Number Of Premature Atrial Complexes Research Articles

ИЗМЕНЕНИЕ ЛИПИДНОГО ПРОФИЛЯ ПЛАЗМЫ КРОВИ, ПАРАМЕТРОВ ХОЛТЕРОВСКОГО МОНИТОРИРОВАНИЯ И ЭХОКАРДИОГРАФИИ У ПАЦИЕНТОВ С ИШЕМИЧЕСКОЙ БОЛЕЗНЬЮ СЕРДЦА И ГИПОТИРЕОЗОМ

The article presents the results of a study of changes in the lipid spectrum of the blood plasma and certain indicators of Holter monitoring and echocardiography data in patients with coronary heart disease (CHD) and hypothyroidism who were in a cardiology hospital. The incidence of hypothyroidism in cardiac patients was 2.8 %. In patients with ischemic heart disease and hypothyroidism, no reliable correlation has been established between the presence of hypothyroidism and dyslipidemia, but a high incidence of hypercholesterolemia and increased levels of low-density lipoprotein cholesterol was found in patients with ischemic heart disease in combination with hypothyroidism, as in the control group. Extrasystole was determined in all patients with coronary artery disease, regardless of the presence of hypothyroidism. Only 2.7 % of patients with coronary artery disease and hypothyroidism had a decrease in myocardial contractile function according to the assessment of left ventricular ejection fraction (EF). The detection rate of left ventricular hypertrophy (LVH) in patients with coronary artery disease and hypothyroidism was 83.7 %. There was a significantly significant moderate correlation in the group of patients with coronary artery disease, regardless of the presence of hypothyroidism, between the number of premature atrial complexes (PAC) and the number of premature ventricular complexes (PVC). There was no effect of TSH level on EF values and the presence of LVH in patients with coronary artery disease in combination with hypothyroidism and in the absence of the latter.

Can 24 h of ambulatory ECG be used to triage patients to extended monitoring?

Access to long-term ambulatory recording to detect atrial fibrillation (AF) is limited for economical and practical reasons. We aimed to determine whether 24 h ECG (24hECG) data can predict AF detection on extended cardiac monitoring. We included all US patients from 2020, aged 17-100 years, who were monitored for 2-30 days using the PocketECG device (MEDICALgorithmics), without AF ≥30 s on the first day (n = 18,220, mean age 64.4 years, 42.4% male). The population was randomly split into equal training and testing datasets. A Lasso model was used to predict AF episodes ≥30 s occurring on days 2-30. The final model included maximum heart rate, number of premature atrial complexes (PACs), fastest rate during PAC couplets and triplets, fastest rate during premature ventricular couplets and number of ventricular tachycardia runs ≥4 beats, and had good discrimination (ROC statistic 0.7497, 95% CI 0.7336-0.7659) in the testing dataset. Inclusion of age and sex did not improve discrimination. A model based only on age and sex had substantially poorer discrimination, ROC statistic 0.6542 (95% CI 0.6364-0.6720). The prevalence of observed AF in the testing dataset increased by quintile of predicted risk: 0.4% in Q1, 2.7% in Q2, 6.2% in Q3, 11.4% in Q4, and 15.9% in Q5. In Q1, the negative predictive value for AF was 99.6%. By using 24hECG data, long-term monitoring for AF can safely be avoided in 20% of an unselected patient population whereas an overall risk of 9% in the remaining 80% of the population warrants repeated or extended monitoring.

Major impact of left auricular cardiopathy when associated to supraventricular ectopy?

