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Adenosine is commonly used for the chemical termination of supraventricular tachycardia. In addition, even when it is ineffective as an agent of chemical cardioversion, it may slow the cardiac rate to allow an analysis of the underlying rhythm. Common adverse effects include facial flushing, shortness of breath, and chest pain. Major contraindications include heart blocks and known adenosine hypersensitivity. This case report illustrates an episode of cardiopulmonary arrest after adenosine administration and, to the authors' knowledge, is the first occurrence reported in the literature.

Background: Flecainide for the treatment of supraventricular tachycardia (SVT) in newborns is still controversial because of its potentially severe proarrhythmic effects., Methods and Results: Between January 2004 and December 2006, we used flecainide to treat 20 consecutive newborns (15 males) with paroxysmal SVT without any structural heart disease. Their age at hospitalization was 11.5 +/- 11.1 days. The intravenous administration of flecainide (1 mg/kg) effectively restored sinus rhythm in all the patients. Once stable sinus rhythm had been restored, the drug was administered orally at a dose of 2 mg/kg/day twice daily, which was uptitrated as the patients gained weight. The patients were followed up for up to 24 months with clinical evaluations, baseline ECG and 24-h Holter monitoring every 3 months. There were neither deaths nor any episodes of heart failure or sustained ventricular tachycardia during follow-up. SVT were completely controlled in 17 patients (85%), with an oral dose of 3.35 +/- 1.35 mg/kg/day of flecainide; in the remaining three patients with refractory arrhythmias, propranolol was added for optimal treatment. No significant increase in the duration of QRS (70 +/- 1.09 vs. 63.8 +/- 1.87 ms, P = NS) or any significant QTc prolongation (413 +/- 7.4 vs. 412.6 +/- 8.01 ms, P = NS) was observed. One patient developed an incomplete right bundle branch block promptly reverted by reducing the dose., Conclusion: This preliminary experience indicates that flecainide is well tolerated and effective as first-line treatment for paroxysmal SVT in newborns without structural heart disease.

The purpose of this study was to examine the relationship between long-term efficacy of amiodarone therapy (100-200 mg/day) combined with angiotensin converting enzyme inhibitor (ACEI; enalapril 5 mg/day) administration, and the development of structural atrial remodeling in patients with paroxysmal atrial fibrillation (AF). Fifty-eight patients (40 men, 18 women, mean age, 68 +/- 8 years, mean follow-up period, 43 +/- 18 months) with AF refractory to >or= two class I antiarrhythmic drugs were divided into two groups; those treated with enalapril on amiodarone (group A, n = 25) and those treated with amiodarone alone (group B, n = 33), to evaluate the efficacy of combination therapy. 1) At 12 and 24 months, the survival rates for patients free from AF recurrence were 80% and 64% in group A, and 45% and 30% in group B, respectively (P < 0.05, group A versus group B). The percentage of patients with conversion to permanent AF despite amiodarone therapy was 20% in group A and 48.5% in group B (P < 0.05, group A versus group B). 2) In group B, left atrial dimension (LAD) was significantly greater after amiodarone therapy (40.2 +/- 6.3 mm) than at baseline (35.2 +/- 6.6 mm) (P < 0.01), whereas there was no significant difference in LAD between baseline and after amiodarone therapy in group A (39.1 +/- 5.0 mm versus 41.0 +/- 5.0 mm, respectively). In patients with paroxysmal AF, ACE-I appears to enhance the efficacy of amiodarone therapy in maintaining sinus rhythm and preventing the development of structural remodeling in atria.

Atrial fibrillation is commonly observed in patients with hypertrophic obstructive cardiomyopathy. Episodes of paroxysmal atrial fibrillation are often torturous and limit the quality of life by causing congestive heart failure, transient hypotension, or bradycardia. Control of paroxysmal atrial fibrillation in patients with hypertrophic obstructive cardiomyopathy is considered to be important for symptomatic improvement and prevention of the development to chronic atrial fibrillation. The authors report on 3 patients with hypertrophic obstructive cardiomyopathy who suffered from paroxysmal atrial fibrillation despite receiving medical treatment using antiarrhythmic agents. However, after undergoing percutaneous transluminal septal myocardial ablation, the incidence of episodes became significantly less frequent. Percutaneous transluminal septal myocardial ablation is normally performed for attenuating left ventricular obstruction by reducing the systolic anterior motion of the mitral leaflet. However, in these patients, this procedure was also effective in preventing supraventricular arrhythmia, probably by improving left ventricular diastolic dysfunction, smooth blood inflow into the left ventricular, and decreasing the pressure stress against the left atrial wall.

Aims: To investigate the clinical characteristics, management, and outcome of patients with paroxysmal atrial fibrillation (AF) associated with autonomic triggers., Methods and Results: One thousand five hundred and seventeen patients with paroxysmal AF participated in the Euro Heart Survey on AF. We categorized patients according to trigger pattern as reported by the physician: adrenergic (AF associated with exercise, emotion or during daytime only and absence of vagal triggers), vagal (postprandial or night time only, without presence of adrenergic triggers) and mixed (combination of vagal and adrenergic triggers). Vagal AF was found in 91 patients (6%), adrenergic in 229 patients (15%) and mixed in 175 (12%) patients. Underlying heart disease was equally prevalent in the three groups. Among patients with vagal AF, 73% were treated with non-recommended drugs according to the guidelines. In vagal AF, non-recommended treatment was associated with a shift to persistent or permanent AF in 19% of the patients, compared with none in the group receiving recommended treatment (P = 0.06)., Conclusion: This study is the first to address the issue of autonomic trigger patterns and AF in a large population. Autonomic trigger patterns were seen frequently in paroxysmal AF patients. Autonomic influences should be taken into consideration since non-recommended treatment may result in aggravation of vagal AF.

