Impact of electrical cardioversion for atrial fibrillation on left atrial appendage function and spontaneous echo contrast: characterization by simultaneous transesophageal echocardiography

In Situ Transesophageal Echocardiography During Electrical Cardioversion in Patients With Atrial Fibrillation-Safety and Echocardiographic Findings

BACKGROUND

Transesophageal echocardiography (TEE) can reliably detect left atrial (LA) and LA appendage (LAA) thrombus in patients with atrial fibrillation (AF) before electrical cardioversion (ECV). However, evaluating cardiac and valve function pre-ECV can be challenging due to the increased and irregular heart rate. Additionally, post-ECV atrial stunning increases the risk of LAA thrombosis. Therefore, post-ECV TEE may allow for useful appendage, ventricular, and valve function assessment. However, the safety and usefulness of leaving the TEE probe in situ during ECV for post-ECV cardiac evaluation in clinical practice have not been previously evaluated.

METHODS

We analyzed 37 out of 86 consecutive patients who had the TEE probe left in situ, for clinical reasons, during ECV by a single operator between February 20, 2019, and January 3, 2023. We examined changes in left ventricular (LV) function, dynamic changes in valvular regurgitation, electromechanical coupling of the left atrium, and qualitative spontaneous echo contrast. We also assessed the presence of any complications related to the periprocedural TEE exam.

RESULTS

The mean age of the patients was 74 ± 9.65 years, and 29 (78%) were male. The periprocedural TEE time ranged from 7 to 55 minutes, with an average of 20.78 minutes. Immediately after ECV and restoration of normal sinus rhythm, there was an improvement in LV ejection fraction (47% ± 11.9% vs 40% ± 15.8%; P = .035). There was also a reduction in baseline mitral regurgitation of greater than moderate degree. However, spontaneous echo contrast worsened in the LAA in 11 (31.4%) patients. Additionally, 1 patient developed a new LAA thrombus, and 24 patients (72%) had evidence of electromechanical coupling with Doppler evidence of LA contraction. Clinically significant degenerative aortic and mitral stenosis were identified in 8% and mild or greater aortic regurgitation in 8% of patients post-ECV. No procedural complications were observed.

CONCLUSIONS

In situ TEE before, during, and after ECV is safe and provides useful clinical information regarding immediate cardiac changes after ECV, with diagnostic and therapeutic implications.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Transesophageal Echocardiogram Before Cardioversion in Atrial Fibrillation Patients

Transesophageal echocardiography (TEE) offers an invaluable, non-invasive avenue for diagnosing and managing various cardiac conditions, including atrial fibrillation (AF). As the most common cardiac arrhythmia, AF affects millions and can lead to severe complications. Cardioversion, a procedure to restore the heart's normal rhythm, is frequently conducted on AF patients resistant to medication. Due to inconclusive data, TEE's utility prior to cardioversion in AF patients remains ambiguous. Understanding TEE's potential benefits and limitations in this population could significantly influence clinical practice. This review aims to scrutinize the current literature on the use of TEE before cardioversion in AF patients. The principal objective is to understand TEE's potential benefits and limitations comprehensively. The study seeks to offer a clear understanding and practical recommendations for clinical practice, thereby improving the management of AF patients before cardioversion using TEE. A literature search of databases was conducted using the keywords "Atrial Fibrillation," "Cardioversion" and "Transesophageal echocardiography," resulting in 640 articles. These were narrowed to 103 following title and abstract reviews. After applying exclusion and inclusion criteria with a quality assessment, 20 papers were included: seven retrospective studies, 12 prospective observational studies, and one randomized controlled trial (RCT). Stroke risk associated with direct-current cardioversion (DCC) potentially results from post-cardioversion atrial stunning. Thromboembolic events occur post cardioversion, with or without prior atrial thrombus or cardioversion complications. Generally, cardiac thrombus localizes in the left atrial appendage (LAA), a clear contraindication to cardioversion. Atrial sludge without LAA thrombus in TEE is a relative contraindication. TEE before electrical cardioversion (ECV) in anticoagulated AF individuals is uncommon. In AF patients planned for cardioversion, contrast enhancement facilitates thrombus exclusion in TEE images, reducing embolic events. Left atrial thrombus (LAT) frequently occurs in AF patients, necessitating TEE examination. Despite the increased use of pre-cardioversion TEE, thromboembolic events persist. Notably, patients with post-DCC thromboembolic events had no LA thrombus or LAA sludge. The use of TEE-guided DCC has grown due to its ability to detect atrial thrombi pre-cardioversion, aiding risk stratification. Thrombus in the left atrium also signals an elevated risk of future thromboembolic events in AF patients. While atrial stunning post cardioversion detected by TEE is a significant risk factor for future thromboembolic events, further evidence is required. Therapeutic anticoagulation is essential during and post cardioversion, even if no atrial thrombus is detected. Current data recommends cardioversion guided by TEE, particularly in outpatient settings.

Left atrial reservoir and pump function after catheter ablation with persistent atrial fibrillation: a two-dimensional speckle tracking imaging study

OBJECTIVE

By using ultrasound strain rate (SR) imaging to evaluate the left atrial (LA) reservoir and pump function after catheter ablation (CA) with persistent atrial fibrillation (PAF).

METHODS

A total of 45 patients with PAF underwent echocardiography examination before and after ablation as well as during 6 months of follow-up. Peak SR was measured at each LA segment (septal, lateral, anterior, inferior and posterior) during systole (LAs) and late diastole (LAa).

RESULTS

During 6 months after CA, 30 patients were free of atrial fibrillation recurrence (AFR). left atrial area index (LAAI), left atrial maximum volume index (LAVImax), and E/Ea were obviously higher in patients with before CA, left atrial ejection fraction (LAEF), SR-LAs were lower than in normal cases, the SR-LAa was disappeared. Shortly after ablation, SR-LAa was recovered, and SR-LAs was reduced compared to those at baseline. At midterm follow-up, LAEF and SR-LAs were still lower than the control group, and LAAI and LAVImax were higher. SR-LAa was recovered slowly over time, but still lower.

CONCLUSION

LA reservoir function was seriously damaged and LA pump function disappeared in patients with PAF. LA reservoir function impairment appeared shortly after ablation, it showed improvement at midterm follow-up, but some degree of damage to the LA reservoir and pump function was still present. Speckle tracking imaging is a feasible technique for the assessment of LA function in patients with PAF, which is a potentially valuable clinical tool to assist in the early detection of atrial remodelling and reverse remodelling.

