Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EXTRASYSTOLE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed1990

Post-extrasystolic potentiation without a compensatory pause in normal and diseased hearts.

Variables derived from left ventricular volume were used to study post-extrasystolic potentiation. Left ventriculograms were obtained from 11 healthy individuals and 49 patients with coronary heart disease (30 with a previous myocardial infarction and 19 without any signs of myocardial damage). Post-extrasystolic potentiation was induced by a regularly driven right atrial rhythm that was interrupted by one atrial extrasystole in such a way that the post-extrasystolic RR interval was kept equal to the basic RR interval. The left ventricular end diastolic volumes of the pre-extrasystolic and post-extrasystolic beats were equal. In all groups there was evidence of post-extrasystolic potentiation in one or more of the indices of left ventricular function (ejection fraction, mean normalised systolic ejection rate, and systolic volume, and stroke volume). Potentiation was especially evident in patients with left ventricular damage; this suggests that a compensating mechanism is an intrinsic property of the myocardium. The Frank-Starling mechanism does not contribute to the increased performance of the post-extrasystolic beat in normal individuals or in patients with coronary artery disease.

Action Potentials↗
PubMed1980

QRS waveform of ventricular extrasystoles and their differentiation from aberrant conduction.

Horizontal and frontal plane QRS loops of patients in sinus rhythm with uniform ventricular extrasystoles were constructed from digitised Frank orthogonal electrocardiogram. In 4 patients ventricular extrasystoles were indistinguishable from right bundle-branch complexes, and in another 4 from left bundle-branch complexes. In 25 patients ventricular extrasystoles showed an initial delay (greater than or equal to 20 msec) of the QRS, followed by an R loop, which in 13 patients resembled LBBB complexes, and 12 patients resembled RBBB complexes with an anterior clockwise loop in the horizontal plane. However, the frontal plane loop was often atypical of either RBBB or LBBB. In 51 patients ventricular extraplane loop was often atypical of either RBBB or LBBB. In 51 patients ventricular extrasystoles and an initial delay which was prolonged into the efferent limb of the QRS loop with acceleration of the afferent limb and/or the QRS loop was directed anteriorly, inferiorly and to the left. Conventional recordings of these extrasystoles usually showed an initial slow upstroke (or downstroke) of the QRS resembling a delta wave. It is suggested that extrasystoles resembling bundle-branch complexes arise close to the main bundle branches but that the other extrasystoles arise at the Purkinje-myocardial junction. Identification and differentiation of ventricular extrasystoles from aberrant conduction is aided by vectorcardiography.

Bundle-Branch Block↗
PubMed1986

[Ventricular extrasystole. Which should be treated and how?].

The decision of whether or not to treat a ventricular extrasystole depends in the first instance on the benign or severe nature of the disorder, and on whether there is subjacent cardiopathy. The results of 24-hour Holter monitoring, exercise tolerance tests and clinical and echographic examinations will define the pathological character of a ventricular extrasystole and will indicate any subjacent cardiopathy. Electrophysiological exploration with programmed stimulation should be reserved for so-called lethal cases of arrhythmia, such as attacks of sustained ventricular tachycardia. Ischemic cardiopathy is by far the most frequent cause of ventricular extrasystoles. The two major risks of sudden death after myocardial infarction are due to left ventricular dysfunction and repetitive and/or complex ventricular extrasystoles, as well as to attacks of ventricular tachycardia. Heart patients presenting these disorders must receive urgent treatment with antiarrhythmics. Isolated, monomorphic ventricular extrasystoles are also treated in heart patients at risk if their frequency is greater than 10 per hour, measured by 24-hour Holter monitoring. In the absence of subjacent cardiopathies, the therapeutic indications are much less well defined. Approximately five per cent of subjects in a normal population present ventricular extrasystoles, the frequency of which, however, rarely exceeds 100 per 24 hours. Repetitive phenomena are only seen in 10 per cent of cases. Attacks of ventricular tachycardia are almost never seen. Ventricular extrasystoles that develop in apparently normal hearts, but which do not fulfill the above criteria, can be considered abnormal. Nevertheless, there is no categorical proof that these ventricular extrasystoles represent any risk, notably of sudden death.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Arrhythmia Agents↗
PubMed1993

[The allorhythmic distribution of ectopic ventricular beats. Observations on the electrogenesis and dynamics of concealed ventricular extrasystole].

