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At least 19 recordsLinked to original sources

PubMed1985

[Predictive value of the ajmaline test in dysfunction of the sinus node. Prospective 4-year follow-up relative to 77 patients].

To establish the usefulness of Ajmaline test for the evaluation of sinus node function, 77 pts (47 M, 30 F, mean age +/- SD = 61 +/- 15 yrs) first underwent an electrophysiologic study and then were followed-up for a mean period of 46.3 months. The following parameters were determined before and after i.v. administration of Ajmaline (1 mg/kg in 1 minute): sinus cycle length (SCL), corrected sinus node recovery time (CSNRT) and sino-atrial conduction time (SACT). The pts were divided into 3 groups: Group A: 10 pts without clinical or electrocardiographic signs of sinus node dysfunction (SND) and with normal control CSNRT and SACT (less than or equal to 500 and less than or equal to 120 msec, respectively); Group B: 46 pts with clinical-electrocardiographic signs of suspected or apparently not severe SND (sinus bradycardia greater than or equal to 40 beats/min and/or syncopes with positive vagal manoeuvres) and/or slightly abnormal control CSNRT (greater than 500 less than or equal to 600 msec) and/or SACT (greater than 120 less than or equal to 150 msec); Group C: 21 pts with clinical-electrocardiographic signs of apparently severe SND (sinus bradycardia less than or equal to 39 beats/min, sino-atrial block, sinus arrest) and/or definitely prolonged control CSNRT and/or SACT (greater than 600 and greater than 150 msec, respectively). The Ajmaline test was considered negative for the presence of a severe SND if SCL was not prolonged after the administration of the drug more than 20% and CSNRT and SACT were not prolonged more than 50% compared to the control values. Otherwise the Ajmaline test was considered positive. Twenty-seven out of the 77 pts studied underwent permanent pacemaker implantation (23 immediately after the electrophysiologic study and 4 during the follow-up). The following results were obtained: the Ajmaline test was negative in 100% of group A, 87% of group B and 48% of group C pts and positive in 0% of group A, 13% of group B and 52% of group C pts; during the follow-up a negative test resulted predictive in 56 out of 60 pts (92%) and a positive test in 16 out of 17 pts (94%). The predictive accuracy of the test was, therefore, 93.5%. These results indicate that Ajmaline test is an useful provocative test for disclosing, during electrophysiologic studies, pts who have severe SND and for selecting those who need pacemaker implantation.

Adolescent↗

PubMed1981

[Predictive value of the ajmaline test for the diagnosis of distal paroxysmal atrioventricular block (author's transl)].

An ajmaline test was conducted in 120 patients with a history of disorders of consciousness : Adams-Stokes syndrome (n = 49), loss of consciousness (n = 42), or lipothymia (n = 29). Four types of response were observed after ajmaline : VH less than 80 ms (n = 63); VH between 80 and 100 ms (n = 19); VH greater than 100 ms (n = 17); distal block (n = 21). One hundred and fifteen of these patients were followed-up for from three to six years (mean 56 months). Pacemakers had been fitted in 46 of them. Atrioventricular block was eventually detected in 37 patients but was excluded in the other 78 cases, either because the syncope attacks did not recur or because another cause was demonstrated. The predictive value of the ajmaline test was confirmed by the subsequent course of the disorders. Based on only clinical findings, diagnosis was confirmed in 42 p. cent, excluded in 12 p. cent, and impossible to define in 46 p.cent of cases. After the ajmaline test, diagnosis was confirmed in 79 p.cent, excluded in 6 p.cent, and impossible to define in 15 p.cent. The risk of atrioventricular block can be evaluated as 1-6 p.cent when the increase in VH is less than 80 ms, 35.3 p.cent when the increase is between 80 and 100 ms, 62.5 p.cent when it is greater than 100 ms, and 100 p.cent when there is a distal block. The indications for fitting a pacemaker depend upon the results of this test. If contra-indications are respected (recent history of an infarct, cardiac failure, marked enlargement of the heart), complications are rare, being observed in less than 3 p.cent of cases.

