Title
Author
DOI
Article Type
Special Issue
Volume
Issue
Factors related to the success or failure of cardioversion in atrial fibrillation and emergency department revisit according to restoration of sinus rhythm: analysis of the URGFAICS cohort
1Emergency Department, Hospital Universitari de Bellvitge, 08907 Barcelona, Spain
2Emergency Department, Hospital Arnau de Vilanova, 25007 Lleida, Spain
3Emergency Department, Hospital de Viladecans, 08840 Barcelona, Spain
4Emergency Department, Hospital Universitari Joan XXIII de Tarragona, 43001 Tarragona, Spain
5Emergency Department, Hospital Universitari Germans Trias i Pujol de Badalona, 08916 Barcelona, Spain
*Corresponding Author(s):jjacob@bellvitgehospital.cat (Javier Jacob)
| History | Submitted: 17 December 2021 | Accepted: 12 January 2022 | Published: 08 March 2023 |
| Copyright: | ©2023 The Author(s). Published by MRE Press. |
Rhythm control in atrial fibrillation (AF) improves haemodynamic status and symptoms. However, there are few data related to revisit of patients who have undergone cardioversion in the Emergency Department (ED). The aim of the study was to compare ED revisit within 30 days according to the effectiveness of cardioversion and analyse the variables related to effective cardioversion. We undertook a multicentre, observational, cohort study with a 30-day follow-up. Older adults with AF presenting to 5 EDs in Spain and undergoing cardioversion were included. The primary endpoint was revisit to the ED within 30 days, and univariate and multivariate analyses were carried out according to the effectiveness of cardioversion. We enrolled 336 patients who underwent cardioversion in the ED. Following the index visit, 7.4% revisited the ED within 30 days, with no differences with respect to the effectiveness of cardioversion (hazard ratio: 0.87; 95% confidence interval (CI) 0.31–2.43). In the multivariate study, AF lasting <48 hours was related to more effective cardioversion (adjusted odds ratio (aOR): 2.14; 95% CI 1.16–3.59) while the use of amiodarone (aOR: 0.52; 95% CI 0.27–0.99) and digoxin in ED (aOR: 0.28; 95% CI 0.13–0.66) was related to less effective cardioversion. In patients with AF undergoing a rhythm control strategy in the ED, the absence of restoration of sinus rhythm was not associated with a greater frequency of 30-day ED revisit.
Cite this article
Irene Cabello, Javier Jacob, Oriol Yuguero, María Arranz, Jorge-Alexis Guzmán, Anna Moreno, Paloma Francés, Julia Santos, Anna Esquerrà, Álvaro Zarauza, Josep-María Mòdol, on behalf of URGFAICS Research Group. Factors related to the success or failure of cardioversion in atrial fibrillation and emergency department revisit according to restoration of sinus rhythm: analysis of the URGFAICS cohort. Signa Vitae. 2023; 19(2): 39-47. doi: 10.22514/sv.2022.020
1. Introduction
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in adults worldwide [1]. The incidence and prevalence of AF are increasing, with significant associated morbidity, mortality, and costs, including a 2-fold increase in mortality and a 6-fold increase in the risk of stroke [2, 3, 4]. The progression of recent-onset AF (AF of less than 1 year duration) can be modified by an early rhythm control strategy, which provides better control of haemodynamic status and symptom management, reducing hospital stay and also allowing immediate return to normal activities [5, 6]. However, this strategy does not provide an advantage in survival over a rate-control strategy or in the prevention of stroke [7].
