Ventricular Flutter Research Articles

Prophylactic Implantable Defibrillator in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia and No Prior Ventricular Fibrillation or Sustained Ventricular Tachycardia

The role of implantable cardioverter-defibrillator (ICD) in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia and no prior ventricular fibrillation (VF) or sustained ventricular tachycardia is an unsolved issue. We studied 106 consecutive patients (62 men and 44 women; age, 35.6±18 years) with arrhythmogenic right ventricular cardiomyopathy/dysplasia who received an ICD based on 1 or more arrhythmic risk factors such as syncope, nonsustained ventricular tachycardia, familial sudden death, and inducibility at programmed ventricular stimulation. During follow-up of 58±35 months, 25 patients (24%) had appropriate ICD interventions and 17 (16%) had shocks for life-threatening VF or ventricular flutter. At 48 months, the actual survival rate was 100% compared with the VF/ventricular flutter-free survival rate of 77% (log-rank P=0.01). Syncope significantly predicted any appropriate ICD interventions (hazard ratio, 2.94; 95% confidence interval, 1.83 to 4.67; P=0.013) and shocks for VF/ventricular flutter (hazard ratio, 3.16; 95% confidence interval, 1.39 to 5.63; P=0.005). The positive predictive value of programmed ventricular stimulation was 35% for any appropriate ICD intervention and 20% for shocks for VF/ventricular flutter, with a negative predictive value of 70% and 74%. None of the 27 asymptomatic patients with isolated familial sudden death had appropriate ICD therapy. Twenty patients (19%) had inappropriate ICD interventions, and 18 (17%) had device-related complications. One fourth of patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia and no prior sustained ventricular tachycardia or VF had appropriate ICD interventions. Syncope was an important predictor of life-saving ICD intervention and is an indication for ICD. Prophylactic ICD may not be indicated in asymptomatic patients because of their low arrhythmic risk regardless of familial sudden death and programmed ventricular stimulation findings. Programmed ventricular stimulation had a low predictive accuracy for ICD therapy.

Synthetic ECG generation and Bayesian filtering using a Gaussian wave-based dynamical model

In this paper, we describe a Gaussian wave-based state space to model the temporal dynamics of electrocardiogram (ECG) signals. It is shown that this model may be effectively used for generating synthetic ECGs as well as separate characteristic waves (CWs) such as the atrial and ventricular complexes. The model uses separate state variables for each CW, i.e. P, QRS and T, and hence is capable of generating individual synthetic CWs as well as realistic ECG signals. The model is therefore useful for generating arrhythmias. Simulations of sinus bradycardia, sinus tachycardia, ventricular flutter, atrial fibrillation and ventricular tachycardia are presented. In addition, discrete versions of the equations are presented for a model-based Bayesian framework for denoising. This framework, together with an extended Kalman filter and extended Kalman smoother, was used for denoising the ECG for both normal rhythms and arrhythmias. For evaluating the denoising performance, the signal-to-noise ratio (SNR) improvement of the filter outputs and clinical parameter stability were studied. The results demonstrate superiority over a wide range of input SNRs, achieving a maximum 12.7 dB improvement. Results indicate that preventing clinically relevant distortion of the ECG is sensitive to the number of model parameters. Models are presented which do not exhibit such distortions. The approach presented in this paper may therefore serve as an effective framework for synthetic ECG generation and model-based filtering of noisy ECG recordings.

Vital bedrohliche brady- und tachykarde Herzrhythmusstörungen

Bradycardic (heart rate<50/min) and tachycardic heart rhythm disturbances (100/min) require rapid therapeutic strategies. Supraventricular tachycardias (SVT) are sinus tachycardia, atrial tachycardia, AV-nodal reentrant tachycardia and tachycardia due to accessory pathways. Mostly SVT are characterized by small QRS complexes (QRS width<0.12 ms). It is essential to evaluate the arrhythmia history, to perform a good physical examination and to exactly analyze the 12-lead electrocardiogram. An exact diagnosis is then possible in >90% of SVT patients. Ventricular tachycardias have a broad QRS complex (>or=0.12 s), ventricular flutter and ventricular fibrillation are associated with chaotic electrophysiologic findings. For acute therapy, we will present the new concept of the "5A" that includes adenosine, adrenaline, ajmaline, amiodarone and atropine. Additional "B, C and D strategies" include betablocking agents, cardioversion as well as defibrillation. The "5A" concept allows a safe and effective antiarrhythmic treatment of all bradycardic and tachycardic arrhythmias as well as asystolia.

