Occurrence Of Paroxysmal Atrial Fibrillation Research Articles

Abstract 18768: Diagnosis of Occult Atrial Fibrillation in Patients With Embolic Stroke of an Undetermined Source Based on Left Atrial Strain

Introduction and Hypothesis: A late electrocardiographic evaluation of patients with embolic stroke of an undetermined source (ESUS) can show atrial fibrillation as a potential cause of embolic stroke. Existing literature has highlighted that left atrial dysfunction can lead to the development of paroxysmal atrial fibrillation (PAF) and subsequent embolism. Our study sought to evaluate the diagnosis of occult atrial fibrillation in patients with embolic stroke of an undetermined source based on abnormalities in the left atrial strain. Methods: 230 patients were included in our multi-center, observational study with the mean age as 56.4 years and 26% females. We followed up on these patients for the occurrence of paroxysmal atrial fibrillation and recurrent ischemic stroke. Trans thoracic echocardiography (TTE) was done, and images were subsequently analyzed for spackle tracing deformation patterns. Primary and secondary outcomes included plotting these atrial strain values against PAF and recurrent ischemia, respectively. Results: 198 patients completed the study. Patients with newly diagnosed PAF had more abnormal left atrial reservoir strain (LASr; 27.3% ± 12.2%, P<0.05) and left atrial conduit strain (LAScd; -13.7% ± 6.2%, P<0.05) compared with patients who had normal rhythm. Multivariable logistic regression analysis showed that LAScd was associated with occult PAF (adjusted odds ratio [aOR] = 1.212, 95% CI, 1.043-1.314, P<0.05) and the composite outcome of AF and recurrent ischemic stroke (OR = 1.146, 95% CI, 1.023-1.185, P<0.05). Conclusions: Our study concluded that abnormal left atrial strain is associated with the detection of occult AF in patients admitted with embolic stroke of undetermined origin. Early detection of etiology by determining left atrial strain can lead to better prognosis and good clinical outcomes.

Atrial fibrillation and ischemic heart disease: (un)solved therapeutic dilemma?

Concomitant presence of atrial fibrillation and coronary artery disease requiring percutaneous coronary intervention is a frequent occurrence. The choice of optimal antithrombotic therapy, in this context, is still challenging. To offer the best protection both in terms of stroke and stent thrombosis, triple therapy with oral anticoagulation and dual antiplatelet therapy would be required. Several drug combinations have been tested in recent years, including direct oral anticoagulants, with the aim of balancing ischemic and bleeding risk. Both pharmacokinetic aspects of the molecules and patient's characteristics should be analyzed in choosing oral anticoagulation. Then, as suggested by guidelines, triple therapy should start with a seven-day duration and the aim to prolong to thirty days in high thrombotic risk patients. Dual therapy should follow to reach twelve months after coronary intervention. Even not fully discussed by the guidelines, in order to balance ischemic and bleeding risk it should also be considered: 1) integrated assessment of coronary artery disease and procedural complexity of coronary intervention; 2) appropriateness to maintain the anticoagulant drug dosage indicated in technical data sheet; the lack of data on the suspension of antiplatelet drugs one year after percutaneous intervention; 3) the possibility of combination therapy with ticagrelor; and 4) the need to treat the occurrence of paroxysmal atrial fibrillation during acute coronary syndrome. With data provided clinician should pursue a therapy as personalized as possible, both in terms of drug choice and treatment duration, in order to balance ischemic and bleeding risk.

Increased Left Atrial Stiffness is Significantly Associated with Paroxysmal Atrial Fibrillation in Diabetic Patients.