BACKGROUND: A regular distribution of ventricular ectopic beats is thought to be a relatively uncommon phenomenon, known as "concealed extrasystole". Several experimental studies suggest that the phenomenon originates from a "protected" ventricular focus. The aim of the present study was to evaluate the 24-hour ECG monitoring incidence of ventricular concealed extrasystole in patients with highly frequent ventricular ectopic beats, looking for signs useful in postulating the electrogenesis of the arrhythmia. METHODS: The 24-hour ECGs of 10 patients (pts) with highly frequent ventricular extrasystoles were analysed, searching for significant sequences in the distribution of ectopic beats (i.e., ectopic beats separated by a number of interectopic sinus beats fulfilling one of the formulas of concealed extrasystole). RESULTS: Five cases (50%) showed an allorhythmic distribution resulting in a prevalent pattern of concealed bigeminy (2n-1) in 3 cases, and concealed trigeminy (3n-1) in 2 cases. The phenomenon, however, showed a dynamic behaviour, alternating the distributions from patterns of concealed bigeminy to concealed trigeminy or less common patterns, and vice versa. The evidence of the pure ectopic cycle and mathematically related interectopic intervals in 2 cases, the variability of coupling intervals, and the presence of fusion beats in the remaining 3 cases, strongly suggests a parasystolic origin of the phenomenon. CONCLUSIONS: The results suggest the following: Concealed extrasystole is a relatively common phenomenon, at least in patients with highly frequent ventricular extrasystoles; the phenomenon, however, is somewhat underestimated due to prevalent quantitative, instead of qualitative, Holter monitoring analyses. Among patients with allorhythmically distributed ventricular extrasystoles, none showed only one pattern of distribution. In fact, each single patient showed two or more patterns throughout the 24-hour recordings. Changes from one pattern to another is governed by several factors, such as sinus heart rate and/or the influence of electrotonic "modulation" upon the ectopic focus. Ventricular extrasystoles with regular allorhythmic distribution show a significantly higher variability of coupling intervals than the others (p = 0.005).

Adolescent↗
PubMed1980

Limitations of post-extrasystolic potentiation in assessing regional myocardial viability in man.

UNLABELLED: To investigate the usefulness of regional response to post-extrasystolic potentiation as a predictor of left ventricular viability in patients with coronary artery disease, 46 patients underwent calibrated biplane left ventricular cineangiography during which a single, timed ventricular premature contraction was introduced. RESULTS: Of 758 normal or hypokinetic segments, 486 (64.1%) showed a positive response to post-extrasystolic potentiation. Of 116 akinetic or dyskinetic segments, only 51 (43.9%) showed a positive response to post-extrasystolic potentiation (P less than 0.001). Because akinetic or dyskinetic areas would not be expected to respond to post-extrasystolic potentiation based on animal laboratory data, alternative explanations were sought to explain such positive response in man. Analysis of percent change in chord length of normal or hypokinetic segments adjacent to akinetic or dyskinetic segments that did or did not respond to post-extrasystolic potentiation revealed (10.2% +/- 1.2%) vs (1.3% +/- 0.7%) improvement, respectively (P less than 0.001) (mean +/- SE). CONCLUSION: Passive rather than active events may be responsible for "improved" regional wall motion following post-extrasystolic potentiation in akinetic or dyskinetic regions. If unrecognized, these factors may lead to improper interpretation of "intervention ventriculography" utilizing post-extrasystolic potentiation.

Angiocardiography↗
PubMed1989

The influence of ventricular extrasystoles and postextrasystoles on cardiovascular dynamics in anesthetized dogs.

The influence of ventricular extrasystoles and postextrasystoles on cardiovascular dynamics were assessed in terms of maximum rate of rise of left ventricular pressure (max dP/dt), ascending aortic flow, left ventricular stroke volume, and left ventricular end-diastolic transverse dimension in anesthetized dogs. A single ventricular extrasystole, two and three consecutive ventricular extrasystoles (couplet and triplet) were induced by applying mechanical stimulation to the surface of the right ventricule. In any of these ventricular extrasystoles, max dP/dt, stroke volume and end-diastolic transverse dimension were decreased, compared with those in preceding sinus beats, i.e., pre-extrasystoles. Over the several postextrasystoles, max dP/dt was increased and gradually returned to its control level. This increase in max dP/dt, i.e., postextrasystolic potentiation paralleled an increase in ascending aortic peak flow but did not always bring about an increase in stroke volume, even when a left ventricular contraction was initiated by a significantly greater end-diastolic transverse dimension. The postextrasystolic potentiation seems to be associated with the Frank-Starling mechanism and does not compensate for the decreased in stroke volume elicited by the ventricular extrasystoles. In conclusion, not only ventricular extrasystoles per se but also postextrasystoles exert the adverse influence on cardiovascular dynamics consecutively.

