Restoration of sinus rhythm results in early and late improvements in the functional reserve of the heart following direct current cardioversion of persistent AF: FRESH-AF

Exercise echocardiography to assess left atrial function in patients with symptomatic AF

Background

Left atrial (LA) function contributes to the augmentation of cardiac output during exercise. However, LA response to exercise in patients with atrial fibrillation (AF) is unknown. We explored the LA mechanical response to exercise and the association between LA dysfunction and exercise intolerance.

Methods

We recruited consecutive patients with symptomatic AF and preserved left ventricular ejection fraction (LVEF). Participants underwent exercise echocardiography and cardiopulmonary exercise testing (CPET). Two-dimensional and speckle-tracking echocardiography were performed to assess LA function at rest and during exercise. Participants were grouped according to presenting rhythm (AF vs sinus rhythm). The relationship between LA function and cardiorespiratory fitness in patients maintaining SR was assessed using linear regression.

Results

Of 177 consecutive symptomatic AF patients awaiting AF ablation, 105 met inclusion criteria; 31 (29.5 %) presented in AF whilst 74 (70.5 %) presented in SR. Patients in SR augmented LA function from rest to exercise, increasing LA emptying fraction (LAEF) and LA reservoir strain. In contrast, patients in AF demonstrated reduced LAEF and reservoir strain at rest, with failure to augment either parameter during exercise. This was associated with reduced VO2Peak compared to those in SR (18.4 ± 5.6 vs 22.5 ± 7.7 ml/kg/min, p = 0.003). In patients maintaining SR, LAEF and reservoir strain at rest and during exercise were associated with VO2Peak, independent of LV function.

Conclusion

The maintenance of SR in patients with AF is associated with greater LA reservoir function at rest and greater augmentation with exercise compared to patients in AF. In patients in SR, reduced LA function is associated with reduced exercise tolerance, independent of LV function.

A Prognostic Score To Predict Atrial fibrillation Recurrence After External Electrical Cardioversion-SLAC Score

INTRODUCTION

Atrial fibrillation (AF) recurrence after a successful external electrical cardioversion (ECV) is common. Assessing an individual's risk of AF recurrence is a critical part of the treatment plan. We aimed to develop a prognostic prediction score to predict AF recurrence in AF patients who underwent successful ECV.

METHODS

A retrospective cohort study that included AF patients who underwent successful ECV was conducted with a primary outcome of AF recurrence at 6 months. Logistic regression analysis was done to identify variables, and a prognostic prediction score was created and internally validated.

RESULTS

Four prognostic predictors were identified, including the type of AF, persistent AF (1 point) and long-standing persistent AF (4 points), previous cardioversion (1 point), stroke/transient ischemic attack (3 points), and left atrial volume index ≥40 mL/m 2 (6 points). The total score of 14 was further divided into 3 risk groups; low-risk (0-2 points), moderate-risk (3-7 points), and high-risk (8-14 points). The positive likelihood ratio for a moderate-risk patient was 2.08 (95% CI, 1.64-2.63) and for a high-risk patient was 7.90 (95% CI, 2.48-25.17). The score showed good discrimination power with the c-statistic of 0.74 (95% CI, 0.69-0.79).

CONCLUSIONS

A simple prognostic prediction score for AF recurrence after successful ECV was created with a promising internally validated discrimination power. An external assessment of its usefulness as a tool to identify patients with low, moderate, and high risk for AF recurrence is warranted.

Incidence and Determinants of Spontaneous Cardioversion of Early Onset Symptomatic Atrial Fibrillation

Atrial fibrillation (AF) is the most frequent chronic arrhythmia worldwide, and it is associated with significant morbidity and mortality, making it a considerable burden both to patients and the healthcare system. Nowadays, an early attempt to restore sinus rhythm in acute symptomatic AF through electrical or pharmacological cardioversion is the most common approach in the Emergency Department (ED). However, considering the high percentage of spontaneous cardioversion of paroxysmal AF reported by many studies, this approach may not be the ideal choice for all patients. In this manuscript we performed a review of the most relevant studies found in literature with the aim of identifying the main determinants of spontaneous cardioversion, focusing on those easy to detect in the ED. We have found that the most relevant predictors of spontaneous cardioversion are the absence of Heart Failure (HF), a small atrial size, recent-onset AF, rapid Atrial Fibrillatory Rate and the relationship between a previous AF episode and Heart Rate/Blood Pressure. A number of those are utilized, along with other easily determined parameters, in the recently developed "ReSinus" score which predicts the likelihood of AF spontaneous cardioversion. Such identification may help the physician decide whether immediate cardioversion is necessary, or whether to adopt a "watch-and-wait" strategy in the presence of spontaneous cardioversion determinants.

Comparison of dronedarone vs. flecainide in the maintenance of sinus rhythm, following electrocardioversion in adults with persistent atrial fibrillation: a systematic review and meta-analysis

AIMS

To compare flecainide and dronedarone for sinus rhythm (SR) maintenance following electrocardioversion of persistent atrial fibrillation (AF), in patients with minimal or no structural heart disease.

