A case of lethal suicidal intoxication with propafenone and diazepam

Diazepam poisoning is a common emergency situation, but propafenone poisoning is relatively rare. We reported a case of propafenone poisoning combined with diazepam. An 18-year-old female patient was admitted to our hospital with an overdose of oral propafenone and diazepam. The patient was treated with medication that proved to be useful, but the sinus rhythm could not be recovered, and cardiac arrest occurred. A bipolar temporary pacemaker and extracorporeal membrane oxygenation (ECMO) were installed. However, even with multiple electrode positions, effective capture could not be achieved. The patient eventually died. We should be alert to the possibility of co-poisoning.

(N-NITROSO) PROPAFENONE INDUCED ADVANCED NODULAR MELANOMA-FIRST REPORTED CASE IN THE WORLD LITERATURE: THE INEXTRICABLE LINKS BETWEEN THE PHOTOCARCINOGENESIS, DRUG RELATED NITROSOGENESIS AND PHARMACO-ONCOGENESIS

Onco-pharmacogenesis or pharmaco-oncogenesis of skin cancer is a concept , which could also be considered as an "end product" of drug-mediated Nitrosogenesis or of the permissive regime for carcinogens to be (un)controlled released in drugs. Their controlled distribution remains until 2025 as a forced and non-alternative and there is no indication of any possibility to introduce a full elimination regime against the already mentioned carcinogenic availability. There are three main worrying facts that determine the need for these elimination regimes: 1) the clinicopathological correlations concerning the intake of a heterogeneous class of drugs and the subsequent development of relatively homogeneous tumours/ such as melanoma, 2) the recently proven mutagenic/ carcinogenic action of certain nitrosamines, but this time directly on human DNA, and 3) the fact that some of the nitrosamines are potent photocarcinogens that exert their genotoxic effects only after irradiation with UVA/ also recently proven/. In addition to the rhetoric mentioned above, there is also an overlap in mutational patterns between the genes previously generally accepted to affect melanomas - p53 / RAS oncogenes , with those identified as target genes, but being affected "mutationally", by certain nitrosamines. The processes of photocarcinogenesis, nitrosogenesis and oncopharmacogenesis of skin cancer are inextricably linked and should not be considered and analysed unilaterally or in a semi-invasive manner. Cataloguing the type of nitrosamines and their precise concentration on drug leaflets and prescription/official websites with permanent access to clinicians and end-users remains the only safe and effective weapon in the fight against (un)controlled contamination. The pharmaceutical industry and regulators remain the creators, the 'parents' of onco-pharmacogenesis, nitrosogenesis, and therefore the processes involved in the generation and progression of skin cancer. The impossibility of establishing elimination regimes for certain mutagens and/or carcinogens already proven to be present in medicines remains a mystery. In practice, end consumers find themselves in a state of enforced tolerance of certain genotoxic substances that are not even declared as available. Clinicians in the face of dermatologists/ dermatological surgeons remain the analysers and identifiers of these globalization processes. Once again, we present a patient who took the antiarrhythmic (nitroso-) drug propafenone and developed a relatively short-term nodular melanoma with a subsequent fatal outcome. We comment on the role of drug-mediated nitrosogenesis and its relationship to photocarcinogenesis and onco-pharmacogenesis.

Pharmacological cardioversion of atrial fibrillation: practical considerations

The choice between rhythm and rate control strategy represents one of the most intriguing dilemmas in the management of atrial fibrillation (AF). Although the advantage of rhythm over rate control in terms of outcome has not been unequivocally proven, the initial management of patients with symptomatic episodes of AF frequently involves early cardioversion. As electrical cardioversion (EC) is challenging in terms of fasting status and involvement of an anesthesiologic team, pharmacological cardioversion (PC) is usually selected as the first step toward rhythm conversion. Qualification criteria for PC or EC are similar and should comprise assessment of hemodynamic status, estimation of arrhythmic episode duration, evaluation of anticoagulation regimen, exclusion of other supraventricular arrhythmias, and assessment of the chance of rhythm conversion and persistence of sinus rhythm. Finally, the choice of adequate antiarrhythmic drug (AAD) depends on the presence of structural heart disease (SHD) and local experience. In patients without any SHD, complications occur rarely, hence traditional (propafenone, flecainide) or nonclassical Vaughan-Williams class I (antazoline) or class III (vernakalant, ibutilide, or dofetilide) drugs are preferred. The presence of SHD consistent with any left ventricular hypertrophy, heart failure, myocardial ischemia, or valvular heart disease limits the choice of AAD to amiodarone. Given the risk of ventricular proarrhythmia of AAD, safety should always prevail over the enticing possibility of rhythm conversion. The present review aims to provide a comprehensible summary of proper qualification for PC, selection of suitable AAD, and state‑of‑the‑art periprocedural management of patients with recent‑onset AF.

NITROSAMINE CONTAMINATION WITHIN CARDIAC MULTIMEDICATION - SARTANS (VALSARTAN), CALCIUM CHANNEL BLOCKERS (AMLODIPINE AND NIFEDIPINE), AND ANTIARRHYTHMICS (PROPAFENONE) AS A SIGNIFICANT FACTOR IN THE DEVELOPMENT AND PROGRESSION OF MULTIPLE KERATINOCYTIC CANCERS: ADVANCEMENT ROTATION FLAP FOR KERATOACANTHOMA OF THE UPPER LIP AND UNDERMINING SURGERY FOR BCC OF THE SHOULDER AS AN OPTIMAL DERMATOSURGICAL APPROACH

