环肺静脉线性消融术对P波时限及离散度的影响

目的 对比环肺静脉线性消融术前、术后P波时限和P波离散度,发现环肺静脉线性消融对以上参数的影响.方法 50例阵发性房颤患者,描记消融术前及术后7天窦性心律下同步12导联心电图,分析比较各导联P波时限及P波离散度,术后定期根据症状及动态心电图随访判断手术成功与否.结果 P波时限:Ⅱ、Ⅲ、aVR、V3、V4、V5导联P波时...     

P波触发P波信号平均心电图预测冠状动脉旁路移植术后心房纤颤

房颤常见于冠状动脉旁路移植术后,尚无准确和普遍公认的预测方法。54例患者冠状动脉旁路移植术前记录P波触发P波信号平均心电图。剔除P波信号平均心电图无法评估的6例病人和术后非房颤心律失常的3     

甲亢患者的P波离散度观测

目的分析甲亢患者P波离散度（Pd）变化与心房颤动发生的相关性。方法对比67例甲亢者和67例体检人群的同步12导联心电图,测算P波最大时限（Pmax）,P波最小时限（Pmin）,平均最长时限（平均Pmax）,P波离散度（Pd）及两组间Pd≥40ms的比较。结果甲亢组P波离散度≥40ms者明显高于对照组,且心房颤动发生者也明显高于对照组。结论P波离散度（Pd）是预测甲亢患者发生心房颤动的简易而独立的体表心电图观察指标。     

P波离散度对肥厚型心肌病患者发生房颤的预测价值

目的评价P波离散度及左房内径对肥厚型心肌病患者发生房颤的预测价值。方法158例肥厚型心肌病患者按是否伴有房颤分为房颤组和非房颤组,分别测量两组患者的心电图P波最大时限、P波最小时限并计算P波离散度,同时用超声心动图测量左房内径,并进行比较。结果158例患者中,32例患者伴房颤(20.3%)。其中阵发性房颤14例(43.7%),持续性房颤18例(57.3%),无症状性房颤5例(15.6%);房颤组与非房颤组P波最大时限、P波离散度及左房内径明显增加(p<0.01);房颤组与非房颤组患者比较,心电图P波最大时限>140ms、P波离散度>40ms和左房直径>42mm有显著性差异。结论肥厚型心肌病伴房颤患者中无症状性房颤较常见;P波最大时限>140ms、P波离散度>40ms和左房直径>42mm是预测发生房颤的可靠指标。     

房颤导管消融术前后最大P波时限及离散度与术后复发的关系

目的 观察房颤导管消融术前后最大P波时限(Pmax)及P波离散度(Pd)的变化规律,并探讨其对术后复发的预测价值.方法 选取31例行导管消融术治疗的阵发性心房颤动患者.消融术式采用三维标测系统联合单环状标测电极指导下肺静脉前庭隔离术,必要时辅以左右房辅助线线性消融,术后定期随访,并根据症状及心电图判断是否复发,并将患者分为消融成功组与术后复发组,测量12导联体表心电图各导联Pmax,并计算Pd;结果 术后复发组各时点Pd均显著高于消融成功组,差异有统计学意义(P<0.05);Pmax差异无统计学意义(P>0.05).若以40 ms为界值,术前Pd预测术后复发的灵敏度为83.3%,特异度为52.0%,阳性预测值29.4%,阴性预测值92.9%;术后24 h及1周时Pd预测术后复发的灵敏度为83.3%,特异度为68.0%,阳性预测值38.5%,阴性预测值94.4%.结论 术前及术后各时点P波离散度对房颤导管消融术后复发具有预测价值,而Pmax对术后复发无预测价值.     

阵发性房颤患者心电图P波形态的分析

目的 探讨体表心电图P波形态与阵发性心房颤动(PAF)的关系.方法 选择52例非瓣膜性阵发性房颤患者及47例无PAF的对照组患者,测定窦性心律时12导联心电图P波离散度(Pd),最大P波时限( Pmax),V1导联P波终末电势(Ptfv1)及aVR导联P波面积和振幅,超声心动图测定左房内径(LAD)、左室舒张末期内径(...     

