Transesophageal Echocardiography and Cardioversion Trends in Patients with Atrial Fibrillation: A 10-Year Survey

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 Appendage Closure for Patients with Cerebral Amyloid Angiopathy and Atrial Fibrillation: the LAA-CAA Cohort

Anticoagulation increases the risk of intracerebral hemorrhage (ICH) in patients with cerebral amyloid angiopathy (CAA), so the management of stroke-risk in patients with both atrial fibrillation (AF) and CAA is controversial. Advances in left atrial appendage closure (LAAC) techniques provide a stroke-risk-reduction option which avoids long-term oral anticoagulation (OAC). We aimed to evaluate the safety of this intervention in patients with CAA. This is an observational cohort study of patients with severe CAA (with or without ICH) and AF who were treated with LAA closure. The Watchman™ and Amulet® LAAC devices and Lariat procedure or open surgical closure of the LAA were all considered acceptable means of closure. Patients with symptomatic ICH and those naïve to anticoagulation were placed on clopidogrel and/or aspirin for 6 weeks after the procedure; patients who previously tolerated anticoagulation remained on warfarin or a DOAC for 6 weeks post-procedure. All anticoagulation therapy was discontinued after confirmation of LAAC. All patients had aggressively optimized blood pressure and fall precautions in addition to surgical intervention. Safety, tolerability, stroke, and hemorrhage rates were documented. Twenty-six patients with a mean CHA₂DS₂-VASc score of 4.6 were treated, 13 with a history of symptomatic lobar hemorrhage and 13 without. All patients who completed LAAC tolerated the device implantation. There were no documented ischemic strokes or symptomatic ICH during the 30 days after device implantation. Patients were followed for an average of 25 months. One patient who underwent Lariat LAAC had an ischemic stroke in follow-up, but recovered well; there were no other thromboemboli in this cohort. This cohort study provides evidence that LAAC appears to be a safe and tolerable treatment to reduce stroke risk in patients with CAA. Because of the small size of the cohort and relatively short follow-up, the efficacy for stroke and ICH prevention is not conclusive, but the preliminary results are encouraging. LAA closure may be a good alternative to anticoagulation in patients with CAA and atrial fibrillation.

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.

Effectiveness and Safety of an Independently Run Nurse Practitioner Outpatient Cardioversion Program (2009 to 2014)

Sustained growth in the arrhythmia population at Stanford Health Care led to an independent nurse practitioner-run outpatient direct current cardioversion (DCCV) program in 2012. DCCVs performed by a medical doctor, a nurse practitioner under supervision, or nurse practitioners from 2009 to 2014 were compared for safety and efficacy. A retrospective review of the electronic medical records system (Epic) was performed on biodemographic data, cardiovascular risk factors, medication history, procedural data, and DCCV outcomes. A total of 869 DCCVs were performed on 557 outpatients. Subjects were largely men with an average age of 65 years; 1/3 were obese; most had atrial fibrillation; and majority of subjects were on warfarin. The success rate of the DCCVs was 93.4% (812 of 869) with no differences among the groups. There were no short-term complications: stroke, myocardial infarction, or death. The length of stay was shortest in the NP group compared to the other groups (p <0.001). In conclusion, the success rate of DCCV in all groups was extremely high, and there were no complications in any of the DCCV groups.

Transesophageal Echocardiography in Atrial Fibrillation

Transesophageal echocardiography (TEE) plays an important role in atrial fibrillation (AF), mainly to detect the presence of left atrial appendage (LAA) thrombus. It is useful in direct current cardioversion (DCC) guidance and for AF ablation and LAA occlusion. With the increasing number of patients affected by AF, the use of TEE will grow and become an important screening modality for LAA thrombus. Future direction includes broader multi-institutional use; further tools to risk stratify patients; and the use of a new spectrum of oral anticoagulants and their cost-effectiveness in patients with AF undergoing DCC, AF ablation, and LAA occlusion.

Evaluation of left atrial deformation to predict left atrial stasis in patients with non-valvular atrial fibrillation - a pilot-study

BACKGROUND

Speckle tracking-derived strain and strain rate are recently available parameters to assess left atrial (LA) deformation. We hypothesized that such new parameters could be of interest to evaluate the risk of LA stasis among patients with atrial fibrillation (AF).

METHODS

Single-centre study enrolling all patients with non-valvular AF lasting longer than 48 hours for whom no therapeutic anticoagulation was given in the preceding 3 weeks and who were assessed through transesophageal and transthoracic echocardiogram during a 6 month time interval. LA deformation was assessed by transthoracic echocardiogram through speckle tracking analysis, whereas LA stasis parameters were sought on transesophageal echocardiogram.

RESULTS

Among the 82 assessed patients, LA appendage thrombi or sludge were found in 16 (19.5%). A moderate positive correlation was found between peak positive strain rate and maximum emptying velocity (r = 0.589; P <0.001) and peak positive strain rate and maximum filling velocity of the LA appendage (r = 0.651; P <0.001). Peak negative strain rate was also found to be associated with both maximum emptying velocity (r = -0.513; P <0.001) and maximum filling velocity of the LAA (r = -0.552; P <0.001). AF duration, peak negative strain rate and time-to-peak positive strain were independent predictors of LAA thrombi or sludge on multivariate analysis logistic regression. The area under the curve for the estimated probabilities using the obtained logistic regression model was 0.89 (95%CI 0.81-0.96; P <0.001).

CONCLUSION

Our findings suggest that LA mechanical dysfunction assessed through speckle tracking may be of interest to predict LA stasis in the setting of AF.