Elective Direct Current Cardioversion Research Articles

Low-Amplitude Electrocardiogram in a Patient with Atrial Fibrillation, Direct-Current Electrical Cardioversion, and Takotsubo Cardiomyopathy

To the Editor:I read with pleasure the report by Siegfried and colleagues1 about a woman with atrial fibrillation who had an episode of takotsubo cardiomyopathy (TC) immediately after undergoing direct-current electrical cardioversion of her atrial fibrillation. In their discussion, the authors provide a convincing and comprehensive analysis of the incident.I was impressed with the low voltage in the admission electrocardiogram (ECG) and in the one after cardioversion. Transient low-voltage ECG has been described recently in association with TC2; accordingly, I would greatly appreciate information on the patient's ECGs before hospital admission and at follow-up. If these ECGs did not reveal low voltage, then TC was present before the hospital admission as a result of atrial fibrillation, even though the authors did not observe the consequences of TC in the echocardiogram and the release of cardiac troponin I before cardioversion.doi: http://dx.doi.org/10.14503/THIJ-14-4486I thank Dr. Madias for his insightful response to our report.1 In regard to the patient's electrocardiographic (ECG) voltage, review of the available data reveals low voltage in the limb and precordial leads 2 years before her presentation (Fig. 1), which was the most recent prior ECG. An ECG obtained at the time of follow-up, 2 weeks after the patient's discharge from the hospital, showed similar findings (Fig. 2). Although there appears to be a general association between low voltage and takotsubo cardiomyopathy,2 in this case the low voltage appears to have been the patient's baseline status, most likely due to body habitus.

Warfarin vs Dabigatran for elective direct current cardioversion (DCCV)

Background: In clinical practice, achieving 4 weeks of therapeutic anticoagulation with warfarin is challenging and hinders timely DCCV. Dabigatran is a safe and effective alternative. We evaluated the difference in time to DCCV and success rate between those on dabigatran compared to warfarin.Method: Patients who had DCCV between 12/1/2011 and 31/12/2013 were prospectively collected. Patient demographics and electronic clinical documentations were retrospectively reviewed.Results: Total of 168 DCCV were performed on 153 patients. Mean age was 61 years and mean BMI was 32kg/m2 with male predominance (80.4%). 87.6% of patients were referred from Cardiology and 12.4% from General Medicine. 45.2% (n = 76) were on dabigatran.The median days to DCCV with dabigatran was 63 days (IQR = 44 – 100 days) and 86 days for warfarin (IQR = 56 – 121days), p < 0.05. The overall immediate success rate of DCCV was 80.4%. 94.1% of atrial flutter (AFL) had successful cardioversion and 76.5% for atrial fibrillation (AF).At median follow-up of 108 days, 25.5% remained in sinus rhythm (SR). Those with AFL, 50% (n = 17) remained in SR at median follow up of 69 days while 18.5% of AF remained in SR at median follow up of 130.5 days.There was no difference in the immediate success of DCCV between dabigatran and warfarin groups (80.3% vs 80.4%, p = 0.89). AF accounted for 80.3% and 77.2% respectively.Conclusion: The median time to outpatient DCCV was 23 days shorter with dabigatran compared warfarin therapy. There was no difference in success rate between the 2 anticoagulation groups. Background: In clinical practice, achieving 4 weeks of therapeutic anticoagulation with warfarin is challenging and hinders timely DCCV. Dabigatran is a safe and effective alternative. We evaluated the difference in time to DCCV and success rate between those on dabigatran compared to warfarin. Method: Patients who had DCCV between 12/1/2011 and 31/12/2013 were prospectively collected. Patient demographics and electronic clinical documentations were retrospectively reviewed. Results: Total of 168 DCCV were performed on 153 patients. Mean age was 61 years and mean BMI was 32kg/m2 with male predominance (80.4%). 87.6% of patients were referred from Cardiology and 12.4% from General Medicine. 45.2% (n = 76) were on dabigatran. The median days to DCCV with dabigatran was 63 days (IQR = 44 – 100 days) and 86 days for warfarin (IQR = 56 – 121days), p < 0.05. The overall immediate success rate of DCCV was 80.4%. 94.1% of atrial flutter (AFL) had successful cardioversion and 76.5% for atrial fibrillation (AF). At median follow-up of 108 days, 25.5% remained in sinus rhythm (SR). Those with AFL, 50% (n = 17) remained in SR at median follow up of 69 days while 18.5% of AF remained in SR at median follow up of 130.5 days. There was no difference in the immediate success of DCCV between dabigatran and warfarin groups (80.3% vs 80.4%, p = 0.89). AF accounted for 80.3% and 77.2% respectively. Conclusion: The median time to outpatient DCCV was 23 days shorter with dabigatran compared warfarin therapy. There was no difference in success rate between the 2 anticoagulation groups. CSANZ NZ AbstractsHeart, Lung and CirculationVol. 23Preview Full-Text PDF