Acute presentation of AF is frequently managed in the emergency department (ED). In recent years, the high prevalence of AF in the ED has led to emergency physicians playing an increasingly more relevant role in the management of AF. The management of AF in the ED includes rapid assessment of the need for thromboembolic prophylaxis, the need to control the heart rate when elevated or symptomatic, and the possibility of achieving rhythm control in recent-onset AF or permanent AF in previously correctly anticoagulated patients. Reestablishment of sinus rhythm (SR) can be performed by direct current cardioversion (DCC) or by the administration of antiarrhythmic drugs. DCC has shown to be more effective than pharmacological cardioversion (PhC) [8, 9]. However, long-term maintenance of SR remains a challenge. Some studies have reported that recurrence of AF is lower when cardioversion is performed early [10, 11] but there are few data on ED revisit related to the restoration of SR. In a previous study, ED revisit after discharge for another episode of AF was not high but was related to a worse perceived quality of life [12, 13]. ED revisit is mainly due to the reappearance of symptoms that previously led to consultation, especially the reappearance of palpitations [13].
We hypothesised that the absence of restoration of SR may be associated with greater ED revisit related to the previous AF episode. Therefore, the aim of this study was to compare ED revisit within 30 days after discharge according to the effectiveness of cardioversion in patients consulting for AF. We also analysed the variables related to effective cardioversion.
2. Methods
2.1 Study design and setting
This was a secondary analysis of the URGFAICS (Atrial Fibrillation in the Emergency Department Institut Català Salut) registry, which is a multipurpose, analytic, non-interventionist, multicentre Spanish registry with a prospective 30-day follow-up [13]. We included all consecutive patients diagnosed with AF in the EDs of five public hospitals of the Catalan health institute: hospital universitari Joan XXIII de Tarragona, hospital universitari Arnau de Vilanova de Lleida, hospital universitari de Bellvitge de l’Hospitalet de Llobregat, hospital universitari Germans Trias I Pujol de Badalona and hospital de Viladecans. Patients were consecutively included from September 2016 to February 2017. Eligible patients were all men and women 18 years of age or older who consulted to the ED with symptoms related to AF or the casual finding of AF on electrocardiogram (ECG) performed 12 hours prior to consultation. The diagnosis of AF was performed by a 12-lead ECG recorded at admission following to the diagnostic criteria of the last European cardiology society guidelines, with the presence of irregular RR intervals and non-discernible, distinct P waves [9]. Exclusion criteria were age younger than 18 years, an electrical rhythm other than AF and patients who did not provide informed consent. To achieve consecutive inclusion, the research team consisted of emergency physicians responsible for the conduct of the study who performed the initial recruitment and requested informed consent from the patients in each participating centre. Patients were consecutively included by emergency physicians responsible for carrying out the study after having obtained informed consent from the patients in the participating centres. Although each site had more than one investigator, all cases were confirmed by the principal investigator of each centre to ensure that the patients met the diagnostic criteria of AF, fulfilled all the inclusion and none of exclusion criteria. Investigators were not blinded to the objective of the study. To perform this analysis, only patients in whom DCC or PhC was performed were selected independently of its effectiveness. The decision to perform cardioversion depended on the attending physician, following the recommendations established at the time of the study [9].
Forty-eight variables were retrospectively extracted from medical records including age, male sex, comorbidities, long-term treatments at home, duration of the episode from the onset of symptoms to ED visit, clinical data, thrombotic risk, vital signs, ED pharmacologic treatment, type of cardioversion and treatment at discharge. Symptoms related to AF were those described in the modified European Heart Rhythm Association (EHRA) scale and the Canadian Cardiovascular Society Severity of Atrial Fibrillation (CCS-SAF) scale [12, 14].
The main outcome was 30-day revisit ED after the index episode, and the main predictor of interest was the success of cardioversion. The reason for the ED revisit had to be related to the AF of the index episode. The principal investigator of each centre performed the 30-day follow-up by consulting the hospital clinical history or by telephone call to the patient. For the analysis of ED revisit, only patients directly discharged from the ED were included.
2.2 Data analysis
Categorical variables are expressed as absolute and relative frequencies, and continuous data are presented as means with standard deviation (SD) or, if not normally distributed, as median, and interquartile range. For comparisons, the Chi-square test was used for the qualitative variables (or the Fisher exact test in 2 × 2 tables when the expected values were less than 5), and the student’s t test for independent measures was used for the quantitative variables, if the distribution did not affect the principle of normality (analysed using Kolmogorov-Smirnov test), or using the nonparametric Mann-Whitney test if affected.
