Conversion Of Fibrillation Research Articles

Conversion of Atrial Fibrillation During Pulmonary Vein Isolation: Time to Stop and Have a Rest?

Conversion of Atrial Fibrillation During Pulmonary Vein Isolation: Time to Stop and Have a Rest?

A Comparative Study of the Efficacy and Safety of Procainamide Versus Propafenone Versus Amiodarone for the Conversion of Recent-Onset Atrial Fibrillation

The appropriate treatment for the restoration of sinus rhythm in patients with atrial fibrillation (AF) of recent onset is still the subject of controversy. In this prospective, randomized, single-blind, placebo-controlled clinical study, we investigated the effectiveness and safety of procainamide, propafenone, and amiodarone, administered intravenously, for the conversion of recent-onset AF. We enrolled 362 consecutive patients (183 men; age 34 to 86 years; mean 65+/-10) with AF duration of no >48 hours. Of these patients, 89 were given procainamide, 91 propafenone, 92 amiodarone, and 90 placebo. Treatment was considered successful if conversion to sinus rhythm was achieved within the 24-hour study period. Baseline clinical characteristics were similar in the 4 groups. The treatment was successful in 61 of the 89 patients who received procainamide (68.53%; median time 3 hours), 73 of the 91 patients who received propafenone (80.21%; median time 1 hour), 82 of the 92 patients who received amiodarone (89.13%; median time 9 hours), and 55 of the 90 patients who received placebo (61.11%; median time 17 hours; p<0.05 for all medicated groups vs placebo; p<0.05 for amiodarone and propafenone vs procainamide). In conclusion, all 3 medications, when administered intravenously, are effective in the restoration of sinus rhythm in recent-onset AF. Amiodarone and propafenone are more effective whereas procainamide and propafenone are faster.

Transient syncope, left bundle branch block and first degree atrioventricular block after “pill-in-the-pocket” administration

The single oral loading dose of propafenone appears to be highly effective for conversion of recent-onset atrial fibrillation (AF), with a relatively rapid effect within 2 to 3 h and freedom from serious adverse effects [1]. Administration of flecainide, dofetilide, propafenone, or ibutilide is recommended for pharmacological cardioversion of AF (Class I Level of Evidence: A). A single oral bolus dose of propafenone or flecainide (“pill-in-the-pocket”) can be administered to terminate persistent AF outside the hospital once treatment has proved safe in hospital for selected patients without sinus or atrioventricular (AV) node dysfunction, bundle-branch block, QT-interval prolongation, the Brugada syndrome, or structural heart disease.

Vernakalant (RSD1235): a novel, atrial-selective antifibrillatory agent

This review summarizes the mechanistic properties and the recent experience in the development of a new antiarrhythmic agent, RSD1235 (recently named vernakalant), for the acute conversion of atrial fibrillation to sinus rhythm. Atrial fibrillation is the most common sustained cardiac arrhythmia that is observed in clinical practice and is associated with increased morbidity and mortality, resulting from stroke and exacerbation of heart failure. At present, there is a lack of pharmacologic agents that are able to safely and effectively convert the arrhythmia back to sinus rhythm. Vernakalant has the electrophysiologic properties of a multiple ion channel blocker, developed using a novel approach to target potassium channels that are selectively present in human atria rather than ventricles, and using a rate-dependent blocking strategy for its additional sodium channel block. This paper reviews the mechanism of action of this drug, its performance in preclinical models of efficacy and human disease, and its actions on patients in the completed and published preregistration clinical trials for vernakalant. Overall, vernakalant converted 51.5% of patients who had < 7 days duration of atrial fibrillation and it did this without significantly more cardiovascular adverse events than placebo. Therefore, it must be considered as an important new agent for the treatment of this growing health problem.

