Spontaneous Cardioversion Research Articles

Dual vs Single Cardioversion of Atrial Fibrillation in Patients With Obesity

Atrial fibrillation and obesity are common, and both are increasing in prevalence. Obesity is associated with failure of cardioversion of atrial fibrillation using a standard single set of defibrillator pads, even at high output. To compare the efficacy and safety of dual direct-current cardioversion (DCCV) using 2 sets of pads, with each pair simultaneously delivering 200 J, with traditional single 200-J DCCV using 1 set of pads in patients with obesity and atrial fibrillation. This was a prospective, investigator-initiated, patient-blinded, randomized clinical trial spanning 3 years from August 2020 to 2023. As a multicenter trial, the setting included 3 sites in Louisiana. Eligibility criteria included body mass index (BMI) of 35 or higher (calculated as weight in kilograms divided by height in meters squared), age 18 years or older, and planned nonemergent electrical cardioversion for atrial fibrillation. Patients who met inclusion criteria were randomized 1:1. Exclusions occurred due to spontaneous cardioversion, instability, thrombus, or BMI below threshold. Dual DCCV vs single DCCV. Return to sinus rhythm, regardless of duration, immediately after the first cardioversion attempt of atrial fibrillation, adverse cardiovascular events, and chest discomfort after the procedure. Of 2079 sequential patients undergoing cardioversion, 276 met inclusion criteria and were approached for participation. Of these, 210 participants were randomized 1:1. After exclusions, 200 patients (median [IQR] age, 67.6 [60.1-72.4] years; 127 male [63.5%]) completed the study. The mean (SD) BMI was 41.2 (6.5). Cardioversion was successful more often with dual DCCV compared with single DCCV (97 of 99 patients [98%] vs 87 of 101 patients [86%]; P = .002). Dual cardioversion predicted success (odds ratio, 6.7; 95% CI, 3.3-13.6; P = .01). Patients in the single cardioversion cohort whose first attempt failed underwent dual cardioversion with all subsequent attempts (up to 3 total), all of which were successful: 12 of 14 after second cardioversion and 2 of 14 after third cardioversion. There was no difference in the rating of postprocedure chest discomfort (median in both groups = 0 of 10; P = .40). There were no cardiovascular complications. In patients with obesity (BMI ≥35) undergoing electrical cardioversion for atrial fibrillation, dual DCCV results in greater cardioversion success compared with single DCCV, without any increase in complications or patient discomfort. ClinicalTrials.gov Identifier: NCT04539158.

Factors predictive of spontaneous reversion to sinus rhythm: Findings from an integrated acute atrial fibrillation pathway

Recent evidence suggests that delayed cardioversion of uncomplicated acute AF is non-inferior to early cardioversion in the Emergency Department (ED), 1 Pluymaekers N.A.H.A. Dudink E.A.M.P. Luermans J.G.L.M. et al. Early or Delayed Cardioversion in Recent-Onset Atrial Fibrillation. N Engl J Med. 2019; 380: 1499-1508 Crossref PubMed Scopus (95) Google Scholar and most patients will revert spontaneously to sinus rhythm (SR) by a rate control strategy. 2 Abadie B.Q. Hansen B. Walker J. et al. Likelihood of Spontaneous Cardioversion of Atrial Fibrillation Using a Conservative Management Strategy Among Patients Presenting to the Emergency Department. Am J Cardiol. 2019; 124: 1534-1539 Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar We adopted a new inter-departmental acute AF clinical pathway 3 Al-Busaidi I.S. Clare G.C. Joyce L.R. et al. Presentation, Treatment and Long-Term Outcomes of a Multidisciplinary Acute Atrial Fibrillation Pathway: A 12-Month Follow-Up Study. Heart Lung Circ. 2022; 31: 216-223 Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar in 2015 which involves a ‘rate-and-wait’ strategy where patients are managed with rate control agents followed by a review in a ward-based clinic within 24-72 hours (97% attend within this time frame). Over two-thirds (71%) of pathway patients spontaneously reverted to SR by clinic review. 3 Al-Busaidi I.S. Clare G.C. Joyce L.R. et al. Presentation, Treatment and Long-Term Outcomes of a Multidisciplinary Acute Atrial Fibrillation Pathway: A 12-Month Follow-Up Study. Heart Lung Circ. 2022; 31: 216-223 Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar We examined predictors of spontaneous reversion to SR at AF clinic follow-up.