To study the variables associated with the cardioversion success, the variables with significant differences between groups in the bivariate analysis were introduced into logistic regression (without interaction terms) with checks for nonlinearity and forward stepwise variable selection, with an entry criterion of a p value < 0.20. The resulting variables were expressed as odds ratio (OR) with the 95% confidence interval (CI).
The primary outcome was 30-day revisit to the ED depending on the success of cardioversion. Survival curves were constructed using the Kaplan-Meier model. Global differences between the different survival curves were determined using log-rank statistics. The group achieving cardioversion success was used as the reference group. The effect of successful cardioversion on 30-day revisit was expressed as crude hazard ratios (HRs), with 95% CI, and then the HR was adjusted for all potential confounding factors (p < 0.20), using direct Cox regression analysis. Differences were considered statistically significant with a p value < 0.05 or when the 95% CI of the OR or the HR excluded the value of 1. Secondary outcomes were the analysis of the variables related to effective cardioversion. The IBM SPSS Statistics Version 24.0 (IBM, Chicago, Il, USA) was used for the statistical analyses.
3. Results
A total of 1199 patients with AF who consulted to the ED were enrolled in the URGFAICS study. Of these, 372 (31%) patients underwent cardioversion, constituting the study group. We subsequently excluded patients who required hospitalisation (n = 36), and therefore, 336 patients who were discharged home were finally included in the main objective sub-study group (Fig. 1). Cardioversion, either electrical or pharmacological, was effective in 254 patients (68.3%). A total of 258 patients (69.4%) underwent pharmacological cardioversion, 59 received DCC (15.9%) and 57 (15.3%) underwent both. Table 1 shows the demographic data and characteristics of the study group and the univariate analysis according to whether cardioversion was effective or not, while Table 2 shows the clinical data and ED treatment. When comparing the effectiveness of cardioversion, univariate analysis showed failure to achieve cardioversion to be significantly related to the presence of a greater number of comorbidities. Patients undergoing cardioversion with AF of less than 48 hours more readily converted to SR (p < 0.001). Cardioversion was more effective in patients attended for palpitations and less effective in those attended for shortness of breath. The factors independently associated with successful or unsuccessful cardioversion after multivariate adjustment are presented in Table 3. AF lasting less than 48 hours was related to successful cardioversion (adjusted OR 2.14 (1.16–3.59); p = 0.015), while the use of amiodarone (adjusted OR: 0.52; 95% CI 0.27–0.99) and digoxin in ED (adjusted OR: 0.28; 95% CI 0.13–0.66) was related to unsuccessful cardioversion. Twenty-five patients (7.4%) presenting AF in the ECG revisited the ED revisit within 30 days. There were no differences when compared with the effectiveness of cardioversion. These results are shown in Fig. 2 with the means of survival curves for ED revisit within 30 days based on the effectiveness of cardioversion in Fig. 2A (unadjusted HR 1.18 (95% CI 0.51–2.74); p = 0.694) and Fig. 2B (adjusted HR 1.17 (95% CI 0.40–3.40); p = 0.777).
Fig. 1.Patient inclusion flow chart.