Atrial fibrillation (AF) and diabetes mellitus (DM) are common pathogenic diseases. Diabetes is an independent risk factor for AF, and coexisting AF is a risk factor for the diabetic pa-tient's progression. The purpose of this study was to see if two-dimensional-speckle tracking echocardiography (2D-STE) might provide valuable criteria for determining the risk of AF in diabetic patients. This retrospective study compared 30 adult diabetic patients with documented paroxysmal atrial fibrillation (PAF) with 30 age- and sex-matched diabetic patients without PAF. Inclusion criteria were: age ≥18 years, sinus rhythm, diabetes mellitus type 2, and the ability to sign the informed consent. Exclusion criteria included: moderate or severe valvular disease, previous myocardial infarction, left ventricular ejection fraction (LVEF) <50%, congenital heart disease, a history of cardiac surgery, paced atrial or ventricular rhythm, inadequate echocardiography imaging. The medical history, clinical, biochemical data and the results of the transthoracic cardiac ultrasound examination were registered during their evaluation at the outpatients cardiology clinics. The mean age of the patients was 62.5±1.7 years, 60% were men. Diabetic patients who experienced PAF episodes demonstrated significantly impaired left atrial (LA) deformation patterns, with decreased LA strains and increased LA stiffness (p < 0.05). The present study demonstrates that LA strains and LA stiffness are significantly associated with the occurrence of PAF in diabetic patients. As 2D-STE of the LA is more sensitive than routine echocardiographic examination, it should be performed in patients suspected of being suffering from PAF.

New-Onset Paroxysmal Atrial Fibrillation in the Setting of Acute Pulmonary Embolism Is Associated with All-Cause Hospital Mortality in Women but Not in Men.

Patients with acute pulmonary embolism (PE) may have various types of atrial fibrillation (AF). The role of AF in hemodynamic states and outcomes may differ between men and women. In total, 1600 patients (743 males and 857 females) with acute PE were enrolled in this study. The severity of PE was assessed using the European Society of Cardiology (ESC) mortality risk model. Patients were allocated into three groups according to their electrocardiography recordings taken during hospitalization: sinus rhythm, new-onset paroxysmal AF, and persistent/permanent AF. The association between the types of AF and all-cause hospital mortality was tested using regression models and net reclassification index (NRI) and integrated discrimination index (IDI) statistics with respect to sex. There were no differences between the frequencies of the types of AF between men and women: 8.1% vs. 9.1% and 7.5% vs. 7.5% (p = 0.766) for paroxysmal and persistent/permanent AF, respectively. We found that the rates of paroxysmal AF significantly increased across the mortality risk strata in both sexes. Among the types of AF, the presence of paroxysmal AF had a predictive value for all-cause hospital mortality independent of mortality risk and age in women only (adjusted HR, 2.072; 95% CI, 1.274-3.371; p = 0.003). Adding paroxysmal AF to the ESC risk model did not improve the reclassification of patient risk for the prediction of all-cause mortality, but instead enhanced the discriminative power of the existing model in women only (NRI, not significant; IDI, 0.022 (95% CI, 0.004-0.063); p = 0.013). The occurrence of paroxysmal AF in female patients with acute PE has predictive value for all-cause hospital mortality independent of age and mortality risk.

Heart rate during sinus rhythm predicts paroxysmal atrial fibrillation on 30-day mobile cardiac telemetry monitoring

Abstract Background Low mean heart rate at ambulatory ECG monitoring and low resting heart rate are both predictors of later incident atrial fibrillation (AF). The aim of this study is to determine whether mean heart rate at ambulatory ECG is a predictor of paroxysmal AF that can be detected with extended ambulatory ECG registration. Methods We included all patients who recorded 2–30 full days of ambulatory ECG using a full disclosure mobile cardiac telemetry device in USA 2019–2020, and without AF on the first full day of registration (n=18,220, mean age 64.4 years, 57.2% women). The association between mean heart rate on the first day and the occurrence of paroxysmal AF (≥30 seconds duration) during subsequent up to 30 day ECG recording was analysed using logistic regression models adjusted for age, sex and duration of ECG recording, according to tertiles of mean heart rate (39–66, 67–76 and &amp;gt;77 beats per minute) as well as modelled using restricted cubic splines. Results During a median registration duration of 16 days there were 1,290 cases of paroxysmal AF (7.1%). More paroxysmal AF occurred in the lower tertiles of mean heart rate (11.2% in tertile 1, 6.2% in tertile 2, and 4.4% in tertile 3). After adjustment, low mean heart rate was associated with a higher risk of AF (OR 1.69, 95% CI 1.47–1.93 p&amp;lt;0.001 for tertile 1 vs tertile 2, and OR 1.84, 95% CI 1.58–2.15, p&amp;lt;0.001 for tertile 1 vs tertile 3). Cubic spline curves indicated that lowest risks of AF were seen among subjects with a mean heart rate ≈80 beats per minute. Conclusion Low mean heart rate at 24hECG predicts detection of paroxysmal AF during extended ≤30 day ambulatory ECG monitoring. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Swedish Heart Lung foundationSwedish Society for Medical Research