Electrical Cardioversion in Pregnancy: How Do We Do?

1 , Vedat Davutoglu 1 , Ibrahim Sari 1 ABSTRACT Introduction: Complaints of palpitations during pregnancy are common and often follow a benign clinical course. Tachycardia requiring intervention occurs in about 0.2-0.3% of these patients. Case Report: A pregnant 27-year-old with a history of rheumatic mitral valve disease was admitted with complaints of palpita- tions. Patient developed new onset atrial fibrillation and, with the implemented successful direct current electrical cardioversion, returned to sinus rhythm. Conclusion: Electrical cardioversion, applied with attention to placement with low-joule and foetuses kept as far as possible away from the pad, is considered to be safe in pregnant women with arrhythmia requiring cardioversion.

Takotsubo Cardiomyopathy as a Sequela of Elective Direct-Current Cardioversion for Atrial Fibrillation

In takotsubo cardiomyopathy, the clinical appearance is that of an acute myocardial infarction in the absence of obstructive coronary artery disease, with apical ballooning of the left ventricle. The condition is usually precipitated by a stressful physical or psychological experience. The mechanism is unknown but is thought to be related to catecholamine excess. We present the case of a 67-year-old woman who experienced cardiogenic shock caused by takotsubo cardiomyopathy, immediately after undergoing elective direct-current cardio-version for atrial fibrillation. After a course complicated by left ventricular failure, cardiogenic shock, and ventricular tachycardia, she made a complete clinical and echocardiographic recovery. In addition to this case, we discuss the possible direct effect of cardioversion in takotsubo cardiomyopathy.

Safety of Short-Term Use of Dabigatran or Rivaroxaban for Direct-Current Cardioversion in Patients With Atrial Fibrillation and Atrial Flutter

Direct-current cardioversion (DCCV) for persistent atrial fibrillation or atrial flutter (AF) carries a risk of thromboembolic events (TEs). Therapeutic anticoagulation with warfarin is recommended for 3 to 4 weeks before and 4 weeks after DCCV to reduce TE; however, the safety of short-term anticoagulation with the novel oral anticoagulants (dabigatran and rivaroxaban) before DCCV has not been assessed. A retrospective cohort study was performed on all patients undergoing elective DCCV for AF at Northwestern Memorial Hospital from June 1, 2012 to September 30, 2013. Inclusion criteria included patients taking any of the novel oral anticoagulants for 21 to 60 days before DCCV and successful DCCV to sinus rhythm. Patients were monitored for a minimum of 60 days after DCCV to evaluate for TEs including stroke, transient ischemic attack, systemic emboli, and death. In total, 53 patients (47 men, 89%; age 65±10 years, median 66) were evaluated. Agents used were dabigatran (30 patients, 57%) and rivaroxaban (23 patients, 43%) for an average of 38±9 days. The mean CHADS2 score was 1.2±1.1 (score=0, 26%; 1, 43%; 2, 17%; and >3, 13%). Eleven patients (21%) underwent a transesophageal echocardiography before their DCCV; all showed no thrombus. No patients were found to have episodes of TE within 60 days of DCCV. No patients were found to have major bleeding events. In conclusion, the use of short-term dabigatran or rivaroxaban therapy for DCCV of AF appears safe.