59 THE SHARK-FIN THAT EMERGES AND IMMERGES: A CASE REPORT OF TRANSIENT AND RIPETITIVE TRIANGULAR QRS-ST-T.

Abstract Introduction Shark fin sign, also known as triangular QRS-ST-T waveform (TW), is characterized by a giant R wave (amplitude ≥ 1 mV) resulting from the fusion of the QRS complex, the ST-segment and the T wave and showing triangular morphology. TW pattern is quite uncommon and reveals a life-threatening condition that needs aggressive management. Early recognition is important to prevent acute complications such as ventricular arrhythmias and cardiogenic shock. Case presentation A 45-years old black man with history of arterial hypertension presented with out-of-hospital cardiac arrest (OHCA) at his workplace. Extracorporeal cardiopulmonary resuscitation started immediately and return of spontaneous circulation occurred after 11 minutes and 2 DC shocks. Then he was transferred to our emergency department (ED). At arrival he was hemodynamically stable, ECG showed atrial fibrillation without any repolarization abnormalities and echocardiogram revealed left ventricular hypertrophy (IVS 12mm, PW 12mm) and normal biventricular function. Normal electrolytes and high-sensitivity troponin level of 14 (n.v. 0.01-19.8 ng/L) were found at the blood test. Sedation in the ED was needed due to psychomotor agitation. He was then transferred to the CCU where spontaneous cardioversion to sinus rhythm occurred, and no additional arrhythmias were noted at continuous ECG monitoring. After ten hours, while the patient was still under sedation, ECG monitoring revealed a progressive QRS-ST segment elevation in inferior leads up to a triangular QRS-ST-T giant waveform (“Shark fin sign”), without hemodynamic deterioration. After approximately 3 minutes the ECG showed a progressive and complete regression to a normal waveform. An emergent beside echocardiogram demonstrated inferior wall hypokinesia, but normal pump function. The episode repeated 5 more times in the following hour, waiting for cath lab personnel. Coronary angiography revealed a sub-occlusive mid RCA stenosis without any thrombotic lesion. Percutaneous coronary intervention (PCI) with the implantation of one drug eluting stent (DES) was performed. After the procedure the patient was hemodynamically and electrically stable. ECG did not show any other abnormality and no episodes of recurrent ST-elevation occurred. Sedation was suspended and no focal neurological deficits were noted. Discussion Shark fin sign is the expression of abrupt total deprivation of blood flow in large areas of myocardium that cause massive slowing of transmural electrical conduction. These electrical differences may be at the base of the triangular R waves and predispose to VF induction and cardiogenic shock. This sign is very rare, with an annual incidence of 0.7% in patients admitted for STEMI, and in most of the cases is described in the occlusion of the LAD. In our case we assisted to transient but repetitive inferior triangular ST-elevation with complete regression to normal ECG. The coronary angiogram showed non-obstructive lesion of the RCA. This phenomenon was probably the expression of RCA's plaque coronary vasospasm that caused the ECG shark fin sign and cardiac arrest. Conclusion Shark fin electrocardiographic waveform is an uncommon pattern of STEMI and may be the expression of thrombotic coronary occlusion as well as massive coronary vasospasm. This sign correlates with high risk of cardiogenic shock, electrical instability, and cardiac arrest, thus requiring prompt and aggressive management.

