P-Wave Duration or P-Wave Morphology? Interatrial Block: Seeking for the Holy Grail to Predict AF Recurrence

Abstract Background Advanced interatrial block (IAB), prolonged and bimodal P waves in surface ECG inferior leads, is an unrecognized surrogate of atrial dysfunction and a trigger of atrial dysrhythmias, mainly atrial fibrillation (AF). Our aim was to prospectively assess whether advanced IAB in sinus rhythm precedes AF and stroke in elderly outpatients with structural heart disease, a group not previously studied. Methods Prospective observational registry that included outpatients aged ≥70 years with structural heart disease and no previous diagnosis of AF. Patients were divided into three groups according to P-wave characteristics. Results Among 556 individuals, 223 had normal P-wave (40.1%), 196 partial IAB (35.3%), and 137 advanced IAB (24.6%). After a median follow-up of 694 days; 93 patients (16.7%) developed AF, 30 stroke (5.4%), and 34 died (6.1%). Advanced IAB was independently associated with AF (hazard ratio [HR] 2.9, 95% confidence interval [CI] 1.7–5.1, p<0.001), stroke (HR 3.8, 95% CI 1.4–10.7, p=0.010), and AF/stroke (HR 2.6, 95% CI 1.5–4.4, p=0.001). P-wave duration (ms) was independently associated with AF (HR 1.05, 95% CI 1.03–1.07, p<0.001), AF/stroke (HR 1.04, 95% CI 1.02–1.06, p<0.001), and mortality (HR 1.04, 95% CI 1.00–1.08, p=0.021). Conclusions The presence of advanced IAB in sinus rhythm is a risk factor for AF and stroke in an elderly population with structural heart disease and no previous diagnosis of AF. P-wave duration was also associated with all-cause mortality. Figure. Age- and sex-adjusted linear and non-linear association between P-wave duration (msec) and atrial fibrillation (A), stroke (B), and atrial fibrillation or stroke (C) risk. Results of a generalized additive model with spline smoothing functions and 4 degrees of freedom. Figure 1. Kaplan-Meyer curves of survival free of atrial fibrillation (A), stroke (B) and atrial fibrillation or stroke (C) in patients with normal P-wave, partial interatrial block (IAB) and advanced IAB. Funding Acknowledgement Type of funding source: None

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Electrocardiographic markers of atrial cardiomyopathy predict ineffective cardioversion: a FinCV2 cohort study

European Heart Journal ◽

10.1093/ehjci/ehaa946.0408 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

A Relander ◽

T Hellman ◽

T Vasankari ◽

I Nuotio ◽

K.E.J Airaksinen ◽

...

Keyword(s):

Sinus Rhythm ◽

Independent Predictor ◽

P Wave ◽

University Hospital ◽

Funding Source ◽

Recurrence Rates ◽

Cardiovascular Research ◽

Wave Duration ◽

P Wave Duration ◽

Af Recurrence

Abstract Background Rhythm control using electrical cardioversion (CV) is a common treatment strategy for patients with symptomatic atrial fibrillation (AF). However, little is known about electrocardiographic (ECG) markers predicting CV failure and AF recurrence. Methods This study included 726 patients who underwent a CV for AF lasting >48h in a referral hospital. We analysed markers of atrial cardiomyopathy in post-CV sinus rhythm ECGs and compared them with CV failure and AF recurrence rates within 30 days after CV as well as their combination (ineffective CV). Of those with failed CV the most recent sinus rhythm ECG was used. Results CV was unsuccessful in 66 out of 726 patients (9.09%). Advanced interatrial block (IAB) defined as P-wave duration ≥120ms and biphasic morphology in inferior (II, III and aVF) leads (OR 3.96, 95%-CI 2.09–7.52, p<0.001) was an independent predictor for CV failure. Within 30 days after CV, AF recurred in 214 (32.4%) patients. Advanced IAB (OR 2.10, 95%-CI 1.19–3.72, p=0.011) was an independent predictor for AF recurrence. In total CV was ineffective (CV failure or AF recurrence) 280 of 726 times (38.6%). Advanced IAB (OR 2.72, 95%-CI 1.64–4.51, p<0.001) was an independent predictor for ineffective CV. Partial IAB categorized as P-wave duration ≥120ms with no biphasic morphology did not predict any end points. Conclusions Advanced IAB predicts CV inefficacy. This study identified ECG markers of atrial cardiomyopathy for clinical use in CV patient selection. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): This study research was funded by grants from the Finnish Medical Foundation, the Finnish Foundation for Cardiovascular Research, State Clinical Research Fund of Turku University Hospital, Turku, Finland, Finnish Cardiac Society, the Emil Aaltonen Foundation, and the Maud Kuistila Foundation.

