Fetal supraventricular tachycardia at 12 weeks of gestation: diagnosis and follow up. A case report

This report describes a case of fetal supraventricular tachycardia (SVT) diagnosed at 12 weeks of gestation in a pregnant woman with diabetes mellitus. Transplacental digoxin therapy administered orally to the mother was unsuccessful. Subsequently, sotalol was added to digoxin to achieve fetal heart rate (HR) control and the conversion to sinus rhythm was achieved. The fetal HR remained stable until term, and a healthy male baby was born. The newborn electrocardiogram showed sinus rhythm with normal PR and QTc intervals. When the newborn was stable, he was discharged with propanolol. Sustained SVT is extremely rare during the first trimester. The goal of treatment in utero is the conversion to sinus rhythm or reduction of the ventricular rate to tolerable levels, preventing or even reversing fetal hydrops.

[Regulatory adaptive status in determining the effectiveness of bisoprololum and sotalolum in patients with hypertensive disease and paroxysmal supraventricular tachycardia]

AIM

To determine efficacy of bisoprolol and sotalol treatments in patients with paroxysmal supraventricular tachycardia (SVT) and essential hypertension (EH) considering effects of these treatments on the regulatory adaptive status (RAS).

MATERIALS AND METHODS

The study included 49 patients with paroxysmal SVT associated with stage II-III EH randomized to two groups of either bisoprolol (6.9±2.2 mg/day, n=25) or sotalol (162.5±46.2 mg/day, n=24) treatment. Lisinopril (14.5±3.9 and 14.3±4.7 mg/day) and, if indicated, atorvastatin (15.4±3.8 mg/day, n=9 and 16.0±4.8 mg/day, n=10), and acetylsalicylic acid (91.5±14.7 mg/day, n=12 and 94.1±16.5 mg/day, n=14) were administered as a part of combination therapy. Quantitative evaluation of RAS (cardiorespiratory synchronism test), EchoCG, triplex scanning of brachiocephalic arteries, treadmill test, 6-min walk test, 24-h BP and ECG monitoring, and subjective assessment of the quality of life were performed at baseline and after 6 months of therapy.

RESULTS

Both regimens of the combination drug therapy comparably improved the structural and functional status of the heart, increased exercise tolerance, effectively suppressed SVT paroxysms, and improved the quality of life. In this process, sotalol reduced RAS to a lesser extent that bisoprolol.

CONCLUSION

In patients with paroxysmal SVT associated with stage II-III EH, the sotalol treatment as a part of the combination therapy may be preferable due to fewer adverse effects on RAS compared to bisoprolol.

Etripamil Nasal Spray for Rapid Conversion of Supraventricular Tachycardia to Sinus Rhythm

BACKGROUND

There is no nonparenteral medication for the rapid termination of paroxysmal supraventricular tachycardia.

OBJECTIVES

The purpose of this study was to assess the efficacy and safety of etripamil nasal spray, a short-acting calcium-channel blocker, for the rapid termination of paroxysmal supraventricular tachycardia (SVT).

METHODS

This phase 2 study was performed during electrophysiological testing in patients with previously documented SVT who were induced into SVT prior to undergoing a catheter ablation. Patients in sustained SVT for 5 min received either placebo or 1 of 4 doses of active compound. The primary endpoint was the SVT conversion rate within 15 min of study drug administration. Secondary endpoints included time to conversion and adverse events.

RESULTS

One hundred four patients were dosed. Conversion rates from SVT to sinus rhythm were between 65% and 95% in the etripamil nasal spray groups and 35% in the placebo group; the differences were statistically significant (Pearson chi-square test) in the 3 highest active compound dose groups versus placebo. In patients who converted, the median time to conversion with etripamil was <3 min. Adverse events were mostly related to the intranasal route of administration or local irritation. Reductions in blood pressure occurred predominantly in the highest etripamil dose.