678 WIDE COMPLEX TACHYCARDIA IN A PATIENT TREATED WITH PERMANENT HIS BUNDLE PACING: A CASE REPORT

Abstract Introduction Differential diagnosis of wide complex tachycardias based only on ECG analysis remains a challenging exercise. But, when intracardiac tracings are available (i.e., pacemaker EGM), electrophysiologists may consider several tricks to make a correct diagnosis. Case Presentation A 73-years-old sporty male was admitted to our hospital for palpitations and dizziness. ECG monitoring revealed AF, typical atrial flutter and asystolic pauses following spontaneous cardioversion of atrial arrhythmias. We diagnosed sick sinus syndrome and implanted a dual-chamber pacemaker with an atrial lead in the right appendage and a stylet-directed active fixation lead in the His region, obtaining non-selective narrow paced QRS. The day after PM implantation, during a new episode of AF, two runs of regular wide-complex tachycardia (LBBB morphology, cycle length of 270 ms) occurred (Fig 1A, B). LBBB morphology, patient's history, and AF favored aberrancy, but couldn't exclude VT or preexcitation (by atrio-fascicular AP). Our diagnostic strategy consisted in adding atrial and His intracardiac electrograms registered by pacemaker to analysis of ECG traces. The device interrogation showed AV dissociation at the time of the wide complex tachyarrhythmia and a negative HV interval (Fig. 2A). These findings ruled out aberrant ventricular conduction and bundle branch reentrant tachycardia, because both these arrhythmias are characterized by HV ≥ HV in sinus rhythm. We performed incremental atrial pacing maneuver, during SR, obtaining decremental AH conduction with constant HV interval (60 ms), excluding atrio-fascicular, nodo-fascicular and nodo-ventricular AP. His bundle activity was identified just after the ventricular activation, producing a relatively short VH interval, suggesting the presence of a retrograde activation of the His bundle, therefore it was possible to hypothesize that the site of origin of the ventricular arrhythmia was within/or very close to RBB (Fig 2B, C). Just in few beats His bundle deflection was missing, probably because of recovery of functional LBBB (Fig 2D). Discussion Our final diagnosis was RBB VT. Patient was treated with Verapamil 80 mg t.i.d., with no further recurrence. This case highlights the diagnostic value of device interrogation in patients with permanent His bundle pacing, for the evaluation of wide complex tachycardias.

Abstract 13506: Three-Dimensional Transoesophageal Echocardiography Characterization of Left Atrial Appendage Dimensions in Patients With Spontaneous Cardioversion of Atrial Fibrillation

Introduction: Few studies have described the clinical profile and natural history of patients with spontaneous cardioversion (SpCV) in atrial fibrillation (AF). Hypothesis: We hypothesized that patients with SpCV have a distinct morphological pattern in AF. Methods: We prospectively evaluated 262 patients hospitalized for AF using two-dimensional (2D) transthoracic (TTE) and three-dimensional (3D) transoesophageal echocardiography (TEE). 3D parameters were off-line analysed using Tomtec software (4D Cardio-View, Philips). Patients were divided into two groups according to the cardiac rhythm within 24 hours after admission: spontaneous cardioversion (SpCV group, 59 patients) and non-spontaneous cardioversion (noSpCV group, 203 patients). Results: Mean age of the population was 66±12 years and 166 (63%) patients were male. SpCV group had in comparison with noSpCV group lower CRP levels (respectively 3.3(3-5.5) versus 4(3-10) mg/L, p=0.0394), lower BNP levels (151(67-200) versus 269(129-424) pg/mL, p<0.001) and lower HBA1c levels (5.5(5.3-5.7) versus 5.9(5.6-6.3) %, p<0.0001). Using 2D TTE, SpCV group had in comparison with noSpCV group lower indexed left atrial end-systolic volume, lower indexed right atrial end-systolic volume, lower E velocity, and higher left ventricle ejection fraction (Table 1). Based on 2D and 3D TEE, SpCv group had in comparison with noSpCV group higher LAA emptying flow velocity and higher LAA filling flow velocity, lower 3D end-systolic and end-diastolic LAA volumes (both non-indexed and indexed) and lower 3D LAA ostium in comparison with noSpCV group (Table 1). Conclusions: Although SpCv of AF is a frequent situation incompletely studied, clinical and echocardiographic characteristics could be described. Further investigations are needed to determine the impact of such abnormalities on the prognosis in the SpCV group.

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 the efficacy between Del Nido cardioplegia and HTK cardioplegia in Stanford type A aortic dissection patients undergoing open-heart surgery.