Aged↗

PubMed1982

[The ajmaline test in identifying patients at high risk of developing complete paroxysmal atrioventricular block].

In thirty-one patients (pts) with atrioventricular or intraventricular conduction disturbances, the Ajmaline test was used to evaluate the risk of evolution to complete atrioventricular block. Three groups of patients were identified: A = nine patients without history of syncope or dizziness; B = seventeen pts with history of syncope or dizziness but without evidence of complete atrioventricular block; C = five pts with recorded atrioventricular block and history of syncope or dizziness. All patients with symptoms (B-C groups) and with a positive Ajmaline test (i.e. HV greater than or equal to 90 msec.) were paced with regression of symptoms. All patients without symptoms (A group) and with a positive Ajmaline test (i.e. HV greater than or equal to 90 msec.) were not paced and did not progress to complete atrioventricular block in a follow-up period of two years. Our results confirm that the Ajmaline test is useful in demonstrating the cardiac origin of syncopal episodes, but an HV value of 90 msec, does not seem to be specific enough in identifying asymptomatic patients at risk of developing complete atrioventricular block.

Adult↗

PubMed1994

[The clinical significance of the ajmaline test in the noninvasive diagnosis of the Wolff-Parkinson-White syndrome].

A knowledge of electrophysiological parameters of accessory atrioventricular conduction pathways, such as effective refractory time and high conduction capacity in atrial fibrillation, make it possible to detect those patients who are at risk of life-threatening ventricular tachyarrhythmias. One criterion to identify these electrophysiological parameters is persistent pre-excitation after intravenous administration of ajmaline in Wolff-Parkinson-White (WPW) syndrome. Sensitivity and specificity of the ajmaline test in detecting patients at risk of life-threatening ventricular tachyarrhythmias were evaluated in 58 consecutive patients (22 females, 36 males; mean age 40.2 +/- 13 years) with the WPW syndrome. Pre-excitation was blocked after ajmaline in 43 patients (74%), pre-excitation persisting in 15 (26%). In 26 of the 43 patients with blocked pre-excitation the ajmaline test indicated short effective refractory time (< 270 ms) of the accessory pathway, and a high conduction capacity in 19 (minimal pre-excitation R-R interval during atrial fibrillation of < 250 ms). Sensitivity of the ajmaline test in the detection of a short refractory time was 33.3%, specificity 89.4%, while the corresponding values were 40.6% and 92.3% for the detection of accessory pathways with high conduction capacity in atrial fibrillation. These data show that the ajmaline test is not useful for estimating the electrophysiological characteristics of the accessory pathways. It is thus of only subordinate diagnostic value in predicting how much patients with the WPW syndrome are at risk of serious ventricular tachyarrhythmias.

Adult↗

PubMed1989

The ajmaline test as a method to disclose latent experimental Chagas' heart disease.

Forty-one chronically T. cruzi-infected male adult albino rats with normal resting ECG were submitted to the ajmaline test (1 mg/kg body weight injected into the dorsal vein of the penis). Twenty-one similar noninfected animals served as controls. Ajmaline induced the following ECG alterations in control rats: A decrease in heart rate, an increase in heart rate, an increase in P-wave duration, an increase in PR interval, lengthening of the QRS complex, and left axis deviation in 33%, 28%, 14%, 90%, 100%, and 33% of the animals, respectively. Ajmaline evoked similar alterations in 29 of 41 (71%) T. cruzi-infected rats. However, 12 of 41 (29%) infected rats showed ECG changes of a magnitude not seen in controls: P-wave enlargement, first-degree AV block, lengthened QRS complex, and first-degree AV block plus lengthened QRS complex in 7%, 12%, 14%, and 4% of the animals, respectively. Microscopical lesions were not found in control rats. However, 22 of 41 (53%) infected rats were found to have the following pathological lesions: mononuclear cell infiltrate, necrosis, myocyte vacuolization, and interstitial fibrosis in 56%, 39%, 29%, and 7% of the animals, respectively. By comparing the ECG changes evoked by ajmaline not seen in controls with the concomitant pathological lesions, the ajmaline test was found to have 54% sensitivity, 100% specificity, and 100% positive predictive value. Thus, the ajmaline test appears to be useful for unmasking myocardial disease and therefore may be considered a potential method for the full characterization of the indeterminate form of Chagas' disease in experimental animals.