Amiodarone is well recognized as an anti-arrhythmic drug containing a high dose of iodine with considerable potential to cause thyroid dysfunction. The present patient was a 66-year-old Japanese woman who developed a cardiac arrhythmia and was given amiodarone as an anti-arrhythmic agent for approximately 3 months, until the day before her death. However, 19 days after starting amiodarone, serum testing indicated a hypothyroid status that was not recognized clinically. At autopsy, microscopy showed that most of the thyroid follicles were enlarged with dense colloid substance and lined by flattened follicular cells (involuted follicles). There were a small number of damaged follicles infiltrated by macrophages, which were immunopositive for HAM56. Sudan IV staining indicated many lipid droplets in follicular cells. Ultrastructurally the follicular cells contained large residual bodies composed of abundant electron-lucent lipid droplets of variable size. Although it is difficult to be certain of the direct link of amiodarone on the basis of a single case, it is reasonable to presume that this histopathology is associated with amiodarone-induced hypothyroidism and that involution changes represent the hypofunctional status of this drug-induced disorder. This is the first report on the histopathological findings of thyroid tissue from a patient with amiodarone-induced hypothyroidism.

Homeopathic Digitalis 6c was evaluated in two clinical cases of atrial paroxysmal tachycardia in dogs. Tachycardias are common cardiac problems in dogs, and atrial paroxysmal tachycardia is a serious cardiac arrhythmia that may lead to syncope. Both adult dogs (Labrador and German Shepherd) were treated with Digitalis 6c, 4 drops orally four times daily for 7 days. Following treatment with Digitalis 6c heart rate stabilised and synchronized atrial and ventricular electrical activity was restored in 7 days.

Omeprazole is a commonly prescribed inhibitor of the gastric proton pump and has numerous indications in the treatment of gastrointestinal diseases. It is primarily metabolized through the CYP2C19 enzyme, a member of the P450 mixed-function oxidase group, although a minor pathway of metabolism is through CYP3A4, another P450 enzyme. Digoxin is primarily metabolized outside the P450 system, but a minor pathway of metabolism is by CYP3A4. To our knowledge, this is the first known case of digoxin toxicity associated with omeprazole. The possible pathways for such an interaction are reviewed, including increased stomach absorption, p-glycoprotein activity and interactions in the P450 system.

Anticoagulation therapy in patients with atrial fibrillation is important. This review consists of three parts: chronic anticoagulation, anticoagulation for cardioversion, and a brief comment on anticoagulation around the time of left atrial radiofrequency ablation. The risk stratification scheme of the American College of Cardiology/American Heart Association/European Society of Cardiology (ACC/AHA/ESC) guidelines for chronic anticoagulation is briefly reviewed. Although there are several other similar schemes, they are not identical. The key point is the balance between benefit and risk. Some emerging controversies are outlined. Two specific questions explored are: is well-controlled hypertension a risk factor, and does paroxysmal atrial fibrillation confer the same risk as continuous atrial fibrillation? Differences in the risk of bleeding while taking a vitamin K antagonist noted in recent compared with older data are discussed. Risk of bleeding in the elderly and combined antithrombotic therapy with a vitamin K antagonist and an antiplatelet agent in high-risk patients are briefly discussed. Recent failures of studies attempting to find a suitable alternative to vitamin K antagonists are outlined. The treatment guidelines for anticoagulation for cardioversion are briefly reviewed. The risk of thromboembolism according to international normalized ratio and use of low-molecular-weight heparin as an alternative to warfarin are discussed. Anticoagulation before and after left atrial radiofrequency ablation is empirical, and long-term anticoagulation seems advisable for high risk patients at the present time. The two most pressing needs for further investigation are (1) clarification, simplification, and consolidated of risk stratification schemes and treatment recommendations and (2) discovery of alternatives to warfarin.

Noncompaction of the myocardium (NCM) is a rare congenital heart defect. It was first described 15 years ago, and few cases are published. The purpose of this study is to describe a NCM case. Clinical findings and imaging test results of a 37-year-old female patient with isolated NCM are presented. The patient complained of palpitations; her physical examination revealed extrasystoles, and her 12-lead electrocardiogram showed ventricular bigeminy. Three-dimensional Doppler echocardiography revealed numerous prominent trabeculations with deep intertrabecular recesses with blood flow which communicated with the ventricular cavity, which were more intense in the septal apical region. Cardiac magnetic resonance imaging corroborated the echocardiographic findings. The clinical presentation and the patients laboratory test results confirmed the diagnosis of isolated NCM. The knowledge of the echocardiographic findings of this disease enables an early diagnosis and a more adequate treatment.

The paper contains recommendations on treatment of supraventricular paroxysmal tachycardias (SVPT) during pregnancy. The recommendations are based on contemporary literature data and authors" own data. SVPT in postural syndrome are shown to be benign and to demand no continuous antiarrhythmic therapy, while tachycardiac attacks are terminated by vagal tests and adenosine application. Relapsing and steady forms of SVPT with a high heart rate are accompanied by subjective symptoms and require preventive antiarrhythmic therapy, which should be conducted considering risk/benefit ratio. According to the authors, sotalol is the most effective and safe pharmaceutical.

Background: Stepwise segmental pulmonary vein isolation (SPVI) and circumferential pulmonary vein isolation (CPVI) have been developed to treat patients with atrial fibrillation (AF), but the preferable approach for paroxysmal AF (PAF) has not been established., Methods and Results: One hundred and ten patients with symptomatic PAF were randomized into a stepwise SPVI group (n=55) or CPVI group (n=55). Systemic SPVI combined with left atrial linear ablation tailored by inducibility of AF was performed in the stepwise SPVI group. Circumferential linear ablation around the left and right-sided pulmonary veins (PVs) guided by 3-dimensional electroanatomic mapping was performed in the CPVI group. The endpoints of ablation are non-induciblity of AF in the stepwise SPVI group and continuity of circular lesions combined with PV isolation in the CPVI group. After the initial procedures, atrial tachyarrhythmis (ATa) recurred within the first 3 months in 23 of the 55 patients (41.8%) who underwent stepwise SPVI and in 20 of the 55 patients (36.4%) who had CPVI (p=0.69). Repeat procedures were performed in 7 patients from the stepwise SPVI group and 5 from the CPVI group (p=0.76). During the 3-9 months after the last procedure, 46 patients (83.6%) from the CPVI group and 43 (78.2%) from the stepwise SPVI group did not have symptomatic ATa while not taking anti-arrhythmic drugs (p=0.63). Severe subcutaneous hematoma or PV stenosis occurred in 3 patients., Conclusions: The efficacy of stepwise SPVI is comparable to that of CPVI for patients with PAF.