METHODS AND RESULTS

A systematic search of publications using EMBASE, CENTRAL, CINAHL, and MEDLINE (1989-2019), identified a total of 595 articles. No limitations were applied. Nine articles met the inclusion criteria [five randomized controlled trials (RCTs) and four cohort studies], encompassing 1349 persistent AF candidates. Two retrospective studies compared flecainide with dronedarone, indicating a 6% reduced risk of AF recurrence with flecainide; however, results were not statistically significant [risk ratio (RR) 0.94, 95% confidence interval (CI) 0.71-1.24; P = 0.66]. One RCT compared dronedarone to placebo, demonstrating a 28% reduced risk of AF recurrence at 6 months (RR 0.72, 95% CI 0.58-0.90; P = 0.004). Two RCTs compare flecainide to placebo, when a 16% decreased risk of AF recurrence at 6-12 months was indicated; however, these results were not statistically significant (RR 0.84, 95% CI 0.66-1.07; P = 0.16). Within a 6- to 12-month follow-up period, a combined recurrence rate of AF was examined, in which flecainide and dronedarone maintained SR in 50% and 42%, respectively. Four articles satisfied quality appraisal, one of which focused on flecainide data.

CONCLUSION

Dronedarone and flecainide displayed similar efficacy in maintaining SR in patients following electrocardioversion for persistent AF. The SR maintenance was numerically but not statistically significant in the flecainide group. Side effects uncovered similar pro-arrhythmic activity. However, in light of the deficiency of volume and quality of available evidence, the writer acknowledges the requirement for future research.

Benefits of Rhythm Control and Rate Control in Recent-onset Atrial Fibrillation: The HERMES-AF Study

BACKGROUND

Although rhythm control has failed to demonstrate long-term benefits over rate control in longstanding episodes of atrial fibrillation (AF), there is little evidence concerning recent-onset ones. We analyzed the benefits of rhythm and rate control in terms of symptoms alleviation and need for hospital admission in patients with recent-onset AF.

METHODS

This was a multicenter, observational, cross-sectional study with prospective standardized data collection carried out in 124 emergency departments (EDs). Clinical variables, treatment effectiveness, and outcomes (control of symptoms, final disposition) were analyzed in stable patients with recent-onset AF consulting for AF-related symptoms.

RESULTS

Of 421 patients included, rhythm control was chosen in 352 patients (83.6%), a global effectiveness of 84%. Rate control was performed in 69 patients (16.4%) and was achieved in 67 (97%) of them. Control of symptoms was achieved in 396 (94.1%) patients and was associated with a heart rate after treatment ≤ 110 beats/min (odds ratio [OR] = 14.346, 95% confidence interval [CI] = 3.90 to 52.70, p < 0.001) and a rhythm control strategy (OR = 2.78, 95% CI = 1.02 to 7.61, p = 0.046). Sixty patients (14.2%) were admitted: discharge was associated with a rhythm control strategy (OR = 2.22, 95% CI = 1.20-4.60, p = 0.031) and admission was associated with a heart rate > 110 beats/min after treatment (OR = 29.71, 95% CI = 7.19 to 123.07, p < 0.001) and acute heart failure (OR = 9.45, 95% CI = 2.91 to 30.65, p < 0.001).

CONCLUSION

In our study, recent-onset AF patients in whom rhythm control was attempted in the ED had a high rate of symptoms' alleviation and a reduced rate of hospital admissions.

Ibutilide Effectiveness and Safety in the Cardioversion of Atrial Fibrillation and Flutter in the Community Emergency Department

STUDY OBJECTIVE

Little is known about the use of ibutilide for cardioversion in atrial fibrillation and flutter outside of clinical trials. We seek to describe patient characteristics, ibutilide administration patterns, cardioversion rates, and adverse outcomes in the community emergency department (ED) setting. We also evaluate potential predictors of cardioversion success.

METHODS

Using a retrospective cohort of adults who received ibutilide in 21 community EDs between January 2009 and June 2015, we gathered demographic and clinical variables from electronic health records and structured manual chart review. We calculated rates of cardioversion and frequency of ventricular tachycardia within 4 hours and estimated adjusted odds ratios (aOR) in a multivariate regression model for potential predictors of cardioversion.

RESULTS

Among 361 patients, the median age was 61 years (interquartile range 53 to 71 years) and most had recent-onset atrial fibrillation and flutter (98.1%). Five percent of the cohort had a history of heart failure. The initial QTc interval was prolonged (>480 ms) in 29.4% of patients, and 3.1% were hypokalemic (<3.5 mEq/L). The mean ibutilide dose was 1.5 mg (SD 0.5 mg) and the rate of ibutilide-related cardioversion within 4 hours was 54.8% (95% confidence interval [CI] 49.6% to 60.1%), 50.5% for atrial fibrillation and 75.0% for atrial flutter. Two patients experienced ventricular tachycardia (0.6%), both during their second ibutilide infusion. Age (in decades) (aOR 1.3; 95% CI 1.1 to 1.5), atrial flutter (versus atrial fibrillation) (aOR 2.7; 95% CI 1.4 to 5.1), and no history of atrial fibrillation and flutter (aOR 2.0; 95% CI 1.2 to 3.1) were associated with cardioversion.

CONCLUSION

The effectiveness and safety of ibutilide in this community ED setting were consistent with clinical trial results despite less stringent patient selection criteria.