Journal Article↗
PubMed1975

Measuring ventricular extrasystoles.

Uniform ventricular extrasystoles can be divided into three types: fixed coupling, parasystole, and variable non-parasystolic coupling. Frequency distributions of coupling intervals of ventricular extrasystoles were determined from long electrocardiographic recordings of 51 patients with variable coupling. These distributions were of five types: (a) two distinct coupling intervals, (b) a preponderance of extrasystoles with short coupling intervals and less frequent extrasystoles with progressively longer coupling, (c) a preponderance of long coupling intervals and less frequent extrasystoles with progressively shorter coupling, (d) an even distribution and (3) a central distribution. Interectopic intervals were measured in these electrocardiograms (ECGs). Parasystole was found only in three recordings. It is recommended that the diagnosis of parasystole be made only if the degree of variation of the ectopic cycle (both when it is manifest and when it is concealed) is less than the variation of the coupling intervals. When the ECGs with variable non-parasystolic coupling were compared with 44 ECGs with fixed coupling, it was found that variable coupling was associated with abnormalities of the basic electrocardiographic contour, multiformity of extrasystoles and repetitive extrasystoles.

Cardiac Complexes, Premature↗
PubMed1976

Mechanism of escape, extrasystolic, and parasystolic arrhythmias. Study on an electrical analogue.

A simple analogue of the heart consisting of a system of neon relaxation oscillators is presented. The analogue may display rhythm patterns similar to sinus rhythm, escape rhythm, isorrhythmic dissociation with synchronization, atrial extrasystoles, ventricular extrasystoles, and parasystole. The strict rules followed by these arrhythmias, as well as the deviations from the rules commonly followed by the equivalent heart arrhythmias, may be easily reproduced on the analogue. Such features are the Treppe phenomenon and captured beats in escape rhythm, fixed coupling intervals in extrasystoles, partial or complete atrioventricular block in very premature atrial extrasystoles, prolongation of the period following an atrial extrasystole, interpolated premature beats, complete compensatory pause and the rule of bigeminy in ventricular extrasystoles, slight instability of the parasystolic period, multiple length parasystolic periods slightly different from the exact multiples of the parasystolic idioperiod, preference of the parasystoles for certain phase in the sinus cycle, synchronization at a phase difference and fluctuation repeatedly and without interruption from a parasystolic to an extrasystolic rhythm and synchronization in escape rhythm with isorrhythmic dissociation. The mechanisms involved in these phenomena are discussed in detail. The striking similarity between the properties of the cardiac pacemakers and those of the relaxation oscillators on the one hand and betwen the rhythm patterns of the heart and those of the analogue on the other may permit the hypothesis that the mechanisms operating in the analogue may be used in analyzing and understanding heart arrhythmias.

Arrhythmias, Cardiac↗
PubMed1983

Ventricular extrasystoles during thiazide treatment: substudy of MRC mild hypertension trial.

One short term and one long term study of the relation between ventricular extrasystoles and thiazide treatment were carried out during the Medical Research Council's mild hypertension trial. In the short term study 110 patients were randomly assigned to one of three treatment groups, bendrofluazide with or without potassium supplements, or placebo. They were studied before starting treatment and nine to 10 weeks later while still taking their randomly assigned drugs. No significant increase in the number of ventricular extrasystoles was associated with short term thiazide treatment, although serum potassium concentrations changed as expected. In the long term study 214 patients who had completed an average of two years' treatment with randomly assigned bendrofluazide or a placebo were studied while continuing to take their trial tablets; the 214 included 20 people who had been randomised at entry to the bendrofluazide group and who had a subsequent history of hypokalaemia. These 20 patients were studied before and after being further randomised to two groups, one continuing treatment without change and one continuing with bendrofluazide and also taking potassium supplements. Counts of ventricular extrasystoles were significantly higher (p = 0.025) in those receiving long term thiazide treatment than in their controls; however, there was no significant association between the number of ventricular extrasystoles and serum potassium concentrations in this group, although the correlation between number of extrasystoles and serum urate concentrations was significant (p = 0.035). Pooled data for both studies showed a highly significant correlation between number of ventricular extrasystoles, and serum potassium concentrations (r = -0.185; p = 0.003), but the correlation with serum urate concentrations was of similar strength (r = 0.178; p = 0.004). These biochemical changes may be acting merely as markers of thiazide intake, and the explanation of the association between thiazide treatment and ventricular extrasystolic activity therefore remains uncertain.