The data on the polycontamination of multimedication in polymorbid patients with a heterogeneous class of carcinogens/nitrosamines, NDSRIs (classified according to the FDA regulation to the companies of 2023 to those with a carcinogenic potency between 1 and 5), are one of the most important steps to clarify the concept of skin cancer nitrosogenesis/ pathogenesis. The FDA is the first regulatory institution in the world to courageously declare that a problem exists and should be addressed. The main and currently unexplained and somewhat controversial issue lies in 1) the sporadic nature of polycontamination in different geographical regions, and 2) the lack of official data from the established international, but also regional pharmaceutical market regulators on the results of the checks conducted for nitrosamine contamination of the respective batches. It is this that leads scientists to the idea of (albeit seemingly) speculative but entirely possible controlled contamination of the production in certain geographical regions. This (hypo)thesis is supported, albeit indirectly, by the fact that: a recent regional check for possible contamination of sartans in a particular geographical region was not indicative of the presence of any nitrosamines/NDSRIs. But this fact is indicative of several extremely important things: 1) contamination is not ubiquitous, its genesis is heterogeneous; 2) contamination could be completely avoided at production level in certain geographical regions; 3) ˝controlled contamination˝ or carelessness of a heterogeneous nature should be excluded by the relevant regulators. Regular inspection and certification of medicinal products in relevant geographical regions to exclude contamination with nitrosamines/NDSRIs would be the surest method to protect public health globally. The initial parameters of the restrictive processes for the availability of nitrosamines in medicines have been established by the most powerful regulator globally in the face of the FDA, with the hope being that manufacturers will find a short-term solution to the problem. We report another patient who simultaneously developed 2 cutaneous tumors under potentially/actually nitrosamine contaminated drugs such as: beta blockers- atenolol, calcium antagonists- nifedipine/amlodipine, sartans- valsartan and antiarrhythmics- propafenone. One of the tumors was localized in the upper lip area (keratoacanthoma) and the other in the right shoulder area (basal cell carcinoma). Successful surgical treatment of the tumors was performed in the form of upper lip advancement rotation flap and elliptical excision of the second lesion. The evolution/growth rate of the tumors in relation to the potential mutagens/carcinogens heterogeneous in their potency contained in the drugs is commented.

Formulation and stability of an extemporaneously compounded propafenone hydrochloride oral suspension for children with arrhythmia

OBJECTIVES

In children, supraventricular tachycardia is the most common form of arrhythmia, and propafenone is an effective class Ic antiarrhythmic agent used in this population. No suitable paediatric-specific, dosing-flexible preparation is available in Taiwan. The objective of this study was to develop a formulation of propafenone oral suspension prepared from commercially available propafenone tablets and commercially available oral syrup vehicles for related patients.

METHODS

An oral suspension of propafenone hydrochloride at a concentration of 10 mg/mL was prepared by mixing finely grounded propafenone hydrochloride tablets and a 1:1 mixture of Ora-Plus and Ora-Sweet. The beyond-use date was determined by analysing the samples stored at room temperature or 2-8℃ at time 0 and on days 7, 14, 21, 28, 35, 42, 56, and 90. Parameters to be inspected included appearance, pH measurement, high-performance liquid chromatography analysis, and microbial limit tests.

RESULTS

On the basis of the physicochemical and microbial stability results, the 10 mg/mL oral suspension of propafenone hydrochloride was stable at 2-8℃ and room temperature for at least 90 days. The suspension did not exhibit significant changes in drug concentration or pH level at any time point. Moreover, no apparent changes or microbial contaminations were observed for at least 90 days.

CONCLUSIONS

Propafenone hydrochloride in a 10 mg/mL oral suspension prepared by diluting fine powder with a 1:1 mixture of Ora-Plus and Ora-Sweet and stored in high-density polyethylene bottles and has a beyond-use date of 90 days when stored at 2-8℃ or room temperature. This finding enables us to improve the accuracy of dosage administration and reduce the risk of medication errors affecting the paediatric population.

COMBINED PHARMACOLOGICAL THERAPY INCLUDING SEVERAL ANTIARRHYTHMIC AGENTS FOR TREATMENT OF DIFFERENT DISORDERS OF CARDIAC RHYTHM

Combined therapy using several antiarrhythmic agents can be useful for treatment of different disorders of cardiac rhythm, including their hazardous and stable forms. It is especially required in case of insufficient efficacy after using one antiarrhythmic agent. As a combined therapy one can use the administration of several preparations e.g. 1) preparations of IA subclass and β-blocker adrenergic agents; 2) antiarrhythmic agents of I class and calcium channel blocker agents (verapamil and dilthiazem); 3) III class (amiodarone or sotalol) together with β-blocker drugs; 4) antiarrhythmic agents of III class and calcium antagonists; 5) antiarrhythmic agents of I and III classes. The latter combination has especially strong effect for treatment of arrhythmias caused by re-entry mechanism with or without a short excitability period. Antiarrhythmic agents of II class (β-blocker drugs) and III classes (amiodarone or sotalol) cause reduction of development risk of arrhythmias with trigger mechanism, including bidirectional spindle-shaped ventricular (torsade de pointes) tachycardia. Thus, combinations including preparations of II class together with III class and simultaneous using of antiarrhythmic agents of I and III classes should be administered to prevent hazardous potentially lethal arrhythmias. The authors of this article have developed a new method of combined therapy of paroxysmal supraventricular tachyarrhythmias in patients with ischemic heart disease, including the use of allapinin and cardiac glycosides. The author's certificate of invention was obtained for this method. The efficacy of this combined therapy for suppression of supraventricular paroxysmal tachyarrhythmias was analyzed compared to treatment with allapinin alone. It was proved that combined therapy has bigger effectiveness in comparison with therapy with help allapinin only. It is forbidden to use of such combinations of antiarrhythmic agents: β-adrenergic blocker agent + verapamil; β-adrenergic blocker agent + dilthizem; propafenone + verapamil; propafenone + dilthizem; propafenone + β-adrenergic blocker agent. After administration of such combined therapy, it is possible the occurrence medicinal (toxic) disfunction of sinus node. The administration of propafenone together with β-adrenergic blocker agent is impossible because propafenone has properties of β-blocker preparation. It is connected with similar chemical structure of propafenone and non-selective β-blocker agent propranolol.