Acute Stanford type A aortic dissection is an extremely dangerous and life-threatening cardiovascular disease, usually treated with extracorporeal circulation heart surgery. Histidine-tryptophan-ketoglutarate (HTK) cardioplegia is a protective intracellular myocardial fluid that has been used extensively in different types of extracorporeal circulation surgeries. Del Nido cardioplegia is an extracellular myocardial protection fluid, which was first used in pediatric heart surgery and has been gradually used in a variety of pediatric and adult heart procedures. This study aims to compare the myocardial protection effect between Del Nido and HTK in patients undergoing extracorporeal circulation heart surgery for acute Stanford type A dissection and its impact on patients' prognosis by analyzing selected parameters and clinical manifestations at different time points. Clinical data were collected from 431 patients with acute Stanford type A dissection who were diagnosed and underwent surgery between January 1, 2018 and December 31, 2020 at Xiangya Hospital, Central South University. After excluding some of the data based on exclusion criteria, patients were divided into a HTK group and a Del Nido (DN) group based on type of intraoperative cardioplegia. Propensity score-matching was performed subsequently using the the R statistical software to determine the DN group ( n =40) and HTK group ( n =41). The matching factors were age, sex, hypertension, cardiopulmonary bypass time, and aortic occlusion time. Perioperative data, postoperative complications, blood gas data, and myocardial injury data were collected from the patients, and SPSS 26.0 was used to analyze the data of each group. The DN group had a higher rate of spontaneous cardioversion (41.5% vs 15.0%, P =0.005) and a lower postoperative hospital stay [10.0(8.0,14.0) d vs 13.0(11.0,19.0) d, P <0.05] compared to the HTK group. In terms of changes in blood gas analysis, immediate sodium and potassium concentrations were significantly higher in the DN group than that in the HTK group (both P <0.05). There was no significant difference in myocardial injury indexes between the two groups at different time points (all P >0.05). In terms of postoperative complications, the cardiac complications in DN group were much lower than those in the HTK Group (0 vs 12.5%, P =0.026). Del Nido cardioplegia has similar myocardial protective effects as HTK cardioplegia used in Stanford type A aortic dissection, with a higher rate of cardiac recurrence and fewer cardiac complications. Del Nido cardioplegia should play an important role in future application for acute Stanford type A aortic dissection, but our findings need to be further validated in a large sample of prospective clinical studies.

How to Optimize Cardioversion of Atrial Fibrillation.

Cardioversion (CV) is an essential component of rhythm control strategy in the treatment of atrial fibrillation (AF). Timing of CV is an important manageable factor in optimizing the safety and efficacy of CV. Based on observational studies, the success rate of CV seems to be best (≈95%) at 12–48 h after the onset of arrhythmic symptoms compared with a lower success rate of ≈85% in later elective CV. Early AF recurrences are also less common after acute CV compared with later elective CV. CV causes a temporary increase in the risk of thromboembolic complications. Effective anticoagulation reduces this risk, especially during the first 2 weeks after successful CV. However, even during therapeutic anticoagulation, each elective CV increases the risk of stroke 4-fold (0.4% vs. 0.1%) during the first month after the procedure, compared with acute (<48 h) CV or avoiding CV. Spontaneous CVs are common during the early hours of AF. The short wait-and-see approach, up to 24–48 h, is a reasonable option for otherwise healthy but mildly symptomatic patients who are using therapeutic anticoagulation, since they are most likely to have spontaneous rhythm conversion and have no need for active CV. The probability of early treatment failure and antiarrhythmic treatment options should be evaluated before proceeding to CV to avoid the risks of futile CVs.

On the essence of cardiopulmonary resuscitation

This article discusses that the essence of cardiopulmonary resuscitation (CPR) is energy transfer. The concept of occult cardiac arrest is proposed, and cardioversion after cardiac arrest is divided into spontaneous cardioversion and CPR according to the principle of energy transfer: the internal energy transmission of the body makes the cardioversion that is known as spontaneous cardioversion, and energy is mainly transfers from the outside leads to cardioversion, that is, CPR. The concept of domain energy in CPR is proposed, and it is argued that only energy transfer beyond the domain energy can lead to cardioversion in both spontaneous cardioversion and CPR. The principle of energy transfer is used to explain the common clinical electrocardiographic phenomena: dysrhythmia can occur when the energy required for the cardiac functions is insufficient, it is a manifestation of self-protection of the heart and the body, and the mechanism is further argued. It is demonstrated that serious cardiac events, such as ventricular fibrillation and cardiac arrest, are special types of cardiac self-protection. The mechanisms, general rules, and energy properties of modern CPR energy transfer are described, and the influence and interaction of energy transfer principle on the three states of time, space, and energy transfer during CPR are assessed, which will be significant for future research on CPR.