Adult↗
PubMed1978

Supression of ventricular extrasystoles by perhexiline.

The antiarrhythmic effects of perhexiline were investigated in 13 of 20 patients with frequent and long standing ventricular extrasystoles in a double blind crossover trial using 24-hour electrocardiograph tape recordings, routine electrocardiograms, and treadmill exercise testing. With a dose of 300 to 400 mg per day, there was a significant decrease (mean 41%) in the number of ventricular extrasystoles per 24 hours. There were large differences in the individual responses to perhexiline, which were significantly related to the diurnal variations of ventricular extrasystoles: those patients whose ventricular extrasystoles disappeared spontaneously during sleep were less likely to respond to perhexiline than those whose ventricular extrasystoles persisted throughout the night. Suppression of ventricular extrasystoles was also apparent from the routine electrocardiogram and the exercise tests. Side effects (dizziness and unsteadiness) were troublesome in 5 of 20 patients. It is concluded that in selected patients perhexiline is an effective antiarrhythmic drug, and is likely to be most useful in patients with coexisting angina and ventricular extrasystoles. Because of its potential toxicity, it should not be used as a drug of first choice.

Cardiac Complexes, Premature↗
PubMed1985

[Efficacy and limits of magnesium therapy in extrasystole].

This study was carried out on a group of 19 patients with extrasystolic arrhythmia, the origin of which was atrial and/or ventricular. Its mean value was at least one extrasystole per minute. The patients were monitored by Holter for 24 h. In this population, we found a plasmatic and/or erythrocytic hypomagnesemia in two thirds of the patients. The simultaneous finding of an extrasystolic arrhythmia and of a lowering of magnesium values might be a mere coincidence. Treatment with intravenous magnesium salts did not significantly reduce the frequency of extrasystolic beats in any of our patients, utilizing the criteria of Morganroth, which are rather stringent. However, our treatment was beneficial in some cases; we noticed an average decrease of 20% in the extrasystolic beats during the 24-hour period. This response to magnesium treatment is somewhat irregular; some patients do not react at all. On the other hand, 3 patients reacted to our treatment during this period of 24 h with a decrease of 80% in their extrasystolic beats. We did not determine whether this effect remains after these first 24 h. It might be interesting to follow up these arrhythmias for several weeks after magnesium intake treatment, especially in patients having a proven deficiency at the beginning of this treatment. It seems beneficial, a priori, to remedy a magnesium-deficient state in any patient who has a persistent extrasystolic arrhythmia.

Adult↗
PubMed1983

[Occult ventricular bigeminy. Description of a case with extrasystole variable coupling separated by sinus beats in even or odd numbers].

We have analyzed an electrocardiogram showing many unifocal ventricular extrasystoles with wide variations of the coupling intervals. Ventricular bigeminy was frequent but in many instances more than one sinus beat occurred between two consecutive extrasystoles. In such a case the intervening sinus beats occurred indifferently both in odd and even numbers. Moreover, extrasystoles preceded by an even number of sinus beats had a relatively long coupling interval whereas extrasystoles that followed and odd number of sinus beats showed shorter coupling intervals. An opposite pattern of the coupling interval was observed with the extrasystoles that followed an interpolated premature ventricular depolarization. In such a case the coupling interval was long after an odd number of sinus beats and vice versa. This mechanism may be interpreted as due to concealed ventricular bigeminy caused by a ventricular ectopic focus which is surrounded by two different zones of block: a proximal zone of 2:1 block, and a distal one in which the block occurs irregularly. Unlike what appears in typical concealed bigeminy, characterized by only odd numbers of sinus beats between consecutive extrasystoles the intervening sinus complexes are indifferently in odd and even numbers. The constant relationship between the coupling interval and the number (odd or even) of sinus beats by which the extrasystole is preceded, allows us to recognize the presence of an atypical form of concealed bigeminy.