BIPHASIC Trial

There is little clear evidence as to the optimal energy levels for initial and subsequent shocks in biphasic waveform defibrillation. The present study compared fixed lower- and escalating higher-energy regimens for out-of-hospital cardiac arrest. The Randomized Controlled Trial to Compare Fixed Versus Escalating Energy Regimens for Biphasic Waveform Defibrillation (BIPHASIC Trial) was a multicenter, randomized controlled trial of 221 out-of-hospital cardiac arrest patients who received > or = 1 shock given by biphasic automated external defibrillator devices that were randomly programmed to provide, blindly, fixed lower-energy (150-150-150 J) or escalating higher-energy (200-300-360 J) regimens. Patient mean age was 66.0 years; 79.6% were male. The cardiac arrest was witnessed in 63.8%; a bystander performed cardiopulmonary resuscitation in 23.5%; and initial rhythm was ventricular fibrillation/ventricular tachycardia in 92.3%. The fixed lower- and escalating higher-energy regimen cases were similar for the 106 multishock patients and for all 221 patients. In the primary analysis in multishock patients, conversion rates differed significantly (fixed lower, 24.7%, versus escalating higher, 36.6%; P=0.035; absolute difference, 11.9%; 95% CI, 1.2 to 24.4). Ventricular fibrillation termination rates also were significantly different between groups (71.2% versus 82.5%; P=0.027; absolute difference, 11.3%; 95% CI, 1.6 to 20.9). For the secondary analysis of first shock success, conversion rates were similar between the fixed lower and escalating higher study groups (38.4% versus 36.7%; P=0.92), as were ventricular fibrillation termination rates (86.8% versus 88.8%; P=0.81). There were no distinguishable differences between regimens for survival outcomes or adverse effects. This is the first randomized trial to compare fixed lower and escalating higher biphasic energy regimens in out-of-hospital cardiac arrest, and it demonstrated higher rates of ventricular fibrillation conversion and termination with an escalating higher-energy regimen for patients requiring multiple shocks. These results suggest that patients in ventricular fibrillation benefit from higher biphasic energy levels if multiple defibrillation shocks are required.

Echocardiographic Evidence of Left Atrial Mechanical Dysfunction after Conversion of Atrial Fibrillation to Sinus Rhythm in 5 Horses

Atrial contractile dysfunction occurs in some species after conversion of atrial fibrillation (AF) to normal sinus rhythm (NSR) but has not been reported in horses with naturally occurring AF. Transthoracic echocardiography allows detection of left atrial (LA) mechanical dysfunction in horses after conversion of AF to NSR. Five Standardbreds with AF and 6 healthy Standardbreds of similar age, weight, and athletic condition were included in this study. Four horses were treated pharmacologically (quinidine), and 1 horse was treated by means of transvenous electrical cardioversion. Echocardiographic examinations were performed in normal horses (once) and in AF horses (24 hours and 72 hours after conversion to NSR) by means of 2-dimensional echocardiography (2DE), transmitral flow Doppler, and tissue Doppler imaging (TDI) techniques. Echocardiographic indices of LA mechanical function were compared between normal horses and AF horses. Two-dimensional echocardiography and TDI indices of LA mechanical function revealed significant decreases in LA contractile function and LA reservoir function 24 hours after cardioversion. This decrease was no longer statistically significant 72 hours after cardioversion, but changes in echocardiographic variables between 24 and 72 hours varied among horses. LA contractile dysfunction can be evaluated in horses by use of 2DE, transmitral Doppler flow velocity profiles, and analyses of LA wall motion by TDI. The results of this study are consistent with AF-induced atrial remodeling, although residual treatment effects or influence of underlying primary myopathy cannot be excluded.

Dofetilide: a new class III antiarrhythmic agent

Dofetilide is a relatively new class III antiarrhythmic agent that selectively blocks the rapid component of the cardiac ion channel delayed rectifier current. This results in an increase in the action potential duration and effective refractory period of the myocyte, thereby terminating reentrant tachyarrhythmias and preventing their re-induction. Oral dofetilide is effective in the conversion of atrial fibrillation and flutter to sinus rhythm and in the maintenance of sinus rhythm after conversion. It is generally well tolerated but like other antiarrhythmic agents in its class, torsades de pointes may be induced as a consequence of therapy. This risk is minimized by dosage adjustment according to creatinine clearance and QTc interval, by selecting patients without known risk factors for torsades and by initiating treatment in a monitored hospital setting for the first 3 days. Unlike other antiarrhythmic agents, oral dofetilide did not increase mortality in patients with a recent myocardial infarction or congestive heart failure, hence its importance as an alternative medication for the pharmacological conversion of atrial fibrillation and flutter, and maintenance of sinus rhythm after conversion in patients at high risk of sudden death.