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An Atrial Fibrillation with Normal Limits using Signal Processing- A Review

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i2.24.12133 ◽

2018 ◽

Vol 7 (2.24) ◽

pp. 453

Author(s):

S. Sathish ◽

K Mohanasundaram

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Normal Sinus Rhythm ◽

P Wave ◽

Wave Duration ◽

Normal Limits ◽

Normal Sinus ◽

P Wave Duration ◽

Standard Lead ◽

Wave Morphology

Atrial fibrillation is an irregular heartbeat (arrhythmia) that can lead to the stroke, blood clots, heart failure and other heart related complications. This causes the symptoms like rapid and irregular heartbeat, fluttering, shortness of breath etc. In India for every around 4000 people eight of them are suffering from Atrial Fibrillation. P-wave Morphology. Abnormality of P-wave (Atrial ECG components) seen during sinus rhythm are associated with Atrial fibrillation. P-wave duration is the best predictor of preoperative atrial fibrillation. but the small amplitudes of atrial ECG and its gradual increase from isometric line create difficulties in defining the onset of P wave in the Standard Lead Limb system (SLL).Studies shows that prolonged P-wave have duration in patients (PAF) In this Study, a Modified Lead Limb (MLL) which solves the practical difficulties in analyzing the P-ta interval for both in healthy subjects and Atrial Fibrillation patients. P-Ta wave interval and P-wave duration can be estimated with following proposed steps which is applicable for both filtered and unfiltered atrial ECG components which follows as the clinical database trials. For the same the p-wave fibrillated signals that escalates the diagnosis follows by providing minimal energy to recurrent into a normal sinus rhythm.

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Abstract 2125: P Wave Morphology Is a Predictor of Poor Cardiac Outcome and Death in MADIT II Patients

Circulation ◽

10.1161/circ.118.suppl_18.s_671 ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Fredrik Holmqvist ◽

Pyotr G Platonov ◽

Scott McNitt ◽

Slava Polonsky ◽

Jonas Carlson ◽

...

Keyword(s):

Myocardial Infarction ◽

Cardiac Death ◽

P Wave ◽

Wave Duration ◽

P Wave Duration ◽

Increased Risk ◽

All Cause Mortality ◽

Wave Morphology ◽

Cardiac Outcome ◽

Madit Ii

The objective of the present study was to non-invasively analyse atrial electrophysiology to identify markers associated with increased risk of mortality and deterioration of heart failure in a high-risk population with advanced CHF and a history of acute myocardial infarction. Patients included in MADIT II with sinus rhythm at baseline were studied (n=802). Unfiltered and bandpass filtered signal-averaged P waves were analyzed to determine orthogonal P wave morphology, P wave duration and RMS20. The association between P wave parameters and data on the clinical course and cardiac events during a mean follow-up of 20 months was analyzed. P wave duration was 139±23 ms and the RMS20 was 1.9±1.1 μV. None of these parameters were significantly associated with poor cardiac outcome. Differences in P wave morphology were independently predictive of non-sudden cardiac death (HR 2.66; 95% CI 1.41–5.04, P=0.0027). In addition, in univariate analyses differences in P wave morphology were found to be associated with an increased risk of all-cause mortality (HR 1.35; 95%CI 1.01–1.81, P=0.042) and cardiac death (HR 1.54; 95%CI 1.10 –2.16, P=0.011) (figure ) In the present study the value of analyzing the P wave morphology in patients with previous myocardial infarction and CHF is demonstrated. Changes in P wave morphology were shown to be independently predictive of increased risk of non-sudden cardiac death. Furthermore, statistically significant associations between P wave morphology changes and all-cause mortality, cardiac death and CHF hospitalization was demonstrated.