Ajmaline↗

PubMed2004

Results of ajmaline testing in patients with arrhythmogenic right ventricular dysplasia-cardiomyopathy.

An association between arrhythmogenic right ventricular dysplasia-cardiomyopathy (ARVD/C) and Brugada syndrome can be supposed according to several case reports. In order to examine a possible link between ARVD/C and Brugada syndrome, systematic ajmaline testing with 1 mg/kg body weight intravenously, was done in 55 patients (32 males, mean age 46.7+/-12.3 years) with ISFC/ESC criteria of ARVD/C. In nine patients ajmaline testing could demonstrate coved ST segment elevation of at least 2 mm in at least two right precordial leads. Three of these patients had recurrent syncopes. Electrophysiological study revealed non-sustained ventricular tachycardia with left bundle branch block configuration and inferior axis in only one case. Systematic ajmaline testing could demonstrate a definite link between ARVD/C and Brugada syndrome.

Adult↗

PubMed1987

Electrocardiographic changes in T. cruzi-infected rats after the ajmaline test.

Fifty-eight chronically T. cruzi-infected rats and 26 control rats were submitted to the ajmaline test (1 mg/kg, i.v. during ECG monitoring) after obtaining the resting ECG. Abnormal ECG tracings were detected in the resting ECG of 26 (44%) infected rats. After ajmaline injection, a decrease in heart rate was observed in control but not in infected rats. P wave enlargement, lengthening of the QRS complex, and increase of the PR as well as the QaT intervals were detected in all animals. Ajmaline induced right axis deviation in 7% of the control rats and left axis deviation in 26% of the controls, as well as in 23% of the T. cruzi-infected rats with abnormal resting ECG. However, after ajmaline injection, 7 (21%) of the 32 infected rats having normal resting ECG presented the following ECG changes not observed in control animals: indeterminate axis (15%), marked increase in PR interval and bizarre QRS complex (3%), and marked decrease in heart rate plus a significant increase in PR interval. These data show that ajmaline induces important ECG changes not only in controls, but also in T. cruzi-infected rats. Furthermore, since severe ECG changes occurred only in T. cruzi-infected rats having normal resting ECG, the ajmaline test can be used to unmask cardiac lesions in experimental chronic Chagas' disease.

Ajmaline↗

PubMed1986

Comparison of exercise and ajmaline tests with electrophysiologic study in the Wolff-Parkinson-White syndrome.

Ajmaline test (50 mg intravenously over 1 minute) and ergometric exercise test were performed in 24 patients with the Wolff-Parkinson-White syndrome. The effects of both tests on the conduction in the accessory pathway (AP) were correlated with the anterograde effective refractory period (ERP) of the AP. Ajmaline caused transient anterograde block in the AP in 15 patients, 14 with an ERP of more than 250 ms and 1 with an ERP of 250 ms. Ajmaline failed to abolish preexcitation in 9 patients, all with ERP of the AP of 250 ms or less. Exercise testing caused anterograde block in the AP in 5 patients, in 2 during exercise (ERP of 340 and 360 ms) and in the remaining 3 patients during the recovery phase (ERP of 600, 520 and 460 ms). Of the 10 patients with an ERP of 250 ms or less, ajmaline did not abolish preexcitation in 9 and exercise did not abolish it in any of them. Of the 7 patients with an ERP of 330 ms or more, ajmaline abolished preexcitation in 7 and exercise abolished it in 5 patients. Of the 7 patients with ERP of the AP more than 250 ms but less than 330 ms, ajmaline but not exercise abolished preexcitation in all. Thus, ajmaline and exercise testing can detect patients with short and long ERPs of the AP, respectively, and the effects of ajmaline and exercise tests combined may be useful in the noninvasive assessment of various ranges of ERP of the AP.