Ventricular flutter in a child with Brugada syndrome

Brugada syndrome can cause syncope and sudden cardiac death from polymorphic ventricular tachycardia (VT) or ventricular fibrillation in individuals without structural heart disease. Although symptoms are commonest in the third and fourth decade of life, ventricular arrhythmias have also been reported in children. Fever is a well known trigger in patients with Brugada syndrome. 1 Kum L. Fung J. Sanderson J. Brugada syndrome unmasked by febrile illness. Pacing Clin Electrophysiol. 2002; 25: 1660-1661 Crossref PubMed Scopus (42) Google Scholar , 2 Skinner J.R. Chung S.K. Nel C.A. et al. Brugada syndrome masquerading as febrile seizures. Pediatrics. 2007; 119: e1206 Crossref PubMed Scopus (57) Google Scholar

Concept of the five 'A's for treating emergency arrhythmias.

Cardiac rhythm disturbances such as bradycardia (heart rate < 50/min) and tachycardia (heart rate > 100/min) require rapid therapeutic intervention. The supraventricular tachycardias (SVTs) are sinus tachycardia, atrial tachycardia, AV-nodal reentrant tachycardia, and tachycardia due to accessory pathways. All SVTs are characterized by a ventricular heart rate > 100/min and small QRS complexes (QRS width < 0.12 ms) during the tachycardia. It is essential to evaluate the arrhythmia history, to perform a good physical examination, and to accurately analyze the 12-lead electrocardiogram. A precise diagnosis of the SVT is then possible in more than 90% of patients. In ventricular tachycardia (VT) there are broad QRS complexes (QRS width > 0.12 s). Ventricular flutter and ventricular fibrillation are associated with chaotic electrophysiologic findings. For acute therapy, we will present the new concept of the five ‘A's, which refers to adenosine, adrenaline, ajmaline, amiodarone, and atropine. Additionally, there are the ‘B,’ ‘C,’ and ‘D’ strategies, which refer to beta-blockers, cardioversion, and defibrillation, respectively. The five ‘A’ concept allows a safe and effective antiarrhythmic treatment of all bradycardias, tachycardias, SVTs, VT, ventricular flutter, and ventricular fibrillation, as well as of asystole.

Emergency therapy of maternal and fetal arrhythmias during pregnancy

Atrial premature beats are frequently diagnosed during pregnancy (PR); supraventricular tachycardia (SVT) (atrial tachycardia, AV-nodal reentrant tachycardia, circus movement tachycardia) is less frequently diagnosed. For acute therapy, electrical cardioversion with 50–100 J is indicated in all unstable patients (pts). In stable SVT, the initial therapy includes vagal maneuvers to terminate tachycardias. For short-term management, when vagal maneuvers fail, intravenous adenosine is the first choice drug and may safely terminate the arrhythmia. Ventricular premature beats are also frequently present during PR and benign in most of the pts; however, malignant ventricular tachyarrhythmias (sustained ventricular tachycardia [VT], ventricular flutter [VFlut] or ventricular fibrillation [VF]) may occur. Electrical cardioversion is necessary in all pts who are in hemodynamically unstable situation with life-threatening ventricular tachyarrhythmias. In hemodynamically stable pts, initial therapy with ajmaline, procainamide or lidocaine is indicated. In pts with syncopal VT, VF, VFlut or aborted sudden death, an implantable cardioverter-defibrillator is indicated. In pts with symptomatic bradycardia, a pacemaker can be implanted using echocardiography at any stage of PR. The treatment of the pregnant patient with cardiac arrhythmias requires important modifications of the standard practice of arrhythmia management. The goal of therapy is to protect the patient and fetus through delivery, after which chronic or definitive therapy can be administered.

Does syncope require rhythmic and non-rhythmic evaluation in patients with previous MI?

BackgroundMultiple factors, in addition to left ventricular ejection fraction (LVEF) influence the risk of mortality in coronary artery disease. The purpose of this study was to evaluate the main causes...