Vernakalant

Vernakalant

Long-term efficacy and safety of very-low-dose amiodarone treatment for the maintenance of sinus rhythm in patients with chronic atrial fibrillation after successful direct-current cardioversion

Long-term maintenance of sinus rhythm after successful conversion of chronic atrial fibrillation (CAF), often ameliorates patients' symptoms, reduces the risk of ischemic stroke and improves cardiovascular hemodynamics. This prospective study aims to evaluate the long-term efficacy and safety of very low-dose amiodarone (100 mg daily) for the maintenance of sinus rhythm after successful direct-current (DC) cardioversion in patients with CAF and rheumatic heart disease (RHD) post intervention. This study was a randomized prospective trial. One day after successful DC cardioversion (remained normal sinus rhythm) in patients with CAF and RHD post intervention for more than six months and adequate anticoagulation, all were randomly administered either amiodarone 200 mg daily in group A or amiodarone 100 mg daily in group B. A total of 76 patients (40 men and 36 women) were examined from February 1998 to December 1999. The mean age of the patients was (66 +/- 10) years, and the mean follow-up was (67 +/- 8) months (range 61 to 84 months). Actuarial rates of the maintenance of sinus rhythm were similar in the two groups after 5 years of follow-up. Four patients (11%) in group A but none in group B experienced significant adverse effects that necessitated withdrawal of amiodarone. No death occurred during the study period. A very low dose of amiodarone results in adequate long-term efficacy and is safe for maintaining sinus rhythm in patients with CAF and RHD post intervention after successful DC cardioversion.

Atrial Fibrillation with Hyperthyroidism in a 14-Year-Old Male

Atrial fibrillation is an uncommon feature of hyperthyroidism in childhood. We report a 14-year-old male who was referred to our hospital with hyperthyroidism and atrial fibrillation. He had a family history of atrial fibrillation. Spontaneous conversion of atrial fibrillation to sinus rhythm occurred 20 weeks after achieving euthyroid state by an antithyroid agent and a beta-blocker. Atrial fibrillation reoccurred after reduction of antithyroid medication and persisted for 19 weeks. Successful electrical cardioversion was performed resulting in conversion of heart rhythm to sinus. Usually, hyperthyroidism associated atrial fibrillation spontaneously reverts to sinus rhythm several weeks after achieving a euthyroid state. Control of thyroid function and heart rate is the goal of therapy for this type of atrial fibrillation.

148: RSD1235 Effectively Converts Acute Atrial Fibrillation to Sinus Rhythm Independent of Background Use of Oral Rate- or Rhythm-Control Medications

RSD1235 is a novel, frequency-dependent Na+ and early activating K+ channel blocker that selectively prolongs the atrial refractory period. The efficacy and safety of intravenous RSD1235 for conversion of atrial fibrillation (AF) to sinus rhythm (SR) were evaluated in 2 multicenter, randomized, placebo-controlled Atrial Arrhythmia Conversion Trials (ACT I and ACT III). Reported here is a pooled analysis of patients with acute AF from ACT I and ACT III, which assessed the efficacy and safety of RSD1235 in patients using concomitant rate- or rhythm-control medication.

Acute Conversion of Atrial Fibrillation in Two Dogs by Intravenous Amiodarone Administration

Journal of Veterinary Internal MedicineVolume 20, Issue 5 p. 1224-1227 Open Access Acute Conversion of Atrial Fibrillation in Two Dogs by Intravenous Amiodarone Administration Mark A. Oyama DVM, DACVIM-Cardiology, Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL. Department of Clinical Sciences, MJR-VHUP-Cardiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA. Department of Clinical Sciences, MJR-VHUP-Cardiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104; e-mail: maoyama@vet.upenn.edu.Search for more papers by this authorRobert Prosek, Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL. Department of Small Animal Clinical Sciences, Veterinary Medical Center, University of Florida, Gainesville, FL.Search for more papers by this author Mark A. Oyama DVM, DACVIM-Cardiology, Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL. Department of Clinical Sciences, MJR-VHUP-Cardiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA. Department of Clinical Sciences, MJR-VHUP-Cardiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104; e-mail: maoyama@vet.upenn.edu.Search for more papers by this authorRobert Prosek, Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL. Department of Small Animal Clinical Sciences, Veterinary Medical Center, University of Florida, Gainesville, FL.Search for more papers by this author First published: 05 February 2008 https://doi.org/10.1111/j.1939-1676.2006.tb00727.xCitations: 13 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Citing Literature Volume20, Issue5September 2006Pages 1224-1227 ReferencesRelatedInformation

Atrial fibrillation: Choosing an antiarrhythmic drug

Atrial fibrillation is the most common arrhythmia encountered in clinical practice. The associated hemodynamic changes can lead to symptoms of palpitations, fatigue, light-headedness, or dyspnea. Extensive research in the use of antiarrhythmic drugs has been performed both to facilitate the conversion of atrial fibrillation to sinus rhythm and to maintain normal sinus rhythm. The relative merits of a rhythm control versus rate control strategy are briefly discussed. Efficacy of the available agents for pharmacologic cardioversion is reviewed in detail. Important drugs for maintenance of sinus rhythm include amiodarone, flecainide, propafenone, sotalol, and dofetilide. Selection of the appropriate antiarrhythmic drug must be individualized to the clinical situation, with Class IC drugs being first-line agents in the absence of structural heart disease. Regardless of agent selected, appropriate monitoring for development of adverse effects is of utmost importance.