Adult↗

PubMed1983

[Evaluation of the response to the ajmaline test in the diagnosis of paroxysmal atrioventricular blocks].

Between October 1973 and December 1981, 31 symptomatic patients who underwent pacemaker therapy on the results of a positive Ajmaline test alone, showing infrahisian AV block, were followed up clinically and electrocardiographically. The mean follow up from the date of implantation was 30 months. Two groups of patients were identified according to the results of electrophysiological investigations and clinical and electrocardiographic follow-up: --group I: 13 patients with either infrahisian AV block or an HV interval greater than or equal to 120 ms after Ajmaline; --group II: 18 patients with an HV interval less than 120 ms after Ajmaline. During follow-up, the 5 AV blocks observed out of the 7 documented at inhibition of the pacemaker and the only two cases of deterioration of the intraventricular conduction during sinus rhythm occurred in Group I. The only discriminating variable between the two groups before the implantation of a pacemaker was the response to the Ajmaline test. The difference of the results of the electrical outcome between the two groups was statistically significant (p less than 0,03). During the same study period this critical value was observed in 49 other patients with a basal HV greater than or equal to 70 ms. In this group, 20 developed infrahisian AV block after Ajmaline, 26 had a HV interval greater than or equal to 120 ms and only 3 cases had HV intervals of 100 ms. These results suggest that a HV interval greater than or equal to 120 ms after Ajmaline has the same significance as infrahisian block produced by the drug.

Aged↗

PubMed1982

[Cardiac toxicity of ajmaline. Comparison of acute voluntary poisoning with complications of the ajmaline test].

A comparative and retrospective study of 59 cases of acute voluntary self-poisoning observed at the Toxicology Department of Fernand Widal Hospital, and 15 cases of complications of the Ajmaline test observed in the Cardiology Department of Bichat Hospital showed a similarity in the cardiac effects of high dosage regardless of the mode of administration of the antiarrhythmic. Acute suicidal poisoning in adults or accidental poisoning in children caused toxic effects at doses over more than Ig: they are characterised by their sudden onset after a latent period of 1 to 2 hours and their short duration (no effects after the 12th hour). The ECG changes included:--First degree atrioventricular block (15 p. 100).--Intraventricular conduction defects were observed in almost all cases. They were proportional to the dose taken and were of prognostic interes (no cardiac arrests when the QRS remained less then 0,2 sec).--ST-T wave changes were observed in all patients. They lasted longer and were of no prognostic importance.--Extrasystoles and ventricular tachycardia are nearly always associated with poor hemodynamic tolerance (70 p. 100 of cardiac arrests, compared to only 16 p. 100 in this absence). This intoxication is serious with a mortality of 24 p. 100 of the reported cases and of 9 p. 100 of cases admitted to an Intensive Care Unit.--The complications of the Ajmaline test were similar, the time of apparition being a few minutes instead of a few hours. There were no deaths or serious hemodynamic complications in this series. This is without doubt related to the observation of the contraindications and the fractional administration of the Ajmaline. We conclude that oral Ajmaline, though well tolerated at therapeutic does may cause severe toxic overdose effects. Although its use remains justified in the treatment of arrhythmias, it should not be used for the symptomatic treatment of palpitations and neurovegetative imbalance.

Acute Disease↗

PubMed2004

Value of electrocardiographic parameters and ajmaline test in the diagnosis of Brugada syndrome caused by SCN5A mutations.