034 Syncope after myocardial infarction. Changes of the results of programmed ventricular stimulation during the last 26 years

Ventricular tachycardia (VT) may explain syncope after myocardial infarction (MI) and is in this case is associated with a high risk of sudden death, mainly in association with low left ventricular ejection fraction (LVEF). Programmed ventricular stimulation (PVS) remains the main method to look for VT. The purpose of the study was to look for the changes of the population referred for PVS for unexplained syncope after MI during the last 26 years. 346 patients were recruited for unexplained syncope after MI between 1982 and 2008: 76 patients (group I) were studied between 1982 and 1989; 151 patients (group II) were studied between 1990 and 1999 and 119 patients (group III) were studied between 2000 and 2008. ECG and 24 hour Holter monitoring did not indicate a possible cause of syncope. LVEF was evaluated in all patients by echocardiography. PVS was systematic with the same protocol (up to 3 extrastimuli in 2 sites of right ventricle). Clinical and electrophysiological data were similar between groups I and II but differed significantly in group III: age was higher in group III (68±12 years) than in group I (64±11) and II (65±12) (p <0.009); LVEF was higher in group III (45±13%) than in group I (41±16) and II (42±13) (p<0.008). PVS was more frequently negative in group III (74%) than in group I (43%) and II (54%) (p<0.001). Monomorphic VT < 270 b/min was less frequently induced in group III (16%) than in group I (30%) and II (26%) (p<0.01). Ventricular flutter (VT > 270/min) and ventricular fibrillation were less frequently induced in group III (9%) than in group I (26%) and II (19%) (p<0.05).The changes could be related to the ICD implantation recommendations and to recanalization of occluded coronary artery, which is systematic in recent MI since 2000 (38% in group III, 27% in groups I and II) (p <0.05). Clinical data and results of PVS in patients admitted for unexplained syncope after MI infarction were identical between 1982 and 199 and have changed since 2000; patients are older and had relatively preserved LVEF. Therefore, the induction of a ventricular tachyarrhythmia is rarer than before the year 2000.

G008 Decrease of induction of ventricular flutter and fibrillation after myocardial infarction since primary angioplasty

Programmed ventricular stimulation (PVS) is used to stratify the arrhythmic risk after myocardial infarction (MI). Monomorphic ventricular tachycardia <270 b/min (VT) is associated with high risk, but induction of ventricular flutter or fibrillation (VF) has a discussed significance. Treatments have changed since the beginning of PVS. The purpose of the study was to look for the results of systematic PVS after MI between 1982 and 2008. PVS was performed in 780 patients without syncope or ventricular arrhythmias, between 1982 and 2008, from 4 to 8 weeks after acute MI: 301 (group I) were studied between 1982-1989; 315 (group II) between 1990-1999 and 164 (group III) between 2000-2008. PVS used the same protocol (up to 3 extrastimuli in 2 sites of right ventricle). Clinical and electrophysiological data were similar in groups I and II but differed in group III: age was higher in group III (61 ± 11 years) than in group I (56 ± 11) and II (58 ± 11) (p<0.002); left ventricular ejection fraction (LVEF) was lower in group III (36 ± 11 %) than in group I (44 ± 15), II (41 ± 12) (p < 0.05). PVS was as frequently negative in group III (58.5 %) than in group I (52 %), II (47 %). VT was induced as frequently in group III (26 %) than in group I (20 %), II (21.5 %). VF were less frequently induced in group III (15 %) than in group I (28.5 %) (p<0001) and II (29.5 %) (p<0.01). The changes were not related to beta blockers, similar in 3 groups (65 % in group I, 68 % in group II, 72 % in group III) or ACE inhibitors introduced in groups II (55 %), III (65 %). The changes could be related to primary angioplasty, systematic since 2000. Induction of ventricular flutter or fibrillation is actually rarer than in years 1985/2000. The decrease corresponded with the development of primary angioplasty and revascularization. The induction of monomorphic VT < 270 b/min has not changed although a lower LVEF in patients studied since 2000.

Cardiac Arrhythmias Classification Method Based on MUSIC, Morphological Descriptors, and Neural Network

An electrocardiogram (ECG) beat classification scheme based on multiple signal classification (MUSIC) algorithm, morphological descriptors, and neural networks is proposed for discriminating nine ECG beat types. These are normal, fusion of ventricular and normal, fusion of paced and normal, left bundle branch block, right bundle branch block, premature ventricular concentration, atrial premature contraction, paced beat, and ventricular flutter. ECG signal samples from MIT-BIH arrhythmia database are used to evaluate the scheme. MUSIC algorithm is used to calculate pseudospectrum of ECG signals. The low-frequency samples are picked to have the most valuable heartbeat information. These samples along with two morphological descriptors, which deliver the characteristics and features of all parts of the heart, form an input feature vector. This vector is used for the initial training of a classifier neural network. The neural network is designed to have nine sample outputs which constitute the nine beat types. Two neural network schemes, namely multilayered perceptron (MLP) neural network and a probabilistic neural network (PNN), are employed. The experimental results achieved a promising accuracy of 99.03% for classifying the beat types using MLP neural network. In addition, our scheme recognizes NORMAL class with 100% accuracy and never misclassifies any other classes as NORMAL.