| Total | Missing values | Effective CV | Non-effective CV | p-value | ||
| (N = 372) | n (%) | (N = 254) | (N = 118) | |||
| n (%) | n (%) | n (%) | ||||
| Demographic data | ||||||
| Age (years), Mean (SD) | 68.2 (14.1) | 0 (0.0) | 66.2 (13.5) | 72.4 (14.3) | <0.001 | |
| Age ≥75 years | 136 (36.6) | 0 (0.0) | 75 (29.5) | 61 (51.7) | <0.001 | |
| Male sex | 177 (47.6) | 0 (0.0) | 131 (51.6) | 46 (39.0) | 0.024 | |
| Comorbidities | ||||||
| Hypertension | 245 (65.9) | 0 (0.0) | 162 (63.8) | 83 (70.3) | 0.214 | |
| Diabetes | 74 (19.9) | 0 (0.0) | 53 (20.9) | 21 (17.8) | 0.490 | |
| Heart valve disease | 82 (22.0) | 0 (0.0) | 47 (18.5) | 35 (29.7) | 0.016 | |
| Previous heart failure | 66 (17.7) | 0 (0.0) | 36 (14.2) | 30 (25.4) | 0.008 | |
| Coronary artery disease | 54 (14.6) | 3 (0.8) | 30 (12.0) | 24 (20.3) | 0.034 | |
| Chronic renal failure | 57 (15.3) | 0 (0.0) | 31 (12.2) | 26 (22.0) | 0.014 | |
| Chronic obstructive pulmonary disease | 40 (10.8) | 0 (0.0) | 29 (11.4) | 11 (9.3) | 0.544 | |
| History of stroke | 27 (7.3) | 0 (0.0) | 13 (5.1) | 14 (11.9) | 0.020 | |
| Peripheral vascular disease | 25 (6.7) | 0 (0.0) | 11 (4.3) | 14 (11.9) | 0.007 | |
| History of thromboembolism | 9 (2.4) | 0 (0.0) | 5 (2.0) | 4 (3.4) | 0.473 | |
| Previous AF | 144 (38.7) | 0 (0.0) | 94 (37.0) | 50 (42.4) | 0.323 | |
| Home medications | ||||||
| Beta-blocker | 169 (45.4) | 0 (0.0) | 118 (46.5) | 51 (43.2) | 0.560 | |
| Calcium channel blockers | 63 (16.9) | 0 (0.0) | 34 (13.4) | 29 (24.6) | 0.007 | |
| Amiodarone | 36 (9.7) | 0 (0.0) | 21 (8.3) | 15 (12.7) | 0.177 | |
| Digoxin | 6 (1.6) | 0 (0.0) | 4 (1.6) | 2 (1.7) | 1.000 | |
| Antiarrhythmic Class Ic | 55 (14.8) | 0 (0.0) | 43 (16.9) | 12 (10.2) | 0.087 | |
| Dronedarone | 2 (0.5) | 0 (0.0) | 2 (0.8) | 0 (0.0) | 1.000 | |
| Oral anticoagulant | 168 (45.2) | 0 (0.0) | 110 (43.3) | 58 (49.2) | 0.292 | |
| Thrombotic risk | ||||||
| CHA2DS2-VASc ≥2 points | 275 (73.9) | 0 (0.0) | 179 (70.5) | 96 (81.4) | 0.026 | |
| CV—cardioversion; AF—atrial fibrillation; SD—standard deviation. |
| Total | Missing values | Effective CV | Non-effective CV | p-value | |||
| (N = 372) | n (%) | (N = 254) | (N = 118) | ||||
| n (%) | n (%) | n (%) | |||||
| Acute episode data | |||||||
| AF lasting ≤48 hours | 230 (61.8) | 0 (0.0) | 174 (68.5) | 56 (47.5) | <0.001 | ||
| Clinical data | |||||||
| Palpitations | 223 (59.9) | 0 (0.0) | 164 (64.6) | 59 (50.0) | 0.008 | ||
| Shortness of breath | 41 (11.0) | 0 (0.0) | 18 (7.1) | 23 (19.5) | <0.001 | ||
| Thoracic discomfort | 65 (17.5) | 0 (0.0) | 42 (16.5) | 23 (19.5) | 0.485 | ||
| Dizziness or similar1 | 30 (8.1) | 0 (0.0) | 16 (6.3) | 14 (11.9) | 0.067 | ||
| Casual find | 18 (4.8) | 0 (0.0) | 11 (4.3) | 7 (5.9) | 0.503 | ||
| Other symptoms2 | 20 (5.4) | 0 (0.0) | 12 (4.7) | 8 (6.8) | 0.413 | ||
| Vital signs | |||||||