Abstract Funding Acknowledgements Type of funding sources: None. INTRODUCTION Left atrial cardiopathy (LAC) is an independent predictor of atrial fibrillation (FA) and embolic stroke. It is more frequent in patients with embolic stroke of undetermined source (ESUS) than in non-embolic strokes. The current definition doesn’t include supraventricular ectopy. AIM The aim of this work was to describe the importance of LAC in ESUS and to study the impact of adding the number of atrial premature complexes per hour (APC/h) to LAC criteria. METHODS Retrospective analysis of 123 ESUS patients (pts) admitted to Neurology service from 2014 to 2019. LAC was defined according to two criteria (LAC2: severe left atrial enlargement or p-wave terminal force in lead V1 [PTFV1] >5000 µV*ms) or 3 criteria (LAC3: additionally, >30 APC/h). Survival analysis for the occurrence of AF, stroke recurrence and death according to LAC2 and LAC3. Diagnostic test performance analysis for each criterion with ROC curves. RESULTS 43 (35%) of the ESUS pts had LAC2. Pts with LAC2 (35.0%) were older (p = 0.007), more frequently had hypertension (p = 0.004) and lower total cholesterol levels (p = 0.044) than patients without LAC2. The incidence of AF (median follow-up 21 months, IQR = 9-35) was higher both in LAC2 (p = 0.038) and LAC3 (p = 0.001). There were no differences in stroke recurrence or death between patients with or without LAC2 or 3. Among the 3 atrial dysfunction criteria included in LAC3 definition, the number of APC/h was associated with a higher area under the curve for the occurrence of AF (AUC = 0.822). Cox regression revealed that PTFV1 > 5000 µV·ms (HR = 5.12, IC95%=1.28-20.56, p = 0.021) and >30 APC/h (HR = 13.02, IC95%=3.57-47.56) were independent predictors of AF. In addition, the single predictor of the composite endpoint (occurrence of AF, stroke recurrence and death) was >30 APC/h (HR = 5.2, p < 0,001). CONCLUSION In ESUS pts, the subgroup with LAC2 had different clinical characteristics and a higher AF incidence. APC/h were also independently associated with AF incidence and had better diagnostic test performance than the other criteria. In sum, APC/h inclusion as a diagnostic criterion for LAC should be considered and may help in a better therapeutic approach.

Predictive value of premature atrial complex characteristics in pulmonary vein isolation for patients with paroxysmal atrial fibrillation

Premature atrial complexes from pulmonary veins are the main triggers for atrial fibrillation in the early stages. Thus, pulmonary vein isolation is the cornerstone of catheter ablation for paroxysmal atrial fibrillation. However, the success rate remains perfectible. To assess whether premature atrial complex characteristics before catheter ablation can predict pulmonary vein isolation success in paroxysmal atrial fibrillation. We investigated consecutive patients who underwent catheter ablation for paroxysmal atrial fibrillation from January 2013 to April 2017 in two French centres. Patients were included if they were treated with pulmonary vein isolation alone, and had 24-hour Holter electrocardiogram data before catheter ablation available and a follow-up of≥6 months. Catheter ablation success was defined as freedom from any sustained atrial arrhythmia recurrence after a 3-month blanking period following catheter ablation. One hundred and three patients were included; all had an acute successful pulmonary vein isolation procedure, and 34 (33%) had atrial arrhythmia recurrences during a mean follow-up of 30±15 months (group 1). Patients in group 1 presented a longer history of atrial fibrillation (71.9±65.8 vs. 42.9±48.4 months; P=0.008) compared with those who were "free from arrhythmia" (group 2). Importantly, the daily number of premature atrial complexes before catheter ablation was significantly lower in group 1 (498±1413 vs. 1493±3366 in group 2; P=0.028). A daily premature atrial complex cut-off number of<670 predicted recurrences after pulmonary vein isolation (41.1% vs. 13.3%; sensitivity 88.2%; specificity 37.7%; area under the curve 0.635; P=0.017), and was the only independent predictive criterion in the multivariable analysis (4-fold increased risk). Preprocedural premature atrial complex analysis on 24-hour Holter electrocardiogram in paroxysmal atrial fibrillation may improve patient selection for pulmonary vein isolation.

Intramuscular Diphenhydramine Does Not Affect Acute Doxorubicin Infusion-Related Arrhythmia Number or Severity in a Prospective Crossover Study in Canine Lymphoma: A Pilot Study.

Background: Doxorubicin (DOX) is one of the most effective chemotherapeutics for canine high-grade lymphoma. In addition to dose-dependent chronic cardiotoxicity, DOX can trigger acute cardiac arrhythmias during drug infusion. Diphenhydramine premedication is commonly used, as histamine release is a proposed mechanism for DOX-associated arrhythmogenesis.Hypothesis/Objectives: The study objectives were to evaluate the incidence and severity of DOX infusion-related cardiac arrhythmias in dogs with high-grade lymphoma and evaluate the effect of diphenhydramine premedication on arrhythmia frequency and severity during and after DOX infusion.Animals: Twenty-two client-owned dogs with cytologically/histopathologically confirmed high-grade lymphoma were recruited, of which 19 were enrolled and 9 completed the study.Methods: Dogs were screened by echocardiogram and concurrent electrocardiogram for this randomized prospective crossover study. Group A received no premedication for DOX #1 and was premedicated with diphenhydramine for DOX #2; Group B received diphenhydramine with DOX #1 and no premedication for DOX #2. For both visits, Holter monitor data were collected for 1 h pre-DOX and 3 h post-DOX administration.Results: Nineteen dogs were enrolled and 9 dogs [Group A (5), Group B (4)] completed the protocol. There was no statistical difference between the DOX alone and DOX + diphenhydramine when evaluating the total number of ventricular premature complexes (VPCs, P = 0.34), change in VPCs/hour (P = 0.25), total number of atrial premature complexes (APCs, P = 0.5), change in APCs/hour (P = 0.06), or ventricular arrhythmia severity score (P > 0.99).Conclusions and clinical importance: This study demonstrates that in these dogs with rigorous pretreatment cardiovascular screening, DOX infusion did not induce significant arrhythmias. Furthermore, these data suggest that, with this screening approach, diphenhydramine may not alter the arrhythmia number or severity in canine DOX recipients.