Taser X26 Discharges in Swine: Ventricular Rhythm Capture is Dependent on Discharge Vector

Data from our previous studies indicate that Taser X26 stun devices can acutely alter cardiac function in swine. We hypothesized that most transcardiac discharge vectors would capture ventricular rhythm, but that other vectors, not traversing the heart, would fail to capture the ventricular rhythm. Using an Institutional Animal Care and Use Committee (IACUC) approved protocol, four Yorkshire pigs (25-36 kg) were anesthetized, paralyzed with succinylcholine (2 mg/kg), and then exposed to 10 second discharges from a police-issue Taser X26. For most discharges, the barbed darts were pushed manually into the skin to their full depth (12 mm) and were arranged in either transcardiac (such that a straight line connecting the darts would cross the region of the heart) or non-transcardiac vectors. A total of 11 different vectors and 22 discharge conditions were studied. For each vector, by simply rotating the cartridge 180-degrees in the gun, the primary current-emitting dart was changed and the direction of current flow during the discharge was reversed without physically moving the darts. Echocardiography and electrocardiograms (ECGs) were performed before, during, and after all discharges. p values < 0.05 were considered significant. ECGs were unreadable during the discharges because of electrical interference, but echocardiography images clearly demonstrated that ventricular rhythm was captured immediately in 52.5% (31 of 59) of the discharges on the ventral surface of the animal. In each of these cases, capture of the ventricular rhythm with rapid ventricular contractions consistent with ventricular tachycardia (VT) or flutter was seen throughout the discharge. A total of 27 discharges were administered with transcardiac vectors and ventricular capture occurred in 23 of these discharges (85.2% capture rate). A total of 32 non-transcardiac discharges were administered ventrally and capture was seen in only eight of these (25% capture rate). Ventricular fibrillation (VF) was seen with two vectors, both of which were transcardiac. In the remaining animals, VT occurred postdischarge until sinus rhythm was regained spontaneously. For most transcardiac vectors, Taser X26 caused immediate ventricular rhythm capture. This usually reverted spontaneously to sinus rhythm but potentially fatal VF was seen with two vectors. For some non-transcardiac vectors, capture was also seen but with a significantly (p < 0.0001) decreased incidence.

Cardiac contractility modulation in non-responders to cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) has become a standard therapy in cases of heart failure and asynchrony. Unfortunately, 20-30% of patients were non-responsive (NR) to CRT. In this report we used cardiac contractility modulation (CCM) as an adjunctive measure in NR patients. Sixteen NR patients, mean age 65 +/- 9 years, mean ejection fraction 27.3 +/- 7.4%, and New York Heart Association (NYHA) class III (n = 9) or IV (n = 7) despite CRT plus optimized medical therapy, received an additional CCM-implantation contra-lateral to the existing CRT system (OPTIMIZER III, Impulse Dynamics, Orangeburg, NY, USA). Cardiac contractility modulation delivers non-excitatory high-energy stimulatory impulses during the absolute refractory period, thus improving contractility [left ventricular (LV) dp/dt)] by stimulating the septum with two screw-in leads and one additional atrial lead for triggering the impulses. Acute LV dp/dt changes induced by CCM stimulation were measured by 5F Millar catheters placed in the LV during the implantation procedure in 14 of 16 cases. Patients were followed prospectively. Left ventricular dp/dt increased from a mean of 568 +/- 153 to 646 +/- 147 mmHg/s (+14%, P < 0.001) in the acute intraoperative testing. We noted the following complications and events during a follow-up of an average of 147 +/- 80 days (range 68-326) after CCM: intraoperative ventricular flutter needing cardioversion (n = 1), atrial lead dislocation (n = 1), coronary sinus (CS) lead dislocation (n = 1), painful stimulation requiring repositioning of septal leads (n = 1), true defibrillator shocks (n = 3), cardiac decompensations (n = 3), atrial fibrillation (n = 4), renal failure (n = 1), and pneumonia (n = 2). NYHA class improved from 3.4 to 2.8 (P < 0.01), and the ejection fraction increased from 27.3 +/- 5 to 31.1 +/- 6 (P < 0.01). Three patients (19%) died suddenly presumably due to electromechanical dissociation after 318, 104, and 81 days. No electrical interference was observed between the CCM and CRT systems, and in particular, at no time was the CRT-implantable cardioverter-defibrillator found to be delivering inadequate shocks. The CCM method is feasible and could be applied with calculated risks as a possible useful adjunct in CRT-NR when no other options are available; however, mortality and event rates are high in this very sick population.