Low-Amplitude Electrocardiogram in a Patient with Atrial Fibrillation, Direct-Current Electrical Cardioversion, and Takotsubo Cardiomyopathy

Low-Amplitude Electrocardiogram in a Patient with Atrial Fibrillation, Direct-Current Electrical Cardioversion, and Takotsubo Cardiomyopathy

Dabigatran improves the efficiency of an elective direct current cardioversion service

Dabigatran improves the efficiency of an elective direct current cardioversion service

Total Atrial Conduction Time Assessed by Tissue Doppler Imaging (PA‐TDI Interval) to Predict Early Recurrence of Persistent Atrial Fibrillation After Successful Electrical Cardioversion

The aim of this study was to investigate whether total atrial conduction time (TACT) assessed via tissue Doppler imaging (PA-TDI interval) can identify patients with early recurrent atrial fibrillation (ERAF) after successful direct-current electrical cardioversion (CV) of persistent atrial fibrillation (persPAF). A total of 54 patients without antiarrhythmic drug medication (mean ± SD: 66 ± 10.4 years; 33% women) with persPAF and successful CV were enrolled between May 2012 and May 2013. TACT was measured 6 hours after successful CV in the left atrium by tissue Doppler imaging (PA-TDI interval). ERAF was determined via Holter-electrocardiogram over a period of 7 days after CV. Receiver opearting characteristic analysis was used to determine an optimal cutoff value of PA-TDI interval for prognosis of ERAF. Based on this result, recurrence-free survival was assessed with Mantel-Haenszel's log-rank test. ERAF occurred in 23 patients (43%). PA-TDI interval was longer in patients with ERAF compared to those who maintained sinus rhythm (mean ± SD: 163.5 ± 11.1 vs 132.3 ± 11.2 milliseconds; P < 0.00001). At the cutoff value of 152 milliseconds, PA-TDI interval sensitivity and specificity related to ERAF were 87% and 100%, respectively. Measuring PA-TDI interval may help to predict ERAF after successful CV in patients with persAF.

Common genetic polymorphism at 4q25 locus predicts atrial fibrillation recurrence after successful cardioversion.

Genome-wide association studies have identified numerous common polymorphisms associated with atrial fibrillation (AF). The 3 loci most strongly associated with AF occur at chromosome 4q25 (near PITX2), 16q22 (in ZFHX3), and 1q21 (in KCNN3). To evaluate whether timing of AF recurrence after direct current cardioversion (DCCV) is modulated by common AF susceptibility alleles. A total of 208 patients (age 65 ± 11 years; 77% men) with persistent AF underwent successful DCCV and were prospectively evaluated at 3, 6, and 12 months for AF recurrence. Four single nucleotide polymorphisms--rs2200733 and rs10033464 at 4q25, rs7193343 in ZFHX3, and rs13376333 in KCNN3--were genotyped. The final study cohort consisted of 184 patients. In 162 (88%) patients, sinus rhythm was restored with DCCV, of which 108 (67%) had AF recurrence at a median of 60 (interquartile range 29-176) days. In multivariable analysis, the presence of any common single nucleotide polymorphism (rs2200733, rs10033464) at the 4q25 locus was an independent predictor of AF recurrence (hazard ratio 2.1; 95% confidence interval 1.21-3.30; P = .008). Furthermore, rs2200733 exhibited a graded allelic dose response for early AF recurrence (homozygous variants: 7 [interquartile range 4-56] days; heterozygous variants: 54 [28-135] days; and wild type: 64 [29-180] days; P = .03). To our knowledge, this is the first study to evaluate whether genomic markers can predict timing of AF recurrence in patients undergoing elective DCCV. Our findings show that a common polymorphism on chromosome 4q25 (rs2200733) is an independent predictor of AF recurrence after DCCV and point to a potential role of stratification by genotype.