Effects of Prolonged Spaceflight on Atrial Size, Atrial Electrophysiology, and Risk of Atrial Fibrillation.

The prevalence of atrial fibrillation (AF) in active astronauts is ≈5%, similar to the general population but at a younger age. Risk factors for AF include left atrial enlargement, increased number of premature atrial complexes, and certain parameters on signal-averaged electrocardiography, such as P-wave duration, root mean square voltage for the terminal 20 ms of the signal-averaged P wave, and P-wave amplitude. We aimed to evaluate changes in atrial structure, supraventricular beats, and atrial electrophysiology to determine whether spaceflight could increase the risk of AF. Thirteen astronauts underwent cardiac magnetic resonance imaging to assess atrial structure and function before and after 6 months in space and high-resolution Holter monitoring for multiple 48-hour time periods before flight, during flight, and on landing day. Left atrial volume transiently increased after 6 months in space (12±18 mL; P=0.03) without changing atrial function. Right atrial size remained unchanged. No changes in supraventricular beats were noted. One astronaut had a large increase in supraventricular ectopic beats but none developed AF. Filtered P-wave duration did not change over time, but root mean square voltage for the terminal 20 ms decreased on all fight days except landing day. No changes in P-wave amplitude were seen in leads II or V1 except landing day for lead V1. Six months of spaceflight may be sufficient to cause transient changes in left atrial structure and atrial electrophysiology that increase the risk of AF. However, there was no definite evidence of increased supraventricular arrhythmias and no identified episodes of AF.

Atrial Ectopic Activity in Cryptogenic Ischemic Stroke and TIA: A Risk Factor for Recurrence

To characterize atrial ectopic activity in patients with cryptogenic ischemic stroke (CIS) or transient ischemic attack (TIA) and determine its prognostic significance. Retrospective cohort study, in which 184 patients with CIS or TIA who had performed 24-hour Holter electrocardiogram were included. The median follow-up was 27.5 months. Baseline clinical and imagiologic characteristics, etiologic investigation results, and ischemic stroke and TIA recurrences information were collected. Number of atrial premature complexes (APCs) per hour was categorized as less than 10 APCs/hour, 10-30 APCs/hour, and more than 30 APCs/hour. Most of the patients had less than 10 APCs/hour (82.6%), 8.2% had 10-30 APCs/hour, and 9.2% had more than 30 APCs/hour. Patients with more than 30 APCs/hour had a greater median left atrium diameter than patients with 30 APCs/hour or less (42 mm vs. 38 mm; 95% confidence interval [CI], .50-7.00; P = .003). Annual recurrence rate of CIS or TIA was 2.9% in patients with less than 10 APCs/hour, 11.0% in 10-30 APCs/hour, and 22.6% in more than 30 APCs/hour (P = .001). More than 30 APCs/hour were independently associated with recurrence risk in multivariate survival analysis (hazard ratio, 3.40; 95% CI, 1.12-10.32; P = .030). In patients with CIS or TIA, frequent atrial ectopic activity (>30 APCs/h) was independently associated with increased risk of stroke or TIA recurrence. Further studies need to validate frequent atrial ectopic activity as a risk factor for recurrence in cryptogenic stroke and confirm its role as a predictor of occult atrial fibrillation.

Frequent premature atrial complexes… truly a benign finding? Author reply

We thank Dr Sergio Barra for his comments1 on our recent observation of the association between frequent premature atrial complexes (PACs) and new-onset atrial fibrillation (AF) and ischaemic stroke in symptomatic patients published in the Journal.2 We generally agree with Dr Barra's comment that rapid runs of PACs at least mechanistically would be a better surrogate marker for AF than absolute number of PACs. While conceptually attractive, the use of rapid runs of PACs as a marker for AF could present clinical difficulty because of its heterogeneity and complexity. Specifically, the quantification of runs of PACs include parameters that include number of runs …

Frequent premature atrial complexes predict new occurrence of atrial fibrillation and adverse cardiovascular events