Azimilide hydrochloride (azimilide), an investigational antiarrhythmic drug, has shown variable efficacy in preventing atrial fibrillation (AF). This study was designed to assess its efficacy in maintaining sinus rhythm in patients with paroxysmal AF and heart disease. Patients with symptomatic paroxysmal AF were screened for 1 month by transtelephonic monitoring. After recording 1 episode of AF in the screening period, they were randomized to receive azimilide 125 mg or placebo once daily. Patients were stratified by the presence or absence of congestive heart failure or coronary heart disease (CHF/CHD). A maximum of 220 patients without CHF/CHD were randomized, with the remainder having CHF/CHD. Patients with CHF/CHD were monitored for 3 days during loading. The primary efficacy analysis was the time to the first symptomatic recurrence of AF in the CHF/CHD group. Secondary analyses were the time to the first recurrence in the entire population and the time to the first recurrence in those with significant structural heart disease. The median time to recurrence of AF in the CHF/CHD group was 10 days in the 2 treatment arms. Nonsignificant trends were seen toward efficacy of azimilide in the CHF/CHD group (hazard ratio 1.28, 95% confidence interval 0.97 to 1.70, p=0.087), structural heart disease group (hazard ratio 1.22, 95% confidence interval 0.96 to 1.56, p=0.11), and overall group (hazard ratio 1.22, 95% confidence interval 1.00 to 1.49, p=0.053). No patient died. In conclusion, azimilide showed a nonsignificant trend toward efficacy in maintaining sinus rhythm in patients with AF.

PSVT attack of >20min and frequency >160 is well-recognized model of myocardial dysfunction. We measured 6-keto-PGF1alpha and TXB(2) before and after adenosine administration to assess its cardioprotective potential. A total of 64 patients were randomly assigned as having acute episode of PSVT to adenosine or verapamil group. A bolus of 6mg of adenosine up to the maximum dose of 12 or 5mg of verapamil up to the maximum dose of 10mg were given, until the sinus rhythm was restored. The levels of PGI(2), TXA(2) and TAS were measured in three different time intervals. In adenosine group all parameters were normalized after 20min of conversion to sinus rhythm. The ratio of PGI(2)/TXA(2) increased after 5min of conversion to SR (P<0.01). Also, the ratio of TXA(2)/TAS was decreased for ADO (P<0.01). This is the first study to demonstrate that adenosine exerts cardioprotective effect.

Antiarrhythmic properties of taurhythman were demonstrated on experimental models of ventricular (early occlusion and calcium chloride-induced) and atrioventricular (aconitine-induced) arrhythmias. The preparation reduced or prevented episodes of paroxysmal tachycardia and ventricular fibrillation, decreased the incidence of arrhythmias, and increased the lethal dose (LD) of arrhythmogenic agents. By its efficiency, taurhythman was superior to procainamide and comparable to lidocaine.

Background: Atrial fibrillation is a progressive disease, which in the paroxysmal form (PAF) becomes more frequent and finally becomes chronic (CAF). A retrospective analysis of patients with PAF was conducted to examine the hypothesis that angiotensin-converting enzyme inhibitors (ACEI) will prevent the progression to CAF., Methods and Results: On the basis of their treatment, 95 patients with PAF were divided into 2 groups: 42 patients treated with ACEI for hypertension throughout the period of treatment and follow-up (ACEI group) and 53 patients not given ACEI (non-ACEI group). Cardiac rhythms were assessed either from the medical records or the electrocardiograms recorded every 2-4 weeks at follow-up visits. The mean follow-up time was 8.3+/-3.5 years. There was no significant difference in the use of antiarrhythmic drugs, left atrial diameter or left ventricular ejection fraction between the 2 groups. The Kaplan-Meier curve for the time to occurrence of CAF showed a lower incidence of CAF in the ACEI group and demonstrated that the 5-year probability for persistence of PAF without progression to CAF was 88.3%, but 47.5% in the non-ACEI group., Conclusions: These results indicate that ACEI will prevent progression from PAF to CAF.

Paroxysmal supraventricular tachycardias are often encountered in young and otherwise healthy patients. They are rarely life threatening even though they may alter the quality of life. In this article, we review the acute treatment of an episod of tachycardia and the prevention of recurrences.

Objectives: To examine trends in paramedic rhythm misidentification rates in the use of adenosine for presumed paroxysmal supraventricular tachycardia (PSVT) over a ten-year period, and to determine variables associated with rhythm misidentification., Methods: The authors conducted a retrospective analysis of all cases in which paramedics treated presumed PSVT with adenosine from 1993 to 2002. Rhythm strips were categorized as narrow or wide-complex and regular or irregular. Appropriate use of adenosine was defined as narrow-complex regular tachycardia with no visible P waves and rate greater than 140 beats/min., Results: The authors studied 224 patients with a mean age of 60 years (range, 15-94 years); 157 (70%) were female and predominantly white. The majority (54%) of patients had initial heart rates of 161-200 beats/min. Forty-nine percent of the patients had a previous history of PSVT. Inappropriate use of adenosine occurred in 45 (20%) cases. Misidentification rates per year ranged from 9% to 31% with the lowest rate occurring after a targeted education program on tachydysrhythmias. An initial heart rate of <160 beats/min (chi(2)=14.81, p<0.001) and absence of a medical history of either fast heart rate or palpitations (chi(2)=11.35, p=0.001) were associated with inappropriate use of adenosine., Conclusion: Paramedics in this emergency medical services system are more likely to use adenosine appropriately for patients with initial heart rates of >160 beats/min and a history of rapid heart rate or palpitations. Further studies are required to identify factors associated with rhythm interpretation errors in the prehospital setting as well as to evaluate error reduction strategies.