CONCLUSIONS

Etripamil nasal spray rapidly terminated induced SVT with a high conversion rate. The safety and efficacy results of this study provide guidance for etripamil dose selection for future studies involving self-administration of this new intranasal calcium-channel blocker in a real-world setting for the termination of SVT. (Efficacy and Safety of Intranasal MSP-2017 [Etripamil] for the Conversion of PSVT to Sinus Rhythm [NODE-1]; NCT02296190).

Usefulness of Routine Transtelephonic Monitoring for Supraventricular Tachycardia in Infants

OBJECTIVE

We hypothesize that routine daily transtelephonic monitoring (TTM) transmissions can accurately detect supraventricular tachycardia (SVT) in asymptomatic infants and/or assuage parental concerns rather than being used solely to diagnose arrhythmias.

STUDY DESIGN

Single center, retrospective chart review of 60 patients with fetal or infant SVT prescribed TTM for at least 30 days, January 2010-September 2016. Patients were excluded if initial SVT was not documented, was perioperative, was atrial flutter/fibrillation, or chaotic atrial tachycardia. Categorical variables expressed as mean ± SD. Mann-Whitney, Spearman correlation, and Fisher exact tests were used for continuous and categorical variables respectively.

RESULTS

Sixty patients were included. There were 2688 TTM transmissions received from 55 of 60 patients over 61.1 ± 66.7 days (0.73 ± 0.65 TTM/patient/days). Routine asymptomatic TTM transmissions revealed actionable findings in 5 of 2801 TTM transmissions sent by 5 patients (8.3%). No patient presented in shock or died. Forty-five of 2688 TTM transmissions were sent for parental concerns/symptoms in 16 patients (25.8%) with findings of normal sinus rhythm in 37 of 45 TTM transmissions and SVT in 8 of 45 TTM transmissions. Symptomatic actionable findings were more likely sent by patients discharged on class I or III antiarrhythmics (95% CI = 11.5%-68.3%, P = .004) and patients with prolonged initial hospitalizations (95% CI = 6.98%-59.7%, P = .01). Flecainide was discontinued in 1 patient after widened QRS was noted on routine TTM.

CONCLUSIONS

TTM accurately diagnose asymptomatic recurrent SVT in neonates and infants before they develop signs of congestive heart failure or shock and is helpful for recurrent SVT management.

Adenosine versus intravenous calcium channel antagonists for supraventricular tachycardia

BACKGROUND

People with supraventricular tachycardia (SVT) frequently are symptomatic and present to the emergency department for treatment. Although vagal manoeuvres may terminate SVT, they often fail, and subsequently adenosine or calcium channel antagonists (CCAs) are administered. Both are known to be effective, but both have a significant side effect profile. This is an update of a Cochrane review previously published in 2006.

OBJECTIVES

To review all randomised controlled trials (RCTs) that compare effects of adenosine versus CCAs in terminating SVT.

SEARCH METHODS

We identified studies by searching CENTRAL, MEDLINE, Embase, and two trial registers in July 2017. We checked bibliographies of identified studies and applied no language restrictions.

SELECTION CRITERIA

We planned to include all RCTs that compare adenosine versus a CCA for patients of any age presenting with SVT.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane. Two review authors independently checked results of searches to identify relevant studies and resolved differences by discussion with a third review author. At least two review authors independently assessed each included study and extracted study data. We entered extracted data into Review Manager 5. Primary outcomes were rate of reversion to sinus rhythm and major adverse effects of adenosine and CCAs. Secondary outcomes were rate of recurrence, time to reversion, and minor adverse outcomes. We measured outcomes by calculating odds ratios (ORs) and assessed the quality of primary outcomes using the GRADE approach through the GRADEproGDT website.