To investigate the relation between baseline frequency of premature atrial complexes (PACs) and new atrial fibrillation (AF) and adverse cardiovascular events. Four hundred and twenty-eight patients without AF or structural heart disease undergoing 24 h electrocardiography monitoring for palpitations, dizziness, or syncope were recruited. One hundred and seven patients with number of PACs at the top quartile (i.e. > 100PACs/day) were defined to have frequent PACs. After 6.1-year follow-up, 31 patients (29%) with frequent PACs developed AF compared with 29 patients (9%) with PACs ≤ 100/day (P< 0.01). Cox regression analysis revealed that frequent PACs [hazard ratio (HR): 3.22 (95% confidence interval (CI): 1.9-5.5; P< 0.001)], age >75 years (HR: 2.3; 95% CI: 1.3-3.9; P= 0.004), and coronary artery disease (HR: 2.5; 95% CI: 1.4-4.4; P= 0.002) were independent predictors for new AF. Concerning the composite endpoint (ischaemic stroke, heart failure, and death), patients with frequent PACs were more at risk than those without (34.5 vs. 19.3%) (HR: 1.95; 95% CI: 1.37-3.50; P= 0.001). Cox regression analysis showed that age >75 years (HR: 2.2; 95% CI: 1.47-3.41; P< 0.001), coronary artery disease (HR: 2.2, 95% CI: 1.42-3.44, P< 0.001), and frequent PACs (HR: 1.6; 95% CI: 1.04-2.44; P= 0.03) were independent predictors for the secondary composite endpoint. Frequent PACs predict new AF and adverse cardiovascular events.

Extended Electrocardiographic Poincare Analysis (EPA) for Better Identification of Patients with Paroxysmal Atrial Fibrillation

Background: Atrial fibrillation (AF) – be it permanent or paroxysmal – is the most frequent and most effectively treatable cause of stroke. However, when paroxysmal, even electrocardiography for 24 hours (24h-ECG) misses AF in more than 50% of cases. We assessed whether extended Poincare analysis of ECG R-R intervals (EPA) can help to identify electrocardiographic remodeling suggestive of paroxysmal AF (PAF). Methods: Twenty-nine patients with previously diagnosed PAF were re-assessed by 24h-ECG using conventional analysis and EPA based on a previously trained algorithm considering among other ratios of R-R interval duration, number of premature atrial complexes, approximate entropy, and standard deviation of Poincare plots-axes. 24h-ECG from 21 healthy subjects without a history of AF served as negative, and 9 patients with permanent AF as positive controls. Results: PAF during 24h-ECG was detected in 4 out of 29 (14%) patients with a history of PAF by conventional analysis. EPA classified ECGs of these and 22 additional patients with a history of PAF, i.e. a total 90%, as suggestive of PAF. All patients with permanent AF were identified by both tools. EPA additionally classified the ECG in 4 out of 21 control subjects as suggestive of PAF. Conclusions: Extended Poincare analysis in patients with a history of PAF is more sensitive to electrocardiographic abnormalities than is conventional 24h- ECG analysis. These findings warrant prospective studies of EPA in patients with a high likelihood of PAF, i.e. with stroke of undetermined origin.

Advanced pacemaker diagnostic features in the characterization of atrial fibrillation: impact on preventive pacing algorithms.

Pacing algorithms to prevent PAF are mainly based on the suppression of premature atrial complexes (PACs), which play an important role in its initiation. In contrast to 24-hour ambulatory electrocardiograms, advanced pacemaker (PM) diagnostic features are capable of recording AF episodes during long follow-up periods and of characterizing AF in a detailed fashion. For the specific use of these algorithms, a detailed characterization of AF was performed in 91 dual chamber PM recipients with histories of AF. Fifteen patients with episodes of oversensing due to far-field signals or frequent episodes of "2:1-undersensing" of atrial flutter were excluded. The remaining 76 patients had high recurrence rates of AF (median 0.8 episodes/day), however, the majority of episodes lasted < 7 minutes. Despite frequent PACs (median 10.8/hour) during sinus rhythm, a median of 66.4% of the AF episodes were preceded by < 2 PACs/min before onset. In conclusion, frequent, short-lived AF episodes seem best suited for AF preventive pacing therapies. However, the small number of PACs preceding many AF episodes may limit the efficacy of PAC suppressing algorithms.