BACKGROUND: The Brugada syndrome is an arrhythmogenic disease caused in part by mutations in the cardiac sodium channel gene, SCN5A. The electrocardiographic pattern characteristic of the syndrome is dynamic and is often absent in affected individuals. Sodium channel blockers are effective in unmasking carriers of the disease. However, the value of the test remains controversial. METHODS AND RESULTS: We studied 147 individuals representing 4 large families with SCN5A mutations. Of these, 104 were determined to be at possible risk for Brugada syndrome and underwent both electrocardiographic and genetic evaluation. Twenty-four individuals displayed an ECG diagnostic of Brugada syndrome at baseline. Of the remaining, 71 received intravenous ajmaline. Of the 35 genetic carriers who received ajmaline, 28 had a positive test and 7 a negative ajmaline test. The sensitivity, specificity, and positive and negative predictive values of the drug challenge were 80% (28:35), 94.4% (34:36), 93.3% (28:30), and 82.9% (34:41), respectively. Penetrance of the disease phenotype increased from 32.7% to 78.6% with the use of sodium channel blockers. In the absence of ST-segment elevation under baseline conditions, a prolonged P-R interval, but not incomplete right bundle-branch block or early repolarization patterns, indicates a high probability of an SCN5A mutation carrier. CONCLUSIONS: In families with Brugada syndrome, the data suggest that ajmaline testing is valuable in the diagnosis of SCN5A carriers. In the absence of ST-segment elevation at baseline, family members with first-degree atrioventricular block should be suspected of carrying the mutation. An ajmaline test is often the key to making the proper diagnosis in these patients.

Ajmaline↗

PubMed1991

Ajmaline test in a patient with chronic renal failure. A pharmacokinetic and pharmacodynamic study.

Pharmacokinetic and pharmacodynamic properties were studied after intravenous administration of ajmaline 1 mg/kg in an anuric patient, who underwent the electrophysiological ajmaline test. The magnitude and rate of onset of the typical electrophysiological effects of ajmaline (prolongation in atrio-Hisian and His-ventriculum conduction times) were within the range of normal values. The plasma concentration curve showed a triexponential decay with half-lives as follows: initial phase (t1/2 alpha) 1.34 min, fast elimination phase (t1/2 beta) 10.13 min and terminal (slow) phase (t1/2 gamma) 258.6 min. Other relevant pharmacokinetic parameters calculated were: total plasma clearance 45.91 L/h; volume of distribution 285.6L; protein binding 47%. Five hours after administration the patient underwent a 3.5h haemodialysis without any substantial increase in the slope of the final elimination phase of the curve. A major problem in interpreting the pharmacokinetic results is the lack of reliable reference data in healthy subjects. It is likely that the ajmaline t1/2 reported in the literature (13.4 min) does not reflect the true terminal t1/2 of the drug, because it was determined during an unduly short sampling period (30 min). Nevertheless, if we compare just the first 30 min of the concentration-time curves, our results are nearly superimposable on those found in healthy subjects.

Aged↗

PubMed2003

Unusual response to the ajmaline test in a patient with Brugada syndrome.

We present a Brugada syndrome patient who suffered an aborted sudden death. The ajmaline test (1 mg/kg body weight) induced accentuated alternans ST-segment elevation in V1-V2 without ventricular arrhythmias. It could represent silent ischaemia not detected before, failure of myocardial regions to repolarize in alternate beats due to transmural dispersion of conduction and refractoriness in the right ventricular outflow tract or a rate dependent sodium channel block by ajmaline. We need more studies to know whether this electrocardiographic sign is a risk factor for life-threatening ventricular arrhythmias in Brugada syndrome patients.

Ajmaline↗

PubMed1989

Diagnosis of dual accessory pathways by ajmaline test.

In a patient with the Wolff-Parkinson-White syndrome, the existence of dual accessory pathways, both right-sided, was suspected during ajmaline test and confirmed during electrophysiologic study. The first accessory pathway was manifest in sinus rhythm while the second was obscured and revealed during low right atrial pacing. Ajmaline abolished conduction over the first pathway which most probably had a long refractory period allowing manifestation of the second pathway which had a very short refractory period. A longer conduction time over the second accessory pathway was suggested to explain its concealment during sinus rhythm.

Adult↗

PubMed2006

Recording of high V1-V3 precordial leads may be essential to the diagnosis of Brugada syndrome during the ajmaline test.