MAIN RESULTS

We identified two new studies for inclusion in the review update; the review now includes seven trials with 622 participants who presented to an emergency department with SVT. All included studies were RCTs, but only three described the randomisation process, and none had blinded participants, personnel, or outcome assessors to the intervention given. Moderate-quality evidence shows no differences in the number of people reverting to sinus rhythm who were treated with adenosine or CCA (89.7% vs 92.9%; OR 1.51, 95% confidence interval (CI) 0.85 to 2.68; participants = 622; studies = 7; I² = 36%). Low-quality evidence suggests no appreciable differences in major adverse event rates between CCAs and adenosine. Researchers reported only one case of hypotension in the CCA group and none in the adenosine group (0.66% vs 0%; OR 3.09, 95% CI 0.12 to 76.71; participants = 306; studies = 3; I² = 0%). Included trials did not report length of stay in hospital nor patient satisfaction.

AUTHORS' CONCLUSIONS

Moderate-quality evidence shows no differences in effects of adenosine and calcium channel antagonists for treatment of SVT on reverting to sinus rhythm, and low-quality evidence suggests no appreciable differences in the incidence of hypotension. A study comparing patient experiences and prospectively studied adverse events would provide evidence on which treatment is preferable for management of SVT.

Propafenone for supraventricular arrhythmias in septic shock-Comparison to amiodarone and metoprolol

PURPOSE

The occurence of supraventricular arrhythmias associate with an unfavourable prognosis in septic shock. Propafenone could be a feasible antiarrhythmic.

MATERIALS AND METHODS

Patients collected over a period of 24months were divided into the three groups based on antiarrhythmic: Group1(amiodarone), Group2(propafenone), Group3(metoprolol). Type of arrhythmia, cardioversion rates, demographic, haemodynamic, laboratory parameters were recorded in the first 24h. The outcome data were compared between the groups.

RESULTS

234 patients (99.1% ventilated) were included, the prevailing arrhythmia was acute onset atrial fibrillation (AF,69.7%). Except for the dosage of noradrenaline (0.35(0.14-0.78) in Group1(n=142)vs 0.25(0.10-0.50),p<0.01 in Group2(n=78)vs 0.14(0.07-0.25)μg/kg·min,p<0.05 in Group3(n=14)) the ejection fraction of left ventricle, rates of renal replacement therapy, arterial lactate and procalcitonin levels were not different between the groups. The cardioversion rate in Group1(74%) was lower than in Group2(89%) and Group3(92%). ICU and 28-day mortalities of Group1 were not significantly higher than in Group2 and Group3. Multivariate analysis demonstrated higher 12-month mortality in Group1 than in Group2 (HR1.58(1.04;2.38),p=0.03).

CONCLUSIONS

Propafenone demonstrated a higher cardioversion rate than amiodarone with a similar impact on the outcome. Patients remaining in acute onset arrhythmia did not demonstrate significantly higher ICU, 28-day and 12-month mortalities compared to those successfully cardioverted or to those having chronic AF.

Antenatal antiarrhythmic treatment for fetal tachyarrhythmias: a study protocol for a prospective multicentre trial

INTRODUCTION

Several retrospective or single-centre studies demonstrated the efficacy of transplacental treatment of fetal tachyarrhythmias. Our retrospective nationwide survey showed that the fetal therapy will be successful at an overall rate of 90%. For fetuses with hydrops, the treatment success rate will be 80%. However, standard protocol has not been established. The objective of this study is to evaluate the efficacy and safety of the protocol-defined transplacental treatment of fetal tachyarrhythmias. Participant recruitment began in October 2010.

METHODS AND ANALYSIS

The current study is a multicentre, single-arm interventional study. A total of 50 fetuses will be enrolled from 15 Japanese institutions. The protocol-defined transplacental treatment is performed for singletons with sustained fetal tachyarrhythmia ≥180 bpm, with a diagnosis of supraventricular tachycardia or atrial flutter. Digoxin, sotalol, flecainide or a combination is used for transplacental treatment. The primary endpoint is disappearance of fetal tachyarrhythmias. The secondary endpoints are fetal death related to tachyarrhythmia, proportion of preterm birth, rate of caesarean section attributable to fetal arrhythmia, improvement in fetal hydrops, neonatal arrhythmia, neonatal central nervous system disorders and neonatal survival. Maternal, fetal and neonatal adverse events are evaluated at 1 month after birth. Growth and development are also evaluated at 18 and 36 months of corrected age.