PO-674-04 ANTICOAGULATION MANAGEMENT AND RISK OF THROMBOEMBOLISM IN HEALTHY YOUTH WITH ATRIAL FIBRILLATION: DATA FROM A MULTI-INSTITUTIONAL PACES COLLABORATIVE REGISTRY

Stroke is a well-defined complication of atrial fibrillation (AF) in adults. However, the risk of thromboembolism and need for anticoagulation therapy in children and young adults with AF are unknown. To describe the current anticoagulation practice and assess the risk of thrombosis in children and young adults with AF across 13 pediatric heart centers. Data was obtained from the multi-institutional PACES collaborative registry on atrial fibrillation. Patients ≤ 21 years of age with documented AF of an unknown cause from January 2004 to December 2018 were included. We included patients with AF with no structural heart disease, cardiomyopathy, ventricular pre-excitation, history of open heart surgery, hypertension, or thyroid disease. Of 241 subjects, 76 were prescribed oral anticoagulation at diagnosis and an additional 15 at time of AF recurrence. Aspirin was prescribed in 66 (73%) patients, warfarin in 14 (15%), novel oral anticoagulant in 7 (8%), combined therapy in 3 (3%), and unknown in 1 (1%). In a multivariable model, patients were less likely to be anticoagulated at a freestanding children’s hospital (OR 0.44, 95%CI [0.23-0.78], p=0.005) or if they had spontaneous cardioversion (OR 0.53, 95%CI [0.29-0.96], p=0.037), and more likely if prescribed an antiarrhythmic at time of initial diagnosis (OR 1.82, 95%CI [1.01-3.3], p=0.047). There was a trend towards anticoagulation in patients presenting with asymptomatic AF (OR 0.45, 95%CI [0.19-1.03], p=0.06]). Age at diagnosis, gender, and BMI were not associated with anticoagulation status. One patient (1/241, 0.4%) was found to have left atrial thrombus confirmed by transesophageal echocardiogram at time of presentation. This patient was treated with warfarin for 3 months and repeat echocardiogram showed thrombus resolution. No patient developed thromboembolic phenomenon over a mean follow up of 2.1 ± 2.6 years. Our study is the first to demonstrate that there is large practice variation in anticoagulation management with patients treated at a free-standing children’s hospital being less likely to be anticoagulated. AF associated thrombosis is rare in children and young adults.

FAILURE TO CONSIDER FUTURE ATRIAL FIBRILLATION RATE CONTROL NEEDS AFTER PRESENTATION TO THE EMERGENCY DEPARTMENT WITH RAPID RATE

Atrial fibrillation (AF) usually presents to the emergency room (ED) with a rapid ventricular rate, which commonly, but not always, is symptomatic. Rate control is usually easily managed with diltiazem (DTZ) and beta blockers (BBs), typically metoprolol (MTP). Sinus rhythm is frequently restored within 48 hours by means of spontaneous conversion, electrical cardioversion, or medications. However, AF recurs within one year in 60-80% of these subjects. There are little data describing doses of DTZ and MTP used for AF rate control at discharge. A retrospective study of 576 patients presenting with acute AF were evaluated for admission and discharge rate control medications (RCMs). For the 319 (68%) patients with a ventricular rate ≥110bpm the admission and discharge dose of MTP was 61mg and 63mg and DTZ was 195mg and 204mg, respectively. Those who remained in AF had a modest increase in the two medications compared to the patients who converted to sinus rhythm. Current guidelines recommend DTZ up to 300 to 400mg and MTP up to 300mg for rate control for select patients. Concerns about high doses of MTP are mitigated by the MERIT-HF Trial demonstrating improved mortality and symptoms with doses of MTP up to 200mg demonstrating the safety and efficacy of MTP in high risk patients. Lack of follow-up of future AF recurrences is a limitation of the study. For those patients with acute AF and a heart rate (HR) &gt;110bpm, a minimal increase in RCMs for those in AF at discharge was noted.