[Current status of antiarrhythmic drug use and safety assessment in Chinese patients with atrial fibrillation]

Objective: To investigate the current status of antiarrhythmic drugs (AADs) use in Chinese patients with atrial fibrillation(AF) and assess the safety of AADs in this patient cohort. Methods: From January 2011 to December 2013, a total of 4 008 AF patients treated with AADs was enrolled in this study and patients were followed up for 24 months. Detailed information of prescribed drug, the causes of drug discontinuation and side effects were recorded. Results: Amiodarone was prescribed to 64.3%(2 579 cases) and propafenone to 31.1%(1 247 cases) of the enrolled patients, only 148 patients(3.7%) were treated with sotalol and 34 patients (0.8%) were treated with moracizine. The prevalence of heart failure (4.0%(102/2 579) vs. 1.4%(17/1 247, P<0.001), coronary heart disease (13.5% (348/2 579) vs. 7.4%(93/1 247), P<0.001) and non-ischemic cardiomyopathy (3.1%(78/2 579) vs. 0.7%(9/1 247), P<0.001) was significantly higher in patients treated with amiodarone than in the patients treated with propafenone. During the follow-up period, the discontinuation rate of amiodarone, propafenone, sotalol and moracizine was 28.8%(743/2 579), 25.1%(313/1 247), 14.2%(21/148) and 32.4%(11/34) respectively. The reasons of discontinuing amiodarone were: follow physicians' decision (75.7%, 563 cases), no effect (3.0%, 22 cases), side effects (4.3%, 32 cases) and patients' own decision (17.0%, 126 cases). The side effects of amiodarone included thyroid dysfunction (56.3%, 18 cases), bradycardia (12.5%, 4 cases), interstitial pneumonitis/pulmonary interstitial fibrosis (6.2%, 2 cases) and others (gastrointestinal symptom, rash, hepatic dysfunction, etc.). Conclusions: Amiodarone and propafenone are the most common AADs used in Chinese patients with atrial fibrillation. The prescription of AADs is essentially in accordance to the guideline of AF treatment. However, the discontinuation rates of AADs are high in Chinese AF patients. Lacking of better AADs is still a major problem in AF pharmacotherapy. Clinical Trial Registry Chinese Clinical Trial Registry, ChiCTR-OCH-13003729.

Brugada syndrome and right ventricle morphofunctional abnormalities on echocardiography in young male with family anamnesis of sudden cardiac death

First presented by Brugada and Brugada in 1992, Brugada Syndrome (BrS) is a primary electrical disease of the heart that causes sudden cardiac death or life-threatening ventricular arrhythmias. This disease is hereditary autosomic dominant transmitted and genetically determined. The syndrome has been linked to mutations in SCN5A, the gene encoding for the a-subunit of the sodium channel. Electrocardiogram (ECG) abnormalities indicating Brugada syndrome, include repolarization and depolarization abnormalities in the absence of identifiable structural cardiac abnormalities or other conditions or agents known to lead to ST-segment elevation in the right precordial leads (V1-V3). Intravenous administration of sodium channel blocking drugs may modify the ECG pattern. Ajmaline, flecainide, procainamide and propafenone exaggerate the ST-segment elevation or unmask it when it is initially absent. An implantable cardioverter-defibrillator (ICD) is the only proven effective device treatment for the disease. Although BrS is primary electrical disease, some authors have suggested the presence of morphological and functional abnormalities mainly located in the right ventricle (RV), notably in the outflow tract (RVOT). In this short report we will present a young male, with predisposition and positive family history of sudden cardiac death, with complete diagnostic procedure including propafenon testing unmasking Brugada syndrome. An echosonography revealed dilated apical right ventricle, suggesting BrS is not only electrical disorder, but may include morphofunctional abnormalities, described in previous reports. In addition, we reviewed the possible connection between Brugada syndrome and morphological abnormalities in RV.

Atrial fibrillation (acute onset)

INTRODUCTION

Acute atrial fibrillation is rapid, irregular, and chaotic atrial activity of less than 48 hours' duration. Risk factors for acute atrial fibrillation include increasing age, cardiovascular disease, alcohol, diabetes, and lung disease. Acute atrial fibrillation increases the risk of stroke and heart failure. The condition resolves spontaneously within 24 to 48 hours in over 50% of people; however, many people will require interventions to control heart rate or restore sinus rhythm.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent embolism, for conversion to sinus rhythm, and to control heart rate in people with recent-onset atrial fibrillation (within 7 days) who are haemodynamically stable? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 30 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: amiodarone, antithrombotic treatment before cardioversion, digoxin, diltiazem, direct current cardioversion, flecainide, propafenone, quinidine, sotalol, timolol, and verapamil.

[Ventricular preexcitation: is risk stratification feasible?]

The Wolff-Parkinson-White syndrome is a current debated clinical issue. Although the anatomical characteristics, polymorphic electrocardiographic features, and electrophysiological mechanisms of arrhythmias and sudden cardiac death are well known, the identification of patients at risk of sudden cardiac death remains challenging. Owing to the lack of effective therapeutic strategies, in the pre-ablation era many studies have been conducted to define the prognostic value of clinical and instrumental tests, and to define the actual risk of sudden cardiac death in patients with ventricular preexcitation. Nowadays, radiofrequency transcatheter ablation of anomalous atrioventricular pathways is a strong therapeutic option for all patients, independent of the risk of sudden cardiac death. However, radiofrequency ablation is associated with serious complications, but many studies confirm an overall good prognosis for most of the patients with electrocardiographic pattern of ventricular preexcitation. The aim of this review is to assess the prognostic value of clinical and instrumental tests in patients with ventricular preexcitation, referring to the latest knowledge.