Manganese Superoxide Dismutase as a Novel Oxidative Stress Biomarker for Predicting Paroxysmal Atrial Fibrillation.

Background: There is accumulating evidence indicating that inflammation and oxidative stress are involved in the pathogenesis of atrial fibrillation (AF). The role of manganese superoxide dismutase (MnSOD) in the initiation and maintenance of AF has not yet been well characterized. The aim of our study is to investigate whether or not plasma MnSOD levels are associated with AF. Methods: We enrolled a total of 130 consecutive patients with AF as the case group (paroxysmal AF: 87, persistent AF: 43) and 58 patients without a history of AF as the control group after screening. Baseline clinical characteristics, laboratory and echocardiographic parameters were collected. Plasma levels of nicotinamide-adenine dinucleotide phosphate oxidase 4 (NOX4) and MnSOD were measured by an enzyme-linked immunosorbent assay (ELISA) method. These data were compared between the different groups. The relationship between MnSOD and other parameters was assessed using Spearman correlation. Multivariable logistic regression analysis was performed to identify independent predictors of AF. The area under the curve (AUC) from receiver operating characteristics (ROC) analysis was constructed to explore the value of MnSOD in predicting the occurrence of AF. Results: The levels of MnSOD were the highest in the paroxysmal AF group, followed by the persistent AF group, and the lowest in the controls. Meanwhile, the levels in the paroxysmal AF group were significantly higher than those in the controls [322.84 (165.46, 547.61) vs. 201.83 (129.53, 301.93), p = 0.002], but no significant difference was found between the paroxysmal AF group and persistent AF group, as well as the persistent AF group and the controls. Spearman correlation analysis indicated that there was a significantly negative correlation between MnSOD levels and LAD (r = −0.232, p = 0.008) and a positive correlation between MnSOD levels and RDW-CV (r = 0.214, p = 0.014) in the case group. Multivariate logistic regression analysis indicated that MnSOD levels [odds ratio (OR): 1.003, 95% confidence interval (CI): 1.001–1.005, p = 0.002] were an independent risk factor for paroxysmal AF, and the best cut-off value of MnSOD in predicting paroxysmal AF gained by ROC curve analysis was 311.49 ug/mL (sensitivity of 52.9%, specificity of 77.6%, AUC = 0.668). Conclusion: Oxidative stress underlies the pathogenesis of AF and may play a stronger role in paroxysmal AF than persistent AF. Our study showed an independent association between increased circulating plasma MnSOD levels and the occurrence of paroxysmal AF.

Association between red blood cell distribution width and non-valvular atrial fibrillation in hemodialysis patients: a single-center Chinese population study

