baseline and end of follow-up will be compared. A total of 348 e-HTN with 116 developed NAF during follow-up (60.2 ± 14.5 months) were included. At baseline ECG, duration of QRS (100.84 ms ± 15.69 ms vs 94.80 ms ± 15.68 ms), Pmax (106.75 ms ± 7.93 ms vs 101.77 ms ± 6.78 ms), Pmin (70.24 ms ± 5.59 ms vs 68.17 ms ± 5.61 ms), P-wave dispersion (PD) (36.50 ms ± 5.25 ms vs 33.60 ms ± 5.46 ms), P-wave Peak Time (PWPT) II (62.01 ms ± 3.92 ms vs 54.29 ms ± 6.73 ms), and PWPT V1 (55.31 ms ± 2.89 ms vs 51.24 ms ± 4.05 ms) were significantly higher in developed NAF (all P-value < 0.05). LVMI was also significantly higher in bivariate analysis, but only Pmax, Pmin, PD, PWPT, non-RAAS inhibitor, and uncontrolled hypertension were independently associated with developed NAF. Baseline PWPT II with cut-off ≥57.9 ms and PD ≥ 35.5 ms has high sensitivity and specificity on NAF prediction. In conclusion, baseline PWPT and PD are potential electrophysiological parameters for predicting NAF in e-HTN.

Mid-Term Electrical Remodeling after Percutaneous Atrial Septal Defect Closure with GCO Device in a Pediatric Population.

BACKGROUND AND AIM: The GORE® CARDIOFORM (GCO) septal occluder is an atrial septal defect/patent foramen ovale closure device with theoretical advantages over other commercialized devices thanks to its softness and anatomical compliance. Our aim was to evaluate the short- and medium-term electrocardiographic changes after percutaneous ASD closure with GCO in a pediatric population. METHODS: We enrolled 39 patients with isolated ASD submitted to trans-catheter closure from January 2020 to June 2021. ECG was performed before, at 24 h and 6 months after the procedure. P wave dispersion, QTc and QTc dispersion were calculated. ECG Holter was recorded at 6 months after implantation. RESULTS: Patients' age and body surface area (BSA) were 8.2 ± 4.2 years and 1.0 ± 0.3 m2 respectively. At the baseline, mean P wave dispersion was 40 ± 15 msec and decreased at 24 h (p < 0.002), without any further change at 6 months. At 24 h, PR conduction and QTc dispersion significantly improved (p = 0.018 and p < 0.02 respectively), while the absolute QTc value considerably improved after 6 months. During mid-term follow-up, QTc dispersion remained stable without a significant change in PR conduction. The baseline cardiac frequency was 88.6 ± 12.6 bpm, followed by a slight reduction at 24 h, with a further amelioration at 6 months after the procedure (87.3 ± 14.2, p = 0.9 and 81.0 ± 12.7, p = 0.009, respectively). After device deployment, two patients developed transient, self-limited junctional rhythm. One of them needed a short course of Flecainide for atrial ectopic tachycardia. No tachy/brady-arrhythmias were recorded at the 6-month follow-up. ASD closure resulted in a marked decrease in right heart volumes and diameters at 6 months after percutaneous closure. CONCLUSIONS: Percutaneous ASD closure with the GCO device results in significant, sudden improvement of intra-atrial, atrio-ventricular and intraventricular electrical homogeneity. This benefit persists unaltered over a medium-term follow-up. These electrical changes are associated with a documented positive right heart volumetric remodeling at mid-term follow-up.

Analysis of relationship between P wave dispersion and diagnosis of pulmonary arterial hypertension and risk stratification.