Comparative investigation of the antiarrhythmic effect of propafenone (Rytmonorm) and lidocaine in patients with ventricular arrhythmias during acute myocardial infarction

Propafenone, a new class I antiarrhythmic drug, given as a bolus injection followed by oral medication, or lidocaine were given to 20 consecutive patients admitted with chest pain suggesting acute myocardial infarction and showing high grades, i.e. multiform, pairs or R-on-T premature ventricular complexes or short runs of ventricular tachycardia. Before institution of therapy the mean number (+/- 1 SD) of premature ventricular contractions (PVCs) per hour was 169 +/- 123 in the lidocaine group and 324 +/- 440 in the propafenone group. During the next 24 hours lidocaine reduced the numbers of PVCs by 73% and propafenone by 75%. The mean number (+/- 1 SD) of 5-minute periods with high grade PVCs was 4.3 +/- 2.9 in the lidocaine group and 5.8 +/- 4.5 in the propafenone group. During therapy this number was equally reduced in both groups to 2.4. One patient in the lidocaine group developed ventricular fibrillation and three patients in the propafenone group were excluded because of increasing numbers of PVCs. One patient in the propafenone group showed a torsade-de-pointes ventricular tachycardia.

Brugada syndrome, manifested by propafenone induced ST segment elevation

We report a case of a 43 year old man who was diagnosed with Brugada syndrome after propafenone administration for chemical cardioversion of new onset atrial fibrillation. Brugada syndrome has been described in the medical literature and is thought to be responsible for the majority of sudden cardiac deaths in patients without ischaemic heart disease. This syndrome has not yet been extensively discussed in the emergency medicine literature despite its importance. Emergency physicians should consider Brugada syndrome in patients who present to the emergency department with right bundle branch block and ST segment elevation in the right precordial leads, which is the classic electrocardiographic pattern of this syndrome.

Unmasking effect of propafenone on the concealed form of the Brugada phenomenon

A case report of a patient with frequent ventricular premature beats but with an otherwise normal ECG and no structural heart disease. Propafenone in therapeutical doses unmasked the ECG picture of the Brugada phenomenon.

Stress and pharmacologic tests as methods to identify patients with Wolff-Parkinson-White syndrome at risk of sudden death

Noninvasive stress and pharmacologic tests with procainamide and propafenone were studied as methods to identify patients with Wolff-Parkinson-White syndrome (WPW) who would otherwise be judged at risk of sudden death on the basis of electrophysiologic criteria: the shortest RR interval during induced atrial fibrillation less than or equal to 250 ms or accessory pathway anterograde effective refractory period less than or equal to 250 ms. Sixty-five patients were studied. Twenty-four patients fulfilled the electrophysiologic risk criteria (group A) and 41 patients fulfilled none of these criteria (group B). Persistence of preexcitation during stress test showed a sensitivity of 96% and a specificity of 17% to identify group A patients; its positive predictive value was 40% and negative predictive value 88%. With both procainamide and propafenone tests persistence of preexcitation identified group A patients with a sensitivity of 96% and a specificity of 51%; their positive and negative predictive value were, respectively, 53 and 95%. Stress and pharmacologic tests have good sensitivity and negative predictive value, but low specificity and positive predictive value.

Noninvasive serial electrophysiological testing using an implanted pacemaker for management of recurrent ventricular tachycardia

An implanted multiprogrammable pacemaker capable of performing both premature and burst stimulation can be teamed with a special external programmer for noninvasive electrophysiological testing. Such studies, combined with indications from provocative pharmacologic tests, allowed us to formulate effective antiarrhythmic therapies for three patients suffering from post-infarction, recurrent sustained ventricular tachycardia.

Myocardial uptake kinetics and pharmacodynamics of propafenone in the isolated perfused rabbit heart

The myocardial disposition of propafenone was studied in an isolated perfused rabbit heart. Six hearts were perfused with a modified Krebs-Henseleit buffer containing propafenone 110 +/- 5 ng/ml. Pharmacokinetic parameters were determined by fitting the coronary sinus effluent propafenone concentration-time data to a one-compartment pharmacokinetic model. The mean half-life of myocardial uptake (T1/2d) was 22.3 +/- 5.9 min and the average time to approach steady-state tissue levels was 112 +/- 29 min. Propafenone accumulated extensively in myocardium and at equilibrium the average (+/- S.D.) myocardial concentration was 114 +/- 21 times that of the perfusate. The electrophysiological effect was measured as percentage of change of the baseline QRS duration. The half-life of onset of effect (T1/2e) and the effect at steady state were determined by fitting the effect-time data to a monoexponential function. The T 1/2e averaged 26.0 +/- 9.4 min and did not differ significantly from T 1/2d. The relationship between myocardial propafenone concentration and effect was linear but there was interexperimental variability in the slopes of the lines of this concentration-effect relationship. The interexperimental differences in steady-state effect could not be accounted for by differences in myocardial concentration.

Effects of 17 beta-estradiol on the isolated rabbit heart

We have studied the effects of 17 beta-estradiol on the left ventricular pressure and on the coronary perfusion pressure in isolated rabbit heart, in order to evaluate the action of this hormone on the myocardial contractility and on the coronary resistances. 17 beta-Estradiol has induced a negative inotropic effect starting from a concentration of 10(-6) M and a vasodilation starting from 10(-7) M when administered on a vasopressin-induced coronary spasm. These effects are not related to sex or to alpha-, beta-adrenergic, histaminergic, anaesthetic-like mechanisms, but seem to interfere with calcium transport.