| SBP (mmHg), Mean (SD) | 128.3 (24.9) | 13 (3.5) | 128.4 (25.6) | 128.2 (23.6) | 0.934 | ||
| DBP (mmHg), Mean (SD) | 79.3 (15.5) | 16(4.3) | 78.5 (15.6) | 80.9 (15.3) | 0.169 | ||
| Heart rate (bpm), Mean (SD) | 124.4 (29.0) | 0 (0.0) | 123.9 (29.1) | 125.5 (28.7) | 0.613 | ||
| Oxygen saturation (%), Mean (SD) | 97.4 (2.3) | 21 (5.6) | 97.5 (2.1) | 97.2 (2.6) | 0.294 | ||
| HR >110 bpm | 262 (70.4) | 0 (0.0) | 177 (69.7) | 85 (72.0) | 0.644 | ||
| SBP <90 mmHg | 18 (5.0) | 13 (3.5) | 15 (6.1) | 3 (2.7) | 0.165 | ||
| ED treatment | |||||||
| Digoxin | 60 (16.2) | 1 (0.3) | 22 (8.7) | 38 (32.2) | <0.001 | ||
| Amiodarone | 225 (60.5) | 0 (0.0) | 135 (53.1) | 90 (76.3) | <0.001 | ||
| Beta-blockers3 | 54 (14.5) | 0 (0.0) | 35 (13.8) | 19 (16.1) | 0.554 | ||
| Antiarrhythmic Class Ic | 87 (23.4) | 0 (0.0) | 63 (24.8) | 24 (20.3) | 0.344 | ||
| Calcium channel blockers | 3 (0.8) | 0 (0.0) | 3 (1.2) | 0 (0.0) | 0.555 | ||
| Vernakalant | 3 (0.8) | 0 (0.0) | 3 (1.2) | 0 (0.0) | 0.555 | ||
| Type of cardioversion | |||||||
| Pharmacological | 258 (69.4) | 0 (0.0) | 149 (58.7) | 109 (92.4) | <0.001 | ||
| DCC | 59 (15.9) | 0 (0.0) | 55 (21.7) | 4 (3.4) | <0.001 | ||
| Pharmacological and DCC | 57 (15.3) | 0 (0.0) | 52 (20.5) | 5 (4.2) | <0.001 | ||
| Discharge treatment | |||||||
| Anticoagulant begin4 | 93 (45.1) | 0 (0.0) | 67 (45.9) | 26 (43.3) | 0.738 | ||
| Antivitamin K agonist | 58 (28.2) | 0 (0.0) | 43 (29.5) | 15 (25.0) | |||
| Direct oral anticoagulant | 32 (15.5) | 0 (0.0) | 23 (15.8) | 9 (15.0) | |||
| Heparin | 3 (1.5) | 0 (0.0) | 1 (0.7) | 2 (3.3) | |||
| Digoxin | 10 (2.7) | 4 (1.1) | 1 (0.4) | 9 (7.8) | <0.001 | ||
| Amiodarone | 97 (26.4) | 5 (1.3) | 67 (26.7) | 30 (25.9) | 0.867 | ||
| Beta-blockers | 77 (20.9) | 4 (1.1) | 45 (17.9) | 32 (27.6) | 0.033 | ||
| Antiarrhythmic Class Ic | 37 (10.1) | 4 (1.1) | 29 (11.5) | 8 (6.9) | 0.172 | ||
| Calcium channel blockers | 6 (1.6) | 5 (1.3) | 4 (1.6) | 2 (1.7) | 1 | ||
| Follow-up data | |||||||
| 30-day revisit | 25 (7.4) | 0 (0.0) | 17 (7.1) | 8 (8.2) | 0.72 | ||
| (N = 372) | n (%) | (N = 254) | (N = 118) | ||||
| n (%) | n (%) | n (%) | |||||
| Symptoms of revisit5 | |||||||
| Palpitations | 17 (68.0) | 0 (0.0) | 11 (64.7) | 6 (75.0) | 1 | ||
| Thoracic discomfort | 8 (32.0) | 0 (0.0) | 6 (35.3) | 2 (25.0) | 1 | ||
| Shortness of breath | 2 (8.0) | 0 (0.0) | 2 (11.8) | 0 (0.0) | 1 | ||
| ECG in AF of 30-days revisit | 25 (7.4) | 0 (0.0) | 17 (7.1) | 8 (8.2) | 0.72 | ||
| CV—cardioversion; AF—atrial fibrillation; SD—standard deviation; ASA—acetyl-salicylic acid; SBP—systolic blood pressure; DBP—diastolic blood pressure; HR—heart rate; bpm—beats per minute; ED—emergency department; DCC—direct current cardioversion. 1Dizziness or similar: dizziness, pre-syncope, syncope, sensation of instability. 2Other symptoms: abdominal pain, sickness. 3IV beta-blockers: propranolol, esmolol. 4Calculation performed only for patients who did not receive previous anticoagulant treatment (n = 206). 5Analysis performed in patients who presented revisit at 30 days. The sum is greater than 100% because the same patient may present more than one symptom as a reason for reconsultation (n = 25). |