阵发性房颤患者射频消融术后心电图P波离散度的变化

目的：探讨阵发性房颤射频消融术对 P 波离散度（最大、最小 P 波时限之差）的影响。方法：对95例有阵发性房颤病人行环肺静脉电隔离术,记录术前及术后24h 十二导心电图,测量最大、最小 P 波时限,计算 P 波离散度。从术后3个月开始,每月门诊随访,并行动态心电图检查,随访6个月。根据房颤症状及动态心电图随访资料判断手术成功与否分为成功组（70例）和复发组（25例）。结果：所有房颤患者射频消融术后 P 波离散度较术前均有下降[（42.22±4.02）ms 比（48.84±4.08）ms,P ＜0.01]。成功组 P 波离散度较术前明显下降[（40.67±4.82）ms 比（47.63±3.58）ms,P ＜0.01],复发组较术前有所下降[（48.26±3.48）ms 比（49.51±1.64） ms],但无显著性差异（P ＝0.346）。环肺静脉电隔离术后,成功组 P 波离散度显著低于复发组 P 波离散度（P ＜0.01）。结论：环肺静脉电隔离术可改善房颤患者 P 波离散程度,成功组 P 波离散度改善更加明显。环肺静脉电隔离术后 P 波离散度对房颤的复发有预测作用。     

P波离散度与冠脉搭桥术后阵发性心房颤动关系的临床探讨

目的 探讨P波离散度与冠脉搭桥术后阵发性心房颤动(阵发性房颤)的关系.方法 选取2004年-2007年我院心脏中心住院的冠脉搭桥术后并发阵发性房颤病人63例为阵发性房颤组,同期住院的冠脉搭桥术后未发生阵发性房颤病人71例为对照组,记录12导联同步心电图,测量术前心电图P波最大时限(Pmax)、P波最小时限(Pmin),计算P波离散度(Pdisp),并进行比较分析.结果 阵发性房颤组与对照组比较,P波最大时限分别为(122.22±8.70)mm和(103.24±11.18)mm31,P波最小时限分别为(71.11±7.43)mm和(64.51±10.25)mm,P波离散度分别为(50.79±6.30)mm和(38.31±5.85)mm,两组间比较有统计学意义(P＜0.001).结论 P波离散度为预测冠脉搭桥术后阵发性心房颤动的一个体表心电图的可靠指标.     

快速心房刺激对P波时限及离散度的影响

目的分析快速心房刺激对P波时限及离散度的影响.方法在74例射频消融术及82例经食管心房调搏检查中,用180ppm的S1S1刺激心房3min,在刺激前后立刻记录12导联同步心电图,通过心电图测出刺激前后的最大P波时限、最小P波时限及P波离散度,然后进行比较.结果射频消融组最大P波时限在心房刺激后比刺激前有显著性延长（p=0.002）,最小P波时限及P波离散度无显著性差异,食管心房调搏组最大P波时限及P波离散度在心房刺激后比刺激前有显著性增加（p=0.001）,最小P波时限无显著性差异.结论快速心房刺激能引起心房传导时间延长,非均质电活动的离散程度增加.最大P波时限及P波离散度是可以用来评价心房电重构的简便而无创的指标.     

P波离散度和最大时限与左心房扩大的相关性研究

目的利用同步12导联心电图和超声心动图探讨P波离散度和P波最大时限与左心房扩大的关系。方法超声心动图检测左心房扩大69例作为观察组,无左心房扩大50例作为对照组,均进行同步12导联心电图检测。结果观察组与对照组比较,P波离散度和P波最大时限均有显著增大(P0.05)。结论 P波离散度和P波最大时限对左心房扩大具有一定的诊断价值。     

The role of P wave in prediction of atrial fibrillation after coronary artery surgery

Atrial fibrillation (AF) is a common arrhythmia after coronary artery bypass surgery (CABG). The purpose of this study was to determine the role of P wave duration, amplitude and dispersion in the prediction of AF after CABG. This study included 120 patients undergoing elective CABG. Clinical characteristics, 12-lead electrocardiogram (ECG), echocardiogram and coronary angiogram were obtained in all patients. We measured P wave duration, amplitude and dispersion from 12-lead ECG in each patient. After CABG, all patients were continuously monitored for AF attacks in the intensive care unit and ordinary ward. Our results showed that age greater than 60 years was the strongest predictor of postoperative AF (p<0.01), with a 3.7-fold greater likelihood of developing postoperative AF compared to ages less than 60 years. Gender was another independent predictor of postoperative AF, with men being 3.0 times more likely to develop postoperative AF compared to women (p = 0.03). The presence of prolonged P wave duration (> or =100 ms in lead II) was also an independent predictor (p = 0.04), with 2.9-fold greater risk of developing postoperative AF compared to a P wave duration of less than 100 ms. The P wave dispersion was similar between patients with and without postoperative AF (29+/-15 vs. 33+/-15 mm, p = NS). In conclusion, old age, male gender and prolonged P wave duration were independent predictors of AF after CABG. However, P wave dispersion and amplitude did not provide significant information in the prediction of postoperative AF.     