[Effects of propafenone on coronary and systemic hemodynamics]

This study was undertaken to evaluate the effects of intravenous Propafenone (2 mg/kg over 5') on Left Ventricular (LV) function and coronary blood flow. Twelve patients with coronary artery disease and post-ischemic LV disfunction were examined during routine cardiac catheterization. Serial measurements of central hemodynamics, LV high-fidelity pressure and coronary blood flow were recorded at rest and every 10' after Propafenone administration. Heart rate was unchanged, suggesting that Propafenone did not affect sympathetic tone. Cardiac index slightly decreased (from 3.3 +/- 0.9 L/min/m2 to 3.1 +/- 0.6 L/min/m2 at 10', p = ns), LV end-diastolic pressure rose significantly (from 17.7 +/- 2.1 mmHg to 22.7 +/- 4.2 mmHg at 20', p less than 0.01) and dP/dt max fell from 1897 +/- 291 mmHg/sec to 1577 +/- 312 mmHg/sec (p less than 0.02). Systemic vascular resistances had only minimal changes. Concomitantly, coronary vascular resistances decreased (from 0.77 +/- 0.17 mmHg/ml/min to 0.61 +/- 0.12 mmHg/ml/min, p less than 0.02) and coronary blood flow increased (from 138 +/- 29 ml/min to 172 +/- 21 ml/min, p less than 0.01). No significant difference was noted in myocardial oxygen consumption. No symptoms related to LV failure were observed during the study. In conclusion hemodynamic effects of Propafenone are characterized by moderate LV depression and by coronary artery dilatation, probably due to a calcium blocker-like activity.

[Electrophysiologic effects and clinical efficacy of propafenone in pediatric patients with paroxysmal supraventricular reentrant tachycardia]

Twenty patients (pts) with recurrent paroxysmal supraventricular tachycardia (PSVT), 12 female and 8 male, aged 9.8 +/- 4.7 years, underwent an electrophysiologic study (EPS) in order to assess the effects of propafenone (Pf) administered intravenously (1.5 mg/Kg in 3'). Thirteen pts (Group I) had an accessory pathway (AP) which was concealed in 5 and overt in 8 and in 12 of them an orthodromic atrioventricular reentrant tachycardia (ORT) was induced. In 5 of 7 pts (Group II) without AP an idio-nodal reentrant tachycardia (AVNRT) was induced. After Pf the sinus cycle length decreased significantly from 668 +/- 165 to 612 +/- 109 msec and PA, AH, HV intervals and QRS duration increased significantly from 35 +/- 11, 71 +/- 18, 34 +/- 6 and 73 +/- 12 to 43 +/- 11, 87 +/- 15, 39 +/- 9 and 85 +/- 10 msec respectively. The atrial and ventricular effective refractory period (ERP) increased from 216 +/- 18 and 211 +/- 19 to 227 +/- 21 and 217 +/- 21 msec respectively. The anterograde and retrograde nodal ERP and anterograde and retrograde Wenckebach point increased from 240 +/- 48, 227 +/- 28, 278 +/- 37 and 287 +/- 38 to 270 +/- 58, 330 +/- 32, 340 +/- 59 and 408 +/- 37 msec respectively. Pf terminated the tachycardia (T) in all 12 pts of Group I after prolongation of the cycle length which increased from 299 +/- 46 to 383 +/- 69 msec.(ABSTRACT TRUNCATED AT 250 WORDS)

Dynamic ECG evaluation of the acute oral test and short-term treatment]

The antiarrhythmic efficacy of Propafenone (PF) was evaluated in 24 patients with ventricular hyperkinetic arrhythmias by means of 24-hour Holter monitoring. The drug was administered as an acute bolus (450 mg) and, subsequently, in continuous therapy for 7 days at an average dose of 600 mg/day followed by a 5 days wash-out. The results of our study can be summarized as follows: High antiarrhythmic efficacy of the drug and good tolerability: 19 out of 24 patients showed, in continuous therapy, suppression of ventricular tachycardias (VT), reduction greater than or equal to 90% of couples, reduction greater than or equal to 70% of ventricular premature beats (VPBs). High predictivity value of the oral acute test with PF, (91.6%). Occurrence of first degree atrioventricular block in 4 patients (16.5%) and left bundle branch block in 3 patients (12.5%) with chronic treatment.

[Effect of propafenone on the pharmacokinetics of digoxin administered orally: a study in healthy volunteers]

It is well known that many cardiovascular drugs affect digoxin kinetics, but nothing is defined on propafenone-digoxin interaction. To clarify this problem, we studied digoxin kinetics in 8 healthy men, who received digoxin oral dose (0.50 mg) in the control state and again during maintenance therapy with propafenone (150 mg q.i.d.). Statistically significant changes were observed during propafenone in a number of digoxin kinetic indexes: a rise in peak serum digoxin concentration (4.30 vs 3.07 ng/ml - p less than 0.005), in area under the serum-digoxin concentration curve (4 h: 520.4 vs 368.9; 10 h: 789.6 vs 621.3 ng X min/ml - p less than 0.005; 24 h: 1187.6 vs 954.7 ng X min/ml - p less than 0.05) and urinary excretion of digoxin (277.7 vs 203.5 mcg - p less than 0.005). Renal digoxin clearance was not affected by propafenone. We conclude that propafenone interact kinetically with digoxin in healthy subjects, perhaps increasing digoxin bioavailability.

