Adenosine 5'-Triphosphate Test in the Management of Patients With Syncope.

The response to adenosine 5'-triphosphate (ATP) identifies patients with syncope who might benefit from pacemaker therapy (ATP test). Two measures have been used to determine the outcome of the ATP test, which have lead to contrasting conclusions regarding its utility: (1) the duration of cardiac pause (CP) mainly due to AV block and (2) the longest RR interval (RRmax). We tested the hypothesis that the discrepancy regarding the utility of the ATP test is mainly because of the different way the 2 measures determine the outcome of the test.

Treatment of unexplained syncope: a multicenter, randomized trial of cardiac pacing guided by adenosine 5'-triphosphate testing.

Background: The origin of 40% of syncope cases remains unknown even after a complete diagnostic workup. Previous studies have suggested that ATP testing has value in selecting successful therapy. This patient-blinded, multicenter, randomized superiority trial tested whether, in patients with syncope of unknown origin, selecting cardiac pacing in those with a positive ATP test leads to fewer recurrences than those who do not receive pacing.

ATPace™: injectable adenosine 5'-triphosphate : Diagnostic and therapeutic indications.

ATPace™, a novel injectable formulation of adenosine 5'-triphosphate (ATP), is developed by Cordex Pharma, Inc. (Cordex) as a diagnostic and therapeutic drug for the management of cardiac bradyarrhythmias. Extracellular ATP exerts multiple effects in various cell types by activating cell-surface receptors known as P2 receptors.

Symptoms during ATP-test under pacing: impact on syncope recurrence and prediction from the ATP-test without pacing.

Syncope recurrence in patients with positive ATP-test who underwent permanent pacemaker implantation is suspected to be related to vagal vasodilatation. We studied symptoms during ATP-test in 38 temporary paced patients. Among patients with positive ATP-test who underwent permanent pacemaker implantation (N = 14), the only one patient who recurred during follow-up was symptomatic during the initial paced ATP-test.

Blood pressure drop and symptoms during ATP-test under pacing.

We studied systolic blood pressure (SBP) behavior and symptoms during ATP-test in temporary paced patients. SBP drop during ATP-test is only partially prevented by pacing. During DDD paced ATP-test, SBP minimum was lower in symptomatic patients.

Brady-tachy syndrome: rapid atrial pacing efficacy in preventing atrial fibrillation recurrence assessed by reliable electrograms: the prefib pilot study.

Aims: Recent studies have tested different atrial pacing rates, modes, and sites for preventing atrial fibrillation (AF) recurrence. Present generation pacemakers offer reliable electrograms (EGMs) storage for optimizing the arrhythmia diagnosis. Based on these EGMs, the study objective was to assess the rate of AF recurrence at two different pacing rates.

[The adenosine-5'-triphosphate (ATP) test: a diagnostic tool in the management of syncope of unknown origin. Basic and clinical aspects].

The prevalence of syncope increases in elderly population. An inappropriate reflex reaction of the autonomous nervous system in specific circumstances is responsible for symptoms in more than 50% of cases. These neurocardiogenic or vasovagal syncopes are due to a vasoplegia or to a cardio-inhibitory reflex or to the association of both mechanisms.

Is a pacemaker indicated for vasovagal patients with severe cardioinhibitory reflex as identified by the ATP test? A preliminary randomized trial.

Background: A previous observational study suggested that, in syncopal elderly patients with vasovagal syndrome, a test using adenosine-5'-triphosphate (intravenous ATP 20 mg. 2 ml-1) could identify a subgroup of patients at high risk of severe cardioinhibitory response and guide the therapeutic strategy. To test one aspect of these results prospectively, we designed a small study focusing only on vasovagal patients with abnormal response to ATP testing.

Contribution of head-up tilt testing and ATP testing in assessing the mechanisms of vasovagal syndrome: preliminary results and potential therapeutic implications.

Background: In patients with vasovagal syndrome, head-up tilt testing may reproduce symptoms generally associated with vasodepression. Recent research suggests ATP testing identifies patients with abnormal vagal cardiac inhibition. This preliminary study examined the joint contribution of both tests in identifying underlying mechanisms in the general population with vasovagal syndrome.

[A randomized double-blind trial comparing cibenzoline and disopyramide in the prevention of recurrences of atrial tachyarrhythmia].

The aim of this multicenter, randomised, double-blind trial was to compare the efficacy and tolerance of oral disopyramide (D: 250 mg slow release twice daily) compared with cibenzoline (C: 130 mg twice daily) in the prevention of recurrences of atrial arrhythmias over a 6 month period. Sixty patients (mean age: 62 +/- 14 years; 37 men, 23 women; cardiac disease in 60% of cases) were randomised to two groups: C (N = 31) and D (N = 29). The commonest arrhythmia was atrial fibrillation (83%).

Reproducibility of the adenosine-5'-triphosphate test in vasovagal syndrome.

Introduction: Adenosine-5'-triphosphate (ATP) provokes negative chronotropic and dromotropic vagal effects. In vasovagal syndrome, ATP test (20-mg i.v.

Early increase of von Willebrand factor predicts adverse outcome in unstable coronary artery disease: beneficial effects of enoxaparin. French Investigators of the ESSENCE Trial.

Background: The pathogenesis of unstable angina and non-Q-wave myocardial infarction is still poorly understood, and early evaluation of prognosis remains difficult. We therefore studied the predictive value of 5 biological indicators of inflammation, thrombogenesis, vasoconstriction, and myocardial necrosis, and we examined the effects of enoxaparin and unfractionated heparin on these markers after 48 hours of treatment.

Methods And Results: Sixty-eight patients with unstable angina or non-Q-wave myocardial infarction randomized in the international ESSENCE trial participated in this French substudy.