Left Volume Atrial Index and P-wave Dispersion as Predictors of Postoperative Atrial Fibrillation After Coronary Artery Bypass Graft: A Retrospective Cohort Study

Preoperative left atrial remodeling as Postoperative atrial fibrillation (POAF) predisposing factors could be measured by left atrial volume index (LAVI) and P-wave dispersion. This study aimed to assess P-wave dispersion and LAVI as preoperative predictors of POAF among patients who underwent Coronary Artery Bypass Graft (CABG). An analytical retrospective cohort study was performed on patients who underwent CABG. The P-wave dispersion and POAF were evaluated based on documented ECG results. LAVI size was collected from echocardiographic reports. Hazard ratios of P-wave dispersion and LAVI for POAF were analyzed using Cox proportional hazard model. A total of 42 subjects (57 ± 1 years) were included in this study. POAF occurred in 28.6% of patients at a median of 2 days after CABG. P-wave dispersion was significantly longer in patients in whom AF was developed (53.03 ± 3.82 ms vs 44.01 ± 1.98ms, p:0.028), while LAVI difference was not significant. The Cox proportional hazard model showed a significant association between P-wave dispersion and risk of POAF (HR 1.05, CI95%, 1.001-1.103; P = 0.048). There was no association between LAVI and risk of POAF (HR 1.003, CI 95%, 0.965-1.044; P = 0.864). P-wave dispersion is a predictor of POAF in patients who underwent CABG. Risk stratification using P-wave dispersion enables clinicians to identify high-risk patients before CABG surgery.     

Predictive value of total atrial conduction time measured with tissue Doppler imaging for postoperative atrial fibrillation after coronary artery bypass surgery

Objective

Postoperative atrial fibrillation (POAF) complicating coronary artery bypass grafting surgery (CABG) increases morbidity and stroke risk. Total atrial conduction time (PA-TDI duration) has been identified as an independent predictor of new-onset atrial fibrillation (AF). We aimed to assess whether PA-TDI duration is a predictor of AF after CABG.

Methods

In 128 patients who had undergone CABG, preoperative clinical and echocardiographic data were compared between patients with and without POAF. The PA-TDI duration was assessed by measuring the time interval between the beginning of the P wave on the surface ECG and point of the peak A wave on TDI from left atrium (LA) lateral wall just over the mitral annulus.

Results

Patients with POAF (38/128, 29.6 %) were older (68.1?±?11.1 vs. 59.3?±?10.2 years; p?<?0.001), had higher LA maximum volume, had prolonged PA-TDI duration, and had lower ejection fraction compared with patients without POAF. PA-TDI duration was found to be significantly increased in POAF group (134.3?±?19.7 vs. 112.5?±?17.7 ms; p?=?0.01). On multivariate analysis, age (95 % CI?=?1.03–1.09; p?=?0.003), LA maximum volume (95 % CI?=?1.01–1.06; p?=?0.03), and prolonged PA-TDI duration (95 % CI, 1.02–1.05; p?=?0.001) were found to be the independent risk factors of POAF.

Conclusions

In this study, LA maximum volume and PA-TDI duration were found to be the independent predictors of the development of POAF after CABG. Echocardiographic predictors of left atrial electromechanical dysfunction may be useful in risk stratifying of patients in terms of POAF development after CABG.     

P wave dispersion and left atrial appendage function for predicting recurrence after conversion of atrial fibrillation and relation of p wave dispersion to appendage function

BACKGROUND: We investigated P wave dispersion and left atrial appendage (LAA) function for predicting atrial fibrillation (AF) relapse, and the relationship between P wave dispersion and LAA function. METHODS: Sixty-four consecutive patients with AF lasting /=5 days, LA size >/=45 mm, maximum P wave duration >/=112 ms, P wave dispersion >/=47 ms, spontaneous echo contrast, minimum LAA area >/=166 mm(2), and LAA emptying velocity <36 cm/sec were univariate predictors of recurrence (each P < 0.05). By multivariate analysis, LA size (P = 0.02), P wave dispersion (P < 0.001), and LAA emptying flow (P = 0.01) identified patients with recurrent AF. Their positive predictive values were 91, 97, and 72%, respectively. CONCLUSION: The increased P wave dispersion in addition to the dilated LA and the depressed LAA emptying flow can identify patients at risk of recurrent AF after cardioversion.     