Apropos of 68 patients]

68 patients with rhythmical disorders unresponsive to treatment with one or several antiarrhythmics (quinidine derivatives 52 patients, amiodarone 28 patients, beta-blockers 24 patients) were treated by mouth with propafenone, with a mean postponement of 5.6 +/- 8.5 months (1 day to 33 months). Auricular arrhythmia was observed in 41 patients with the following results: 16 successes among the 24 patients with paroxysmal fibrillation of flutter, 3 successes among the 8 patients with an arrhythmia reduced by cardioversion, and 3 successes among the 9 patients with auricular tachycardia, including 6 systolic tachycardias. Of 8 patients with an intranodal reciprocal rhythm, 7 were treated successfully with propafenone, which acts on the retrograde part of the cycle. Successes were also recorded in 2 out of 3 patients with Wolff-Parkinson-White syndrome. In 19 cases of ventricular tachycardia, propafenone proved to be efficacious in 3 out of 5 cases presenting rapid discharges and in 7 out of 14 patients with continuous arrhythmias, notably those with a catecholaminergic component. Side-effects were digestive (5 patients), cardiac decompensation (3 patients), asthenia and asthma (1 patient) and the transformation of a flutter from 2/1 to 1/1 (1 patient).

3rd Comm.: Isolation of the conjugated metabolites in the dog and identification using fast atom bombardment mass spectrometry

The metabolism and urinary and biliary excretion of propafenone (2-(2'-hydroxy-3'-propylamino-propoxy)-omega-phenyl-propiophenone hydrochloride) were studied in the dog. Approximately 20% of the dose was excreted in 24 h with the urine and about 65% with the bile. Propafenone was extensively metabolized. Less than 4% of the dose was recovered unchanged in urine and bile. The metabolites were mainly excreted as conjugates. Free metabolites accounted for less than 20% of the dose. Separation methods were developed to isolate and purify the conjugated metabolites. Fractionation on an Al2O3-column yielded a sulphate and a glucuronide fraction, further separation and purification was done by TLC and HPLC. Positive and negative ion fast atom bombardment mass spectra (FAB/MS) were obtained of the purified glucuronides. The structures of two hydroxylated propafenone derivatives and two O-methylated catechol-like derivatives were definitely proven by FAB/MS, the glucuronic acid moiety being conjugated to the hydroxyl function in the different aromatic rings. Two isomeric propafenone glucuronides were found in the bile, probably diastereomeric forms of the O-glucuronide. Thus FAB/MS proved to be a complementary method to electron impact ionization mass spectrometry (EI/MS) for studying drug metabolism. The structures of free and conjugated metabolites can be defined from the combination of both mass spectrometric techniques.

Antiarrhythmic activity of 17 beta-aminoestratrienes. Comparison of 3-ols and 3-acetates with the corresponding 3-(3-amino-2-hydroxypropyl) ethers

The antiarrhythmic efficacy of 17 beta-amino- and 17 beta-amino-16 alpha-hydroxyestratrien-3-ols and 3-acetates (group 1) was compared with the efficacy of corresponding 3-[2-hydroxy-3-(isopropylamino)propyl] and 3-[2-hydroxy-3-(tert-butylamino)propyl] ethers (group II), substituents which are usually associated with beta-adrenoceptor blocking activity. Group I compounds exerted potent antiarrhythmic activity against both aconitine-induced arrhythmias in mice and ischemia-induced arrhythmias in rats and reduced the maximum following frequency of isolated guinea pig atria. Electrophysiological studies indicated that their mechanism of action is due to an ability to reduce the fast inward sodium current in cardiac cells (class I antiarrhythmic action). Group II compounds were inactive in the aconitine and atrial tests and electrophysiological studies confirmed that they were devoid of class I activity. However, these compounds, like both class I antiarrhythmic and beta-adrenoceptor blocking drugs, were active against ischemia-induced arrhythmias. Group II compounds, unlike group I compounds, exerted nonspecific beta-adrenoceptor blocking actions, which may account for their activity in the rat test. It was concluded that introduction of the 3-substituted ether group did not confer any advantage over the parent 3-ol or 3-acetate compounds.

Propafenone for the treatment of refractory complex ventricular ectopic activity

The results of therapy with propafenone were evaluated in 45 patients with complex ventricular ectopic activity that had been refractory to a mean of 3.8 antiarrhythmic drugs. The cardiac diagnoses were ischemic heart disease (in 16 patients), cardiomyopathy (in 7), mitral valve prolapse (in 7), mitral valve prolapse (in 7), idiopathic ventricular ectopic beats (in 6), valvular heart disease (in 5), and hypertension (in 4). The frequency of ventricular ectopic beats was established after therapy with antiarrhythmic agents had been discontinued. Patients then received propafenone during a dose-ranging protocol. An effective response was defined as a reduction in total ventricular ectopic beats of 80% or more. During dose ranging, therapy failed in four patients because of side effects, in eight because of a reduction in ventricular ectopic beats of less than 80%, and in three because of an aggravation of the arrhythmia. Thirty patients had a reduction in total ventricular ectopic beats of 80% or more. During a mean follow-up of 12.4 months, therapy failed in 1 patient because of sustained ventricular tachycardia and in 7 because of intolerable side effects; 22 patients continued to receive propafenone. PR and QRS intervals were significantly prolonged (P = 0.001), but the corrected QT interval and the heart rate were unchanged. The mean trough plasma level of propafenone associated with an effective response was 756 ng/ml, and that associated with intolerable side effects was 920 ng/ml. Thus, in patients with refractory complex ventricular ectopic beats, propafenone was effective and well tolerated initially in 67% of patients and during long-term administration in 49%, and toxicity was minor in most patients.