Atrioventricular reciprocating tachycardia (AVRT) using an accessory pathway is the most common supraventricular tachycardia observed in infancy and childhood. There is a general agreement to treat children older than 5 years who are on a potentially long-term antiarrhythmic agent with radiofrequency catheter ablation. Atenolol, a relatively long-acting and cardioselective beta-adrenoceptor blocker, has been used to control the various types of supraventricular tachycardia in children and adults. There are few reports on the use of atenolol in children <5 years old with AVRT. This retrospective study reports our experience in 22 children <5 years old (median age, 20 months) who received atenolol monotherapy between 1995 and 2001 for treatment of AVRT. AVRT was confirmed in 17 patients by transvenous or transesophageal electrophysiologic study and in 5 patients by documented preexcitation on electrocardiograms. In nine patients atenolol was the first antiarrhythmic drug given. In 15 of the 22 patients (68%) therapy with atenolol was considered successful. The average effective dose of atenolol in these 15 patients was 1.2 +/- 0.3 mg/kg/day. During a median follow-up of 41 months (8-74 months), atenolol had been discontinued in 10 patients and no further attacks of tachycardia occurred except in 1 patient. In no case did the drug have to be withdrawn for adverse effects. In conclusion, this retrospective study shows that atenolol as a monotherapy is efficient and relatively safe in the long-term treatment of AVRT in young children. Atenolol can be recommended as a first-line treatment option for the management of AVRT in infants and young children.

Objective: To compare the safety and efficacy of intravenous adenosine with verapamil in terminating acute episodes of paroxysmal supraventricular tachycardia., Methods: A randomized, multicenter trial to evaluate dose response in patients receiving adenosine and to compare the effects of adenosine with those of verapamil. A total of 122 patients with a tachycardia electrocardiographically consistent with paroxysmal supraventricular tachycardia were entered into the protocol. The adenosine group (n = 60) received sequential intravenous bolus doses of 3, 6, and 12 mg of adenosine to terminate PSVT and verapamil group (n = 62) were administrated 5mg or additional 5mg intravenously. Clinical variables and the time interval from the initiation of treatment to the termination of the supraventricular tachycardia, as well as the time from the initial effective dose of medication to the termination of supraventricular tachycardia were compared for adenosine and verapamil., Results: There was no significant difference between the two groups with respect to clinical variables. Relative drug efficacies were 86.0% (52/60) for adenosine versus 87.1% (54/62) for verapamil, P = NS. The average time after injection to termination of tachycardia by adenosine was shorter than that of verapamil significantly [(34.2 +/- 19.5) seconds vs. (414.4 +/- 191.2) seconds, P < 0.0001]. Adenosine caused adverse effects in 18.3% of patients, but they were transient and usually mild., Conclusions: Adenosine in graded doses up to 12 mg rapidly and effectively terminates acute episodes of paroxysmal supraventricular tachycardia. The overall efficacy of adenosine is similar to that of verapamil, but its onset of action is more rapid. Adverse reactions to adenosine are common but are minor and brief.

Our objective was to assess the efficacy of pharmacological treatment in reducing the incidence of permanent junctional reciprocating tachycardia in young children, or to bring the mean heart rate over 24 h to a normal level. We included 21 children with a median age of 0.05 year seen with permanent junctional reciprocating tachycardia over the period 1990 through 2001. Of these children, two had abnormal left ventricular function. Follow-up visits were made at least every 6 months. We registered the presence of the tachycardia over 24 h, the mean heart rate over 24 h, and cardiac function. Treatment was started with propafenone alone, or in combination with digoxin as the first choice. Treatment was effective in 14 cases (67%), with either complete disappearance of the tachycardia after discontinuation of medication, or continuation in sinus rhythm with medication; partially effective in 4 cases (20%) when the mean heart rate over 24 h on the last Holter recording was less than 1 standard deviation above the normal for age; but was not effective in the remaining 3 cases (14%). In 3 patients treated with propafenone, or 13 given propafenone and digoxin, treatment was effective in 12 (75%), partially effective in 2 (13%), and ineffective in the other 2 (13%). All 21 children had a normal left ventricular function at the end of follow-up. The median duration of follow-up was 2.4 years. Permanent junctional reciprocating tachycardia had disappeared spontaneously in one-third of the children, 5 being less than 1 year old. Adverse effects, seen in 5 cases, were mild or asymptomatic. No signs of proarrhythmia were registered. Pharmacological treatment, either with propafenone alone, or in combination with digoxin, is safe and effective in young children with permanent junctional reciprocating tachycardia. The mean heart rate is normalized, and cardiac function is restored and preserved. Radiofrequency ablation may be delayed to a safer age, with the arrhythmia disappearing spontaneously in one-third.

The paper describes one acute toxic hepatitis event in a woman of 60 with pleuropneumonia and exudative pleurisy. She had been treated with ethacizinum in small dose. To solve the problem, antioxidant and drug with hepato protective action should be prescribed along with ethacizinum.