| Unadjusted OR (95% CI) | p-value | Adjusted OR (95% CI) | p-value | ||
| Demographic data | |||||
| Age ≥75 years | 0.35 (0.22–0.57) | <0.001 | 0.57 (0.29–1.12) | 0.102 | |
| Male | 1.67 (1.07–2.60) | 0.024 | 1.69 (0.95–3.00) | 0.075 | |
| Comorbidity | |||||
| Heart valve disease | 0.54 (0.33–0.89) | 0.016 | 0.78 (0.39–1.57) | 0.486 | |
| History of heart failure | 0.48 (0.28–0.84) | 0.008 | 0.74 (0.32–1.72) | 0.487 | |
| Coronary artery disease | 0.53 (0.30–0.96) | 0.034 | 0.52 (0.22–1.24) | 0.142 | |
| Chronic renal failure | 0.49 (0.28–0.87) | 0.014 | 1.10 (0.48–2.52) | 0.815 | |
| Stroke | 0.40 (0.18–0.88) | 0.02 | 0.75 (0.21–2.72) | 0.666 | |
| Peripheral vascular disease | 0.34 (0.15–0.77) | 0.007 | 0.34 (0.11–1.03) | 0.057 | |
| Home treatment | |||||
| Calcium channel blockers | 0.47 (0.27–0.83) | 0.007 | 0.57 (0.27–1.22) | 0.145 | |
| Acute episode data | |||||
| AF lasting ≤48 hours | 2.41 (1.54–3.77) | <0.001 | 2.14 (1.16–3.59) | 0.015 | |
| Clinical data | |||||
| Palpitations | 1.82 (1.17–2.84) | 0.008 | 0.63 (0.31–1.28) | 0.199 | |
| Shortness of breath | 0.32 (0.16–0.61) | <0.001 | 0.92 (0.31–2.71) | 0.879 | |
| ED treatment | |||||
| Digoxin | 0.20 (0.11–0.36) | <0.001 | 0.28 (0.13–0.60) | 0.001 | |
| Amiodarone | 0.35 (0.22–0.58) | <0.001 | 0.52 (0.27–0.99) | 0.050 | |
| AF—atrial fibrillation; SD—standard deviation; CV—cardioversion; OR: odds ratio; CI—confidence interval; ED—emergency department. Adjusted model: age ≥75 years, male, heart valve disease, history of heart failure, coronary artery disease, chronic renal failure, stroke, peripheral vascular disease, home treatment with calcium channel blockers, antiarrhythmic class Ⅰc or amiodarone; systolic blood pressure <90 mmHg in ED, AF lasting ≤48 hours, palpitations, shortness of breath, dizziness or similar (pre-syncope, syncope, sensation of instability), digoxin or amiodarone in ED. |
Fig. 2.Survival curves for ED revisit at 30 days for a new episode of AF according to the effectiveness of cardioversion (n = 336). (A) unadjusted HR; (B) adjusted HR. Adjustment made based on the following variables: age ≥75 years, gender, history of heart valve disease, previous heart failure, ischaemic heart disease, chronic renal failure, stroke, peripheral vascular disease; use of calcium blockers, amiodarone; duration of AF <48 hours, presence of palpitations, shortness of breath or dizziness; CHA2DS2-VASc ≥2 points, use of digoxin or amiodarone in the emergency department, use of digoxin or beta-blockers at discharge from the emergency department.