Presentation, Treatment and Long-Term Outcomes of a Multidisciplinary Acute Atrial Fibrillation Pathway: A 12-Month Follow-Up Study

Atrial fibrillation/flutter (AF/AFL) is associated with high rates of emergency department (ED) visits and acute hospitalisation. A recently established multidisciplinary acute AF treatment pathway seeks to avoid hospital admissions by early discharge of haemodynamically stable, low risk patients from the ED with next-working-day return to a ward-based AF clinic for further assessment. We conducted a preliminary analysis of the clinical outcomes of this pathway. We retrospectively reviewed clinical records of all patients assessed at the AF clinic at Christchurch Hospital, New Zealand, over a 12-month period. Data related to presentation, patient characteristics, treatment, and 12-month outcomes were analysed. A total of 143 patients (median age 65, interquartile range: 57-74 years, 59% male, 87% European) were assessed. Of these, 87 (60.8%) presented with their first episode of AF/AFL. Spontaneous cardioversion occurred in 41% at ED discharge, and this increased to 73% at AF clinic review. Electrical cardioversion was subsequently performed in 16 patients (11.2%), and 16 (11.2%) ultimately required hospital admission (eight to facilitate electrical cardioversion). At a median of 1 day, 83.9% were discharged from the AF clinic in sinus rhythm. During 12-month follow-up, there were 25 AF-related hospitalisations (20 patients, 14%) and one patient underwent electrical cardioversion; additionally, one patient had had a stroke and eight had bleeding complications giving a combined outcome rate of 6.3%. Utilising a rate-control strategy with ED discharge and early return to a dedicated AF clinic can safely prevent the majority of hospitalisations, avert unnecessary procedures, and facilitate longitudinal care.

Targeting Bachmann's bundle in hybrid ablation for long-standing persistent atrial fibrillation: a proof of concept study.

Catheter-based or surgical procedures in patients with long-standing persistent atrial fibrillation (LSPAF) remain a challenge. As a result, different approaches including hybrid (surgical and endocardial) ablation have been developed. Bachmann's bundle (BB) is a mainly epicardial structure capable of sustaining arrhythmic reentry that could be involved in the development and perpetuation of atrial fibrillation. We investigated the efficacy and safety of an adjunctive BB ablation in LSPAF patients undergoing hybrid ablation. In a two-arm non-randomized study, consecutive LSPAF patients undergoing epicardial isolation of pulmonary veins with left atrial posterior wall (box lesion) with (n = 30, BB group) and without additional BB ablation (n = 30, CONV group) were enrolled in the study. All patients underwent an endocardial procedure within 6 weeks post-surgery to assess for potential lesion gaps and additional atrial substrate modification. The primary endpoint was freedom from AF through 12 months of follow-up. The two-staged hybrid ablation was successfully completed in all patients. One-year freedom from atrial arrhythmias recurrence rates was 96.6% in the BB group vs 76.6% in the CONV group (p = 0.025). At procedure completion, 30 (100%) and 17 (56%) patients had a spontaneous cardioversion in BB and CONV group, respectively (p < 0.001). No significant differences in quality of life or complication rates were observed. This initial experience shows, for the first time, that adjunctive BB ablation in the setting of hybrid ablation for LSPAF is a feasible and effective approach in increasing maintenance of sinus rhythm without increasing complication rates.

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

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. 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. 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 1day (interquartile range, 1-2days). 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 -0.67sec-1, as derived from receiver operator curve analysis (P<.001). 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.

Biatrial remodelling in atrial fibrillation: A three-dimensional and strain echocardiography insight