Can adenosine 5'-triphosphate be used to select treatment in severe vasovagal syndrome?

Background: Selection of treatment in vasovagal syndrome should be guided by the mechanism of symptoms. This study determined whether a simple drug test may assess one mechanism.

Methods And Results: To identify patients at risk of severe cardioinhibitory response of vagal origin, we infused 20 mg ATP into 316 patients hospitalized for recurrent syncope (n=195) or presyncope (n=121) of unknown origin and into normal subjects (n=51).

Acute and long-term efficacy of perindopril in severe chronic congestive heart failure.

To assess the short- and long-term hemodynamic efficacy of perindopril, 15 patients (12 men and 3 women) diagnosed with congestive heart failure were treated with oral perindopril (4 mg daily) for 3 months in association with digitalis and diuretic maintenance therapy. Patients were in New York Heart Association (NYHA) functional classes III and IV. Underlying cardiopathy was ischemic (6 patients), hypertensive (5 patients), valvular (2 patients), and dilated cardiomyopathy (2 patients).

Amplitude and direction of atrial depolarization using a multipolar floating catheter: principles for a single lead VDD pacing.

VDD stimulation using a single catheter for atrial sensing and ventricular sensing and pacing has become a reality. In order to compare the quality of the cavitary atrial electrogram (AEG) and to determine the intraatrial P wave direction and conduction time (CT), we compared, in an acute study, three different types of atrial electrode systems using four different leads, in 53 patients in sinus rhythm. The three electrode systems were: (1) one experimental system with quadripolar orthogonal electrodes using the Goldreyer concept; (2) one experimental system with quadripolar whole ring electrodes; (3) two systems with diagonally oriented half-ring electrodes, one experimental quadripolar and one bipolar CCS commercial (Polysafe A-Track lead).

[Intravenous enoximone versus conventional treatment in acute lung edema. Preliminary results of a randomized study].

The aim of this open study was to compare the efficacy of Enoximone and conventional treatment in 44 patients with acute pulmonary edema. At the time of this interim analysis, 22 patients had received Enoximone (1 mg/kg by rapid intravenous injection every 8 hours for 48 hours) and 22 were given conventional treatment (furosemide, nitrates, dopamine-dobutamine). The treatment schedules were randomised.

Acute pulmonary oedema: preliminary results of a randomized trial of the intravenous phosphodiesterase inhibitor, enoximone, vs conventional therapy.

The purpose of this open study was to compare the effects of enoximone and conventional therapy in 44 patients with acute pulmonary oedema. In this preliminary report, 22 patients were randomly assigned to the enoximone group (1 mg/kg bolus, every 8 hours for 48 hours) and 22 patients to conventional therapy (frusemide, nitrates, dopamine-dobutamine). Patients were assessed clinically at 0, 1, 2, 24 and 48 hours by the change in their Killip-Kimball score, dyspnoea, pulmonary rales, blood pressure, diuresis, requirement for additional therapy and/or death.

[Acute thrombosis of mitral Starr prosthesis. Value of color coded two-dimensional doppler echocardiography].

In a case of acute thrombosis on mitral Starr valve two-dimensional doppler-echocardiography rapidly showed that parts of the transprosthetic jets had disappeared, while conventional continuous wave doppler ultrasound confirmed the presence of a severe haemodynamic obstacle. With colour-coded doppler ultrasound, there only remained a jet that was parallel to the posterior wall of the left ventricle. This jet was of unusual pattern, with the presence of turbulence and high velocities in aliasing colour.

Myocardial infarction: is bepridil, a new calcium antagonist, able to improve the course of the acute phase?

Several calcium antagonists are useful in the treatment of ischemic heart disease. This open randomized study was designed to determine the effects of bepridil, a new long-acting calcium antagonist with antiarrhythmic properties, on the course of acute myocardial infarction (AMI). Two hundred patients with AMI of less than 48 hours duration (average 10.

[Anti-arrhythmia effect of long-term encainide in chronic ventricular extrasystole].

The long term efficacy and tolerance of encainide were studied in 48 patients with chronic/ventricular extrasystoles (VES) treated for 6 months. Holter monitoring was performed before treatment and at each dose increment (75 mg/day; 150 mg/day and 225 mg/day) during the first week of titration, and then after 1 month and 6 months of treatment. The dose administered in the long-term study corresponded to the minimum effective dose during the titration phase (the dose which reduced the number of VES/24 hours by at least 75%).

Long-term efficacy and safety of oral encainide in the treatment of chronic ventricular ectopic activity: relationship to plasma concentrations--a French multicenter trial.

To establish long-term efficacy and safety of encainide, 48 patients with chronic premature ventricular contractions (PVCs) underwent 6 months of therapy with encainide. Twenty-four-hour ambulatory ECGs were obtained at baseline for each daily dosage of 75 mg, 150 mg, and 225 mg of encainide during the in-hospital titration period and at the end of the first and sixth months during the follow-up period. There was a significant reduction in the median hourly total PVC rates from 480.

[The value of temporary electrosystolic pacing for treating low output in posterior necrosis with adiastole].

Early catheterisation was performed in 27 patients with an acute inferior myocardial infarction less than 3 days old complicated by signs of low output with right ventricular dysfunction. All patients had hemodynamic criteria of adiastole (PCP = 14.9 +/- 31 mmHg and LVEDP = 14.

Electrophysiological profile of bepridil, a new anti-anginal drug with calcium blocking properties.

The electrophysiological effects of intravenously administered bepridil, a new anti-anginal drug with slow calcium current blocking properties, were studied in 20 patients undergoing an endocavitary cardiac exploration for various reasons. Classical techniques of programmed electrical stimulation were used. Bepridil markedly increased the refractory period of the atrium, atrioventricular node and the AH-interval.