The risk and timing of acute ischemic stroke after electrical cardioversion for atrial fibrillation in Taiwan: A nationwide population-based cohort study

BACKGROUND

There is a positive association between electrical cardioversion (ECV) and acute ischemic stroke (AIS). Although 4 weeks of anticoagulation therapy after ECV in atrial fibrillation (AF) patients is generally suggested by current guidelines to reduce the risk of AIS, limited studies have been conducted in Asian populations to determine the risk and timing of AIS after ECV for AF in recent years. Therefore, we aim to use the National Health Insurance Research Database (NHIRD) in Taiwan to determine the risk and timing of AIS after ECV for AF.

METHODS

The data analyzed in this nationwide population-based retrospective cohort study were obtained from the NHIRD in Taiwan. The outcome in this study was the cumulative incidence of AIS in patients with AF during 7-day and 30-day follow-up periods after the patients underwent ECV.

RESULTS

Our analysis included 39,697 patients with AF, of whom 5723 received ECV and 5723 were propensity score-matched controls. Compared to the controls, patients who received ECV exhibited a significantly increased incidence of 7-day AIS development (adjusted hazard ratio [HR] = 1.524, p = 0.003). In contrast, the incidence of 30-day AIS development showed no significant increase (adjusted HR = 1.301, p = 0.426).

CONCLUSIONS

AF patients who underwent ECV had a higher incidence of 7-day AIS development but not 30-day AIS development. Considering the timing of AIS development after ECV in AF patients, the optimal duration of antithrombotic therapy after ECV deserves further investigation.

Cardioversion of Atrial Fibrillation with Acupuncture

Background: Atrial fibrillation, the most commonly treated arrhythmia, results in significant symptom burden, increased stroke risk, and costs 26 billion dollars annually in the United States alone. Maintaining sinus rhythm is often preferred, but current interventions have limitations and are associated with adverse effects. There are data suggesting that acupuncture can have a beneficial effect on maintaining sinus rhythm as well as limited data suggesting it can help convert atrial fibrillation to sinus rhythm in the acute setting. Case: An 82-year-old woman with history of heart failure with preserved ejection fraction as well as paroxysmal atrial fibrillation developed atrial fibrillation with rapid ventricular response during a hospitalization for acute exacerbation of heart failure and gastrointestinal bleeding. Given success in converting supraventricular tachycardia using ear Shen Men in a prior case as well as limited data suggesting a benefit of acupuncture in acute atrial fibrillation, acupuncture was utilized in the management of the acute atrial fibrillation. Acupuncture was initiated 4 hours after the arrhythmia began and a total of 8 ear points (4 each side) as well as bilateral pericardium 6 points were utilized. Results: Atrial fibrillation converted to sinus rhythm before the last needle was placed and the patient had no recurrence of atrial fibrillation throughout the remainder of her stay. Conclusions: Acupuncture appears to be solely responsible for the conversion of atrial fibrillation to sinus rhythm in this case, as no β-blockers, calcium channel blockers, or antiarrhythmic medicines were administered before the return to sinus rhythm. The antiarrhythmic effect noted may be from centrally mediated autonomic effects or additional mechanisms. Further study will help to define the role of acupuncture in the management of acute arrhythmias.

The impact of basic atrial rhythm during catheter ablation of atrial fibrillation on clinical outcomes: Lessons from the German Ablation Registry

BACKGROUND

The impact of basic atrial rhythm (sinus rhythm [SR] vs. atrial fibrillation [AF]) during AF ablation on efficacy and safety is unknown.

METHODS

About 3375 patients from the German Ablation Registry undergoing first-time AF ablation were divided according to the type of AF and the basic atrial rhythm during the ablation procedure: paroxysmal AF (PAF) and SR [group Ia], PAF and AF [group Ib]), persistent AF and SR (IIa), and persistent AF and AF (IIb).

RESULTS

Patients in SR (n = 2312 [67%]) underwent cryoballoon ablation more often (Ia vs. Ib p = .002 and IIa vs. IIb p = .010, whereas in patients in AF (n = 1063 [33%]) radiofrequency (RF)-based ablation (Ia vs. Ib p = .006 and IIa vs. IIb p = .014) including left and/or right atrial substrate modification was more frequently performed. Depending on the basic rhythm there was no difference regarding arrhythmia recurrence during long-term follow-up. For patients suffering from persistent AF acute procedure-related complications were more often documented when ablated in AF (9.1% vs. 4.6%, p = .012). which was mainly driven by the higher occurrence of pericardial effusion/tamponade. For patients suffering from persistent AF, favorable results were found regarding 366-day Kaplan-Meier estimates of the incidence of MACCE (death, myocardial infarction, and stroke; p = .011) and the composite endpoint of death, myocardial infarction, stroke, and major bleeding (p = .006), when ablated in SR.

CONCLUSION

Basic atrial rhythm at the time of AF ablation did not affect long-term rhythm outcome. For patients suffering from persistent AF a more favorable acute and long-term safety profile was observed when ablated in SR.

Renal Dysfunction following Direct Current Cardioversion of Atrial Fibrillation: Incidence and Risk Factors

INTRODUCTION

Emerging data suggest that cardioversion for atrial fibrillation (AF) may be associated with acute kidney injury (AKI). However, limited data are available regarding the incidence and risk factors for AKI after direct current cardioversion (DCCV) of AF.

METHODS

All patients undergoing DCCV at Mayo Clinic between 2001 and 2012 for AF were prospectively enrolled in a database. All patients with serum creatinine (SCR) values pre- and post-cardioversion were reviewed for AKI, defined as a ≥25% decline in eGFR (estimated glomerular filtration rate) from baseline value within 7 days of the DCCV.

RESULTS

Of the 6,427 eligible patients, 1,256 (19.5%) patients had pre- and post-DCCV SCR available and formed the cohort under study. The mean age was 70.4 (SD 11.7) years, and 67.3% were male. During the study period, 131 (10.4%) patients suffered from AKI following DCCV. AKI was independently associated with inpatient status (OR 26.79; 95% CI 3.69-194.52), CHA2DS2-VASc score (OR 1.25; 95% CI 1.11-1.41), prior use of diuretics (OR 1.59; 95% CI 1.03-2.46), and absence of CKD (OR 1.61; 95% CI 1.04-2.49), and was independent of the success of the DCCV. None of the patients required acute dialysis during the study outcome period.