Atrial remodelling has been poorly investigated in atrial fibrillation (AF), and few studies have focused on biatrial remodelling. To evaluate right atrial (RA) and left atrial (LA) remodelling in AF using global atrial reservoir strain and three-dimensional (3D) atrial volumes, according to rhythm outcome at mid-term follow-up. Two-dimensional and 3D transthoracic echocardiography (TTE) were performed within 24hours after admission (M0) and at 6-month follow-up (M6) in patients admitted for AF. RA and LA variables were assessed: body surface area-indexed maximum 3D volume (Max 3D RA Voli, Max 3D LA Voli) and minimum 3D volume (Min 3D RA Voli, Min 3D LA Voli); atrial emptying fraction (3D RAEF, 3D LAEF); atrial expansion index (3D RAEI, 3D LAEI); and global RA and LA reservoir strain. Forty-eight consecutive patients were included prospectively. Three groups were identified depending on rhythm at M0 and M6: AF at M0 and sinus rhythm (SR) at M6 (AF-SR) in 25 (52.1%) patients; AF at M0 and AF at M6 (AF-AF) in 13 (27.1%) patients; and SR at M0 (spontaneous cardioversion before first TTE) and SR at M6 (SR-SR) in 10 (20.8%) patients. Between M0 and M6 in the AF-SR group, we found: significant decreases in Max 3D RA Voli (P=0.020), Min 3D RA Voli (P=0.0008), Max 3D LA Voli (P=0.001) and Min 3D LA Voli (P=0.0021); significant increases in 3D RAEF (P=0.037) and 3D RAEI (P=0.034); no significant differences in 3D LAEF and 3D LAEI; and significant increases in global RA and LA reservoir strain (both P<0.0001). There was no significant difference with regard to these variables in the AF-AF and SR-SR groups. 3D volume and strain analyses were useful in the evaluation of RA and LA reverse remodelling in successfully cardioverted patients with AF.

Likelihood of Spontaneous Cardioversion of Atrial Fibrillation Using a Conservative Management Strategy Among Patients Presenting to the Emergency Department

Numerous emergency department (ED) atrial fibrillation (AF) protocols have been developed to reduce hospitalizations, focusing on the use of cardioversion in the ED. An alternative strategy of rate control with early specialty follow-up may be more widely applicable. The likelihood of spontaneous cardioversion with such a protocol is unknown. Between 2015 and 2018, 157 patients who presented to the ED with a primary diagnosis of AF and were hemodynamically stable and with low to moderate symptom severity were discharged with early follow-up at an AF specialty clinic. Rhythm at short-term (within 72 hours), within 30-day follow-up, and need for electrical cardioversion was tabulated. Various demographic and co-morbidity variables were assessed to determine their association with likelihood of spontaneous cardioversion. At an average of 2.3 days, 63% and within 30 days, 83% had spontaneous cardioversion. By 90 days, only 6.3% required electrical cardioversion. Diabetes (38% vs 69%, p <0.01), coronary artery disease (39% vs 66%, p = 0.02), reduced ejection fraction (40% vs 72%, p <0.01), dilated right atrium (43% vs 73%, p <0.01) and moderate-to-severely dilated left atrium (38% vs 78%, p <0.01) predicted those who were less likely to convert to sinus rhythm. Most patients who present to the ED with AF will spontaneously convert to sinus rhythm by short-term (2 to 3 days) follow-up with a rate control strategy. In conclusion, aggressive use of electrical cardioversion in the ED may be unnecessary in hemodynamically stable patients without severe symptoms.

Initial bi atrial three-dimensional echocardiographic evaluation in non-valvular atrial fibrillation according to rhythm outcome at six month follow-up

Two-dimensional left atrial (LA) size is an independent echocardiographic predictor of atrial fibrillation (AF) occurrence and recurrence. Our study aimed to evaluate LA and right atrial (RA) three-dimensional (3D) volumes at admission (M0) in patients with AF to define atrial remodeling according to rhythm outcome at 6 month follow-up (M6). 3D RA and LA parameters were assessed at M0 in patients admitted for AF: body surface area-indexed maximum 3D volume (Max 3D RA Voli, Max 3D LA Voli) and indexed minimum volume (Min 3D RA Voli, Min 3D LA Voli); atrial emptying fraction (3D RAEF, 3D LAEF) and atrial expansion index (3D RAEI, 3D LAEI). Forty-eight consecutive patients hospitalized for AF were prospectively included. Two groups were individualized according to rhythm outcome: successful cardio version (SuccCV) in 35(72.9%) patients including either spontaneous ( n = 10) or electrical cardioversion ( n = 25) (AF at M0 and sinus rhythm (SR) at M6); failure or contra indication to cardioversion (FailCV) in 13(27.1%) patients (AF at M0 and AF at M6). 3D echocardiographic evaluation from 41 patients at M0 found: – significantly upper Min 3D RA Voli, Min 3D LA Voli in group FailCV in comparison with SuccCV; – significantly lower 3D RAEF, 3D RAEI, 3D LAEF, 3D LAEI in group FailCV in comparison with SuccCV; – no significant differences regarding Max 3D RA Voli, Max 3D LA Voli between groups FailCV and SuccCV ( Table 1 ). 3D atrial echocardiographic parameters could be useful to predict initial atrial remodelling in patients admitted for AF.