ETHICS AND DISSEMINATION

The Institutional Review Board of the National Cerebral and Cardiovascular Center of Japan has approved this study. Our findings will be widely disseminated through conference presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBER

UMIN Clinical Trials Registry UMIN000004270.

Neonatal complex arrhythmias possibly related to a TTN mutation

We describe a neonate born with complex arrhythmias that included concurrent atrial and ventricular tachycardias. Genetic testing demonstrated a mutation in the TTN gene, which codes for titin, a large protein found in striated muscle sarcomeres. The complex arrhythmias were successfully treated with amiodarone and flecainide. The patient remains asymptomatic with normal biventricular function. We speculate that the complex arrhythmias and TTN gene mutation may be related.

[Anesthetic Management of a Patient who Developed Intraoperative Paroxysmal Supraventricular Tachycardia with Pulseless Electric Activity]

A 75-year-old woman was scheduled to undergo an ileus operation under general combined with epidural anesthesia. Preoperative electrocardiogram (ECG) showed first-degree atrioventricular block. The patient received no preoperative antiarrhythmic medication. During surgery, paroxysmal supraventricular tachycardia (PSVT) occurred unexpectedly with radial artery pulsation disappearing, indicating pulseless electric activity (PEA). After a five-second episode of PSVT, her sinus rhythm recovered spontaneously. However, the patient had repeated short duration of PSVT with PEA. Continuous infusion of ultra-short-acting β-blocker landiolol successfully terminated the PSVT, and sinus rhythm was restored. Postoperative ECG showed sinus rhythm. This case report indicates that β-blocker can be a drug of choice in patients with PSVT associated with PEA.

Supraventricular tachyarrhythmias in the intensive care unit

Several types of supraventricular tachyarrhythmias occur commonly during intensive care. The specific type can usually be diagnosed using standard electrocardiographic techniques. Several new drugs have significantly improved the ability to successfully manage these arrhythmias.

Fetal and Neonatal Arrhythmias

Cardiac arrhythmias are an important aspect of fetal and neonatal medicine. Premature complexes of atrial or ventricular origin are the main cause of an irregular heart rhythm. The finding is typically unrelated to an identifiable cause and no treatment is required. Tachyarrhythmia most commonly relates to supraventricular reentrant tachycardia, atrial flutter, and sinus tachycardia. Several antiarrhythmic agents are available for the perinatal treatment of tachyarrhythmias. Enduring bradycardia may result from sinus node dysfunction, complete heart block and nonconducted atrial bigeminy as the main arrhythmia mechanisms. The management and outcome of bradycardia depend on the underlying mechanism.

Diagnosis and Management of Common Types of Supraventricular Tachycardia

Supraventricular tachycardia refers to rapid rhythms that originate and are sustained in atrial or atrioventricular node tissue above the bundle of His. The condition is caused by reentry phenomena or automaticity at or above the atrioventricular node, and includes atrioventricular nodal reentrant tachycardia, atrioventricular reciprocating tachycardia, and atrial tachycardia. Most persons with these tachyarrhythmias have structurally normal hearts. Sudden onset of an accelerated heart rate can cause palpitations, light-headedness, chest discomfort, anxiety, dyspnea, or fatigue. The history is important to elicit episodic symptoms because physical examination and electrocardiography findings may be normal. A Holter monitor or event recorder may be needed to confirm the diagnosis. Vagal maneuvers may terminate the arrhythmia; if this fails, adenosine is effective in the acute setting. Calcium channel blockers (diltiazem or verapamil) or beta blockers (metoprolol) can be used acutely or as long-term therapy. Class Ic antiarrhythmics (flecainide or propafenone) can be used long-term. Class Ia antiarrhythmics (quinidine, procainamide, or disopyramide) are used less often because of their modest effectiveness and adverse effects. Class III antiarrhythmics (amiodarone, sotalol, or dofetilide) are effective, but have potential adverse effects and should be administered in consultation with a cardiologist. Catheter ablation has a success rate of 95% and recurrence rate of less than 5%, and causes inadvertent heart block in less than 1% of patients. It is the preferred treatment for symptomatic patients with Wolff-Parkinson-White syndrome.