The Value of P Dispersion on Predicting Atrial Fibrillation After Coronary Artery Bypass Surgery: Effect of Magnesium on P Dispersion

Background: AF is a frequent arrhythmia complicating CABG, and it is well known that dispersion and prolongation of P wave increases the risk of AF. The aim of this study was to investigate the effect of magnesium (Mg) treatment on P‐wave duration and dispersion in patients undergoing CABG. Method: The study included 148 consecutive patients (33 women, 115 men; mean age 62.1 ± 7.0 years) undergoing CABG who were randomly allocated to two groups. Group A consisted of 93 patients to whom 1.5 g daily MgSO₄ infusion was applied the day before surgery, just after operation, and 4 days following surgery, and group B consisted of 55 control patients. From the preoperative and postoperative fourth day, 12‐lead ECG recordings, duration of the P waves, and P‐wave dispersions were calculated. Results: There were no differences between the two groups with regard to age, sex, and blood Mg level. Comparison of the baseline and day 4 ECG measurements showed no difference as far as heart rates, duration of PQ, and QRS intervals were concerned. AF developed in 2 (2%) cases in group A and in 20 (36%) cases in group B (P < 0.001). There was no difference between the two groups when average basal P max, P min, P dispersion, and day 4 P min values were compared. In group A, fourth day P max (94.3 ± 11.8 vs 101.0 ± 13.2 ms; P = 0.0025) and P dispersion (38.2 ± 9.2 vs 44.9 ± 10.9 ms; P = 0.0002) were significantly lower as compared to group B. Comparing the patients who developed AF, and who did not, no difference was detected with regard to baseline P max, P min, P dispersion, and day 4 P min. Day 4 P max (95.1 ± 11.8 vs 106.4 ± 14.0 ms, P = 0.0015) and P dispersion (38.9 ± 8.8 vs 50.7 ± 13.0 ms, P = 0.001) of patients who developed AF were significantly higher. Baseline Mg levels were similar in patients who developed AF, and who did not, but the day 4 Mg level was significantly lower in AF group (2.0 ± 0.23 vs 2.15 ± 0.26 mg/dL, P < 0.001). Conclusion: Perioperative Mg treatment reduces P dispersion and the risk of developing AF in patients undergoing CABG. A.N.E. 2002;7(3):211–218     

Atrial fibrillation after coronary artery bypass surgery: P wave signal averaged ECG, clinical and angiographic variables in risk assessment.

BACKGROUND: Atrial fibrillation (AF) is a commonly encountered arrhythmia and occurs in up to 40% of patients after coronary artery bypass surgery (CABG). The preoperative signal averaged ECG (SAECG) P wave may be useful indicator of AF after CABG. We prospectively analyzed the predictive value of SAECG P wave compared to clinical variables. METHODS: Fifty-three patients with coronary artery disease undergoing first elective CABG were enrolled. All patients had P wave specific SAECG, standard 12 lead ECG, ejection fraction and left atrial posteroanterior diameter from the echocardiogram within the 24 h before surgery. From the SAECG P wave, filtered P wave duration was measured. Lead II P wave duration, left atrial enlargement and left ventricular hypertrophy were determined from standard ECG. Patients were continuously monitored during their postoperative period and serial ECGs were taken. RESULTS: During an observation period of up to 16 days, 19 (35.8%) patients developed AF 2.8+/-1.3 days after CABG. Patients with AF more often had left atrial enlargement (LAE) on ECG (P = 0.041) and right coronary artery (RCA) lesion (P = 0.0034). The filtered P wave duration on the SAECG was significantly longer in the AF patients than those without AF (129.7+/-13.2 ms versus 113.9+/-9.0 ms, P = 0.001). Logistic regression analysis identified independent predictors, estimated adjusted relative risk (95% confidence interval) of AF: with LAE, the relative risk was 2.72 (1.13-5.82), RCA lesion, the relative risk was 3.06 (1.45-6.45) and SAECG P wave duration >122.3 ms, the relative risk was 4.58 (2.11-9.97). The occurrence of AF was predicted by electrocardiographically determined left atrial enlargement with a sensitivity of 36%, specificity of 88%, positive predictive accuracy of 63%, negative predictive accuracy of 71%. If presence of right coronary artery lesion was evaluated these values were 63%, 79%, 63%, 79% subsequently. P wave duration >122.3 ms had a sensitivity of 68%, specificity of 88%, positive predictive accuracy of 76%, negative predictive accuracy of 83%. If both P wave >122.3 ms and presence of right coronary artery lesion were combined, these values were 47%, 94%, 81%, 76% subsequently. CONCLUSION: The predictors of AF after CABG were left atrial enlargement on standard 12 lead ECG, RCA lesion and SAECG P wave duration. Among these predictors, SAECG P wave duration was the best predictor of AF after CABG.     