Background Red blood cell distribution width (RDW) has emerged as a prognostic marker of atrial fibrillation (AF) in various clinical settings. However, the relationship by which RDW was linked to AF in hemodialysis (HD) patients was not clear. We sought to reveal the relationship between RDW and AF occurrence in HD patients. Methods We enrolled 170 consecutive maintenance HD patients, including 86 AF patients and 84 non-AF patients. All participants’ medical history and detailed clinical workup were recorded before the first dialysis session of the week. Electrocardiography, laboratory and transthoracic echocardiography examination indices were compared between the AF group and non-AF group. Multivariable logistic regression analysis was performed to identify the independent predictors of AF occurrence in HD patients. Results There were all paroxysmal AF patients in AF group. Compared to the non-AF group, patients with AF group had a significantly older age (61.0 ± 1.48 vs. 49.71 ± 1.79, p < 0.001), lower BMI (24.3 ± 4.11 vs. 25.8 ± 3.87, p < 0.05), higher RDW (15.10 ± 0.96 vs. 14.26 ± 0.82, p < 0.001) and larger LAD (39.87 ± 3.66 vs. 37.68 ± 5.08, p < 0.05). Multivariable logistic regression analyses demonstrated that values of age (OR: 1.030, 95%CI: 1.004-1.057, per one- year increase), BMI (OR: 0.863, 95%CI: 0.782–0.952, per 1 kg/m2 increase), RDW (OR: 2.917, 95%CI: 1.805–4.715, per 1% increase) and LAD (OR: 1.097, 95%CI: 1.004–1.199, per 1 mm increase) were independently associated with AF occurrence (p < 0.05, respectively). The best cutoff value of RDW to predict AF occurrence was 14.65% with a sensitivity of 68.6% and a specificity of 72.6%. Conclusions The increased RDW was significantly associated with the paroxysmal AF occurrence in HD patients.

Holter monitoring for assessment of possible paroxysmal atrial fibrillation as a cause in otherwise normal sinus rhythm patients with acute ischemic stroke: a hospital based study

Background: Stroke/ cerebrovascular accidents are common and among the major causes of mortality and morbidity. Thromboembolism are also among the causes of ischemic strokes. Diagnosis of atrial fibrillation makes the difference in the management of ischemic strokes for long term as anticoagulation are given in these cases for prevention of further embolic events.&#x0D; Methods: A prospective observational study was done from july 2019 to june 2021 for patients admitted for ischemic strokes who were otherwise found to have normal sinus rhythm. A 24 hour holter monitor was connected and analyzed for possible paroxysmal atrial fibrillation. Baseline investigations including trans-thoracic echocardiography was done. Data were analyzed and results were sought.&#x0D; Results: Out of 212 patients admitted for stroke, only 116 were eligible for the study. Male female ratio was 2:1. Ninety-four percent of patients had at least one or more risk factors: Smokers (74%) followed by Hypertensives (70%), Dyslipidemics (54%) and Diabetics (20%). Twenty-two percent of patients were found to have paroxysmal atrial fibrillation. There was no gender difference between the occurrences of paroxysmal atrial fibrillation. Among the risk factors, smoking and hypertension were significantly associated with the occurrence of paroxysmal atrial fibrillation (P: 0.001 and 0.002 respectively) while other risk factors like diabetes and dyslipidemia had no significant association. There was significant association of paroxysmal atrial fibrillation with mortality (P: 0.0013).&#x0D; Conclusion: Patients who are in otherwise normal sinus rhythm in electrocardiography with ischemic cerebrovascular accidents may have paroxysmal atrial fibrillation as cause of event. Smoking and hypertensive patients are significantly associated with occurrence of paroxysmal atrial fibrillation and stroke and these patients are more likely to die than the patients having normal heart rhythm. Management of these patients definitely defer in terms of possible use of anticoagulants.

On the reflexogenic and sensitizing role of cholecystitis in the pathogenesis of paroxysmal atrial fibrillation

Paroxysmal atrial fibrillation in the absence of mitral stenosis, myocarditis, cardiosclerosis and thyrotoxicosis is very rare. So, NM Davidovsky, BP Kushelevsky and others described the occurrence of paroxysmal atrial fibrillation after concussions in people with a healthy heart.

Reproducibility of Occurrence of Paroxysmal Atrial Fibrillation in Patients Who Had Acetylcholine Testing

Reproducibility of Occurrence of Paroxysmal Atrial Fibrillation in Patients Who Had Acetylcholine Testing

P wave dispersion over two decades after its discovery. What the cardiologist should know

For years, there has been an increase in cases of atrial fibrillation, reaching alarming levels. This is why intense work is done to find predictors of this arrhythmia. The electrocardiogram has shown to be useful for this purpose, and multiple indices derived from the P wave have been developed. Among the most notable is the P wave dispersion (PWD). It has been verified that PWD can predict the occurrence of paroxysmal atrial fibrillation in the absence of diseases as well as in the context of multiple cardiovascular pathologies or other systems. PWD is considered by most researchers to be the result of inhomogeneous conduction of the atrial electrical impulse, but a vector explanation may play a role in its genesis. The large body of evidence surrounding PWD supports its use in clinical practice.