Challenges in IPF diagnosis, current management and future perspectives: Patient case 2

PATIENT PRESENTATION AND DIAGNOSIS: The patient is a 73-year-old male retired house painter and ex-smoker who was admitted to the respiratory medicine department of a district hospital in Greece due to the presence of streaks of blood in his sputum. His past medical history included coronary artery disease, arterial hypertension and supraventricular tachycardia (SVT). A high resolution computed tomography (HRCT) was performed which showed enlarged mediastinal lymph nodes with evidence of fibrosis.

Treatment of supraventricular tachycardia in infants: Analysis of a large multicenter database

OBJECTIVE

Supraventricular tachycardia (SVT) is the most common arrhythmia in infants. Infants are typically treated with antiarrhythmic medications, but there is a lack of evidence guiding management, thus exposing infants to risks of both inadequate therapy and medication adverse events. We used data from a large clinical database to better understand current practices in SVT management, safety of commonly used medications, and outcomes of hospitalized infants treated for SVT.

METHODS

This retrospective data analysis included all infants discharged from Pediatrix Medical Group neonatal intensive care units between 1998 and 2012 with a diagnosis of SVT who were treated with antiarrhythmic medications. We categorized infants by the presence of congenital heart disease other than patent ductus arteriosus. Medications were categorized as abortive, acute, or secondary prevention therapies. We used descriptive statistics to describe medication use, adverse events, and outcomes including SVT recurrence and mortality.

RESULTS

A total of 2848 infants with SVT were identified, of whom 367 (13%) had congenital heart disease. Overall, SVT in-hospital recurrence was high (13%), and almost one fifth of our cohort (18%) experienced an adverse event. Mortality was 2% in the overall cohort and 6% in the congenital heart disease group (p<0.001). Adenosine was the most commonly used abortive therapy, but there was significant practice variation in therapies used for acute treatment and secondary prevention of SVT.

CONCLUSION AND PRACTICE IMPLICATION

Significant variation in SVT treatment and suboptimal outcomes warrant future clinical trials to determine best practices in treating SVT in infants.

[Clinical course and treatment of ectopic atrial tachycardia in 144 children]

OBJECTIVE

Ectopic atrial tachycardia (EAT) is a common type of supraventricular tachycardia in pediatric population, and it can be resistant to antiarrhythmic drugs and lead to tachycardia induced cardiomyopathy (TIC) if not properly managed. This study assessed the clinical course and response to treatment of EAT in children.

METHOD

A retrospective review included 144 children at the First Hospital of Tsinghua University diagnosed with EAT from January 2009 to April 2014. The clinical detailed history, 12 lead ECG, 24-h Holter recording, echocardiography, response to therapy and follow-up were analyzed.

RESULT

The onset of EAT occurred at any age with a distribution with positive skewness, 57 children ≤1 years, 22 children > 1 - 3 years, 25 children > 3 - 6 years and 40 children ≥ 6 years of age. The percentages of the three tachycardia types were 36. 1% (n = 52) for incessant EAT, 52. 8% (n = 76) for paroxysmal EAT and 11. 1% (n = 16) for sporadic EAT, respectively. There were 115 patients received drug therapy in our hospital and in 72 cases the EAT was completely controlled. Antiarrhythmic therapy had been discontinued in 35 children with complete control. Normal sinus rhythm was observed by telemetry or Holter within 4 to 90 days and the mean duration of medical therapy was 310 days (range 15 to 608 days) in these children. The combination of sotalol and propafenone showed better effectiveness for control of children with EAT (54%, 41/76), compared with single sotalol (36%, 24/66) and the combination of amiodarone and metoprolol (30%, 7/23) (χ2 = 6. 296, P = 0. 043). Tachycardia type was able to predict the response to antiarrhythmic drugs for children with EAT, sporadic tachycardia had best control rate on pharmacological therapy compared with paroxysmal tachycardia and incessant tachycardia (94% (15/16) vs. 67% (42/63) vs. 42% (15/36), χ2 = 17. 925, P = 0. 000) . Acute success of radiofrequency ablation (RFA) in children who showed poor response to antiarrhythmic drugs was achieved in 45 of 49 (92%), ultimate success was achieved in 33 of 49 (67%). The incidence of TIC secondary to EAT was 18. 1% (n =26), and left ventricular ejection-fraction (LVEF) returned to normal in 23 children after successful control of EAT ((61 ± 4) % vs. (43 ± 5) %, t = - 10. 036, P = 0. 000). Side effects including abnormal thyroid function (in 3) and abnormal liver function (in 1) occurred in 4 (17%) of 23 children who received amiodarone and disappeared when amiodarone was discontinued.