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

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

P‐Wave Dispersion: A Novel Predictor of Paroxysmal Atrial Fibrillation

Background: The prolongation of intraatrial and interatrial conduction time and the inhomogeneous propagation of sinus impulses are well known electrophysiologic characteristics in patients with paroxysmal atrial fibrillation (AF). Previous studies have demonstrated that individuals with a clinical history of paroxysmal AF show a significantly increased P‐wave duration in 12‐lead surface electrocardiograms (ECG) and signal‐averaged ECG recordings. Methods: The inhomogeneous and discontinuous atrial conduction in patients with paroxysmal AF has recently been studied with a new ECG index, P‐wave dispersion. P‐wave dispersion is defined as the difference between the longest and the shortest P‐wave duration recorded from multiple different surface ECG leads. Up to now the most extensive clinical evaluation of P‐wave dispersion has been performed in the assessment of the risk for AF in patients without apparent heart disease, in hypertensives, in patients with coronary artery disease and in patients undergoing coronary artery bypass surgery. P‐wave dispersion has proven to be a sensitive and specific ECG predictor of AF in the various clinical settings. However, no electrophysiologic study has proven up to now the suspected relationship between the dispersion in the atrial conduction times and P‐wave dispersion. The methodology used for the calculation of P‐wave dispersion is not standardized and more efforts to improve the reliability and reproducibility of P‐wave dispersion measurements are needed. Conclusions: P‐wave dispersion constitutes a recent contribution to the field of noninvasive electrocardiology and seems to be quite promising in the field of AF prediction. A.N.E. 2001;6(2):159–165     

Clinical prediction rule for atrial fibrillation after coronary artery bypass grafting

OBJECTIVES: This study was designed to devise and validate a practical prediction rule for atrial fibrillation/atrial flutter (AF) after coronary artery bypass grafting (CABG) using easily available clinical and standard electrocardiographic (ECG) criteria. BACKGROUND: Reported prediction rules for postoperative AF have suffered from inconsistent results and controversy surrounding the added predictive value of a prolonged P-wave duration. METHODS: In 1,851 consecutive patients undergoing CABG with cardiopulmonary bypass, preoperative clinical characteristics and standard 12-lead ECG data were examined. Patients were continuously monitored for the occurrence of sustained postoperative AF while hospitalized. Multiple logistic regression was used to determine significant predictors of AF and to develop a prediction rule that was evaluated through jackknifing. RESULTS: Atrial fibrillation occurred in 508 of 1,553 patients (33%). Multivariate analysis showed that greater age (odds ratio [OR] 1.1 per year [95% confidence intervals (CI) 1.0 to 1.1], p < 0.0001), prior history of AF (OR 3.7 [95% CI 2.3 to 6.0], p < 0.0001), P-wave duration >110 ms (OR 1.3 [95% CI 1.1 to 1.7], p = 0.02), and postoperative low cardiac output (OR 3.0 [95% CI 1.7 to 5.2], p = 0.0001) were independently associated with AF risk. Using the prediction rule we defined three risk categories for AF: <60 points, 61 of 446 (14%); 60 to 79 points, 330 of 908 (36%); and >or=80 points, 117 of 199 (59%). The area under the receiver-operator characteristic curve for the model was 0.69. CONCLUSIONS: These data show that post-CABG AF can be predicted with moderate accuracy using easily available patient characteristics and may prove useful in prognostic and risk stratification of patients after CABG. The presence of intraatrial conduction delay on ECG contributed least to the prediction model.