Prediction of Long‐Term Outcomes of Catheter Ablation of Persistent Atrial Fibrillation by Parameters of Preablation DC Cardioversion

It has been demonstrated that atrial fibrillation (AF) frequently recurred after cardioversion (CV) using direct current (DC) or radiofrequency catheter ablation (RFCA) in patients with persistent (PeAF) or longstanding persistent AF (LPAF). We hypothesized that the atrial substrate impeding successful CV would also produce difficulty in catheter ablation, and therefore, the outcomes of RFCA for PeAF and LPAF could be predicted by the parameters determined at the time of DC CV. From 2006 to 2009, 94 patients with PeAF and LPAF who had undergone elective DC CV before RFCA were studied. The parameters associated with DC CV, including number of shocks, cumulative energy adjusted, highest energy adjusted, with or without intravenous amiodarone use, and other clinical parameters were assessed. Thirty-two out of the 94 patients (34%) experienced AF recurrence during the follow-up of 19.8 ± 12.3 months after RFCA. The average time to recurrence of AF after RFCA was 9.2 ± 3.2 months. Of the 62 patients, 29 patients (31%) remained sinus rhythm (SR) without antiarrhythmic drug (AAD). The patients who maintained SR had smaller body mass index (BMI) (P = 0.048), shorter duration of AF (P = 0.012), and lower prevalence of diabetes mellitus (P = 0.023) compared with patients in whom AF recurred. Total number of shocks, total energy, and highest shock energy during CV were lower (P < 0.001, P = 0.002, P = 0.048, respectively) in patients with SR during the follow-up. The outcome in patients who used amiodarone IV prior to CV, however, was not different from that in those who did not use amiodarone IV. DC energy parameters for successful CV before RFCA were useful to predict the long-term outcome after RFCA in patients with PeAF and LPAF. The presence of the atrial substrate making DC CV difficult might reflect atrial substrate that subsequently related to the recurrence of AF after RFCA in chronic AF. These DC energy parameters may be related to the chronicity or electroanatomical remodeling of AF.

Number of shocks during elective cardioversion predicts long term recurrence of atrial fibrillation

While the impact of shock energy and number of shocks on the immediate success of direct current cardioversion (DCCV) has been previously studied [1–3], their impact on the long term recurrence of atrial fibrillation (AF) is unclear. In this retrospective study, we assessed the relationship between number of shocks and shock energy and long term AF recurrence. Consecutive patients undergoing successful elective DCCV for persistent AF or atrial flutter (AFL) at our center between October, 2003 and July, 2009 were included.

Role of CHADS2 Score in Evaluation of Thromboembolic Risk and Mortality in Patients With Atrial Fibrillation Undergoing Direct Current Cardioversion (from the ACUTE Trial Substudy)

The CHADS(2) (congestive heart failure, hypertension, age >75 years, diabetes mellitus, stroke or transient ischemic attack [2 points]) scoring scheme has been found to be a good predictor of stroke risk in patients with nonvalvular atrial fibrillation (AF). However, the value of the CHADS(2) scoring system in the risk stratification of patients with AF who undergo direct-current cardioversion has not yet been specifically investigated. In this study, a subgroup of 541 patients from the Assessment of Cardioversion Using Transesophageal Echocardiography (ACUTE) study who had AF for >48 hours and planned to undergo transesophageal echocardiography before direct-current cardioversion were enrolled. Each patient had a CHADS(2) score calculated. Of the patients with CHADS(2) scores of 0, 14 (10%) were found to have left atrial appendage thrombi on transesophageal echocardiography. After 6 months of follow up, patients with CHADS(2) scores of 3 to 6 showed a significantly higher mortality rate in comparison with patients with lower CHADS(2) scores (4.3% vs 0.5%, p = 0.004), despite their similar prevalence of left atrial appendage thrombus and stroke (thrombus: 13.4% vs 11.6%, p = 0.60; stroke: 0% vs 0.3%, p = 0.70). In conclusion, the CHADS(2) scoring system may be useful for predicting short-term mortality risk in patients with AF receiving elective direct-current cardioversion. However, in the preprocedural risk assessment of these patients, the CHADS(2) scoring system is not reliable in predicting risk for left atrial appendage thrombus formation, especially in patients with low CHADS(2) scores.