CONCLUSION

AKI following DCCV of AF is common, self-limited, and without the need for replacement therapies.

Left Atrial Mechanics Assessed Early during Hospitalization for Cryptogenic Stroke Are Associated with Occult Atrial Fibrillation: A Speckle-Tracking Strain Echocardiography Study

BACKGROUND

Occult atrial fibrillation (AF) is an important contributor to cryptogenic stroke, yet remains difficult to unmask at presentation. This study investigated the predictive value of left atrial (LA) mechanics by strain echocardiography during stroke hospitalization for the presence of AF as detected on early 30-day monitoring and routine clinical follow-up.

METHODS

Left atrial mechanics were studied by strain echocardiography in a retrospective cohort of 191 patients with cryptogenic stroke and 30-day mobile cardiac outpatient telemetry poststroke to diagnose AF. After this, AF was diagnosed via routine clinical follow-up. The independent and incremental value of measures of LA size and mechanics (i.e., strain and strain rate in the reservoir, conduit, and booster pump phase) to predict AF on top of clinical characteristics was assessed.

RESULTS

Of 191 patients, 15% (n = 28) developed AF, of which 10 were observed during 30-day mobile cardiac outpatient telemetry and 18 were observed at a median follow-up of 25 (interquartile range, 10-43) months. Median time from embolic stroke to strain echocardiography was 1 day (interquartile range, 1-2 days). Left atrial mechanics were significantly worse in AF (P < .05 for all), despite largely similar baseline cardiovascular risk profile. Booster pump strain rate was the strongest predictor for AF, independent of age, LA volume index, E/e', and reservoir strain (odds ratio = 2.88 per SD increase; 95% confidence interval, 1.29-6.41; P = .010). Adding LA strain reservoir strain and booster pump function significantly enhanced a multivariate model to predict AF. Freedom from AF was significantly lower in subjects with a booster pump strain rate (at stroke presentation) worse than -0.67 sec^-1, as derived from receiver operator curve analysis (P < .001).

CONCLUSIONS

Left atrial mechanics and particularly the LA booster pump function assessed early during hospitalization for cryptogenic stroke can identify patients at greater likelihood of future diagnosis of AF. These findings could in part relate to LA mechanical stunning after spontaneous cardioversion, which-when identified by early strain echocardiography-can inform further risk stratification and decision-making.

The 2020 Canadian Cardiovascular Society/Canadian Heart Rhythm Society Comprehensive Guidelines for the Management of Atrial Fibrillation

The Canadian Cardiovascular Society (CCS) atrial fibrillation (AF) guidelines program was developed to aid clinicians in the management of these complex patients, as well as to provide direction to policy makers and health care systems regarding related issues. The most recent comprehensive CCS AF guidelines update was published in 2010. Since then, periodic updates were published dealing with rapidly changing areas. However, since 2010 a large number of developments had accumulated in a wide range of areas, motivating the committee to complete a thorough guideline review. The 2020 iteration of the CCS AF guidelines represents a comprehensive renewal that integrates, updates, and replaces the past decade of guidelines, recommendations, and practical tips. It is intended to be used by practicing clinicians across all disciplines who care for patients with AF. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) system was used to evaluate recommendation strength and the quality of evidence. Areas of focus include: AF classification and definitions, epidemiology, pathophysiology, clinical evaluation, screening and opportunistic AF detection, detection and management of modifiable risk factors, integrated approach to AF management, stroke prevention, arrhythmia management, sex differences, and AF in special populations. Extensive use is made of tables and figures to synthesize important material and present key concepts. This document should be an important aid for knowledge translation and a tool to help improve clinical management of this important and challenging arrhythmia.

Transient atrial mechanical dysfunction assessed in acute phase of embolic stroke of undetermined source

BACKGROUND AND PURPOSE

Paroxysmal atrial fibrillation (PAF) has been suggested as a major cause of embolic stroke of undetermined source (ESUS). Transient atrial mechanical dysfunction (stunning) frequently occurs after conversion of atrial fibrillation to sinus rhythm. The study aim was to determine if reversible atrial mechanical dysfunction in ESUS could help elucidate the mechanism of stroke.

METHODS

Eighty-five consecutive patients with acute ischemic stroke were enrolled according to the following inclusion criteria: [1] ≥55 years old; [2] normal sinus rhythm upon admission; [3] no apparent embolic source; and [4] transthoracic echocardiographic evaluation had been performed in both the early phase (<72 h) and late phase (>7 days) after stroke onset. There were 27 patients in the lacunar or atherothrombotic infarction group (controls), 22 in the PAF group, and 36 in the ESUS group. To determine atrial stunning, transmitral flow velocity profiles (Doppler peak E- [early diastolic] and A- [atrial systolic] waves) were obtained.

RESULTS

In the early phase, an E/A velocity ratio ≥ 1.0 was less common in the control group (1 patient, 3.7%) than in the PAF group (19 patients, 86.4%; p < 0.001) and ESUS group (10 patients, 27.8%; p < 0.05). In the late phase, the E/A ratio decreased to less than 1.0 in six patients (31.6%) who had PAF and in eight patients (80.0%) who had ESUS.

CONCLUSION

Transient atrial mechanical dysfunction could be a helpful finding for elucidating the stroke mechanism in patients with ESUS, and early echocardiographic assessment could improve its detection.

Opposite effect of ablation on early/late-phase thromboembolic incidence in patients with atrial fibrillation: A meta-analysis on more than 100 000 individuals

Background

Atrial fibrillation (AF) is an important risk factor for thromboembolic events, for which catheter ablation represents an effective therapy for rhythm control. Intuitively, ablation may reduce the incidence of thromboembolism, but data is quite limited.

Hypothesis

Catheter ablation was associated with the fewer risk of thromboembolism compared with nonablation in patients with AF.

Methods

A systematic search was performed in PubMed, EMBASE, the Web of Science, and the Cochrane Library from inception to September 2019. Random‐effects model was used to estimate the risk ratios (RR) for the thromboembolic events between the ablation and nonablation groups.