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Correlation of Left Atrial Size With P-Wave Duration in Interatrial Block

CHEST Journal ◽

10.1378/chest.128.4.2615 ◽

2005 ◽

Vol 128 (4) ◽

pp. 2615-2618 ◽

Cited By ~ 46

Author(s):

Vignendra Ariyarajah ◽

Kristin Mercado ◽

Sirin Apiyasawat ◽

Puneet Puri ◽

David H Spodick

Keyword(s):

Left Atrial ◽

P Wave ◽

Left Atrial Size ◽

Wave Duration ◽

P Wave Duration ◽

Atrial Size ◽

Interatrial Block

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Detection of inter-atrial conduction defects with unfiltered signal-averaged P-wave ECG in patients with lone atrial fibrillation

EP Europace ◽

10.1053/eupc.1999.0072 ◽

2000 ◽

Vol 2 (1) ◽

pp. 32-41 ◽

Cited By ~ 55

Author(s):

P.G. Platonov ◽

J. Carlson ◽

M.P. Ingemansson ◽

A. Roijer ◽

A. Hansson ◽

...

Keyword(s):

Atrial Fibrillation ◽

Template Matching ◽

P Wave ◽

Control Group ◽

Conduction Delay ◽

Lone Atrial Fibrillation ◽

Wave Duration ◽

P Wave Duration ◽

Surface Ecg ◽

Wave Morphology

Abstract Aims To demonstrate a possible inter-atrial conduction delay in patients with lone paroxysmal atrial fibrillation (PAF) using ‘unfiltered’ signal-averaged P-wave ECG (PSAECG) and compare these results with those obtained with conventional filter settings. Methods and Results Twenty one patients with lone PAF and 20 healthy volunteers (control group) were enrolled in the study. An orthogonal lead surface ECG was high-pass filtered at 0·8 Hz, averaged with template matching, and combined into a spatial magnitude (‘unfiltered’ technique). Results were compared with conventionally filtered (40–300 Hz) PSAECG. The filtered technique revealed no differences in P-wave duration between the two groups (121±12 vs 128±15 ms, control and PAF groups respectively, ns). Double-peaked P-wave spatial magnitudes (interpeak distance >30 ms) were revealed in 11 of 21 PAF patients but only in two of 18 controls (P<0·01). The nadir in the spatial magnitude was located significantly later in the PAF group (114±13 vs 103±9 ms,P <0·01). Conclusion ‘Unfiltered’ PSAECG revealed significant differences in orthogonal P-wave morphology in patients with lone PAF, indicating the possibility of an inter-atrial conduction delay, while conventional P-wave duration analysis failed to discriminate between the two groups.

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Baseline ECG and Prognosis After Transcatheter Aortic Valve Implantation: The Role of Interatrial Block

Journal of the American Heart Association ◽

10.1161/jaha.120.017624 ◽

2020 ◽

Vol 9 (22) ◽

Author(s):

Lourdes Vicent ◽

Clara Fernández‐Cordón ◽

Luis Nombela‐Franco ◽

Luis Alberto Escobar‐Robledo ◽

Ana Ayesta ◽

...

Keyword(s):