CONCLUSION

EAT in children predominantly occurred in young infants and children. Incessant EAT comprised a great percentage. The combination of sotalol and propafenone provided the best results for control of children with EAT. RFA should be considered as a preferred treatment for older children who displayed poor response to medical therapy.

[ETACISIN-INDUCED BRUGADA SYNDROME IN A PATIENT WITH LONG-STANDING SUPRAVENTRICULAR EXTRASYSTOLE]

Brugada syndrome is a commonest cause of malignant disorders of cardiac rhythm associated with sudden death. It is diagnosed based on characteristic ECG signs and ventricular arrhythmia. This paper reports a 49 year-old patient with long-standing latent BS manifest as supraventricular and transient blockade of the right branch of the His bundle. The ECG pattern of BS became apparent in association with a 7 day treatment with class IC antiarrhythmic agent etacisin. Diagnostic difficulties account for the fact that the disease was initially described as myocardial infarction. Diagnosis of BS was confirmed by an electrophysiological study in which stable ventricular tachycardia and fibrillation were induced by etacisin. A cardioverter defibrillator was implanted to the patient.

Comparative effectiveness of digoxin and propranolol for supraventricular tachycardia in infants

OBJECTIVES

Supraventricular tachycardia is the most common arrhythmia in infants, and antiarrhythmic medications are frequently used for prophylaxis. The optimal prophylactic antiarrhythmic medication is unknown, and prior randomized trials have been underpowered. We used data from a large clinical registry to compare efficacy and safety of digoxin and propranolol for infant supraventricular tachycardia prophylaxis. We hypothesized that supraventricular tachycardia recurrence is less common on digoxin when compared with propranolol.

DESIGN

Retrospective cohort study.

SETTING

Pediatrix Medical Group neonatal ICUs.

PATIENTS

Infants discharged from 1998 to 2012 with supraventricular tachycardia who were treated with digoxin or propranolol. We excluded infants discharged before completing 2 days of therapy, those with Wolff-Parkinson-White syndrome, structural heart defects (except atrial/ventricular septal defects and patent ductus arteriosus), and those started on multidrug therapy.

MEASUREMENTS AND MAIN RESULTS

We used Cox proportional hazards to evaluate supraventricular tachycardia recurrence, defined as need for adenosine or electrical cardioversion while exposed to digoxin versus propranolol, controlling for infant characteristics, inotropic support, supplemental oxygen, and presence of a central line. We identified 342 infants exposed to digoxin and 142 infants exposed to propranolol. The incidence rate of treatment failure was 6.7/1,000 infant-days of exposure to digoxin and 15.4/1,000 infant-days of exposure to propranolol. On multivariable analysis, treatment failure was higher on propranolol when compared with that on digoxin (hazard ratio, 1.97; 95% CI, 1.05-3.71). Hypotension was more frequent during exposure to digoxin versus propranolol (39.4 vs 11.1/1,000 infant-days; p < 0.001). There was no difference in frequency of other clinical adverse events.

CONCLUSIONS

Digoxin was associated with fewer episodes of supraventricular tachycardia recurrence but more frequent hypotension in hospitalized infants relative to propranolol.