Optimal programming of ICDs for prevention of appropriate and inappropriate shocks

Expansion of indications for implantable cardioverter-defibrillators (ICDs) has led to a significant increase in the number of patients receiving ICDs and the number of lives saved because of ICD therapy. However, appropriate or inappropriate shocks are frequent and may result in a significant decrease in quality of life in patients with ICDs. Atrial fibrillation with rapid ventricular response, sinus tachycardia, atrial tachycardia or atrial flutter with rapid conduction, and other supraventricular tachycardias are the most common arrhythmias causing inappropriate therapy. Other causes include oversensing of diaphragmatic potentials or myopotentials, T-wave oversensing, double or triple counting of intracardiac signals, lead fractures or header connection problems, lead chatter or noise, and electromagnetic interference. Strategies to reduce inappropriate therapy using device programming rely on the ability to distinguish supraventricular and atrial arrhythmias from ventricular tachycardia. Avoiding therapy for nonsustained ventricular arrhythmias and increasing the role of antitachycardia pacing to terminate ventricular tachycardia are key approaches to reducing shocks for ventricular arrhythmias. Optimal programming holds great promise for decreasing the overall incidence of shock therapy and increasing ICD acceptance.

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Synthesis and antiarrhythmic activity of n-(1-methyl-2-phenylethyl)aminoethanesulfonic acid isopropylamide hydrochloride

The synthesis and pharmacological properties of a new taurine amide derivative, N-(l-methyl-2-phenylethyl) aminoethanesulfonic acid isopropylamide hydrochloride (I), are described. Pronounced antiarrhythmic effect of compound I was observed in animals with experimental ventricular arrhythmias (early postocclusive and calcium chloride models). The drug significantly decreased the frequency and intensity of paroxysmal tachycardia attacks and ventricular fibrillation after coronary artery occlusion. Simultaneous administration of calcium chloride and compound I increased the arrhythmogenic dose of calcium chloride, inducing lethal heartbeat disorder and asystolia, and decreased the frequency of ventricular flutter and fibrillation. The antiarrhythmic effect of the drug was similar to that of lidocaine. The antifibrillatory activity is the most important manifestation of the antiarrhythmic action of the taurine derivative studied. These data suggest that compound I is a potential drug for urgent aid in myocardial infarction.

Sustained Polymorphic Arrhythmias Induced by Programmed Ventricular Stimulation have Prognostic Value in Patients Receiving Defibrillators

Patients with ischemic cardiomyopathy (ICM) who have monomorphic ventricular tachycardia (VT) induced by programmed ventricular stimulation (PVS) are at increased risk of sudden cardiac death (SCD). Among a primary prevention population, the prognostic significance of induced polymorphic ventricular arrhythmias is unknown. A total of 105 consecutive patients who received an implantable cardioverter-defibrillator (ICD) for primary prevention of SCD in the setting of ICM and non-sustained VT were retrospectively evaluated. Seventy-five patients (group I) had induction of monomorphic VT and 30 patients (group II) had a sustained ventricular arrhythmia other than monomorphic VT (ventricular flutter, ventricular fibrillation, and polymorphic VT) induced during PVS. Baseline characteristics were similar between group I and group II except for ejection fraction (25% vs. 31%, P = 0.0001) and QRS duration (123 milliseconds vs. 109 milliseconds, P = 0.04). Sixteen of 75 (21.3%) patients in group I and 6 of 30 (20%) patients in group II received appropriate ICD therapy (P = 0.88). Survival free from ICD therapy was similar between groups (P = 0.54). There was a trend toward increased all-cause mortality among patients in group I by Kaplan-Meier analysis (P = 0.08). However, when adjusted for age, EF, and QRS duration mortality was similar (P = 0.45). There is no difference in rates of appropriate ICD discharge or mortality between patients dichotomized by type of rhythm induced during PVS. These results suggest that patients in this population who have inducible VF or sustained polymorphic VT have similar rates of subsequent clinical ventricular tachyarrhythmias as those with inducible monomorphic VT.