4. Discussion
The purpose of our study was to determine whether SR restoration was associated with early 30-day ED revisit in patients with AF. To do this, we compared a group of patients in whom cardioversion was effective with another group in whom cardioversion was ineffective, not considering the indication of cardioversion but rather the result of the procedure. The population in our study is representative of the majority of patients with AF described in other registries [15, 16, 17, 18, 19], with older patients (65 years of age or older) being the most prevalent. The usefulness of cardioversion in haemodynamically stable patients with AF has been studied by many groups. Several studies have demonstrated the safety and effectiveness of ED cardioversion, especially with DCC, reporting infrequent, transient adverse events irrespective of the method used [3, 8, 19, 20, 21]. Surprisingly, we observed no differences in ED revisit between the two groups according to the effectiveness of cardioversion. In our study, the overall percentage of revisit at 30 days was low (7.4%) compared with the 10.3% to 15.4% reported in previous studies [18, 19, 22]. Considering the few data available in relation to early ED revisit, it is difficult to establish whether our data are limited by the low-revisit rate. Several studies have compared a rhythm-control strategy versus a rate-control strategy, cardioversion by DCC versus PhC, or different class Ic antiarrhythmic drugs versus amiodarone [7, 19, 23, 24, 25]. However, to our knowledge no previous study has specifically compared discharge rhythm and 30-day ED revisit.
According to our results, SR restoration was not associated with early 30-day ED revisit in patients with AF. The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study, which included a total of 4060 patients, concluded that management of AF with a rhythm-control strategy offers no survival advantage compared with rate-control [7]. Neither did they find differences in the secondary endpoints, such as stroke or cardiac arrest. A recently published study also concluded that in patients presenting to the ED with recent-onset AF, a wait-and-see approach was not inferior to early cardioversion in achieving SR at 4 weeks [26]. These studies support our findings, concluding that early restoration of SR is not necessarily mandatory. These data do not invalidate the fact that successful cardioversion is feasible and safe in the ED. It has also been related to the occurrence of fewer adverse events, better haemodynamic status, and better symptom management [3, 7]. The latest guidelines support the use of rhythm control and based on the results of previous studies, DCC is probably the best option for achieving SR restoration [3, 9]. However, when SR restoration is not achieved for any reason, our data suggest that emergency physicians can safely discharge patients home provided that they are stable, rate control is achieved, and thromboprophylaxis is optimised.
A secondary aim of our study was to determine the variables associated with increased efficiency of cardioversion. Our data reflect an association between AF duration ≤48 hours and successful cardioversion. It is well known that patients with recent-onset AF respond much better to cardioversion [17]. In a recent analysis of the Hospital EmeRgency department Management Strategies of Atrial Fibrillation (HERMES-AF) cohort, the global effectiveness of a rhythm control strategy for achieving SR in patients with AF of short duration was 84%. Moreover, this strategy was associated with better control of AF symptoms and a lower need for hospitalisation [16].