Aged↗
PubMed1983

[Mode of production of the splitting of the second heart sound in post-extrasystolic beats].

The changes in left and right ventricular systolic time intervals (LV- and RVSTIs) and split interval of the second heart sound (IIA-IIP interval) associated with post-extrasystolic potentiation were studied in 48 patients including 37 without a significant intracardiac shunt or valvular regurgitation or pulmonary hypertension, 7 with aortic stenosis (AS) and 4 with hypertrophic obstructive cardiomyopathy (HOCM). In 19 out of 37 patients mentioned above, LV- and RVSTIs were measured from carotid pulse and pulmonary arterial pulse waves, and IIA-IIP interval of post-extrasystolic beat with a compensatory pause was compared to that of the preceding sinus beat. In the other 29 patients including AS and HOCM, LVSTI, total electromechanical systole of the right ventricle (Q-IIP) and IIA-IIP interval were compared. There was no significant difference in the coupling index [(compensatory pause-coupling interval)/preceding RR interval X 100(%)] among three groups. The following results were obtained: In all patients without HOCM, post-extrasystolic beats showed wider IIA-IIP interval than the control beats independent upon the diseased entity and severity of cardiac function. In pts with HOCM, a IIA-IIP interval was shortened in post-extrasystolic beats. A IIA-IIP interval at post-extrasystolic beats was prolonged in proportion to the augmentation of coupling index. However, this finding was no longer observed in cases with the coupling index of more than 80%. LVSTI: In patients without HOCM, almost no change or prolongation of left ventricular ejection time (LVET) and shortening of left ventricular preejection period (LPEP) were observed in post-extrasystolic beats. The degree of changes in LVET and LPEP was greater in patients with the abnormal left-sided PEP/ET than in patients with the normal PEP/ET. The degree of changes in LPEP was always greater than that in LVET, therefore, total electromechanical systole of the left ventricle (Q-IIA) was shortened in all patients. In HOCM, a marked prolongation of LVET and a shortening of LPEP were observed. The degree of changes in LVET was greater than that in LPEP, therefore, Q-IIA was prolonged in all patients. RVSTI: Prolongation of right ventricular ejection time (RVET) and shortening of right ventricular preejection period (RPEP) were observed in all patients in post-extrasystolic beats. The degree of changes in RVET and RPEP was increased in patients with the increased right-sided PEP/ET. The degree of changes in RVET was greater than or equal to that in LPEP, therefore, Q-IIP showed slight prolongation or no change.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1978

[The effect of early appearing extrasystoles on systemic and coronary circulation].

In 10 anaesthesized dwarf pigs with an open thorax the effects of extrasystoles on systemic and coronary circulation were investigated. The actual effect of an extrasystole depends on the time of its onset. Early extrasystoles hamper the cardiac blood perfusion, with decreases in the stroke volume, mean arterial pressure, coronary blood flow, and elevation of coronary resistance. Extrasystoles setting on later are of minor haemodynamic and coronarodynamic importance. The effects of bigeminy and 2:1 extrasystolia are more adverse than the consequences of extrasystoles with later onset. With cumulation of several consecutive extrasystoles also adverse the haemodynamic coronarodynamic sequelae increase, in dependence on the magnitude of the quotient coupling time /extrasystolic excitation period [ greater than 1.1], or of the quotient: duration of pre- and postextrasystolic intervals/ normal interval of heart action [ greater than 1.5]. The authors point out the importance of haemodynamic findings during early extrasystoles in ischaemic heart disease.

Animals↗
PubMed1984

Concealed atrial bigeminy: mechanisms of disappearance and reappearance of manifest extrasystoles.

ECGs taken from four patients with concealed atrial bigeminy were analyzed to find the mechanisms of disappearance and reappearance of extrasystoles. Observations in three patients showing the classic form of concealed bigeminy suggest that when the extrasystole disappeared, the first sinus impulse after the last manifest extrasystole and its subsequent alternate sinus impulses passed through the reentrant pathway and thereafter became concealed extrasystoles. The other alternate sinus impulses appear to have been blocked within the reentrant pathway but after concealed conduction. It is suggested that such concealed conduction prolonged the conduction time of the next sinus impulse in the reentrant pathway and favored reappearance of the extrasystole. On the contrary, observations in one patient showing the even-number variant suggest that the first sinus impulse after a manifest extrasystole and its subsequent alternate sinus impulses were blocked in the reentrant pathway without appreciable concealed conduction.