Use of implantable cardioverter defibrillators in Canadian and US survivors of out-of-hospital cardiac arrest

Cardiac arrest due to ventricular arrhythmia in the absence of a reversible cause or contraindication has been a class I indication for insertion of an implantable cardioverter defibrillator since 1998. We compared and contrasted the use of implantable cardioverter defibrillator therapy in Canada and the United States among adults who survived a cardiac arrest. Data on hospital separations from April 1, 1994 through March 31, 2003 were obtained from the Health Person-Oriented Information Database maintained by Statistics Canada and from the US National Hospital Discharge Survey on all patients with a primary diagnosis of cardiac arrest, ventricular fibrillation or ventricular flutter for the same 9-year period. We excluded all records of patients with a secondary diagnosis of acute myocardial infarction. In Canada, 3793 patients survived to discharge after a cardiac arrest; 628 (16.6%) of these were implanted with a cardioverter defibrillator before discharge. The implant rate rose steadily from 5.4% in 1994/95 to 26.7% in 2002/03. In the United States, 23 688 (30.2%) of 78 538 such survivors received an implantable cardioverter defibrillator before discharge. Logistic regression analysis indicated that sex, age, fiscal year, the hospital's teaching status, hospital size and patient history of heart failure were positive predictors of implantable cardioverter defibrillator implantation. Age, renal failure, liver failure and cancer were negative predictors of receiving an implantable cardioverter defibrillator. The rate of use of implantable cardioverter defibrillator therapy for cardiac arrest survivors in Canada is increasing, but still is lower than the rate in the United States.

A proposed new theory for spontaneous ventricular fibrillation or flutter or ventricular premature contractions based on negative sequence voltages in patients with acute myocardial infarction

A proposed new theory for spontaneous ventricular fibrillation or flutter or ventricular premature contractions based on negative sequence voltages in patients with acute myocardial infarction

Akuttherapie lebensbedrohlicher tachykarder Rhythmusstörungen

Life-threatening supraventricular tachyarrhythmias include atrial fibrillation, atrial flutter, AV-nodal reentrant tachycardia with rapid ventricular response and preexcitation syndromes combined with atrial fibrillation. Ventricular tachyarrhythmias still remain one of the leading causes of death; these arrhythmias include monomorphic and polymorphic ventricular tachycardia, torsade de pointes tachycardia, ventricular fibrillation and ventricular flutter. In all patients with tachycardias, an attempt should be made to differentiate between narrow (QRS duration < 0.12 s) or wide QRS complex (QRS duration ≥ 0.12 s) tachycardias. In the assessment of patients (pts) with supraventricular/ventricular tachyarrhythmias, attention should be given to identify whether the tachycardia is associated with worsening angina or low cardiac output. In pts with narrow QRS complex tachycardias or pts with atrial fibrillation and preexcitation syndromes immediate synchronized cardioversion should be performed if signs or symptoms of instability (hypotension, evidence of end-organ dysfunction, worsening angina) exist. In pts with a stable hemodynamic situation, vagal maneuvers, adenosine or calcium channel blockers can be used. Management of atrial flutter usually centers on cardioversion or rapid atrial pacing to normal sinus rhythm. In the treatment of patients with deemed unstable ventricular tachycardia (VT), electrical cardioversion is the treatment of choice. In more stable patients, ajmaline is the preferred agent after myocardial infarction and lidocaine if myocardial ischemia is present. In pts with torsade de pointes tachycardias aggressive steps must be taken to prevent degeneration of this rhythm to ventricular fibrillation (VF). Magnesium sulfate has recently been demonstrated efficacious and is currently considered first-line drug therapy. Transcutaneous overdrive pacing should be attempted if magnesium is unsuccessful. The pt with pulseless VT or VF demands early electrical countershock.

Herzrhythmusstörungen bei Schwangeren

Maternal cardiac arrhythmias are frequently observed during pregnancy and they can range from benign, clinically-irrelevant isolated premature beats to debilitating supraventricular and ventricular tachycardia. However, malignant ventricular tachyarrhythmias, such as sustained ventricular tachycardia, ventricular flutter and ventricular fibrillation, are relatively rare particularly in women without the presence of an organic heart disease.