Results

Twenty‐five studies (12 randomized controlled trials and 13 observational studies) with 104 687 participants were included. Pooled analysis suggested that ablation was associated with a 35% lower risk of total thromboembolic events compared to nonablation group (RR = 0.65; 95% CI, 0.51‐0.82; P = .0003). When separated into early‐phase (<30 days) and late‐phase (>30 days) events, ablation was associated with an increased early‐phase thromboembolism (RR = 1.96; 95% CI, 1.35‐2.83; P = .0004) but a decreased late‐phase thromboembolism (RR = 0.75; 95% CI, 0.63‐0.90; P = .002). Subgroup analysis according to different study types found similar results were found in observation studies, but not in RCT studies because the sample size was too small to be conclusive.

Conclusions

In patients with AF, catheter ablation was associated with a fewer risk of overall and late‐phase thromboembolism in comparison with nonablation. However, over the early postoperative period, catheter ablation was associated with the double higher risk of thromboembolic events.

2018 Focused Update of the Canadian Cardiovascular Society Guidelines for the Management of Atrial Fibrillation

The Canadian Cardiovascular Society (CCS) Atrial Fibrillation Guidelines Committee provides periodic reviews of new data to produce focused updates that address clinically important advances in atrial fibrillation (AF) management. This 2018 Focused Update addresses: (1) anticoagulation in the context of cardioversion of AF; (2) the management of antithrombotic therapy for patients with AF in the context of coronary artery disease; (3) investigation and management of subclinical AF; (4) the use of antidotes for the reversal of non-vitamin K antagonist oral anticoagulants; (5) acute pharmacological cardioversion of AF; (6) catheter ablation for AF, including patients with concomitant AF and heart failure; and (7) an integrated approach to the patient with AF and modifiable cardiovascular risk factors. The recommendations were developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) standards. Individual studies and literature were reviewed for quality and bias; the literature review process and evidence tables are included as Supplementary Material and are available on the CCS Web site. Details of the updated recommendations are presented, along with their background and rationale. This document is linked to an updated summary of all CCS AF guidelines recommendations, from 2010 to the present 2018 Focused Update, which is provided in the Supplementary Material.

Clinical outcomes after AF cardioversion in patients presenting left atrial sludge in trans-esophageal echocardiography

BACKGROUND

Direct-current cardioversion (DCC) for atrial fibrillation carries a risk of stroke, probably associated with the temporary atrial stunning following cardioversion. The presence of a cardiac thrombus, usually localized in the left atrial appendage (LAA), is recognized as a clear contra-indication to the cardioversion. However, the presence of atrial sludge without LAA thrombus in trans-esophageal echocardiography (TEE) remains, for many cardiologists, a relative contra-indication to the cardioversion. The aim of this study was to evaluate the safety of DCC in patients presenting atrial sludge without LAA thrombus.

METHODS

We prospectively included all consecutive patients demonstrating atrial sludge without LAA thrombus in TEE and undergoing DCC for persistent atrial fibrillation (AF). Safety of DCC was evaluated by the occurrence of clinical events at 1 month following cardioversion, i.e., up to the end of the atrial stunning period, as assessed by clinical examination and the standardized and validated Questionnaire for Verifying Stroke-Free Status (QVSFS).

RESULTS

Over a period of 2 years, 21 patients presenting atrial sludge without LAA thrombus underwent DCC for AF. During the follow-up period of 1 month after DCC, no clinical embolic event, cardiac event, or unscheduled consultations/hospitalizations occurred. At 1 month, 67% of the patients remained in sinus rhythm.

CONCLUSION

No clinical event occurred in patients demonstrating atrial sludge without thrombus and undergoing DCC for AF. These findings support current guidelines that only keep atrial thrombus as a contraindication to cardioversion, but warrant further investigation in large studies.

Atrial electromechanical delay assessment in early phase after catheter ablation for patients with atrial fibrillation

BACKGROUND

Variation of atrial electromechanical delay (AED) in early phase after catheter ablation in patients with atrial fibrillation (AF) is lacking.

METHODS

Fifty-five consecutive patients restored sinus rhythm after ablation was included. Echocardiography was performed at 4 h, 1 day, and 3 days after radiofrequency catheter ablation, and AED was measured simultaneously by echocardiography with pulse Doppler imaging and pulse wave tissue Doppler imaging.

RESULTS

AED parameters were significantly longer in the nonparoxysmal atrial fibrillation (NPAF) group than in the paroxysmal atrial fibrillation (PAF) group at each checking point after ablation (P < 0.05). Compared with other checking points, AED parameters were significantly longer 4 h postablation in the NPAF group, while no significant difference was found between different checking points in the PAF group. AED-leap, representing the variation of AED in NPAF patients, was significantly positively correlated with the duration of NPAF (r = 0.5291, P = 0.0113).

CONCLUSIONS

Compared with PAF, NPAF patients have a longer AED postablation, and an abrupt decrease in the initial-h postablation. Such phenomenon gives rise to the different clinical features of PAF and NPAF, and could guide different assessment and treatment strategies for different types of AF.

Cardioversion for atrial fibrillation - how to prevent thromboembolic complications?

Cardioversion is an essential component of rhythm control strategy for atrial fibrillation. The thromboembolic risk of cardioversion is well established and the mechanisms behind the phenomenon have been comprehensively described. There are several clinical aspects that are important to take into consideration when assessing the safety of cardioversion. Before proceeding to cardioversion, the probability of early treatment failure and antiarrhythmic treatment options to prevent recurrences should be carefully evaluated to avoid the risks of repeated futile cardioversions. Effective periprocedural anticoagulation is the mainstay in thromboembolic complication prevention and the first week after rhythm conversion is the most vulnerable period in this respect. Early timing of cardioversion appears to be another important measure to decrease the risk of thromboembolic complications. Transoesophageal echocardiography is useful in clinical scenarios where early cardioversion is desirable due to debilitating clinical symptoms and a short duration of arrhythmia or the adequacy of preceding anticoagulation is uncertain. However, it does not lessen the need for effective anticoagulation after cardioversion. This review summarizes the recent scientific discoveries to improve the safety of cardioversion for atrial fibrillation. Key messages Cardioversion for atrial fibrillation entails a significant risk of thromboembolic complications, especially during the first week after the procedure. The intensity of periprocedural anticoagulation and the timing of cardioversion appear to be significant determinants of the risk of thromboembolism. Awareness of the clinical aspects influencing cardioversion safety should be raised.