Electrophysiological effects of propafenone on isolated guinea-pig ventricular muscle and sheep Purkinje fibres

The electrophysiological effects of propafenone on transmembrane potentials were studied in sheep Purkinje fibres and guinea-pig ventricular muscle. In both preparations propafenone decreased the amplitude and Vmax of the action potential and shifted the resting membrane potential to less negative values. In Purkinje fibres, propafenone also slowed the conduction velocity and shortened the action potential duration whereas in ventricular muscle it had no effect on action potential duration. Propafenone also suppressed: the normal automatic mechanism in Purkinje fibres as well as the automaticity induced by BaCl2 and isoprenaline in ventricular muscle fibres with high resting membrane potential (between -75 mV and -85 mV), the abnormal automatic mechanisms, including the slow action potentials induced by BaCl2 and isoprenaline in ventricular muscle and Purkinje fibres depolarized above -55 mV, respectively, and the delayed after-depolarizations induced by ouabain in Purkinje fibres and ventricular muscle. The possible mechanisms responsible for the cardiac effects of propafenone and the therapeutic implications of these electrophysiological effects are discussed.

Electrophysiological effects of propafenone in untreated and propafenone-pretreated guinea-pig atrial and ventricular muscle fibres

The electrophysiological effects of propafenone (10(-7) to 10(-4) M) were studied on guinea-pig isolated atrial and ventricular muscle fibres obtained from untreated animals and animals pretreated with propafenone, 3 and 10 mg kg-1, for 28 days. In untreated atria propafenone produced a dose-dependent decrease in the rate and maximum following frequency, prolonged the sinus node recovery time and reduced the maximum chronotropic responses to isoprenaline. In untreated atrial and ventricular muscle fibres propafenone depressed action potential amplitude and Vmax, reduced the resting membrane potential and prolonged the action potential duration (APD) and the effective refractory period, lengthening the effective refractory period relative to APD. Propafenone depressed the amplitude and Vmax and shortened the duration of the slow action potentials induced by isoprenaline and caffeine in K-depolarized papillary muscles. Pretreatment with propafenone reduced atrial rate, but did not modify the action potential characteristics compared to the values obtained in untreated atria. Further addition of propafenone produced similar but more marked changes in untreated atria. In ventricular muscle fibres pretreated with 3 mg kg-1, action potential characteristics before and after further addition of propafenone were similar to those obtained in untreated fibres. However, muscles pretreated with 10 mg kg-1 exhibited a significant prolongation of the APD compared to that in untreated muscles or those pretreated with 3 mg kg-1; further addition of propafenone shortened the APD even when this parameter was of similar value to those observed in the other two series of experiments. It is concluded that even though the effects of propafenone are similar to those of quinidine (class I antiarrhythmic), it also exhibited class II and class IV actions. In pretreated animals a prolongation of the APD (class III action) could also be involved in the antiarrhythmic effects of the drug.

The yield of programmed ventricular stimulation in mitral valve prolapse patients with ventricular arrhythmias

A high-risk subset of patients with mitral valve prolapse (MVP) and a predisposition to sudden cardiac death (SCD) has been proposed. We analyzed the results of programmed ventricular stimulation (PVS) in 20 patients with MVP and ventricular arrhythmias (ventricular premature depolarization in 6, ventricular couplets in 2, nonsustained ventricular tachycardia [VT] in 7, ventricular fibrillation [VF] in 5) and in 12 "normal" control subjects. With the use of an identical stimulation protocol from the right ventricular apex (twice diastolic threshold, three extrastimuli), 9 of 20 MVP patients and 1 of 12 normal subjects had inducible ventricular arrhythmias (p less than 0.05). When more aggressive attempts at ventricular stimulation were used, an additional five MVP patients had positive responses to PVS while no normal subjects did. In the MVP group, the following arrhythmias were induced: nonsustained polymorphic VT in 10, VF in three, and ventricular flutter in one. In all but two patients, triple ventricular extrastimuli were required to elicit this response. Two of the 10 MVP patients undergoing electropharmacologic testing had a successful antiarrhythmic regimen identified, while 13 patients were discharged on empiric antiarrhythmic therapy. At a follow-up of 19.8 +/- 13.1 months, all 19 MVP patients who could be contacted were alive. Five patients had symptomatic recurrences at follow-up including two SCD survivors (VT in one and VF in one). In conclusion, it was found that the majority of MVP patients with ventricular arrhythmias have inducible ventricular tachyarrhythmias during PVS and are more susceptible to this than patients without structural heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Propafenone therapy for ventricular tachycardia in the setting of congestive heart failure

The combined occurrence of impaired left ventricular function and ventricular tachyarrhythmias portend a high annual mortality. Although antiarrhythmic drugs can reduce ventricular arrhythmias, the prognosis may be unchanged. We administered propafenone to 12 patients with ventricular tachyarrhythmias and left ventricular ejection fractions less than 40%. Propafenone significantly reduced isolated ventricular premature depolarizations, couplets, and ventricular tachycardia on ambulatory monitoring. Propafenone eliminated all exercise provocable ventricular tachycardia. Propafenone additionally abolished ventricular tachycardia inducible by programmed stimulation in five of six patients. In eight patients studied before and during therapy, there was no significant change in left ventricular ejection fraction determined by nuclear ventriculography. Propafenone was discontinued in three patients due to side effects. All patients remain alive and without recurrence of clinically significant arrhythmia over a mean follow-up period of 14 months. Propafenone is an effective drug for the management of ventricular tachyarrhythmias, and may be used in patients with impaired left ventricular function.