Atrial Fibrillation ◽

Aortic Valve ◽

Transcatheter Aortic Valve Implantation ◽

P Wave ◽

Wave Duration ◽

Transcatheter Aortic Valve ◽

P Wave Duration ◽

Aortic Valve Implantation ◽

Interatrial Block ◽

Valve Implantation

Background The clinical significance of conduction disturbances after transcatheter aortic valve implantation has been described; however, little is known about the influence of baseline ECGs in the prognosis of these patients. Our aim was to study the influence of baseline ECG parameters, including interatrial block (IAB), in the prognosis of patients treated with transcatheter aortic valve implantation. Methods and Results The BIT (Baseline Interatrial Block and Transcatheter Aortic Valve Implantation) registry included 2527 patients with aortic stenosis treated with transcatheter aortic valve implantation. A centralized analysis of baseline ECGs was performed. Patients were divided into 4 groups: normal P wave duration (<120 ms); partial IAB (P wave duration ≥120 ms, positive in the inferior leads); advanced IAB (P wave duration ≥120 ms, biphasic [+/–] morphology in the inferior leads); and nonsinus rhythm (atrial fibrillation/flutter and paced rhythm). The mean age of patients was 82.6±9.8 years and 1397 (55.3%) were women. A total of 960 patients (38.0%) had a normal P wave, 582 (23.0%) had partial IAB, 300 (11.9%) had advanced IAB, and 685 (27.1%) presented with nonsinus rhythm. Mean follow‐up duration was 465±171 days. Advanced IAB was the only independent predictor of all‐cause mortality (hazard ratio [HR], 1.48; 95% CI, 1.10–1.98 [ P =0.010]) and of the composite end point (death/stroke/new atrial fibrillation) (HR, 1.51; 95% CI, 1.17–1.94 [ P =0.001]). Conclusions Baseline ECG characteristics influence the prognosis of patients with aortic stenosis treated with transcatheter aortic valve implantation. Advanced IAB is present in about an eighth of patients and is associated with all‐cause death and the composite end point of death, stroke, and new atrial fibrillation during follow‐up.

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Optimal P-Wave Duration for Bedside Diagnosis of Interatrial Block

Annals of Noninvasive Electrocardiology ◽

10.1111/j.1542-474x.2006.00113.x ◽

2006 ◽

Vol 11 (3) ◽

pp. 259-262 ◽

Cited By ~ 13

Author(s):

Vignendra Ariyarajah ◽

Sirin Apiyasawat ◽

David H. Spodick

Keyword(s):

P Wave ◽

Wave Duration ◽

P Wave Duration ◽

Interatrial Block ◽

Bedside Diagnosis

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P3799Experimental model of interatrial block by Bachmann bundle conduction block

European Heart Journal ◽

10.1093/eurheartj/ehz745.0644 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

J M Guerra Ramos ◽

G Vilahur ◽

A Bayes De Luna ◽

L Casani ◽

J A Cabrera ◽

...

Keyword(s):

Animal Model ◽

Left Atrium ◽

Conduction Block ◽

P Wave ◽

Healthy Animal ◽

Wave Duration ◽

P Wave Duration ◽

Before And After ◽

Interatrial Block ◽

Bachmann Bundle

Abstract Background The recognition of advanced IAB is becoming an important clinical landmark due to its association with atrial fibrillation, the so-called Bayes' syndrome. The electrocardiographic (ECG) criteria of interatrial block (IAB) have been established. A P-wave duration ≥120 ms is considered partial IAB and if there is a biphasic P-wave in the inferior leads advanced IAB. The pathophysiology of this ECG finding has been largely discussed. IAB has been explained as the result of the retrograde activation of left atrium due to complete block in the Bachmann bundle (BB). Purpose To assess the ECG changes resulting of blocking BB conduction in an experimental healthy animal model. Additionally, to compare the pattern of activation of the left atrium before and after the block. Methods Six open-chest anesthetized healthy adult swine were studied. A twelve-lead ECG was continuously recorded. The BB was epicardially accessed at the traversus sinus of the pericardium. At that level, monopolar electrosurgical energy (3 animals) and radiofrequency energy (3 animals) (Boston Scientific Blazer™ II XP, 8 mm tip) was applied until extensive tissue disruption was present and permanent P-wave changes observed. An electroanatomical map CARTO® XP (Biosense Webster Inc) of the right and left atrium was performed in two animals before and after energy deployment. Finally, animals were sacrificed, and tissue samples collected for anatomopathological examination. Results After energy application, all animals showed a significant prolongation of P-wave duration from 59±11 msec to 115±13 msec (p<0.001) with appearance of a biphasic P-wave pattern in the inferior leads. The CARTO® maps showed a change in left atrial activation, cranio-caudal at baseline and caudo-cranial at the end of the procedure. (Figure) The histological analysis showed transmural lesions at the level of the BB in all the specimens. ECG/CARTO maps: Baseline and after block Conclusion IAB ECG pattern, accompanied by a marked change in the activation of the left atrium, develops after blocking the conduction at the level of the BB in an experimental healthy animal model. These results confirm the association of IAB and BB conduction block and suggest that IAB represents an independent entity. Acknowledgement/Funding Fundaciό Privada Daniel Bravo Andreu

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