Can catheter ablation reduce the incidence of thromboembolic events in patients with atrial fibrillation?: Protocol for a systematic review and meta-analysis

Atrial fibrillation (AF), the most common cardiac arrhythmia, is a major risk factor for thromboembolic events, especially ischemic stroke. Catheter ablation is an effective method to maintain sinus rhythm in patients with AF. Although some observational studies have shown a relatively lower stroke rate after catheter ablation, whether catheter ablation can reduce the thromboembolic risk in patients with AF remains unclear. We aim to perform a systematic review to determine whether catheter ablation can prevent thromboembolism in patients with AF.PubMed, Embase, the Web of Science, and the Cochrane Library will be searched from January 2000 to the present for randomized controlled trials (RCTs) and non-randomized studies on catheter ablation in patients with AF. Other relevant sources, such as the references and conference proceedings, will also be manually retrieved. All studies will be limited to publication in English. The primary outcome will be thromboembolic events, including stroke, transient ischemic attack, and systemic embolic events. Study screening, data collection, and study quality assessment will be independently performed by 2 researchers. Disagreements will be resolved through team discussion or consultation with a third arbitrator. The risk of bias will be appraised using the Cochrane Collaboration tool and the Newcastle-Ottawa scale according to the different study designs, and a meta-analysis will be performed using RevMan V.5.3 software. The results will be presented as risk ratios and 95% confidence intervals for dichotomous data and continuous outcomes.Catheter ablation is an effective method to cure atrial fibrillation and maintain sinus rhythm. Although it is intuitive that if AF is eliminated, the thromboembolism in the heart would be abolished, and sequently the incidence of thromboembolic events would be decreased, this in fact has not yet been clarified. This systematic review and meta-analysis will be performed with the aim of comprehensively identifying studies that have reported the impact of AF ablation on thromboembolic events in patients with non-valvular AF by comparing an ablation group and non-ablation group. These outcomes will not only produce useful evidence-based data regarding the influence of catheter ablation on thromboembolic events in patients with AF but will also provide some guidance regarding anticoagulation regimens in patients who have undergone catheter ablation.

Cardioverting acute atrial fibrillation and the risk of thromboembolism: not all patients are created equal

Current guidelines support the well-established clinical practice that patients who present with atrial fibrillation (AF) of less than 48 hours duration should be considered for cardioversion, even in the absence of pre-existing anticoagulation. However, with increasing evidence that short runs of AF confer significant risk of stroke, on what evidence is this 48-hour rule based and is it time to adopt a new approach? We review existing evidence and suggest a novel approach to risk stratification in this setting. Overall, the risk of thromboembolism associated with acute cardioversion of patients with AF that is estimated to be of <48 hours duration is low. However, this risk varies widely depending on patient characteristics. From existing evidence, we show that using the CHA2DS2-VASc score may allow better selection of appropriate patients in order to prevent exposing specific patient groups to an unacceptably high risk of a potentially devastating complication.

Atorvastatin can ameliorate left atrial stunning induced by radiofrequency ablation for atrial fibrillation

The objective of this study was to study the functional changes of the left atrium after radiofrequency ablation treatment for atrial fibrillation and the therapeutic effect of atorvastatin. Fifty-eight patients undergoing radiofrequency ablation for atrial fibrillation were randomly divided into non-atorvastatin group and atorvastatin group. Patients in the atorvastatin group were treated with atorvastatin 20 mg p.o. per night in addition to the conventional treatment of atrial fibrillation; patients in the non-atorvastatin group received conventional treatment of atrial fibrillation only. Echocardiography was performed before radiofrequency ablation operation and 1 week, 2 weeks, 3 weeks, and 4 weeks after operation. Two-dimensional ultrasound speckle tracking imaging system was used to measure the structural indexes of the left atrium. Results indicated that there was no significant change for indexes representing the structural status of the left atrium within a month after radiofrequency ablation (P > 0.05); however, there were significant changes for indexes representing the functional status of the left atrium. There were also significant changes in indexes reflecting left atrial strain status: the S and SRs of atorvastatin group were higher than those of non-atorvastatin group (P < 0.05). In summary, atorvastatin could improve left atrial function and shorten the duration of atrial stunning after radiofrequency ablation of atrial fibrillation.

Predicting Unsuccessful Electrical Cardioversion for Acute Atrial Fibrillation (from the AF-CVS Score)

Electrical cardioversion (ECV) is the standard treatment for acute atrial fibrillation (AF), but identification of patients with increased risk of ECV failure or early AF recurrence is of importance for rational clinical decision-making. The objective of this study was to derive and validate a clinical risk stratification tool for identifying patients at high risk for unsuccessful outcome after ECV for acute AF. Data on 2,868 patients undergoing 5,713 ECVs of acute AF in 3 Finnish hospitals from 2003 through 2010 (the FinCV study data) were included in the analysis. Patients from western (n = 3,716 cardioversions) and eastern (n = 1,997 cardioversions) hospital regions were used as derivation and validation datasets. The composite of cardioversion failure and recurrence of AF within 30 days after ECV was recorded. A clinical scoring system was created using logistic regression analyses with a repeated-measures model in the derivation data set. A multivariate analysis for prediction of the composite end point resulted in identification of 5 clinical variables for increased risk: Age (odds ratio [OR] 1.31, confidence interval [CI] 1.13 to 1.52), not the First AF (OR 1.55, CI 1.19 to 2.02), Cardiac failure (OR 1.52, CI 1.08 to 2.13), Vascular disease (OR 1.38, CI 1.11 to 1.71), and Short interval from previous AF episode (within 1 month before ECV, OR 2.31, CI 1.83 to 2.91) [hence, the acronym, AF-CVS]. The c-index for the AF-CVS score was 0.67 (95% CI 0.65 to 0.69) with Hosmer-Lemeshow p value 0.84. With high (>5) scores (i.e., 12% to 16% of the patients), the rate of composite end point was ∼40% in both cohorts, and among low-risk patients (score <3), the composite end point rate was ∼10%. In conclusion, the risk of ECV failure and early recurrence of AF can be predicted with simple patient and disease characteristics.