Prolonged Electrical Quiescence After Direct Current Cardioversion for Atrial Flutter in Congenital Heart Disease

Elective direct current cardioversion is considered first-line treatment in many cases of atrial flutter and fibrillation. This also is true in the pediatric population. This report describes a case of successful cardioversion that resulted in a very prolonged electrical quiescence.

Adjunctive Pharmacotherapy for Elective Direct Current Cardioversion in Patients With Atrial Fibrillation.

BackgroundDirect current cardioversion (DCCV) can restore sinus rhythm in patients with atrial fibrillation (AF), but the long term efficacy is poor. Pharmacological therapies may improve the initial success of the procedure, but whether long term maintenance of sinus rhythm can be improved is unclear. The aim of this study was to evaluate which pharmacotherapies, including antiarrhythmic and renin-angiotensin-aldosterone system (RAAS) inhibiting drugs, most successfully promotes sinus rhythm after elective DCCV in unselected patients with atrial fibrillation.MethodsA retrospective cohort was to study of AF patients attending or DCCV between Jan 2010 and Feb 2012. The data were analysed using multivariate logistical regression models. Initial success of DCCV was the dependent variable in the first analysis. Maintenance of sinus rhythm at follow up was the dependent variable in the second analysis.ResultsOne hundred and thirty patients were included in the first analysis, and 71 patients were included in the second analysis. The only association observed was a positive association between flecainide and an increased odds of maintaining sinus rhythm at follow up (OR 2.14, SE ± 0.93, P = 0.02) .Other antiarrhythmic drugs and RAAS inhibiting drugs had no association with an increased odds of successful DCCV or maintenance of sinus rhythm thereafter.ConclusionsThis is the first study to demonstrate an association between flecainide and a increased odds of maintaining sinus rhythm after DCCV in the long term. This warrants further research, and should be taken into account when choosing adjunctive antiarrhythmic therapy for elective DCCV for AF.

Wolf minimaze operation plus endocardial catheter ablation cured chronic atrial fibrillation (one case report)

Case historyThis is a 61-year-old male patient. He had paroxysmal atrial fibrillation (AF) for about 14 years, refractory to propafanone and amiodarone. AF had persisted for 2 years before Wolf...

Elective Direct Current Cardioversion of Atrial Fibrillation at Hawkes Bay Regional Hospital 2008–2009

Elective Direct Current Cardioversion of Atrial Fibrillation at Hawkes Bay Regional Hospital 2008–2009

Ibutilide for the Cardioversion of Paroxysmal Atrial Fibrillation during Radiofrequency Ablation of Supraventricular Tachycardias

Direct current electrical cardioversion (DC-ECV) is the preferred treatment for the termination of paroxysmal atrial fibrillation (AF) that occurs during radiofrequency ablation (RFA) of supraventricular tachycardias (SVT). Intravenous Ibutilide may be an alternative option in this setting. Thirty-four out of 386 patients who underwent SVT-RFA presented paroxysmal AF during the procedure and were randomized into receiving ibutilide or DC-ECV. Ibutilide infusion successfully cardioverted 16 out of 17 patients (94%) within 17.37 ± 7.87 min. DC-ECV was successful in all patients (100%) within 17.29 ± 3.04 min. Efficacy and total time to cardioversion did not differ between the study groups. No adverse events were observed. RFA was successfully performed in 16 patients (94%) in the ibutilide arm and in all patients (100%) in the DC-ECV arm, p = NS. In conclusion, ibutilide is a safe and effective alternative treatment for restoring sinus rhythm in cases of paroxysmal AF complicating SVT-RFA.