Safe and effective conversion of persistent atrial fibrillation to sinus rhythm by intravenous AZD7009

Acute drug conversion of persistent atrial fibrillation usually fails. The purpose of this study was to test the proarrhythmic potential, safety, and efficacy of the novel antiarrhythmic agent AZD7009 in patients with persistent atrial fibrillation (AF) or atrial flutter (mean duration 43 days) scheduled for direct current (DC) cardioversion. Patients were randomized to AZD7009 (3-hour intravenous infusion; n = 86) or placebo (n = 36). AZD7009 was given in doses intended to produce target pseudo-steady-state plasma levels of 0.25, 0.50, 0.75, 1.0, 1.5, 2.0, or 2.5 micromol/L after 30 minutes of infusion. DC cardioversion was performed if conversion to sinus rhythm (SR) did not occur within 2 hours of infusion. AZD7009 in a concentration-dependent manner increased the rate of conversion of AF to SR and shortened the time to conversion. At the three highest target concentrations of AZD7009, 45%, 64%, and 70% of AF patients converted after a mean time of 62, 55, and 26 minutes, respectively, whereas no placebo-treated patients converted. SR was maintained for 24 hours in 21 of 22 patients with drug-associated conversion. AZD7009 treatment was associated with QT-interval prolongation; the increase in QT corrected according to Fridericia typically ranged from 40 to 80 ms at targeted pseudo-steady-state plasma concentrations >or=0.75 micromol/L, but a number of outliers with QT corrected according to Fridericia >550 ms were seen in the higher concentration groups, particularly after conversion to SR and prolonged infusion. None of the patients exhibited torsades de pointes according to predefined criteria; however, one patient exhibited a nonsustained, polymorphic ventricular tachycardia of eight beats with torsades de pointes-like features after AZD7009 infusion (asymptomatic and discovered only upon retrospective Holter tape analysis). Clinical adverse events (primarily dizziness, bradycardia, hypotension, and nausea) were significantly more common in the highest target concentration AZD7009 group vs placebo (P <.001). AZD7009 exhibited dose-dependent effects in converting AF to SR in AF patients and appeared to be associated with a low risk of proarrhythmia despite continued administration during a period of heightened vulnerability.

Ibutilide to expedite ED therapy for recent-onset atrial fibrillation flutter

Objective Ibutilide is a type III antiarrhythmic agent approved for the pharmacologic conversion of atrial fibrillation (AF) and atrial flutter (AFl). Previous studies conducted outside the ED setting have demonstrated conversion rates of 60% to 80%. This response has been highest in patients with recent-onset AF-AFl. These observations and the 4-hour half-life of ibutilide suggest that it may be an excellent drug with which to treat AF-AFl in the ED. The purpose of the study was to examine the efficacy and safety of ibutilide in terminating AF-AFl in patients who present to the ED with symptoms of less than 3 days' duration, neither angina nor heart failure, and no comorbid conditions that require admission. Methods Among 36 enrolled patients, the admission electrocardiogram demonstrated AF in 26 and AFl in 10. Ibutilide 1 mg was administered intravenously for 10 minutes. If sinus rhythm was not present 10 minutes after the infusion concluded, a second infusion of 1 mg was given. Successful conversion was defined as restoration of sinus rhythm within 1 hour after the last dose of ibutilide. Results Sixteen (61.5%) of 26 patients with AF and 9 (90%) of 10 patients with AFl converted to sinus rhythm (overall conversion rate = 69%). The mean time to arrhythmia termination was 19 ± 9 minutes. The mean stay in the ED was 16.2 hours. No significant complications occurred. Conclusion We conclude that ibutilide is an excellent therapy option for restoring sinus rhythm in the ED. Its use may obviate the need for admission, avoid the risks and inconveniences of general anesthesia to perform electrical cardioversion, and reduce the ED length of stay in selected patients with recent-onset atrial arrhythmias.