Objectives: The aim of this study was to evaluate tecadenoson safety and efficacy during conversion of paroxysmal supraventricular tachycardia (PSVT) to sinus rhythm., Background: Tecadenoson (CVT-510), a novel adenosine receptor (Ado R) agonist, selectively activates the A1 Ado R and prolongs atrioventricular (AV) nodal conduction at doses lower than those required to cause A2 Ado R-mediated coronary and peripheral vasodilation. Unlike adenosine, which non-selectively activates all four Ado R subtypes and produces unwanted effects, tecadenoson appears to terminate AV node-dependent supraventricular tachycardias without hypotension and bronchoconstriction., Methods: In this open-label, multicenter, dose escalation study, tecadenoson was administered to 37 patients (AV node re-entrant tachycardia, n = 29; AV re-entrant tachycardia, n = 8) with inducible PSVT sustained for > or =1 min during an electrophysiology study. Seven regimens (0.3 to 15 microg/kg) of up to two identical tecadenoson intravenous bolus doses were administered., Results: After the first or second bolus, PSVT converted to sustained sinus rhythm for > or =5 min in 86.5% (32/37) of the patients, with 91% (29/32) of the conversions occurring after the first bolus (most within 30 s), coincident with anterograde conduction block in the AV node. No effects on sinus cycle length (SCL) or systolic blood pressure were observed. The atrial-His (AH), but not the His-ventricular (HV) interval was prolonged up to 5 min after the final tecadenoson bolus, returning to baseline by 10 min. Tecadenoson was generally well tolerated., Conclusions: In this study, tecadenoson rapidly terminated sustained PSVT by depressing AV nodal conduction without causing hypotension. After sinus rhythm restoration, there was minimal AH interval prolongation without HV interval or SCL prolongation.

Paroxysmal supraventricular tachycardia (PSVT) is a reentrant tachycardia, and the autonomic nervous system influences the paroxysms of PSVT. Tofisopam (Grandaxin) is a derivative of benzodiazepines. It is reported that heart rate variability (HRV) reveals the function of the autonomic nervous system and is used as an index of the effects of the autonomic nervous system on the heart rhythm. In previous studies, it was reported that tofisopam improved HRV. In this case report, the frequency of PSVT was significantly decreased and subjective symptoms of arrhythmia were eliminated after the administration of tofisopam. R-R interval variability and high-frequency power (HF; 0.15-0.40 Hz) were increased, and [low-frequency power (LF; 0.04-0.15 Hz)]/HF was decreased after administration of tofisopam. These results suggest that tofisopam overcame the existing imbalance of the sympathetic and vagus nervous system. In this case report, it is suggested that tofisopam is effective for the treatment of PSVT.

Cardiac rhabdomyoma, the most common cardiac tumor of infant and child, has been known to be associated with tuberous sclerosis complex. However, tuberous sclerosis complex with fetal supraventricular tachycardia is rarely reported. Herein, we report a female neonate diagnosed as tuberous sclerosis complex with cardiac rhabdomyoma presenting as supraventricular tachycardia. The newborn infant was initially treated with vagal maneuver, adenosine push, and digoxin. Although the tachycardia converted into normal sinus rhythm, frequent recurrence of PSVT was noted. At 16 days of age, the recurrent supraventricular tachycardia was refractory to vagal maneuver and drug therapy. Direct-current synchronized cardioversion converted the arrhythmia to normal sinus rhythm and oral digoxin effectively controlled the condition of the patient without further PSVT attacks. Subsequent 9-month follow-up revealed no further attack of arrhythmia. Regression of cardiac rhabdomyoma has not been visualized on echocardiogram at 9 months old.

Background: Prolongation of total filtered P wave duration (Ad) and low root mean square voltages for the last 20 ms of the P wave (LP20) on a P wave-triggered signal-averaged electrocardiogram (PSAECG) are typically observed in paroxysmal atrial fibrillation (PAF) patients. A shortening of atrial refractoriness and intra-atrial conduction delay (atrial remodeling) have been shown to occur in response to PAF. We, therefore, investigated the effects of spontaneous termination of PAF on the parameters of PSAECG., Methods: We measured the Ad, LP20 and left atrial (LA) diameter by ultrasonic echocardiography before, within 1 h after, and 3 and 12 months after PAF termination in patients with no structural heart disease (n=11)., Results: The PAF duration was 16+/-5 h. The Ads before, within 1 h after, and 3 and 12 months after PAF were 137+/-4, 148+/-4, 137+/-6, and 135+/-7 ms, respectively. The Ad within 1 h after PAF was significantly (P<0.01) longer than at the other three acquisition points. Although the LP20 within 1 h after PAF termination was not significantly different from the other three points, the change in LP20 (within 1 h after PAF-before PAF, -1.1+/-0.4 microV) in the long PAF duration group was significantly (P<0.05) greater than that of the short PAF duration group. LA diameter was unchanged at all points., Conclusion: These data suggest that PAF results in prolongation of Ad after termination of PAF.

Amiodarone is one of the most effective antiarrhythmic drugs available and is widely prescribed despite several potentially life-threatening side-effects. Hepatotoxicity is the most frequent one during long-term oral therapy: occasionally acute hepatitis necessitates the suspension of treatment but monitoring of a transient increase in serum aminotransferases is usually sufficient; the clinical-morphological pictures of liver cirrhosis have also been reported. Fulminant hepatitis soon after a parenteral load of the drug is far less well described in the literature. Most published cases were reversible after the suspension of treatment. A negative challenge after oral amiodarone exposure suggested that polysorbate 80, a solvent added to the intravenous infusion and already implied in the pathogenesis of a similar syndrome observed in infants, is a more likely cause of this complication. The occurrence of acute hepatitis complicating parenteral amiodarone treatment does not preclude subsequent oral use of the drug: an evidence-based therapeutic behavior now definitively consolidated. Because of the rarity of this diagnosis, we report 3 cases of short-term hepatotoxicity secondary to amiodarone treatment for supraventricular tachyarrhythmias: in 2 male patients with dilated cardiomyopathy and in a female with liver disease. The diagnosis was presumptive and based on a thorough drug history, the temporal relationship, the time-course of liver dysfunction, the exclusion of other causes and on the rapid improvement observed after parenteral amiodarone withdrawal in 2 cases; in no case could we find any other explanation for the liver damage. Since amiodarone is sometimes still an irreplaceable antiarrhythmic drug, we raise the question of whether careful and continuous vigilance should be mandatory in patients receiving the drug or whether it is possible to introduce a pharmaceutical preparation not containing the vehicle that induces acute liver toxicity.