Advances in anticoagulation management of patients undergoing cardioversion of nonvalvular atrial fibrillation

Atrial fibrillation (AF) is a major cause of stroke. The restoration of sinus rhythm through cardioversion, either chemical or electrical is a common practice. Interestingly, there is an incremental increase from the baseline risk for embolisation in the immediate post-cardioversion period, with most events occurring within 10 days from cardioversion. Especially patients with recent onset AF show the lowest rates of antithrombotic therapy, while having a high stroke risk. Despite the increased risk for embolisation, anticoagulation in patients undergoing cardioversion of atrial fibrillation is often inadequate. Moreover, since the implementation of non-vitamin K antagonists oral anticoagulants (DOACs) there are several therapeutic approaches for pericardioversion anticoagulant therapy and not all suits to all patients. In addition, the extensive use of transesophageal echocardiography provides an alternative strategy, especially useful for patients of high haemorrhagic risk. In this review article, we aim to provide an update on the anticoagulation strategies for patients undergoing cardioversion of non-valvular atrial fibrillation in the advent of the use of DOACs.

Guidelines for the Use of Echocardiography in the Evaluation of a Cardiac Source of Embolism

Embolism from the heart or the thoracic aorta often leads to clinically significant morbidity and mortality due to transient ischemic attack, stroke or occlusion of peripheral arteries. Transthoracic and transesophageal echocardiography are the key diagnostic modalities for evaluation, diagnosis, and management of stroke, systemic and pulmonary embolism. This document provides comprehensive American Society of Echocardiography guidelines on the use of echocardiography for evaluation of cardiac sources of embolism. It describes general mechanisms of stroke and systemic embolism; the specific role of cardiac and aortic sources in stroke, and systemic and pulmonary embolism; the role of echocardiography in evaluation, diagnosis, and management of cardiac and aortic sources of emboli including the incremental value of contrast and 3D echocardiography; and a brief description of alternative imaging techniques and their role in the evaluation of cardiac sources of emboli. Specific guidelines are provided for each category of embolic sources including the left atrium and left atrial appendage, left ventricle, heart valves, cardiac tumors, and thoracic aorta. In addition, there are recommendation regarding pulmonary embolism, and embolism related to cardiovascular surgery and percutaneous procedures. The guidelines also include a dedicated section on cardiac sources of embolism in pediatric populations.

Quantitative analysis of the right auricle with 256-slice computed tomography

PURPOSE

To quantitatively measure the morphology parameters of the right auricle with 256-slice multidetector computed tomography angiography (MDCTA) in healthy people.

MATERIALS AND METHODS

A retrospective analysis of 200 patients who had undergone coronary MDCTA with negative findings was performed. The raw imaging data were reconstructed and the right auricular volume, right atrial volume, right auricle height, base long and short axes, base perimeter and area, normal angle, and distance were quantitatively measured.

RESULTS

Men had significantly (P < 0.05) greater values than women in the right auricular volume (13.3 ± 4.0 vs. 11.7 ± 3.7 mL) and height (33.0 ± 5.0 vs. 30.5 ± 5.2 mm), the base long axis (34.4 ± 4.1 vs. 33.2 ± 3.9 mm), area (787.6 ± 177.6 vs. 771.0 ± 143.2 mm²) and perimeter (119.2 ± 17.5 vs. 115.0 ± 13.0), and the normal distance (22.4 ± 6.6 vs. 20.2 ± 6.7 mm). The normal 95 % reference range for the right auricular parameters was put forward. The right auricular parameters had a good correlation with the right atrium volume, aortic diameter, the body weight, height, and body surface area but a bad correlation with the vertebral body height. Significantly (P < 0.05) greater values were found in the normal angle and distance in subjects below than over 40 years of age. No other significant (P > 0.05) difference existed in the other right auricular parameters.

CONCLUSION

Quantitative measurements of the right auricle can help us get a good understanding of the right auricular morphology and its relationship with surrounding structures and are helpful for cardiac interventions of electrophysiology and radiofrequency ablation.

Non-vitamin K antagonist oral anticoagulants versus warfarin for cardioversion of atrial fibrillation in clinical practice: A single-center experience

Background

Anticoagulation therapy with the vitamin K antagonist (VKA) warfarin has been demonstrated to reduce thromboembolic risk after electrical cardioversion (ECV). However, data concerning ECV with non-VKA oral anticoagulants (NOACs) is limited. The objective of this study was to determine the efficacy and safety of NOACs in patients undergoing ECV in a real-world clinical practice at a single center in Japan.

Methods

We retrospectively analyzed the data of 406 consecutive patients who underwent ECV for atrial fibrillation (AF) or flutter under anticoagulation with one of the three NOACs (n=149) or with a VKA (n=257).

Results

The CHADS2 and HAS-BLED scores were significantly higher in the VKA group, whereas the NOACs group had a tendency toward greater spontaneous echo contrast grades. After ECV, ischemic stroke occurred in three patients of the VKA group and one patient in the NOAC group, all of whom had persistent AF, indicating no significant difference in the thromboembolic event rate within 30 days following ECV. No other thromboembolic events, major bleeding, or death occurred in either group. Among the NOAC and VKA patients in whom we newly introduced an oral anticoagulant to perform ECV, the number of days leading to ECV was significantly lesser for the NOAC patients.

Conclusion

NOACs may be used as an alternative to VKAs for ECV and may allow prompt ECV in clinical practices.

Impact of Additional Transthoracic Electrical Cardioversion on Cardiac Function and Atrial Fibrillation Recurrence in Patients with Persistent Atrial Fibrillation Who Underwent Radiofrequency Catheter Ablation

Backgrounds and Objective. During the procession of radiofrequency catheter ablation (RFCA) in persistent atrial fibrillation (AF), transthoracic electrical cardioversion (ECV) is required to terminate AF. The purpose of this study was to determine the impact of additional ECV on cardiac function and recurrence of AF. Methods and Results. Persistent AF patients received extensive encircling pulmonary vein isolation (PVI) and additional line ablation. Patients were divided into two groups based on whether they need transthoracic electrical cardioversion to terminate AF: electrical cardioversion (ECV group) and nonelectrical cardioversion (NECV group). Among 111 subjects, 35 patients were returned to sinus rhythm after ablation by ECV (ECV group) and 76 patients had AF termination after the ablation processions (NECV group). During the 12-month follow-ups, the recurrence ratio of patients was comparable in ECV group (15/35) and NECV group (34/76) (44.14% versus 44.74%, P = 0.853). Although left atrial diameters (LAD) decreased significantly in both groups, there were no significant differences in LAD and left ventricular cardiac function between ECV group and NECV group. Conclusions. This study revealed that ECV has no significant impact on the maintenance of SR and the recovery of cardiac function. Therefore, ECV could be applied safely to recover SR during the procedure of catheter ablation of persistent atrial fibrillation.