The Prognostic Significance of Atrial Arrhythmias Recorded Early After Cardioversion for Atrial Fibrillation

In a substantial number of patients, AF recurs after successful electrical cardioversion. The purpose of this study was to investigate if the atrial arrhythmias recorded immediately after cardioversion are associated with the risk of recurrence of the arrhythmia and to compare the prognostic significance of this parameter with that of other established risk factors. In a series of 71 patients, the risk factors for recurrence of AF during the first year after successful electrical cardioversion were analyzed. A new parameter that was investigated was the frequency of atrial premature beats and the presence of runs of supraventricular tachycardia in the Holter recording started immediately after the cardioversion. Age, left atrial size, left ventricular systolic function, duration of the arrhythmia before cardioversion, underlying cardiac disease, or medication taken were not found to be predictive of recurrence of the arrhythmia. However, the natural logarithm of the number of atrial premature complexes per hour of the Holter recording in the 37 patients in whom AF recurred was higher compared to that of the 34 patients who maintained sinus rhythm (P < 0.0005). The same was true if only the first 6 hours of the recording were analyzed (P < 0.0005). There was a trend for more frequent arrhythmia recurrence if runs of supraventricular tachycardia were present. The finding of > 10 atrial premature complexes per hour in the recording had a relative risk of 2.57 (1.51-4.37), a positive predictive accuracy of 76.5%, and a negative predictive accuracy of 70.3% for subsequent arrhythmia recurrence. We can conclude that frequent (> 10/hour) atrial premature complexes in the Holter recording after electrical cardioversion for AF is a significant risk factor for recurrence of the arrhythmia.

Impact of consistent atrial pacing algorithm on premature atrial complexe number and paroxysmal atrial fibrillation recurrences in brady-tachy syndrome: a randomized prospective cross over study.

The Consistent Atrial Pacing (CAP) algorithm has been designed to achieve a high percentage of atrial pacing to suppress paroxysmal atrial fibrillation. The aim of our study was to compare the impact of DDDR+CAP versus DDDR pacing on paroxysmal atrial fibrillation recurrences and triggers in patients with Brady-Tachy Syndrome. 61 patients, 23 M and 38 F, mean age 75+/-9 y, affected by Brady-Tachy Syndrome, implanted with a DDDR pacemaker, were randomized to DDDR or DDDR+CAP pacing with cross over of pacing modality after 1 month. 78 % of patients in DDDR pacing and 73 % in DDDR + CAP pacing (p=n.s.) were free from symptomatic paroxysmal atrial fibrillation recurrences. During DDDR+CAP pacing, the atrial pacing percentage increased from 77+/-29 % to 96+/-7 % (p<0.0001). Automatic mode switch episodes/day were 0.73+/-1.09 in DDDR and 0.79+/-1.14 (p=n.s.) in DDDR+CAP. In patients with less than 50 % of atrial pacing during DDDR, automaticmode switch episodes/day decreased during DDDR+CAP from 1.13+/-1.59 to 0.23+/-0.32 (p<0.05) and in patients with less than 90 % from 1.23+/-1.27 to 0.75+/-1.10 (p<0.001). The number of premature atrial complexes per day decreased during DDDR + CAP from 2665+/-4468 to 556+/-704 (p<0.02). CAP algorithm allowed continuous overdrive atrial pacing without major side effects. Triggers of paroxysmal atrial fibrillation induction, such as premature atrial complexes, were critically decreased. Paroxysmal atrial fibrillation episodes were reduced in patients with atrial pacing percentage lower than 90 % during DDDR pacing.

Variations of autonomic tone preceding onset of atrial fibrillation after coronary artery bypass grafting

Assessment of autonomic tone preceding the onset of atrial fibrillation (AF) after coronary artery bypass grafting (CABG) with heart rate variability was examined in 64 patients scheduled for elective CABG (days 2 to 5). Ninety-six-hour Holter tapes were analyzed in each patient and all events labeled by an experienced technician. The hour preceding AF was divided into 4 quarters (heart rate variability calculated per quarter) and compared with similar time episodes from the group without AF. Twenty-six of 64 patients (40%) had a total of 35 episodes. Only increased age (68 ± 5 vs 62 ± 9 years) and lower ejection fraction (66 ± 16% vs 73 ± 8%) were associated with an increased risk for AF. Before onset, a greater number of atrial premature complexes was observed. The standard deviation of all RR intervals (SDNN) showed an increase in the group with AF in the last 15 minutes (significant vs controls and within the AF group). The low-frequency/high-frequency ratio was significantly lower in patients in the first 30 minutes, followed by an increase mainly because the high-frequency spectrum became less important. Thus, initiation of postoperative AF is influenced by autonomic tone variations. A shift in the autonomic balance with a loss of vagal tone and a moderate increase in sympathetic tone are observed before the onset of AF compared with those in controls.