Sodium channel-blocking agents are routinely used to unveil the Brugada syndrome in patients in whom the typical electrocardiographic pattern is absent or doubtful. In this article, the authors report a patient with syncopal episodes of unknown origin in whom the conventional electrocardiographic result was normal and a negligibly small "saddle back" type repolarization was present in lead V2 recorded 2 intercostal spaces above the conventional site. Intravenous ajmaline (50 mg) did not elicit the type 1 pattern of the Brugada syndrome in the precordial leads obtained at their usual level, but a clear-cut coved-type repolarization was apparent in high right precordial leads. These findings indicate that high precordial leads should be routinely recorded while assessing the ajmaline test in patients suspected of having the Brugada syndrome.

Adult↗

PubMed1992

[Mitral valve prolapse. Atrial stimulation, ajmaline test and "pharmacological denervation" in the evaluation of ventricular repolarization].

In patients with mitral valve prolapse syndrome (MVP) various electrophysiological abnormalities occur. There are convergent opinions concerning QT distance variability and the influence of autonomic nervous system on ventricular repolarization in this syndrome. In 38 MVP patients (group I) and 24 subjects without this abnormality (group II) ecg was recorded during transvenous right atrial pacing at baseline, after ajmaline administration and after pharmacological autonomic blockade (atropine + propranolol). The following ventricular repolarization parameters were analysed: QTe (distance to the end of T wave), JTe (distance between J point and the end of T wave--so called "pure repolarization"), QTdys (repolarization dispersion) and the corrected QTc.QTe during 90/min right atrial pacing was significantly shorter than QTc in both groups. QTc was abnormally prolonged (above 440 msec) in MVP group. Ajmaline administration prolonged QTe in group II only, whereas autonomic blockade resulted in marked shortening of QTe in MVP group. QTdys was significantly prolonged only after ajmaline administration in group II. Based on above results, the following conclusions are made: 1) Right atrial pacing technique may be used for calculating standardized QT distance, an alternative to corrected QT. 2) Ajmaline test is useless in ventricular repolarization estimations in MVP patients. 3) In MVP patients the influence of adrenergic system on ventricular repolarization at rest appears to be greater than in non-MVP subjects.

Adolescent↗

PubMed1985

Two false-negative responses to the ajmaline test in the Wolff-Parkinson-White syndrome.

Anterograde block in the accessory pathway with a short effective refractory period was observed after intravenous (IV) injection of 1 mg/kg of ajmaline in two patients with the Wolff-Parkinson-White syndrome. The possibility of a false-negative response to this test is discussed. Ajmaline is proposed as an emergency drug in the Wolff-Parkinson-White syndrome in the setting of atrial fibrillation with a very high ventricular rate.

Adult↗

PubMed1982

Usefulness of the ajmaline test in patients with latent bundle branch block.

Twelve patients were studied with intermittent bundle branch block whose conduction disturbance disappeared completely and could no longer be recorded even after provoked changes in heart rate. Premature atrial stimulation and atrial pacing at rapid rates were performed in nine patients; in none of these nine were these procedures able to evoke the complete bundle branch block pattern that all patients exhibited before the spontaneous normalization of conduction. In marked contrast, the administration of ajmaline (1 mg/kg body weight, intravenously in 90 seconds) caused the bundle branch block pattern to reappear in 10 (83.3 percent) of the 12 patients 30 to 120 seconds after the end of the injection, and in 11 patients (91.6 percent) when additional atrial stimulation was performed in 1 of the 2 "failures." This pharmacologic test was much more rapid and simple than electrophysiologic testing and it was noninvasive. Results of this study suggest that some form of subclinical fascicular injury was present (or had persisted) at a time when intraventricular conduction was persistently normal even though no significant physiologic alteration could be demonstrated by the atrial stimulation techniques. The ajmaline test may become a valuable tool for uncovering cases of latent bundle branch block and furthering our knowledge of the early natural history of intraventricular block.

Adult↗