BACKGROUND: The aim of this study was to measure the P-wave dispersion(PWD) in the ECG of patients with pulmonary arterial hypertension(PAH). METHODS: A total of 103 PAH patients were collected, including 55 patients related with congenital heart disease(CHD) and 44 patients with idiopathic pulmonary arterial hypertension(IPAH). In addition, 30 CHD patients without PAH (nPAH-CHD group) and 30 healthy controls (HCG group) were collected as control. Patients in the PAH group were categorized into the low-risk group (30 cases), moderate-risk group (53 cases) and high-risk group (20 cases), followed by comparison of PWD difference between groups. The ROC curve was used to evaluate the diagnostic efficacy of PWD on PAH-CHD and IPAH. RESULTS: The levels of PWD and maximum P wave duration(Pmax) in PAH-CHD and IPAH group were significantly higher than those in nPAH-CHD and HCG group (P < 0.05). PWD level was positively correlated with right ventricular end-diastolic diameter(RVD), right atrial end-systolic diameter(RAS), mean pulmonary arterial pressure(mPAP), pulmonary vascular resistance(PVR)(r = 0.407, 0.470, 0.477, 0.423, P < 0.001), and was negatively correlated with systolic displacement of tricuspid valve annulus(TAPSE) level (r = -0.551, P < 0.001). After risk quantification in 103 PAH patients, we found that PWD was significantly different among the low-risk, moderate-risk and high-risk groups (43.89 ± 9.91 vs. 51.29 ± 6.61, 62.15 ± 10.44, P < 0.001). CHD-PAH and IPAH were identified by PWD with a cut off value of 41.5 ms (P < 0.001), and a cut off value of 41.45 ms (P < 0.001), respectively. CONCLUSIONS: PWD might be an effective ECG indicator for PAH, which might be used as a relatively economical indicator for PAH patients to assist in early diagnosis, disease severity assessment and prognosis evaluation.

Atrial electromechanical delay in post-COVID-19 postural orthostatic tachycardia: Innocent bystander or pathologic factor.

BACKGROUND: Post-COVID-19 syndrome represents a wide range of ongoing symptoms that persist beyond weeks or even months, after recovery from the acute phase. Postural orthostatic tachycardia (POT) is one of these symptoms with a poorly recognized underlying pathophysiology. PURPOSE: We aimed to investigate atrial electromechanical delay (AEMD), demonstrated by electrocardiographic P wave dispersion (PWD) and tissue Doppler echocardiography (TDE) in patients with POST-COVID-19 POT (PCPOT). METHODS: 94 post-COVID-19 patients were enrolled and classified into two groups; PCPOT group, 34 (36.1%) patients, and normal heart rate (NR group), 60 (63.9%) patients. 31.9% of them were males and 68.1% were females, with a mean age of 35 ± 9 years. Both groups were compared in terms of PWD and AEMD. RESULTS: As compared to the NR group, the PCPOT group showed a significant increase in PWD (49 ± 6 versus 25.6 ± 7.8, p < 0.001), higher CRP (37 ± 9 versus 30 ± 6, p = 0.04), prolonged left-atrial EMD, right-atrial EMD and inter-atrial EMD at (p = 0.006, 0.001, 0.002 respectively). Multivariate logistic regression analysis revealed that P wave dispersion (ß 0.505, CI (0.224-1.138), p = 0.023), PA lateral (ß 0.357, CI (0.214-0.697), p = 0.005), PA septal (ß 0.651, CI. (0.325-0.861), p = 0.021), and intra-left atrial EMD (ß 0.535, CI (0.353-1.346) p < 0.012) were independent predictors of PCPOT. CONCLUSION: Atrial heterogenicity in the form of prolonged AEMD and PWD seems to be a reasonable underlying pathophysiology of PCPOT. This could provide a new concern during the management and novel pharmacological approaches in these patients.

Increased P-wave dispersion in patients with obstructive sleep apnea syndrome: a meta-analysis.

PURPOSE: Prolonged atrial conduction and inhomogeneous sinus impulse propagation may play a role in the initiation and maintenance of atrial tachyarrhythmias. Such a process could be reflected in inter-lead P-wave duration differences known as "P-wave dispersion" (PWD). Abnormal PWD may be related to obstructive sleep apnea syndrome (OSAS). A meta-analysis of the available publications was conducted. METHODS: A MEDLINE, Web of Science, and Google Scholar search from 2000 to 2021 was performed. The keywords used for search were apnea AND "P wave dispersion." Case-control studies and surveys were selected as long as they included healthy subjects and subjects with diagnosed OSAS who did not have any other major health problems. PWD values and correlations between apnea-hypopnea indices (AHI) and PWD were used as outcome measures. RESULTS: Ten studies met the inclusion creteria, encompassing 773 patients with OSAS and 347 healthy controls. The mean ages of the patients with OSAS ranged from 6.9 to 58.8 years. The estimated average Hedges's g standardized mean difference in PWD values was equal to 1.883 (95% CI: 1.140 to 2.626, p < 0.001). The estimated average Fisher r-to-z transformed correlation coefficient between AHI and PWD was equal to 0.530 (95% CI: 0.075 to 0.985, p = 0.0225). Meta-regression analysis failed to find statistically significant correlations between the effect sizes and the mean age, male proportion, and the body mass index in the OSAS groups. CONCLUSION: OSAS is associated with increased PWD, which may predispose to atrial tachyarrythmias.