The Efficacy and Safety of Oral Rivaroxaban in Patients with Non-Valvular Atrial Fibrillation Scheduled for Electrical Cardioversion

Objective Electrical cardioversion (EC) is associated with an increased risk of thrombotic events in patients with non-valvular atrial fibrillation (NVAF). Patients who experience AF for a period of >48 hours therefore require adequate anticoagulation therapy for at least 3 weeks before and 4 weeks after EC. While the guidelines address the management of vitamin K antagonists (VKAs), there are limited data on the use of novel oral anticoagulants (NOAC). One NOAC, rivaroxaban, has a rapid onset of action and might therefore shorten the time for which anti-coagulant treatment is required before a patient undergoes EC. Methods This study included 91 patients with NVAF of >48 hours in duration or in whom the time of onset was unknown who were undergoing EC after pretreatment with rivaroxaban. All of the patients were pretreated with rivaroxaban for at least 2 hours before EC and the same dose of rivaroxaban was prescribed for 4 weeks after EC. The primary endpoint was a successful EC without any thrombotic events or bleeding complications within 30 days after EC. The secondary endpoint was the time to EC. Results The mean age was 63±12 years and 70 of the 91 patients were male. The CHADS2 and HAS-BLED scores were 1.0±1.0 and 1.7±1.3, respectively. Although there were no thrombotic events, minor bleeding (gingival hemorrhage) occurred 20 days after the initiation of rivaroxaban treatment in one patient. The average time to EC was 11.9±11.1 days. Conclusion Rivaroxaban is safe and effective drug for NVAF patients who are scheduled for an EC. Furthermore, since VKAs take a substantial amount of time to establish adequate anticoagulation, pretreatment with rivaroxaban could shorten the time to the EC.

Cardioversion Of Atrial Fibrillation And Oral Anticoagulation

The risk of thromboembolic events is a major concern in cardioversion of atrial fibrillation. The vast majority of these events occur in the first week following cardioversion. Processes promoting thrombus formation occur early and thrombus may appear in the left atrium within 48 hours of atrial fibrillation. The risk of thromboembolic events also increases with the presence of stroke risk factors. Thus, the current guidelines recommend that also patients with acute atrial fibrillation should undergo cardioversion under cover of unfractionated or low-molecular weight heparin followed by oral anticoagulation for at least 4 weeks in patients at moderate-to-high risk for stroke. Delay of cardioversion < 12 hours from the symptom onset seems to cause a marked increase in the risk of stroke. Thus, short term anticoagulation should be considered also for patients with a low CHA₂DS₂VASc score if the delay to cardioversion is 12-48 hours.

Absence of left atrial stunning after cardioversion of recent-onset atrial fibrillation in patients at low-stroke risk

OBJECTIVE

The aim of the present study was to evaluate the presence and degree of spontaneous echo contrast (SEC) in the left atrium and of left atrial appendage (LAA) contractility before and after cardioversion (CV) in patients with recent-onset atrial fibrillation (AF).

METHODS

Our study included 56 patients divided into two groups: group 1, comprising 32 clinically stable patients who were admitted to the Emergency Department with less than or equal to 48 h duration AF, and who underwent transoesophageal echocardiography (TEE)-guided CV; and the control group (group 2), comprising 24 patients admitted to the Cardiological Department for elective TEE-guided CV of greater than 48 h AF. All patients underwent repeat TEE within 1 h after successful CV.

RESULTS

Patients with recent-onset AF (group 1) showed no thrombogenic milieu at baseline without any evidence of atrial stunning after successful CV. SEC mean grade (0-3 grading) was 0.09±0.3 versus 0.12±0.4 after CV (P=0.98), and LAA flow velocity was 60.7±19.4 versus 56.7±20.5 cm/s after CV (P=0.07). Group 2 patients showed a significantly higher degree of SEC compared with those in group 1 (0.09±0.3 vs. 0.66±0.7, P=0.0093) and significantly lower LAA flow velocities (60.7±19.4 vs. 32.5±12.4, P<0.0001), with significant worsening after successful CV (SEC degree: 0.66±0.9 vs. 1.37±0.9, P=0.0093; LAA flow velocity: 32.5±12.4 vs. 20.4±12.7 cm/s, P<0.0001).

CONCLUSION

The absence of thrombogenic milieu and of left atrial stunning after CV in patients with recent-onset AF favours early CV without anticoagulation, at least in patients with a low thromboembolic risk profile. These patients could be discharged earlier from urgent care.

The left atrial appendage: anatomy, function, and noninvasive evaluation

The left atrial appendage (LAA) is a finger-like extension originating from the main body of the left atrium. Atrial fibrillation (AF) is the most common clinically important cardiac arrhythmia, occurring in approximately 0.4% to 1% of the general population and increasing with age to >8% in those >80 years of age. In the presence of AF thrombus, formation often occurs within the LAA because of reduced contractility and stasis; thus, attention should be given to the LAA when evaluating and assessing patients with AF to determine the risk for cardioembolic complications. It is clinically important to understand LAA anatomy and function. It is also critical to choose the optimal imaging techniques to identify or exclude LAA thrombi in the setting of AF, before cardioversion, and with current and emerging transcatheter therapies, which include mitral balloon valvuloplasty, pulmonary vein isolation, MitraClip (Abbott Laboratories, Abbott Park, Illinois) valve repair, and the implantation of LAA occlusion and exclusion devices. In this review, we present the current data regarding LAA anatomy, LAA function, and LAA imaging using the currently available noninvasive imaging modalities.

Quantitative Evaluation of the Substantially Variable Morphology and Function of the Left Atrial Appendage and Its Relation with Adjacent Structures

Objective

To investigate quantitatively the morphology, anatomy and function of the left atrial appendage (LAA) and its relation with adjacent structures.