P3748Reproducibility of magnetocardiographic imaging of atrial electrophysiology in patients with paroxysmal atrial fibrillation and healthy subjects

Abstract Since tangential currents are better detectable as magnetic than electric signals at the body surface, magnetocardiographic mapping (MCG) can be more sensitive than ECG to atrial electrophysiologic alteration, such as abnormal interatrial conduction and/or dispersion of atrial repolarization, as mechanisms underlying the occurrence of paroxysmal atrial fibrillation (PAF). We had previously reported that visual analysis of the magnetic field distribution (MFD) dynamics may evidence an inversion of atrial MFD early during the P-wave suggesting atrial repolarization overlapping depolarization along the descending limb of the P-wave (Guida et al 2018). Aim of this study was to systematically evaluate the reproducibility of such observation and to evaluate the reliability of non-invasive MCG imaging of atrial electrophysiology carried out in our unshielded hospital laboratory. Methods MCG was recorded, in sinus rhythm (SR), with an unshielded 36-channel SQUID-system providing about 30–40 fT/√Hz sensitivity in bandwidth DC-250Hz (sampling frequency 1kHz). MCG data of 40 patients with PAF (PAFp) and 40 age-matched healthy controls (HC), with at least two subsequent recordings to evaluate reproducibility and optimal S/N ratio, were retrospectively analyzed. The dynamics of atrial MFD was studied, at 1 ms time resolution, to identify the onset of atrial repolarization (AR), in respect of the P-wave and PR interval duration. To localize atrial sources, the inverse solution was calculated with the Effective Magnetic Dipole (EMD) model, also after subtraction of the atrial repolarization. MCG parameters of atrial electromagnetic vector (EMV) were also calculated. The reproducibility was evaluated with the intraclass correlation coefficient (ICC). Results High resolution analysis of atrial MFD dynamics confirmed that atrial repolarization field overlaps atrial depolarization during the last third of the P-wave in most investigated subjects. Thus, subtraction of average AR MFD is necessary to discover and image the left atrial depolarization pathway. The reproducibility of MCG estimate of atrial MFD and of EMV parameters was good (average ICC &gt;0.7). In PAFp, MCG evidenced abnormality of AR MFD consistent with dispersion of atrial repolarization (Figure 1), as previously reported with simultaneous MCG and MAP recordings (Fenici &amp; Brisinda, 2007); however, such evaluation is reliable only with optimal S/N ratio during the PR interval. Conclusions Unshielded MCG in SR is sensitive enough to non-invasively image atrial electrophysiology. Visual analysis of atrial MFD dynamics with high temporal resolution reproductively confirmed that AR MFD initiates early, within the descending limb of the P-wave, masking the deeper magnetic field generated by left atrial depolarization currents. MCG can image abnormality of AR MFD in PAFp, suggestive of dispersion of atrial action potential duration. Quantitative estimate of atrial EMV parameters differentiates PAFp from HC.

Влияние факторов риска развития и прогрессирования сердечно-сосудистых заболеваний на частоту пароксизмов фибрилляции предсердий у женщин трудоспособного возраста

Влияние факторов риска развития и прогрессирования сердечно-сосудистых заболеваний на частоту пароксизмов фибрилляции предсердий у женщин трудоспособного возраста

Can the development of atrial fibrillation in patients with ischemic heart failure with low ejection fraction be predicted?