Evaluation of the Cardiac Conduction System in Fibromyalgia Patients With Complaints of Palpitations.

Objective This study aimed to investigate the influence of fibromyalgia syndrome (FMS) on the cardiac conduction system and assess patients' palpitation complaints using 24-h ambulatory ECG (Holter {Maynard, MA: Northeast Monitoring, Inc.}) monitoring. Methods Ninety patients with FMS and 70 healthy controls were included in this research. ECG was performed on all participants, and ECG parameters were calculated. Holter monitoring was conducted, and the recordings were analyzed. The results of time-domain heart rate variability (HRV) were evaluated. Results The patient group's mean age was 38.3±6.3 years. There were no statistically significant differences in demographic or laboratory parameters across the groups (p>0.05). The findings of a 24-h Holter ECG recording did not vary significantly between the groups (p=0.182). In the study group, the values for the standard deviation of R-R intervals (SDNN), low frequency (LF), and low/high frequency (LF/HF), which are known as HRV indicators, were substantially different between the two groups (p<0.05). Conclusions The study indicated that the risk of arrhythmias did not increase even though FM patients complained of palpitations.

Evaluation of ECG Repolarization Parameters in a Worker Cohort Working the Night Shift.

Objectives: Night Shift work is an increasingly common working order that affects human well-being and it is little known about its arrhythmic role in the cardiovascular system. We aimed to investigate the effect of working at night shifts on P-wave dispersion (Pd), QT and QTc dispersions (QTd, QTcd resp) on surface electrocardiography. Methods: We included 286 foundry workers who work at night shift and 100 foundry workers who work on day time only. The night shift workers were divided into three subgroups according to the length of time they worked at night shift. Surface electrocardiography and blood tests were applied for all participants. Results: Pd, QTd and QTcd values increased in the night shift workers compared to the day time workers (p < 0.05). In subgroup analysis; the night shift workers for more than 15 years had a significantly higher Pd, QTd and QTcd compared to others (p < 0.001). Correlation analysis revealed significant positive correlations with working duration and Pd (r = 0.578, p < 0.001) and QTcd (r = 0.417, p < 0.001). In the linear regression analysis, working duration at night shift was significantly associated with Pd and QTcd values, independent from other associated clinical risk parameters. Conclusions: This study makes one of the first attempts to assess changes in ECG parameters reflecting tendency to rhythm disturbances, in night shift workers. Our results further underline the importance of covering a comprehensive evaluation of ECG in periodical health check-ups in night shift workers to evaluate the risk of both atrial and ventricular arrhythmias.

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.

Use of P wave indices to evaluate efficacy of catheter ablation and atrial fibrillation recurrence: a systematic review and meta-analysis.

BACKGROUND: To investigate the changes of P wave indices in atrial fibrillation (AF) patients after catheter ablation and the association between P wave indices and AF recurrence. METHODS: PubMed, Embase, and Cochrane Database were searched through September 15th 2021 for studies on the association between P wave indices and AF with catheter ablation. Heterogeneity was estimated using the I2 statistic, the random effects model was used to calculate the pooled results, and summary receiver operating characteristic curve (SROC) was used to evaluate the predictive value. RESULTS: Among included fourteen studies with 1674 AF patients, we found significantly decreased P wave dispersion (Pdis) (mean difference [MD]: - 6.5 ms, 95% confidence interval [95% CI]: - 11.81 to - 1.18, P = 0.02) after cryoballoon ablation (CBA) or radiofrequency ablation (RFA), and maximum P wave (Pmax) (MD: - 8.57 ms, 95% CI: - 17.03 to - 0.10, P = 0.05) after RFA only, but increased minimum P wave (Pmin) (MD: 3.43 ms, 95% CI: 1.07 to 5.79, P < 0.01) after CBA only. Pdis measured before ablation was remarkably higher (MD: 5.79 ms, 95% CI: 2.23 to 9.36, P < 0.01) in patients with recurrence than without; meanwhile, Pmax was higher measured both before and after ablation (MD: 6.49 ms, 95% CI: 2.30 to 10.69, P < 0.01 and MD: 11.2 ms, 95% CI: 2.88 to 19.52, P < 0.01). Furthermore, SROC analysis showed acceptable predictive efficiencies of Pdis (AUC = 0.776) and Pmax (AUC = 0.759) for AF recurrence. CONCLUSION: Pdis was significantly decreased after AF catheter ablation. Higher Pdis and Pmax may have predictive values for AF recurrence.