The use of amiodarone and digoxin in the ED during the AF episode, which was related to non-effective cardioversion in our study, is indicated in patients with previous heart disease or in acute heart failure and may act as a confounding factor. Both drugs were still associated with non-effective cardioversion after the adjusted analysis with variables such as heart failure, coronary artery disease or heart valve disease. Calcium channel blockers and digoxin are drugs used for heart rate control and have no effect on rhythm control [27]. While amiodarone is frequently used in the ED, especially in patients in whom class Ⅰc drugs are contraindicated, its effect is slow [28]. The AVRO clinical assay, which compared vernakalant with amiodarone. Its use in ED is safe and effective revealed that while amiodarone only achieved restoration of SR in 22.6% of patients after 4 hours of treatment, its use in the ED is safe and effective [29, 30]. In another study comparing flecainide, propafenone and amiodarone, amiodarone achieved SR restoration in 30% of patients after 6 hours of infusion [25]. Although amiodarone is a class Ⅰ (level of evidence A) indication for patients with recent-onset AF and structural heart disease, we believe it is over-used in the ED and is scarcely effective.
This observational cohort study had several limitations, including the small number of patients undergoing cardioversion in the initial study group (31%). Nonetheless, in several previous registries, such as the Canadian registry or the GEFAUR-1 study, only 42% of all the eligible patients received rhythm control therapy [17, 18, 19]. Another limitation is that we reported patients who revisited the ED for a new episode of AF or symptoms related to AF, but we did not monitor the remaining patients with ECG, and therefore, the true incidence of recurrent asymptomatic AF at 30-days was likely underestimated. Additionally, the instructions given to patients in the index visit in regard to when to revisit the ED were not standardised among the emergency physicians from the different centres participating in the study, and thus, there may have been a hospital-dependent bias in revisit. On the other hand, another limitation was that we have no follow-up data related to ablation, which is a technique that should be evaluated in patients with AF. In our setting, the guidelines of the European Society of Cardiology are followed, and ED physicians evaluate the need for referral to an arrhythmia unit for a complete study and ablation, if indicated, in all AF cases [9]. We believe that the lack of data on ablation in our study did not affect the results since, in our country, this technique is not usually carried out before 30 days.
5. Conclusion
In summary, the variable associated with the success of cardioversion was mainly the short duration of AF (acute AF) and with the failure the use of digoxin and amiodarone. No association was found between the absence of restoration of SR and a higher 30-day ED revisit related to AF. In patients with AF, emergency physicians should determine whether patients are good candidates for ablation regardless of cardioversion outcomes. Therefore, each case must be independently evaluated and referred to an arrhythmia unit if necessary.
Availability of data and materials
The data presented in this study are available on reasonable request from the corresponding author.
Author contributions
IC—conceived the study, participated in its design and coordination and helped to draft the manuscript; JJ—participated in the design of the study and performed the statistical analysis; OY, MA, JAG, AM, PF, JS, AE, AZ, JMM—participated in data collection and revision of the manuscript. All authors read and approved the final manuscript.
Ethics approval and consent to participate
The present study was conducted according to the Declaration of Helsinki on Ethical Principles for Medical Research Involving Human Subjects, and patients provided informed consent to participate and to be contacted for follow-up. Patient data were anonymized for the purposes of this registry and patient confidentiality was maintained according to national standards. The study was approved by the Clinical Research Ethics Committee of Bellvitge University Hospital, Barcelona, Spain (reference number PR354/16).
Acknowledgment
We thank CERCA Programme/Generalitat de Catalunya for institutional support.
Members of the investigative team of the URGFAICS study: Oriol Yuguero, Xavier Ichart Tomas, Anna Moreno Pena (Hospital Arnau de Vilanova); Jorge-Alexis Guzman, Paloma Francés, Jesús Galvez Mora (Hospital Universitari Joan XXIII); Josep-Maria Mòdol, Anna Esquerrà, Adrià Steinherr, Neus Robert (Hospital Universitari Germans Trias i Pujol de Badalona); Javier Jacob, Irene Cabello, Alvaro Zarauza, Genis Camprubí (Hospital Universitari de Bellvitge); María Arranz, Julia Santos, Loreto Espuis Albas, Javier Del Castillo Nos, Àngel Sierra Moreno, Cristina Herranz Martínez (Hospital de Viladecans).
Funding
This research received no external funding.
Conflict of interest
The authors declare no conflict of interest.