Usefulness of programmed stimulation in predicting efficacy of propafenone in long-term antiarrhythmic therapy for paroxysmal supraventricular tachycardia

The electrophysiologic effects of intravenous (i.v.) and oral propafenone were evaluated in 14 patients with Wolff-Parkinson-White syndrome and in 10 patients with atrioventricular (AV) nodal reentrant tachycardia. The effective refractory periods of the right atrium and the AV node increased after both preparations. In patients with Wolff-Parkinson-White syndrome, i.v. propafenone blocked anterograde accessory pathway conduction in 2 patients and retrograde conduction in 1; during oral therapy, accessory pathway conduction block occurred in 2 additional patients. The mean cycle length of the supraventricular tachycardia (SVT) increased from 338 +/- 60 ms to 387 +/- 56 ms (p less than 0.05) after i.v. application, and from 336 +/- 65 ms to 367 +/- 65 ms (p less than 0.05) during oral propafenone. The shortest pacing interval maintaining a 1:1 AV conduction increased from 325 +/- 65 ms to 368 +/- 81 ms (p less than 0.05) after i.v. infusion, and from 333 +/- 57 ms to 369 +/- 75 ms (p less than 0.05) during oral therapy. There was no difference in the electrophysiologic effects between i.v. and oral propafenone. The induction of SVT was prevented by i.v. propafenone in 10 of 20 patients and in 4 additional patients with oral propafenone. During follow-up, 6 of 7 patients, whose SVT could not be initiated by electrophysiologic drug testing, remained free from recurrences, whereas 5 of 7 patients with inducible tachycardia had recurrences of SVT. Thus, in patients with SVT, propafenone prolonged accessory pathway and AV nodal conduction and had a beneficial effect on circus movement tachycardia.(ABSTRACT TRUNCATED AT 250 WORDS)

[Treatment of recurrent ventricular tachycardias using oral propafenone]

The effect of oral propafenone on prevention of pacing-induced ventricular tachycardia (VT) was studied in 11 patients. All patients experienced documented sustained VT refractory to 4.1 +/- 2 antiarrhythmic agents per patient including amiodarone in 8. Programmed electrical stimulation was performed before and 48-72 hours after oral propafenone (900 mg/day) 2-3 hours after the last dose. Two patients developed spontaneous incessant VT before the scheduled date of the study on propafenone, and were classified as aggravation. Propafenone prevented pacing-induced VT in 2 patients (successful results). In 3 additional patients the results were partial, as non-sustained VT was induced on propafenone whereas sustained VT could be provoked during the control study. In the remaining 4 patients, oral propafenone failed to prevent pacing-induced VT. Tachycardia cycle length increased in 3 (C = 284 +/- 129 P = 450 +/- 202 ms) and was shorter in 1 aggravation. The 5 patients with successful or partial results (45.4 p. cent), underwent long-term therapy with a mean follow up of 5.6 +/- 4 months. Recurrence of VT occurred in 2. The remaining 3 are well controlled. This study demonstrates that propafenone is able to prevent pacing-induced VT in a limited number of patients. Stimulation techniques are useful in order to detect patients with potential pro-arrhythmic effect.

Pharmacokinetics of intravenous propafenone in patients with episodes of paroxysmal supraventricular tachycardia

The plasma concentration time curves of propafenone after administration of single i.v. (2.3 +/- 0.2 mg/kg) doses have been studied in ten patients undergoing an electrophysiological study to evaluate episodes of recurrent supraventricular tachycardia. The propafenone kinetics profile can be described by a two-compartment open model. Mean values of main variables were t 1/2 alpha = 2.8 min, t 1/2 beta = 80 min, Kel = 0.12 min, -1, Vd beta = 1.6 1/kg, Cl = 1.03 1/h and AUR = 3.1 mg/h-1.

Aggravation of electrically provoked ventricular tachycardia during treatment with propafenone

Propafenone is a new class Ic antiarrhythmic agent currently being investigated in the United States. It is generally well tolerated. We administered propafenone to 16 patients with ventricular tachycardia (VT) that had been refractory to conventional antiarrhythmic drug therapy. Three of these 16 patients developed electrically provoked incessant VT during treatment with propafenone without other evidence of toxicity. These arrhythmias subsided after lidocaine was administered. Propafenone therapy was discontinued in each case. Incessant VT did not develop in any of these patients in the absence of antiarrhythmic drugs or on antiarrhythmic drugs other than propafenone. Alternative effective treatment was identified for each patient. Although VT was initially provoked by pacing in each of these patients, these observations suggest that propafenone, like some other class Ic drugs, may favor the development of incessant VT in occasional patients. This appears most likely to occur in patients with ventricular dysfunction and prior sustained VT or ventricular fibrillation.

[Oral propafenone in resistant auricular arrhythmia]

Paroxysmal episodes of atrial frequently cause severe functional disturbance because of their recurrent nature. Propafenone (Rythmol) is a very active anti-arrhythmic at the ventricular level which acts by decreasing the rate of atrio-ventricular and intra-ventricular conduction and by prolonging the refractory period of the right atrium and the accessory pathways. The authors conducted an open study of this drug in 20 cases with resistant, recurrent atrial fibrillation. All of the patients were known to have recurrent episodes of atrial fibrillation which could not be prevented by a variety of antiarrhythmic agents. They performed a clinical, electrocardiological and laboratory evaluation of these patients. Holter monitor recordings were performed prior to entry into the study, during the first week of treatment, between the 4th day and the 8th day, on the 20th day, at the 2nd month and between the 3rd and 6th months. Propafenone was prescribed at a dose of 900 mg per day and the initial dose was reduced to 600 mg after the 3rd month of treatment. Five patients can be classified as therapeutic failures, as the arrhythmia recurred. These patients presented a "vagal" atrial fibrillation preceded by an episode of bradycardia. 15 patients can be considered to have obtained a successful result, as no recurrences were detected during the 6 month observation period. The electrical and laboratory tolerance was satisfactory. The most frequent side effects were minor transient gastrointestinal disturbances.