The relationship of benign prostatic hyperplasia's symptoms severity with the risk of developing atrial fibrillation.

Background: Attention is drawn to the increased incidence of atrial fibrillation (AF) in benign prostatic hyperplasia (BPH) patients recently. Early predicting of AF in these patients can help in decreasing its clinical consequences. The aim of our study is to determine the association between BPH symptoms and AF predictors atrial electromechanical delay (AEMD) and the P-wave dispersion (PWD). Methods: 218 healthy individuals recently diagnosed with BPH were assigned into three groups according to symptoms severity using the International prostate symptom score (IPSS) questionnaire. The first group with mild symptoms (IPSS score between 0 and 7, n = 78), the second group with moderate symptoms (IPSS score between 8 and 19, n = 86), and the third group with severe symptoms (IPSS score between 20 and 35, n = 54). PWD and AEMD calculations were performed for all participants. Results: There were statistically significant differences between the three groups in terms of AEMD and PWD (p < .01 and p < .01, respectively). In all three study groups, a significant positive correlation was observed between IPSS questionnaire scores and both AEMD and PWD (for AEMD r = .29, p = .013 and for PWD r = .27, p = .017). On the other hand, there were significant differences between the three groups in terms of the inflammatory markers C-reactive protein (CRP) and fibrinogen (p < .01 and p < .01, respectively) and in terms of serum testosterone levels (p < .01). Conclusions: We concluded that periodic evaluation of patients with BPH in terms of symptoms severity can be helpful not only from urological aspect, but also in the early prediction of possible serious cardiovascular morbidity and mortality.

Risk of Atrial Fibrillation in Pemphigus Vulgaris.

Background: Pemphigus vulgaris (PV) is a rare immunobullous disease with a higher mortality rate than the general population. The aim of this study was to investigate P-wave duration and P-wave dispersion (PWD) in patients with PV as predictors of atrial fibrillation (AF). Materials and Methods: In this case-control study, the risk of AF development was determined by measuring maximum and minimum P-wave duration (P-max and P-min) and PWD in 45 PV patients and 45 healthy individuals. The incidence of metabolic syndrome was evaluated. Results: PWD and P-max values of the study group were significantly higher than those of the control group. No difference was observed between PWD with regards to disease duration and disease phenotype (p > 0.05). There was no significant difference regarding the prevalence of metabolic syndrome in PV patients compared with the control group. Conclusion: PWD and P-max, which are accepted as risk factors for AF development, were found to be higher in PV patients. Some components of metabolic syndrome were more prevalent in PV patients. It seems that there is an increased risk of CVD and AF in PV patients.

Relationship between left atrial scar and P wave dispersion in patients undergoing atrial fibrillation catheter ablation.

BACKGROUND: Left atrial scar is an important entity in the atrial fibrillation substrate. P wave dispersion (PWD) is an indicator of slow and inhomogeneous conduction in the atria. In this study, we aim to investigate the relation between PWD and left atrial scars identified by electroanatomical mapping. METHODS: Patients who had an electroanatomical map obtained during sinus rhythm as well as at least one electrocardiogram in sinus rhythm prior to the procedure were included in the study. Left atrial scar (defined as <0.5 mV) area was calculated on the electroanatomical map. Maximum and minimum P wave duration and PWD were compared between patients with and without left atrial scar. RESULTS: A total of 224 patients were enrolled in the study. Of them, 47.9% of the patients were female. On the electroanatomical map, left atrial scar was identified in 103 patients, and no scar was present in 121 patients. PWD was significantly increased in patients with left atrial scar when compared to the no-scar group (46 ms ± 20 vs. 38 ms ± 15, respectively, p < 0.001). Similarly, PWD was significantly increased in patients with moderate-to-severe scar, when compared to patients with mild scar (50 ms ± 19 vs. 41 ms ± 19, respectively, p = 0.026). PWD was found not to be a good predictor of left atrial scar with an AUC of 0.625 for scar vs. no scar. CONCLUSION: PWD is significantly increased in patients with left atrial scar identified by electroanatomical mapping, however, the receiver operating characteristic analysis showed that PWD is not a good predictor of presence of left atrial scar.