Within 30 seconds after intravenous injection of somatostatin (sandostatin, 0.1 mg) we observed restoration of sinus rhythm in patients with atrioventricular (AV) junctional or orthodromic reciprocal tachycardias. This action was associated with interruption of re-entry on anterograde direction of AV conductivity. Somatostatin elicited pronounced cardiac electrophysiological effects which were due to activation of parasympathetic nervous system. Besides, it evoked transient elevation of systolic (+12.6%) and diastolic (+13.5%) blood pressures. High efficacy and good tolerance of somatostatin allow to consider this peptide as an alternative to adenosine and verapamil in the treatment of AV reciprocal tachycardias.

Background: Azimilide is a novel classification III antiarrhythmic agent that blocks both I(Kr)and I(Ks)and shows evidence of efficacy in patients with atrial fibrillation or flutter. Its effect on paroxysmal supraventricular tachycardia (PSVT) has not been reported., Methods and Results: One hundred ninety-three patients with symptomatic PSVT were enrolled in 4 double-blind, randomized, placebo-controlled clinical trials with almost identical trial design (supraventricular arrhythmia-1 [SVA-1], SVA-2, SVA-3, and SVA-4), performed as a separate stratum of studies that also included a stratum of patients with atrial fibrillation or flutter. Patients received oral azimilide (100 mg in SVA-1 and SVA-3, 35 or 75 mg in SVA-2, and 125 mg in SVA-4) or matching placebo twice daily for 3 days (loading period), followed by once-daily dosing (maintenance period). The primary outcome variable was the first recording of a symptomatic supraventricular arrhythmia (either PSVT, atrial fibrillation, or atrial flutter) recorded on a transtelephonic electrocardiographic event recorder. The duration of study was 270 days in SVA-1 and SVA-2 and 180 days in SVA-3 and SVA-4. Combined analysis results of the PSVT stratum from the 4 studies showed a dose-response relationship in prolongation of time to recurrence (P =.02). In the combined 100-mg daily dose, the hazard ratio (placebo:azimilide) was 2.35 (P =.023). The hazard ratio for the 125-mg daily dose measured 1.28 (P = not significant). However, the time to recurrence was prolonged when the patients receiving 100 and 125 mg daily were combined and compared with placebo (P =.02). There were no deaths and 1 case of torsades de pointes., Conclusion: These trial results suggest a significant dose-related suppression of PSVT with azimilide, with a low risk of serious adverse events.

A case is reported illustrating relationship between marked coronary atherosclerosis with development of painless myocardial ischemia (PMI) and constantly recurrent paroxysms of cardiac fibrillation (CF). A male 62-year-old patient suffering from paroxysmal CF received cordaron in a dose 200 mg twice a day. The treatment was ineffective until a comprehensive examination (thyroid hormones, echocardiography, Holter ECG monitoring, treadmill test, CT of the coronary arteries) found PMI episodes and severe stenosing atherosclerosis and the treatment was changed for sotalex (80 mg twice a day). Sotalex treatment was effective and stopped recurrences of CF.

Association of autonomic status and efficacy of therapy with amiodarone was studied in 90 patients with paroxysmal atrial fibrillation of ischemic (n=45, mean age 62 years) and nonischemic (n=45, mean age 38 years) origin. Autonomic status was assessed by measurement of heart rate variability. Electrophysiological and echocardiographical studies were also conducted before and after 4 weeks of amiodarone therapy. Treatment with amiodarone was accompanied by substantial lowering of the tone of autonomic nervous system in patients with adrenergic type of paroxysmal atrial fibrillation while there was no dynamics of parasympathetic tone in patients with vagal or mixed types. Positive association between amiodarone therapy and decrease of left atrial dimension and improvement of left ventricular contractility was also observed. It was concluded that the use of amiodarone was justified in adrenergic but not in vagal or mixed variants of paroxysmal atrial fibrillation.

Cross-over trial studied comparative effectiveness and tolerance of allapinine, rhythmonorm and isoptine in patients with paroxysmal supraventricular tachycardia (PSVT). Treatment effects did not differ much. Analysis of the preventive efficiency of the above drugs with reference to PSVT form has demonstrated that in paroxysmal atrioventricular reciprocal tachycardia the highest activity was shown by isoptine and rhythmonorm, in paroxysmal orthodromic reciprocal tachycardia--by rhythmonorm and allapinin. In long-term therapy, a preventive effects of allapinin, rhythmonorm and isoptine achieved at short-term course therapy persisted in 90.9, 95.6 and 81.5% patients, respectively. All the above drugs cause moderate inhibition of atrioventricular and intraventricular conduction. Isoptin had the best tolerance.

Objective: To determine whether the prehospital administration of adenosine to adults with stable and unstable paroxysmal supraventricular tachycardia (PSVT) influences conversion rate (CR) to sinus rhythm, scene time, use of synchronized electrical cardioversion (SEC), and accuracy of rhythm strip interpretation by paramedics., Methods: This before-and-after study compared a retrospective control group (CG) prior to the introduction of adenosine with a prospective treatment group (TG) following the addition of adenosine to the PSVT treatment protocol in a large urban advanced life support emergency medical services system. The population represented patients > or = 18 years of age with PSVT diagnosed by the paramedic (defined as spontaneous onset of a regular narrow-complex tachycardia between 140 and 250 beats/minute)., Results: The CG comprised 74 calls and the TG 137 calls. The overall CR was higher in the TG (59% vs 32%, p < 0.001). The SEC and spontaneous conversion rates remained unchanged. The proportion of untreated patients with PSVT decreased from 26% CG to 12% TG (p < 0.01). Scene times were longer in the TG (26 vs 19 minutes, p < 0.001). Agreement between paramedic and physician rhythm strip interpretations was fair to moderate (CG kappa 0.43 [95% CI: 0.14, 0.72]; TG kappa 0.37 [95% CI: 0.13, 0.61])., Conclusions: The introduction of adenosine was associated with a significant increase in the prehospital CR of stable and unstable PSVT, while the SEC and spontaneous conversion rates were similar in each group; however, scene times were longer in the TG and paramedic accuracy in rhythm strip interpretation remained fair to moderate.