Adult↗
PubMed1978

Comparison of the effects of sleep, exercise and autonomic drugs on ventricular extrasystoles, using ambulatory monitoring of electrocardiogram and electroencephalogram.

Ambulatory monitoring of the electrocardiogram (ECG) and the electroencephalogram (EEG) in 12 untreated patients with frequent ventricular extrasystoles showed a significant decrease in both ventricular extrasystoles and heart rate during sleep. The decrease in ventricular extrasystoles correlated more closely with the change in heart rate than with the level of arousal. During wakefulness, similar changes in ventricular extrasystoles and heart rate could be produced by the intravenous administration of propranolol and, to a lesser extent, by phenylephrine. Exercise produced an initial increase in ventricular extrasystoles, with suppression at higher levels in most patients. Thus, the frequency of ventricular extrasystoles is usually reduced at both extremes of heart rate, and the changes that occur during sleep can be explained by autonomic mediation, with the sympathetic limb of the autonomic nervous system having a greater effect than the vagus.

Adult↗
PubMed2005

Malignant entity of idiopathic ventricular fibrillation and polymorphic ventricular tachycardia initiated by premature extrasystoles originating from the right ventricular outflow tract.

OBJECTIVES: The aim of this study was to assess the clinical characteristics and the efficacy of radiofrequency catheter ablation (RFCA) for idiopathic ventricular fibrillation (VF) and/or polymorphic ventricular tachycardia initiated by ventricular extrasystoles originating from the right ventricular outflow tract (RVOT). BACKGROUND: Ventricular fibrillation and/or polymorphic ventricular tachycardia are occasionally initiated by ventricular extrasystoles originating from the RVOT in patients without structural heart disease. METHODS: Among 101 patients without structural heart disease in whom RFCA was conducted for idiopathic ventricular tachyarrhythmias arising from the RVOT, we examined the clinical characteristics and the efficacy of RFCA in 16 patients with spontaneous VF and/or polymorphic ventricular tachycardia initiated by the ventricular extrasystoles originating from the RVOT. RESULTS: Among 16 patients, spontaneous episodes of VF were documented in 5 patients, and 11 patients had prior episodes of syncope. Holter recordings showed frequent isolated ventricular extrasystoles with the same morphology as that of initiating ventricular extrasystoles, and non-sustained polymorphic ventricular tachycardia with short cycle length (mean of 245 +/- 28 ms) in all 16 patients. Radiofrequency catheter ablation by targeting the initiating ventricular extrasystoles eliminated episodes of syncope, VF, and cardiac arrest in all patients during follow-up periods of 54 +/- 39 months. CONCLUSIONS: Our data suggest that the malignant entity of idiopathic VF and/or polymorphic ventricular tachycardia was occasionally present in patients with idiopathic ventricular arrhythmias arising from the RVOT. Radiofrequency catheter ablation was effective as a treatment option for this entity.

Adult↗
PubMed1976

[Effect of prajmalium bitartrate and procaine amide on ventricular extrasystoles (author's transl)].

Prajmalium bitartrate (Neo-Gilurytmal) was given to 19 patients, who had either runs of ventricular extrasystoles or frequent extrasystoles. The E. C. G. was continuously monitored on magnetic tape. At a dosage of 80 mg/d (20 mg every six hours) a significant reduction in ventricular extrasystoles was demonstrated on 20 separate occasions. After two hours extrasystoles decreased to 63% of the initial level. After six hours practically the full effect of the drug had been reached; the reduction in extrasystoles stabilized after 12 hours at an average of 30% of initial level. Ten hours after the last tablet had been taken the frequency of extrasystoles had risen to 57% of initial level. Comparison with procaine amide (3 g/d) in 14 patients revealed no significant difference between the two drugs. Prajmalium bitartrate was well tolerated, while three patients receiving procaine amide complained of nausea and gastrointestinal symptoms, so that treatment had to be discontinued in two. In one patient, receiving procaine amide by continuous drip, there were reversible joint pains, resembling lupus erythematodes.

Adult↗