The Role of Late INa and Antiarrhythmic Drugs in EAD Formation and Termination in Purkinje Fibers

Multiple components of cardiac Na current play a role in determining electrical excitation in the heart. Recently, the role of nonequilibrium components in controlling cardiac action potential plateau duration, and their importance in regulating the occurrence of afterdepolarizations and arrhythmias have garnered more attention. In particular, late Na current (late I(Na)) has been shown to be important in LQT2 and LQT3 arrhythmias. Class III agents like dofetilide, clofilium, and sotalol, which can all cause a drug-induced form of LQT2, significantly lengthen action potential duration at 50% and 90% repolarization in isolated rabbit Purkinje fibers, and can initiate the formation of early afterdepolarizations, and extra beats. These actions can lead to the development of a serious ventricular tachycardia, torsades de pointes, in animal models and patients. However, pretreatment with agents that block late I(Na), like lidocaine, mexiletine, and RSD1235, a novel mixed ion channel blocker for the rapid pharmacologic conversion of atrial fibrillation, significantly attenuates the prolonging effects of Class III agents or those induced by ATX-II, a specific toxin that delays Na channel inactivation and amplifies late I(Na) greatly, mimicking LQT3. The Na channel block caused by lidocaine and RSD1235 can be through the open or inactivated states of the channel, but both equivalently inhibit a late component of Na current (I(Na)), recorded at 22 degrees C using whole-cell patch clamp of Nav 1.5 expressed in HEK cells. These protective actions of lidocaine, mexiletine, and RSD1235 may result, at least in part, from their ability to inhibit late I(Na) during action potential repolarization, and inhibition of the inward currents contributing to EAD and arrhythmia formation.

Efficacy and Safety of Ibutilide for the Conversion of Monomorphic Atrial Tachycardia

Ibutilide is a class III antiarrhythmic drug, frequently used for conversion of atrial fibrillation and flutter. We studied the efficacy of ibutilide for acute conversion of monomorphic atrial tachycardia (monoAT) in a prospective, open label study in the intensive care unit of a cardiological clinic. We examined 49 episodes of monoAT in 38 patients (19 men/19 women). Thirty-three patients (87%) suffered from structural heart disease. Twenty-three episodes occurred while on antiarrhythmic therapy with class I or III drugs. Patients with prolonged QT interval (except for patients with pretreatment with class III drugs), hypokalemia, left ventricular failure, and recent myocardial infarction were excluded. All patients received one or two doses of 1 mg ibutilide fumarate under continuous rhythm monitoring. Conversion to sinus rhythm occurred in 19 episodes (38.8%), in 6 episodes (12.2%) after the first dose. Conversion rate was significantly higher in patients with a short history of symptoms (66.6% vs 28.6%; P < 0.05), of documented arrhythmia (0.13 (0/5.7) vs 2.6 (0.38/23.5) months, median (interquartile range); P < 0.03), higher atrial rate (272 +/- 49 vs 207 +/- 36 beats/min (means +/- SD); P < 0.004), or without preexisting antiarrhythmic therapy (53.8% vs 21.7%; P < 0.02). No differences in conversion rates were found regarding gender, age, body mass index, left ventricular function, left atrial diameter, or underlying disease. In three episodes torsade de pointes occurred after ibutilide (6.1%), requiring defibrillation in two cases (4.1%). Ibutilide can be used for conversion of monoAT with a similar efficacy as for atrial fibrillation, but with a considerably lower efficacy compared to typical atrial flutter.

Utility of adjunctive single oral bolus propafenone therapy in patients with atrial defibrillators

Previous studies have demonstrated that ambulatory atrial defibrillation shocks delivered by an implantable cardioverter-defibrillator (ICD) are safe and effective, but poorly tolerated. Separate studies have demonstrated the utility of single oral bolus propafenone for conversion of recent-onset atrial fibrillation (AF); however, most patients were hospitalized, had no structural heart disease, were taking no other antiarrhythmic drugs, and were not exposed to concomitant shock. We hypothesized that a single oral bolus dose of propafenone given early after onset would be a safe and effective adjunct to ICD-based AF therapy and improve overall therapy tolerance. A randomized three-way crossover study design was used to compare three strategies, deployed in the ambulatory setting early after AF episode onset in 35 ICD patients with advanced, drug refractory episodic/persistent syndromes, many of whom had structural heart disease and were taking other antiarrhythmic drugs: (i) single oral bolus propafenone (600 mg), followed by ICD shock if necessary; (ii) single oral bolus placebo, followed by ICD shock if necessary; and (iii) no oral bolus therapy and ICD shock if necessary (no bolus). Antiarrhythmic efficacy, defined by the restoration of sinus rhythm within 24 h, was similar during propafenone (81%) and no-bolus strategies (84%); both were significantly higher than during placebo strategy (62%). Propafenone was well tolerated and not associated with proarrhythmia. Shock use was significantly lower during propafenone strategy (19%) than during no-bolus strategy (55%); this was correlated with improved patient tolerance. Adjunctive use of single oral bolus propafenone is safe and effective in patients with an ICD and improves patient tolerance of device-based AF therapy.