OBJECTIVE:Our aim is to determine the triggering factors of paroxysmal atrial fibrillation (PAF) in ischemic heart failure (HF) patients with low ejection fraction (EF).METHODS:Sixty patients were included in this study. Echocardiography and 24-hours Holter monitoring were performed after measurement of serum NT-pro BNP concentration. The patients were classified into two groups concerning the occurrence of PAF on Holter recordings. Biochemical and echocardiographic parameters of patients with and without PAF were compared.RESULTS:PAF was detected in 28 (46%) patients. Patients with PAF demonstrated higher NT-pro BNP levels, mitral and aortic regurgitation velocities, E/A, E/E’, pulmonary capillary wedge pressure, pulmonary artery systolic pressure, left atrial volume and volume indices. NT-pro BNP was established as the predictor of PAF (OR=1.23, 95% CI: 1.08–1.42; p=0.001). ROC analysis showed an NT-pro BNP value of 2188 pg/mL as cut-off value with 68% sensitivity and 84% specificity [Area under the ROC curve (AUC)=0.826, CI 95%: 0.724–0.927; p<0.001].CONCLUSION:The triggering factors for AF are increased intracardiac pressures, left atrial dilatation and increased wall tension. As an indicator of increased wall tension, elevated levels of NT-pro BNP predict the development of PAF.

Occurrence of Paroxysmal Atrial Fibrillation at the Beginning of an Additional Resection during Neck Dissection

Occurrence of Paroxysmal Atrial Fibrillation at the Beginning of an Additional Resection during Neck Dissection

Double atrial potentials in left-sided accessory pathways are associated with paroxysmal atrial fibrillation.

Muscular connections between the coronary sinus (CS) and left atrium probably impact distribution of electrical activity. Double atrial potentials (DP) may be their presentation. The aim was to investigate the presence of DP in CS recordings during atrioventricular reentrant tachycardia (AVRT) and its contribution to the occurrence of paroxysmal atrial fibrillation (AF). A group of 247 patients with accessory pathways (AP) were screened for DP. The patients with DP during AVRT were compared to those without DP. DP during AVRT were found only among the left-sided AP (AP-L). Patients with AP-L were divided into Group 1 (n=17) with DP during AVRT and Group 2 (n=108) without DP. Patients in Group 1 had higher incidence of AF in history (47.1%vs. 23.1%; P=0.0376), AF induced during electrophysiological (EP) study (70.6%vs. 25%; P=0.0002). Group1 had higher heart rate (HR) during AVRT in the EP study (197.2 ± 27vs. 175.1 ± 26.3bpm; P=0.0019), but HR of clinical AVRT (208.5 ± 30.8vs. 191.6 ± 27.8bpm) was not significant different (P=ns). Additionally, electrical alternans of QRS amplitude during AVRT in the EP study was more frequent in Group1 (52.9vs. 20.4 %; P=0.0048). Patients with DP and AP-L were more prone to develop AF. The presence of DP was associated with faster AVRT rate. The direction of atrium depolarization during AVRT may be different in the presence of DP and probably plays a role in development of AF in this group of patients.

Simulated Obstructive Sleep Apnea Increases P-Wave Duration and P-Wave Dispersion.

BackgroundA high P-wave duration and dispersion (Pd) have been reported to be a prognostic factor for the occurrence of paroxysmal atrial fibrillation (PAF), a condition linked to obstructive sleep apnea (OSA). We tested the hypothesis of whether a short-term increase of P-wave duration and Pd can be induced by respiratory manoeuvres simulating OSA in healthy subjects and in patients with PAF.Methods12-lead-electrocardiography (ECG) was recorded continuously in 24 healthy subjects and 33 patients with PAF, while simulating obstructive apnea (Mueller manoeuvre, MM), obstructive hypopnea (inspiration through a threshold load, ITH), central apnea (AP), and during normal breathing (BL) in randomized order. The P-wave duration and Pd was calculated by using dedicated software for ECG-analysis.ResultsP-wave duration and Pd significantly increased during MM and ITH compared to BL in all subjects (+13.1ms and +13.8ms during MM; +11.7ms and +12.9ms during ITH; p<0.001 for all comparisons). In MM, the increase was larger in healthy subjects when compared to patients with PAF (p<0.05).ConclusionIntrathoracic pressure swings through simulated obstructive sleep apnea increase P-wave duration and Pd in healthy subjects and in patients with PAF. Our findings imply that intrathoracic pressure swings prolong the intra-atrial and inter-atrial conduction time and therefore may represent an independent trigger factor for the development for PAF.