Objectives: We investigated the clinical course of preterm infants with paroxysmal supraventricular tachycardia in comparison to their term counterparts., Background: Paroxysmal supraventricular tachycardia (PSVT) is the most common arrhythmia in childhood. It is known to cause significant morbidity and rarely mortality, most commonly in infants. Yet, there is minimal information in the literature on preterm infants with PSVT., Methods: Retrospective review of 40 infants, 26 term and 14 preterm, less than three months of age who presented with PSVT from January 1990 to January 1999. We compared the severity of first clinical presentation, in-hospital response to long-term medications, and outcome after discharge., Results: Symptomatic severity on presentation was not different between preterm and term infants. Preterm infants required fewer medication trials (p=0.01) and had no recurrences after discharge in contrast with 43 % recurrence in the term infants (p<0.0001). No preterm infants had Wolff-Parkinson-White syndrome (WPW) in contrast to 42 % of term infants (p=0.003). Term infants with WPW were more symptomatic (p=0.01), required more medications (p=0.004), but had a similar recurrence frequency as terms infants without WPW (p=0.95). Excluding infants with WPW, preterm infants were more severely symptomatic (p=0.02), yet no longer was there a difference in response to first medication trial (p=0.30)., Conclusions: We found that preterm infants with PSVT are as severely symptomatic on presentation, require fewer medications for adequate in-hospital control, and have fewer recurrences than their term counterparts. Unexpectedly, preterm infants did not present with WPW. The presence of WPW only in the term infants may account for differences in the clinical course between preterm and term infants.

Background: Drugs currently available for the acute treatment of paroxysmal atrial fibrillation have significant limitations. We assessed the safety and effectiveness of intravenous magnesium sulfate versus diltiazem therapy in patients with prolonged episodes of paroxysmal atrial fibrillation., Methods: In a prospective randomized trial, 46 symptomatic patients presenting with paroxysmal atrial fibrillation were given intravenous magnesium sulfate (n=23) or diltiazem (n=23) therapy. Primary outcome measures were effects on ventricular rate control and proportion of patients restored to sinus rhythm at 6 h after initiation of treatment., Results: There were no differences in baseline characteristics between the two groups. Both forms of treatment were well tolerated, with no adverse clinical events. Both drugs had similar efficacy in reducing the ventricular rate at the first hour of treatment (P<0.05) with a tendency toward a further decrease during infusion times of 2 (P<0.01), 3, 4, 5 and 6 h, respectively (P<0.001). However, at the end of the 6-h treatment period, restoration of sinus rhythm was observed in a significantly higher proportion of patients in the magnesium group compared with the diltiazem group [13 of 23 patients, (57%), versus five of 23 patients, (22%), P=0.03]., Conclusions: Magnesium sulfate favorably affects rate control and seems to promote the conversion of long lasting episodes of paroxysmal atrial fibrillation to sinus rhythm, representing a safe, reliable and cost-effective alternative treatment strategy to diltiazem.

We report a case of fetal Wolff-Parkinson-White (WPW) syndrome diagnosed prenatally by magnetocardiography (MCG). At 32 weeks' gestation, the fetus was diagnosed to have a paroxysmal supraventricular tachycardia by ultrasonography and direct fetal electrocardiogram (ECG). Transplacental fetal therapy by maternal oral administration of propranolol resolved the fetal tachyarrhythmia. Although the wave forms of the fetal MCG at 32 weeks' gestation were normal, the fetal MCG at 35 weeks' gestation showed a short PR interval and a long QRS complex duration with a delta wave, indicating WPW syndrome. The findings of the fetal MCG were confirmed by the postnatal ECG. MCG made the prenatal diagnosis of WPW syndrome possible., (Copyright 2001 S. Karger AG, Basel)

Background: The aim of this study was to identify, in children affected by permanent junctional reciprocating tachycardia (PJRT), the effective treatment., Methods: Seventeen children (9 males, 8 females, mean age 59 +/- 62 months, median 24) affected by PJRT were referred to our Institute between the years 1987 and 2000., Results: Pharmacological therapy was successfully used in 14 patients: flecainide and propranolol in 5 of them, amiodarone alone in 5 and associated with propranolol in 2, propafenone alone in 1 and in association with sotalol in 1. These drugs were given for a mean period of 54.5 +/- 49.8 months with resolution of the cardiomyopathy in 7/7 patients. Treatment had been continued for 3-6 months and there were no side effects. Nine patients were treated with radiofrequency transcatheter ablation, after 78 +/- 53.5 months of medical treatment, at a mean age of 150 +/- 16 months. The shortest endocardial ventriculo-atrial (VA) interval during tachycardia was recorded in all cases at the coronary sinus ostium (mean value of local VA-surface RP' interval -38 ms, range -24/-55 ms). Successful ablation of the anomalous pathway was obtained at this site in all patients (mean watts delivered 26 +/- 3 W, mean T degrees 64 +/- 5 degrees C). During the follow-up period (mean 21 +/- 17 months) 2 patients with recurrences of PJRT underwent a second successful procedure., Conclusions: PJRT in pediatric patients can be successfully treated with antiarrhythmic drugs, this may allow delay of the highly effective radiofrequency ablation treatment until the children have reached an adequate growth.