Materials and Methods

A total of 860 patients (533 men, 62.0%, age 55.9±10.4 year) who had cardiac multidetector computed tomography angiography from May to October 2012 were enrolled for analysis.

Results

Seven types and 6 subtypes of LAA morphology were found with Type 2 being the most prevalent. Type 5 was more significantly (P<0.05) present in women (8.0%) than in men (4.2%). LAA orifice was oval in 81.5%, triangular in 7.3%, semicircular in 4%, water drop-like in 3.2%, round in 2.4% and foot-like in 1.6%. The LAA orifice had a significantly greater (P<0.01) major axis in men (24.79±3.81) than in women (22.68±4.07). The LAA orifice long axis was significantly (P<0.05) positively correlated with the height, weight and surface area of the patient. The LAA morphology parameters displayed strong positive correlation with the left atrium volume, aortic cross area long axis or LSPV long axis but poor correlation with the height, weight, surface area and vertebral body height of the patients. Four types of LAA ridge were identified: AI, AII, B and C with the distribution of 17.6%, 69.9%, 5.9% and 6.6%, respectively. The LAA had a significantly (P<0.05) greater distance from its orifice to the mitral ring in women than in men. The LAA had two filling and two emptying processes with the greatest volume at 45% phase but the least volume at 5% phase. The LAA maximal, minimal and emptying volumes were all significantly (P<0.05) positively correlated with the body height, weight and surface area, whereas the LAA ejection fraction had an inverse correlation with the LAA minimal volume but no correlation with the maximal volume.

Conclusion

The LAA has substantially variable morphologies and relation with the adjacent structures, which may be helpful in guiding the LAA trans-catheter occlusion or catheter ablation procedures.

Left atrial thrombus formation and resolution during dabigatran therapy: A Japanese Heart Rhythm Society report

BACKGROUND

Protocols on the use of novel oral anticoagulants for stroke prevention in patients with atrial fibrillation (AF) undergoing electrical cardioversion (ECV) are lacking.

AIM

The study was aimed at evaluating the efficacy of dabigatran (Dabi) treatment in preventing peri-ECV stroke.

METHODS

A retrospective survey of the incidence and fate of left atrial (LA) thrombus during Dabi therapy in patients with AF was conducted between December 2012 and January 2013 by the Japanese Heart Rhythm Society.

RESULTS

A total of 198 patients from 299 institutions underwent transesophageal echocardiography (TEE) to rule out LA thrombus before ECV. Of these, LA thrombus was found in eight patients (4%), who tended to be older (67.3 vs. 61.3 years, p=0.175), had higher CHADS2 scores (1.88 vs. 0.95, p=0.058), and a higher prevalence of prior stroke or transient ischemic attack (22.2% vs. 2.6%, p=0.034) than those without LA thrombus. Of the eight patients with LA thrombus, one had LA thrombus during a Dabi 150 mg b.i.d treatment, whereas the remaining seven were receiving 110 mg b.i.d for 3 weeks or longer. In 6 of the 8 patients with LA thrombus, a second TEE was performed, revealing complete resolution of LA thrombus in five; among these five patients, one received Dabi dosage of 150 mg b.i.d unchanged, two received an increased dosage from 110 mg to 150 mg b.i.d, and two were switched to warfarin. Two patients had a stroke 3 and 15 days after ECV, and one had a major large intestine bleeding episode during Dabi therapy.

CONCLUSIONS

LA thrombus developed in 4% of patients with AF receiving Dabi. Older patients with a higher CHADS2 score receiving a lower Dabi dosage were more likely to develop LA thrombus, which was resolved with a prolonged or increased dosage. A higher Dabi dosage may be more beneficial before ECV but prospective randomized studies would be needed to confirm these results.

Left atrial appendage exclusion for atrial fibrillation

Percutaneous left atrial appendage (LAA) closure is being increasingly used as a treatment strategy to prevent stroke in patients with atrial fibrillation (AF) who have contraindications to anticoagulants. Several approaches and devices have been developed in the last few years, each with their own unique set of advantages and disadvantages. In this article, the published studies on surgical and percutaneous approaches to LAA closure are reviewed, focusing on stroke mechanisms in AF, LAA structure and function relevant to stroke prevention, practical differences in procedural approach, and clinical considerations surrounding management.

Global left atrial strain in the prediction of sinus rhythm maintenance after catheter ablation for atrial fibrillation

BACKGROUND

Left atrial (LA) strain is a sensitive measure of LA mechanics. However, its relationship with rhythm outcomes after catheter ablation in patients with atrial fibrillation (AF) is not well established. The aim of this study was to evaluate whether baseline LA global longitudinal strain (LAε) predicts rhythm outcomes in patients who undergo catheter ablation for AF.

METHODS

In 256 patients with AF (paroxysmal, 204; persistent, 52), comprehensive echocardiography was performed with assessment of LAε by using Velocity Vector Imaging to calculate average strain values from apical four- and two-chamber views before ablation (median, 41 days; interquartile range, 1-95 days).

RESULTS

After a median of 8.0 months (interquartile range, 4.0-23.3 months) of follow-up, 149 patients (58%) had maintained sinus rhythm and 107 patients (42%) had recurrence of AF. In our study cohort (mean age 59 ± 11 years; mean left ventricular ejection fraction, 58 ± 10%), impaired total LAε (LAεtotal) was associated with greater left ventricular mass index (r = -0.245, P < .001) and worsening left ventricular diastolic function (ratio of transmitral flow peak early diastolic velocity to peak early diastolic velocity of the mitral annulus: r = -0.357, P < .001; maximal LA volume index: r = -0.393, P < .001). Patients with LAεtotal < 23.2% showed a higher incidence of AF recurrence compared with patients with LAεtotal ≥ 23.2% (log-rank P < .001). In multivariate Cox proportional-hazards analysis, LAεtotal was independently related to rhythm outcomes (hazard ratio, 0.944; 95% confidence interval, 0.915-0.975; P < .001) after AF ablation. Moreover, LAεtotal provided incremental predictive value for rhythm outcomes over clinical features (increment in global χ(2) = 14.63, P < .001).

CONCLUSIONS

In patients with AF, baseline LAεtotal was associated with rhythm outcome after catheter ablation.