Acute Conversion of Atrial Fibrillation in Two Dogs by Intravenous Amiodarone Administration

Journal of Veterinary Internal MedicineVolume 20, Issue 5 p. 1224-1227 Open Access Acute Conversion of Atrial Fibrillation in Two Dogs by Intravenous Amiodarone Administration Mark A. Oyama DVM, DACVIM-Cardiology, Mark A. Oyama DVM, DACVIM-Cardiology Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL. Department of Clinical Sciences, MJR-VHUP-Cardiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA. Department of Clinical Sciences, MJR-VHUP-Cardiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104; e-mail: [email protected]Search for more papers by this authorRobert Prosek, Robert Prosek Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL. Department of Small Animal Clinical Sciences, Veterinary Medical Center, University of Florida, Gainesville, FL.Search for more papers by this author Mark A. Oyama DVM, DACVIM-Cardiology, Mark A. Oyama DVM, DACVIM-Cardiology Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL. Department of Clinical Sciences, MJR-VHUP-Cardiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA. Department of Clinical Sciences, MJR-VHUP-Cardiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104; e-mail: [email protected]Search for more papers by this authorRobert Prosek, Robert Prosek Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL. Department of Small Animal Clinical Sciences, Veterinary Medical Center, University of Florida, Gainesville, FL.Search for more papers by this author First published: 05 February 2008 https://doi.org/10.1111/j.1939-1676.2006.tb00727.xCitations: 15 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL References 1 Fuster V., Ryden LE, Asinger RW, et al. ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation: Executive Summary. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines and Policy Conferences (Committee to Develop Guidelines for the Management of Patients with Atrial Fibrillation) Developed in Collaboration with the North American Society of Pacing and Electrophysiology. Circulation 2001; 104: 2118– 2150. 2 Nattel S., Shiroshita-Takeshita A., Brundel BJ, et al. Mechanisms of atrial fibrillation: Lessons from animal models. Prog Cardiovasc Dis 2005; 48: 9– 28. 3 Auer J., Weber T., Berent R., et al. Risk factors of postoperative atrial fibrillation after cardiac surgery. J Card Surg 2005; 20: 425– 431. 4 Martinez EA, Bass EB, Zimetbaum P. Pharmacologic control of rhythm: American College of Chest Physicians guidelines for the prevention and management of postoperative atrial fibrillation after cardiac surgery. Chest 2005; 128: 48S– 55S. 5 Slavik RS, Zed PJ. 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Lack of a hypotensive effect with rapid administration of a new aqueous formulation of intravenous amiodarone. Am J Cardiol 2004; 93: 576– 581. 11 Boriani G., Diemberger I., Biffi M., et al. Pharmacological cardioversion of atrial fibrillation: Current management and treatment options. Drugs 2004; 64: 2741– 2762. 12 Fransi S., Briedis J. Anaphylaxis to intravenous amiodarone. Anaesth Intens Care 2004; 32: 578– 579. 13 Stroke Prevention in Atrial Fibrillation Study, Final results. Circulation 1991; 84: 527– 539. 14 Stellbrink C., Schimpf T. Anticoagulation during cardioversion in patients with atrial fibrillation: Current clinical practice. Am J Cardiovasc Drugs 2005; 5: 155– 162. Citing Literature Volume20, Issue5September 2006Pages 1224-1227 ReferencesRelatedInformation

Bumpversion vs. thumpversion

A recent report of two cases of Finnovative_ restoration of sinus rhythm [1] is most interesting. The first patient who could terminate her own ventricular tachycardia by a sharp thump over her midsternum is a typical example of Fthumpversion_. The technique of a precordial thump for reverting ventricular tachycardia to sinus rhythm was first introduced by Pennington, Taylor and Lown in 1970 [2], hence the term Fthumpversion_ [3]. The second patient reported successful conversion of atrial fibrillation with rapid ventricular response when the