Supraventricular tachycardia in infancy and childhood

Supraventricular tachycardia (SVT) is the most common arrhythmia in the pediatric population. Despite its commonality, presentation of SVT can be nonspecific and varies based upon age with infants demonstrating fussiness or irritability and older children reporting vague perceptions of tachycardia or palpitations. Furthermore, SVT may manifest as self-limited paroxysms or with prolonged runs of SVT with subsequent development of cardiac dysfunction, heart failure, and multiorgan shock. Clinicians must maintain high levels of suspicion for SVT given the potentially dire consequences of untreated SVT. When diagnosed, there are effective acute and chronic treatments for SVT, with potential for spontaneous resolution in many infants.

[Digoxin intoxication in an infant because of confusion of bottles of magistral preparations of medicine]

We hereby describe a case report of a 9-month-old girl, who was accidentally intoxicated with digoxin since her parents by mistake gave her digoxin instead of propranolol. At admission sinusbradycardia and a first-degree atrioventricular block was found and she was treated with antidigitalis Fab-fragment and atropine. After three days of hospitalization she was discharged well-being. We suspect that the explanation for this intoxication is due to confusion of bottles of magistral preparations of medicine, as they were very identical. Therefore we call for increased attention in children receiving this type of medicine.

[Novel class III antiarrhythmic agent niferidile: review of experimental and clinical studies]

This article reviews experimental and clinical studies of a novel antiarrhythmic agent niferidile. Niferidile, a class III antiarrhythmic agent, blocks potassium outward currents, prolongs repolarization and refractory periods predominantly in atria than in ventricles. Intravenous Niferidile was efficient for interruption of AV-nodal and orthodromic re-entrant tachycardias with rates of 75% to 80%. Niferidile had a conversion rate of up to 87.3% in persistent atrial fibrillation and up to 100% in persistent atrial flutter. Proarrhythmic action of niferidil administration manifested as nonsustained torsade de pointes and monomorphic ventricular tachycardia in 1.2 and 3.7% of cases, respectively. Niferidile can be used for pharmacological cardioversion of persistent atrial fibrillation and flutter as an alternative to electrical cardioversion.

Randomised Evaluation of modified Valsalva Effectiveness in Re-entrant Tachycardias (REVERT) study

INTRODUCTION

The Valsalva manoeuvre (VM) is a recommended first-line physical treatment for patients with re-entrant supraventricular tachycardia (SVT), but is often ineffective in standard practice. A failed VM is typically followed by treatment with intravenous adenosine, which patients often find unpleasant. VM effectiveness might be improved by a modification to posture which exaggerates the manoeuvre's vagal response and reduces the need for further emergency treatment.

METHODS AND ANALYSIS

This is a multicentre randomised controlled clinical trial in 10 UK emergency departments (EDs). It compares a standard VM with a modified VM incorporating leg elevation and a supine posture after a standardised strain in stable adult patients presenting to the ED with SVT. The primary outcome measure is return to sinus rhythm on a 12-lead ECG. Secondary outcome measures include the need for treatment with adenosine or other antiarrhythmic treatments and the time patients spend in the ED. We plan to recruit approximately 372 patients, with 80% power to demonstrate an absolute improvement in cardioversion rate of 12%. An improvement of this magnitude through the use of a modified VM would be of significant benefit to patients and healthcare providers, and justify a change to standard practice.

ETHICS AND DISSEMINATION

The study has been approved by the South West-Exeter Research Ethics Committee (REC reference 12/SW/0281). The trial will be published in an international peer reviewed journal. Study findings will be sent to the European and International resuscitation councils to inform future revisions of arrhythmia management guidelines.

RESULTS

The trial will also be disseminated at international conferences and to patients through the Arrhythmia Alliance, a patient support charity.

REGISTRATION

The study is registered with Current Controlled Trials (ISRCTN67937027) and has been adopted by the National Institute for Health Research (NIHR) Clinical Research Network.