Predicting Paroxysmal Atrial Fibrillation in Cerebrovascular Ischemia Using Tissue Doppler Imaging and Speckle Tracking Echocardiography

Often the underlying cause of cerebral ischemia (CI) cannot be found during a routine diagnostic investigation, but paroxysmal atrial fibrillation (PAF) could be the culprit. The objective of the study is to investigate whether advanced echocardiography improves the diagnostic approach for PAF in CI. The study included 286 CI patients with an echocardiogram in sinus rhythm. Patients were divided by PAF occurrence (PAF: n = 86, non-PAF: n = 200). PAF was defined as 1 or more reported episodes of atrial fibrillation. Echocardiograms consisted of conventional measures, tissue Doppler imaging (TDI), and speckle tracking. TDI was performed to acquire myocardial peak velocities during systole/ventricular contraction (global s'), early diastole/ventricular filling (global e'), and late diastole/atrial contraction (global a'). Speckle tracking was performed for myocardial strain analysis, thereby retrieving global longitudinal strain and global strain rate (s, e, a) values. Patients with PAF exhibited significantly impaired atrial contractile measures: global a' (-7.0 cm/second versus -5.7 cm/second, P < .001) and global strain rate a (.97 second(-1) versus .81 second(-1), P < .001). Both were univariable markers of PAF, and along with age remained the only independent significant determinants of PAF after multivariable logistic regression. Area under the curve (AUC) for age, global a', and global strain rate a significantly exceeded AUC for age alone (.79 versus .76, P = .032). Cutoff values with the highest sensitivity and specificity for these 3 parameters improved the diagnostic accuracy (sensitivity = 97%, specificity = 32%, negative predictive value = 95%, and positive predictive value = 38%). Atrial contractile measures by advanced echocardiography are significant determinants of PAF in CI. However, there is no discriminatory power to make them clinically useful at the current moment.

Beneficial effects of losartan for prevention of paroxysmal atrial fibrillation in patients with sick sinus syndrome: analysis with memory function of pacemaker.

Renin-angiotensin system (RAS) inhibitors may be useful in preventing the occurrence of paroxysmal atrial fibrillation (PAF). However, evaluation of such effect is difficult because many PAF episodes are asymptomatic and not all episodes are detected by intermittent electrocardiographic monitoring. A pacemaker has been developed with dedicated functions for AF detection and electrocardiogram storage. Accordingly, we examined the effect of losartan, an angiotensin receptor blocker on PAF occurrence using this new modality. We enrolled 70 consecutive patients who had undergone dual-chamber pacemaker implantation for sick sinus syndrome. Finally, 62 patients participated in the study. Thirty patients were randomized to the losartan group (mean 43 ± 12 mg/day) and 32 patients to the control group. They were followed up for 3 months. The frequency, the maximum duration and the total duration of PAF recorded by the stored electrocardiograms for the last 1 month during the observation period and study period were compared between the two groups. The change in the frequency of PAF from the observation period in the losartan and control groups was similar (-35 ± 25 vs. -67 ± 62 times; NS). However, the change in the maximum duration and the total duration of PAF was significantly shorter in the losartan group than in the control group (-493 ± 158 vs. -10 ± 69 min; p < 0.05, and -4007 ± 2334 vs. 1119 ± 714 min; p < 0.05, respectively). Losartan suppressed the maximum duration and the total duration of PAF in patients with sick sinus syndrome without hemodynamic changes. This is the first study to show the effect of a renin-angiotensin system inhibitor on the secondary prevention of PAF using the dedicated functions of a pacemaker for PAF detection and electrocardiogram storage.

Atrial fibrillation following low voltage electrical injury

This is a case report of occurrence of paroxysmal atrial fibrillation (AF) in a previously healthy 50-year-old man after suffering from a nonfatal electrical injury. The patient developed palpitation and sustained nonfatal electrical burn in his right hand after coming in contact with 440 voltage alternating current. His electrocardiogram done at the emergency revealed AF. However he was hemodynamically stable and hence put under conservative therapy. He reverted back to sinus rhythm within 24 h of admission and continued to remain so. Although ventricular arrhythmia is common after electrical injury, AF has been rarely reported in literature.