The Lazarus phenomenon: spontaneous cardioversion after termination of resuscitation in a Scottish hospital

A 66-year-old man suffered a ventricular fibrillation cardiac arrest after an episode of chest pain. Despite advanced life support, his condition deteriorated; the situation was considered irrecoverable and resuscitation was...

Atrial Fibrillation in a Structurally Normal Heart during Pregnancy: A Review of Cases From a Registry and From the Literature.

Atrial fibrillation (AF) in a structurally normal heart is rare during pregnancy. We wished to use our experience to expand the literature on the causes and management of this condition. All members of Groupe d'Étude en Médecine Obstétricale du Québec (GÉMOQ) were invited to record cases of AF in a structurally normal heart during pregnancy to the group's Registry. We searched Medline, PubMed, and Google Scholar (1946 to 15 April 2016) for relevant articles using the key words "atrial fibrillation" and "pregnancy." Sixteen pregnancies with AF in 12 women were recorded in the Registry, and 19 pregnancies with AF in 18 women were retrieved from the literature. The majority (94% in the Registry and 89% in the literature) presented with paroxysmal AF. We found differences between characteristics recorded in the literature and in the Registry; these were the presence of classic triggers for AF (37% in the literature vs. 0% in the Registry), the rate of recurrence of AF in the same pregnancy (5% vs. 31%) or in subsequent pregnancies (1 vs. 4), the rate of spontaneous cardioversion (50% vs. 81%), the use of acetylsalicylic acid and/or low molecular weight heparin as stroke preventive therapy (35% vs. 71%), and the rate of AF influencing the decision to deliver (21% vs. 6%). One woman in the Registry with persistent AF had a left atrial appendage thrombus. The GÉMOQ's Registry added 12 cases (16 pregnancies) to the existing literature. AF during pregnancy is an arrhythmia that ismainly unprovoked, paroxysmal, and stable, with spontaneous cardioversion occurring usually within 24 hours. It is associated with good pregnancy outcomes.

Abstract 13948: High Intraprocedural Atrial Fibrillation Termination Rate by Large Area Rotor Ablation Combined With Pulmonary Vein Isolation

Introduction: There remains contradictory data about the optimal ablation technique and the type of termination of atrial fibrillation (AF) ablation particularly in patient (pt) with persistent AF. The aim of this study was to determine the type of the termination of persistent AF during combined conventional and rotor ablation. Method: This is a single-center, prospective, observational study enrolled thirty-eight pts (24/63% male, mean age 63 years) with AF (mean left atrial size: 46,2 ± 7 mm), who underwent focal impulse and rotor modulation (FIRM) mapping and large area ablation around the core of the identified rotor(s), followed by conventional pulmonary vein isolation(PVI) using contact force catheter aiming 10-20 gr depending on the location. Two distinctive types of the AF termination were defined: sub-acute termination related to rotor elimination, furthermore acute termination due to PVI. Electric cardioversion (ECV) was executed only in the absence of spontaneous conversion to sinus rhythm (SR). Result: In 10(26%) pts acute AF termination after PVI was observed. In further 12 (31%) pts sub-acute termination of the AF could be observed after the identified rotor ablation. The combined technique of conventional and rotor ablation of pts with persistent AF resulted in 57,8% of termination rate. Spontaneous cardioversion could not be reached in 16 (42%) pts however 15 out of them were converted to SR by ECV. Procedural complication occurred in 3 pts presenting with groin hematoma, in one patient left atrial appendage (LAA) thrombus was revealed by transoesophageal echocardiography performed right after the ablation for guiding the planned LAA closure. Conclusion: Large area rotor ablation drag technique combined with contact force sensing technique results in a high termination rate of persistent AF. More studies are warranted to define the clinical significance and long term success rate of rotor ablation in pts with persistent atrial fibrillation.