Background: Atrial fibrillation (AF), the most common form of sustained arrhythmia, is associated with a frightening risk of embolic complications, tachycardia-related ventricular dysfunction, and often disabling symptoms. Pharmacologic therapy is the treatment used most commonly to restore and maintain sinus rhythm, to prevent recurrences, or to control ventricular response rate., Methods: This article reviews published data on pharmacologic treatment and discusses alternative systems to classify AF and to choose appropriate pharmacologic therapy., Results: AF is either paroxysmal or chronic. Attacks of paroxysmal AF can differ in duration, frequency, and functional tolerance. In the new classification system described, 3 clinical aspects of paroxysmal AF are distinguished on the basis of their implications for therapy. Chronic AF usually occurs in association with clinical conditions that cause atrial distention. The risk of chronic AF is significantly increased by the presence of congestive heart failure or rheumatic heart disease. Mortality rate is greater among patients with chronic AF regardless of the presence of coexisting cardiac disease. The various options available for the treatment of chronic AF include restoration of sinus rhythm or control of ventricular rate. Cardioversion may be accomplished with pharmacologic or electrical treatment. For patients in whom cardioversion is not indicated or who have not responded to this therapy, antiarrhythmic agents used to control ventricular response rate include nondihydropyridine calcium antagonists, digoxin, or beta-blockers. For patients who are successfully cardioverted, sodium channel blockers or potassium channel blockers such as sotalol, amiodarone, or a pure class III agent such as dofetilide, a selective potassium channel blocker, may be used to prevent recurrent AF to maintain normal sinus rhythm., Conclusions: The ultimate choice of the antiarrhythmic drug will depend on the presence or absence of structural heart disease. An additional concern with chronic AF is the risk of arterial embolization resulting from atrial stasis and the formation of thrombi. In patients with chronic AF the risk of embolic stroke is increased 6-fold. Therefore anticoagulant therapy should be considered in patients at high risk for embolization. Selection of the appropriate treatment should be based on the concepts recently developed by the Sicilian Gambit Group (based on the specific channels blocked by the antiarrhythmic agent) and on clinical experience gained over the years with antiarrhythmic agents. For example, termination of AF is best accomplished with either a sodium channel blocker (class I agent) or a potassium channel blocker (class III agent). In contrast, ventricular response rate is readily controlled by a beta-blocker (propranolol) or a calcium channel blocker (verapamil). Alternatively, antiarrhythmic drug therapy may be chosen based on the Vaughan-Williams classification, which identifies the cellular electrophysiologic effects of the drug.

Objectives: We tested the efficacy of two drug treatments, flecainide (F) and the combination ofdiltiazem and propranolol (D/P), administered as a single oral dose for termination of the arrhythmic episodes., Background: Both prophylactic drug therapy and catheter ablation are questionable as first-line treatments in patients with infrequent and well-tolerated episodes of paroxysmal supraventricular tachycardia (SVT)., Methods: Among 42 eligible patients (13% of all screened for SVT) with infrequent (< or =5/year), well-tolerated and long-lasting episodes, 37 were enrolled and 33 had SVT inducible during electrophysiological study. In the latter, three treatments (placebo, F, and D/P) were administered in a random order 5 min after SVT induction on three different days., Results: Conversion to sinus rhythm occurred within 2 h in 52%, 61%, and 94% of patients on placebo, F and D/P, respectively (p < 0.001). The conversion time was shorter after D/P (32 +/- 22 min) than after placebo (77 +/- 42 min, p < 0.001) or F (74 +/- 37 min, p < 0.001). Four patients (1 placebo, 1 D/P, and 2 F) had hypotension and four (3 D/P and 1 F) a sinus rate <50 beats/min following SVT interruption. Patients were discharged on a single oral dose of the most effective drug treatment (F or D/P) at time of acute testing. Twenty-six patients were discharged on D/P and five on F. During 17 +/- 12 months follow-up, the treatment was successful in 81% of D/P patients and in 80% of F patients, as all the arrhythmic episodes were interrupted out-of-hospital within 2 h. In the remaining patients, a failure occurred during one or more episodes because of drug ineffectiveness or drug unavailability. One patient had syncope after D/P ingestion. During follow-up, the percentage of patients calling for emergency room assistance was significantly reduced as compared to the year before enrollment (9% vs. 100%, p < 0.0001)., Conclusions: The episodic treatment with oral D/P and F, as assessed during acute testing, appears effective in the management of selected patients with SVT. This therapeutic strategy minimizes the need for emergency room admissions during tachycardia recurrences.

Amiodarone is extensively used in cardiology practice because of its excellent antiarrhythmic properties. It produces alterations in thyroid functional because it contains 37% iodine and it is structurally similar to the thyroid hormones. Amiodarone inhibits 5'-deiodinase in the liver. The incidence of amiodarone-induced hyperthyroidism is between 6% and 12% of treated patients. The figures for pediatric patients are similar. Determination of tri-iodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH) plays an important role in the diagnosis and follow-up of thyroid alterations. Treatment options in amiodarone-induced hyperthyroidism in children include thionamide, potassium perchlorate, and prednisone. We present the case of hyperthyroidism secondary to amiodarone in a 10-year-old boy with Marfan's syndrome who was admitted several times for crises of paroxysmal supraventricular tachycardia and atrial fibrillation. After amiodarone treatment he presented a clinical and analytical picture of hyperthyroidism with very low TSH levels and increased free-T4 levels. Thyroid echography and scintigraphy were normal. Treatment with thiamazole did not alter the clinical picture, which returned to normal after prednisone administration. Currently, prednisone is being slowly withdrawn.Amiodarone. Hyperthyroidism. Antiarrhythmics.

The purpose of this study was to investigate the effect of the Valsalva maneuver on P-wave durations and dispersion. After the Valsalva maneuver, we found that maximum P-wave duration increased, minimum P-wave duration decreased, and P-wave dispersion increased in controls, whereas the opposite was true for unselected patients with paroxysmal AF. It was concluded that patients with paroxysmal AF performing the Valsalva maneuver normalized their P-wave dispersion, thereby correcting the inhomogeneous intra-atrial conduction.