RISK PREDICTION FOR ARRHYTHMIA IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE.

OBJECTIVE: The aim: To evaluate P-wave dispersion (PwD), as an independent predictor of atrial fibrillation, corrected QT interval dispersion (cQTD), the noninvasive marker of ventricular arrhythmia and sudden cardiac death, investigate the atrial electromechanical delay in patients with COPD and assess their relation with the severity of the disease. PATIENTS AND METHODS: Materials and methods: We prospectively enrolled consecutive patients with newly diagnosed COPD (n = 53, age 41.2 ± 6.8 years), compared with an age-matched healthy control group (n = 51, age 40.9 ± 6.5 years). A standard 12-lead electrocardiogram of each patient was analyzed for PwD and сQTD. Atrial electromechanical delay was analyzed by echocardiographic tissue Doppler imaging. The difference between PAs-PAl, PAs-PAt, and PAl-PAt were defined as left intra-atrial, right intra-atrial, and interatrial electromechanical delays (EMD), respectively. RESULTS: Results: PwD was higher in COPD patients than in control subjects (39.47 ± 3.12 ms vs. 30.29 ± 3.17 ms, p < 0.05). In comparison between control group and COPD subgroups (mild, moderate and severe), there was a statistically significant difference among these free groups in terms of PwD. Subgroup analyses showed that this difference was mainly due to patients with severe COPD. Regarding cQTD, there was a statistically significant increase in COPD patients 57.92 ± 3.43 ms vs 41.03 ± 5.21 ms, p < 0.05 respectively. PAs, PAl and PAt durations, right intra-atrial and interatrial EMD were also significantly longer in COPD patients (p < 0.05). Furthermore, there were significant negative correlations between FEV1 and PwD (r = - 0.46, p < 0.05), right intra-atrial (r = - 0.39 ms, p < 0.05), interatrial EMD ( r = - 0.35 ms, p < 0.05) and cQTD (r = - 0.32, p < 0.05). CONCLUSION: Conclusions: Atrial conduction time, such as inter- and intra-atrial EMD intervals, PwD and cQTD were longer than in healthy controls and correlated with the severity of COPD. These parameters offer a non-invasive and cost-effective assessment method for detecting patients at high risk of arrhythmia. Nevertheless, further prospective investigations on this issue are required.

The P wave dispersion-one pixel, one millisecond.

The electrophysiological activity of the heart is recorded and presented in form of electrocardiogram (ECG). In 1998 the concept of P wave dispersion as the risk factor for atrial fibrillation (AF) recurrence was introduced. It was calculated as the difference between the longest and the shortest P wave. The aim of our study is to prove that the P wave dispersion is an artifact of low accuracy in P wave measurement. The study included 186 patients (78M 108F) aged 59.7 ± 12.9 years, undergoing various electrophysiological procedures. The P wave was measured twice: first, at the paper speed of 50 mm/s, enhancement 8× (standard - imprecise) and the second time at 200 mm/s, 64-256× (precise). The imprecise measurement method resulted in different duration of all P wave parameters in comparison with precise measurement. The difference between Δ P max and Δ P min indicated a higher value for the latter parameter. It was indicated that the imprecise P wave dispersion value correlated most significantly with the maximal P wave duration, which was measured in a similar way. In contrast with the imprecise measurement method, the minimal and maximal durations of the P waves, being measured accurately, were almost identical. Using precise methodology, the P wave dispersion reaches negligible values and tends to zero. The measurements of the P wave have to be precise to assure the highest scientific and medical sincerity. The highest clinical value is related to the P wave duration.