N-3 Polyunsaturated fatty acids for the prevention of arrhythmia recurrence after electrical cardioversion of chronic persistent atrial fibrillation: a randomized, double-blind, multicentre study

Persistent atrial fibrillation (AF) often recurs after direct current electrical cardioversion (ECV). As several experimental and clinical studies suggest that n-3 polyunsaturated fatty acids (PUFAs) may have antiarrhythmic properties even at the atrial level, we aimed to evaluate whether oral supplementation with PUFAs, in addition to conventional antiarrhythmic drugs, could reduce the recurrence rate of the arrhythmia after ECV of persistent AF. Two hundred and four patients (mean age 69.3 years, 33% females) with persistent AF were randomly assigned to receive 3 g/day of PUFAs until ECV and 2 g/day thereafter (104 patients) or placebo (100 patients) for 6 months, beginning at least 1 week before ECV. Selection of conventional antiarrhythmic prophylaxis was left to local medical advice. The cardiac rhythm was assessed by both trans-telephonic monitoring and clinical visits. Primary end-point was the recurrence rate of AF. Sinus rhythm was restored, either spontaneously or after ECV, in 187 patients (91.7%); 95 patients (91.4%) on PUFAs and 92 patients (92.0%) on placebo (P=not significant). AF relapsed in 56 (58.9%) of the PUFAs patients and in 47 (51.1%) of the placebo patients (P=0.28). The mean time to AF recurrence was 83±8 days in the PUFAs group and 106±9 days in the placebo group (P=0.29). Our results do not support the hypothesis that, in patients undergoing ECV of chronic persistent AF, supplementation with PUFAs in addition to the usual antiarrhythmic treatment reduces recurrent AF.

Highlighting patient eligibility for elective DC cardioversion: ‘Jump Start’ a software solution

Atrial fibrillation (AF) is the most frequently encountered sustained cardiac arrhythmia in clinical practice. Medical treatment strategies focus on either heart rhythm control or heart rate control combined with antithrombotic prophylaxis or anticoagulation. If a rhythm control strategy is decided on then transthoracic elective direct current cardioversion is one option for selected patients. Preparing patients for elective direct current cardioversion can present an organizational challenge. This article describes the development and evaluation of a software-based solution to automatically highlight those patients that were eligible for this procedure based on the International Normalized Ratio (INR) blood results entered into the system. In the views of the users, this service development has succeeded in the aim of streamlining the potentially challenging aspect of elective direct current cardioversion anti-thrombotic prophylaxis.

Electrocardiographic Markers of Cardioversion Success in Patients with Atrial Fibrillation

In patients with atrial fibrillation (AF) and atrial flutter (AFL), the value of the 12-lead surface electrocardiogram (ECG) in predicting direct current cardioversion (DCCV) outcomes has not been thoroughly investigated. We sought to determine whether the type of atrial arrhythmia (AF versus AFL) and the characteristics of the atrial fibrillatory waves (fine versus coarse) on the surface ECG would help predict post DCCV outcomes. A total of 76 consecutive patients undergoing elective DCCV for persistent AF or AFL at the Minneapolis Veterans Affairs Medical Center were included in this retrospective cohort study. All patients had ECGs immediately and one month after DCCV. Mean age was 67+/-8 years and 97% of the participants were male. DCCV was immediately successful in 64 (84%) patients. Of these, 35 (46%) remained in sinus rhythm at one month. DCCV was immediately successful in all patients (N 13) with fine AF versus 34/45 of those with coarse AF (P 0.05). Patients with fine AF were also more likely to remain in sinus rhythm at one-month follow up compared to those with coarse AF (8/13 versus 13/45; P 0.03). Also, at one-month follow up, the patients with AFL were more likely to maintain sinus rhythm than those with AF (14/18 of AFL versus 21/58 of AF; P 0.003). The characteristics of the fibrillatory waves on surface ECG should be utilized to determine the success after DCCV in patients with AF and AFL.