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P Bru

Publications and source records attributed to P Bru.

At least 19 recordsLinked to original sources

[Comparative effects of anti-arrhythmia agents on ventricular refractory period and prevention of ventricular tachycardia induced by stimulation].

The efficacy of antiarrhythmic drugs is attributed to their actions on the refractory periods or conduction velocity in the reentry circuit. The aim of this study was to determine the relationship between these factors and the prevention of electrically inducible ventricular tachycardia (VT). Twenty-seven patients with sustained monomorphic postinfarction VT underwent programmed stimulation under basal conditions and after administration of oral Class I antiarrhythmic drugs. The protocol of stimulation consisted of delivering one to three extrastimuli to the right ventricular apex on two basic cycle lengths. Sustained VT was induced in all patients. After the same protocol under antiarrhythmic therapy (1 to 5 tests, average 2.9 +/- 1) sustained VT could not be induced in 12 patients (44%). The effective right ventricular refractory period was significantly increased in patients without inducible VT under treatment (247 +/- 18 versus 302 +/- 26 ms). The increase in the right ventricular effective refractory period in patients with persistence of inducible VT was much less (from 270 +/- 28 to 287 +/- 30 ms). In all patients in whom several antiarrhythmic drugs were tested the right ventricular effective refractory period was higher when the treatment was judged to be effective (299 +/- 27 ms) than ineffective (272 +/- 27, p < 0.02). The prevention of inducible VT by class I antiarrhythmic agents seems therefore to be related to their effect on the ventricular refractory period.

Anti-Arrhythmia Agents

[Doppler echographic evaluation of mitral valve stenosis with atrial fibrillation. Construction of a nomogram].

Doppler echocardiographic evaluation of mitral stenosis is often difficult in patients with atrial fibrillation. Sixteen patients were examined by transthoracic Doppler echocardiography and the relation between the variations in transmitral end diastolic pressure gradient and the length of the corresponding cardiac cycles was analysed. Mitral valve surface area (1.65 +/- 0.73 cm2) was determined by the pressure half-time method. The end diastolic transmitral pressure gradient was calculated from the simplified Bernouilli formula applied to end diastolic mitral flow velocity. In each patient, a linear relationship was observed between the end diastolic mitral gradient and the corresponding RR interval. The slope and intercept of the graph correlated significantly to mitral valve surface area (r = 0.72, p < 0.002 and r = 0.93, p < 0.00001, respectively). Using regression equations describing these correlations, it has been possible to construct a nomogramme indicating mitral valve surface area as a function of mitral end diastolic pressure gradient and the duration of the corresponding RR cycle. This nomogramme facilitates Doppler evaluation of mitral stenosis in atrial fibrillation.

Aged

[Oral propranolol in Wolff-Parkinson-White syndrome. Electrophysiological data].

The effects of oral propranolol were studied in 24 patients with the WPW syndrome. The average daily dose of propranolol was 130 +/- 24 mg administered in 3 doses over a period of 48 to 72 hours. Endocavitary electrophysiological study was performed 2 to 4 hours after the last dose. The effective anterograde refractory periods (EARP) of the accessory and normal pathways were measured before and after propranolol (and, in both studies, before and after isoproterenol). The EARP of the accessory pathway was not affected by the propranolol. However, in the 9 patients in whom its value was less than 270 ms, it increased significantly (p = 0.01). The EARP of the accessory pathway measured after administration of isoproterenol increased significantly in all patients with oral propranolol (p = 0.001). Sustained reciprocating tachycardia could be induced in 19 patients and non-sustained reciprocating tachycardia in 5 other patients during base line electrophysiological study. Oral propranolol prevented the induction of the tachycardias in 18 patients (75%), even after isoproterenol. The shortest R-R interval between two pre-excited complexes in atrial fibrillation increased after propranolol (283 +/- 45 to 343 +/- 95 ms). These results show that oral propranolol increases the EARP of the accessory pathway and the shortest R-R interval between two pre-excited complexes in atrial fibrillation in patients with short anterograde refractory periods of their accessory pathways, and is effective in preventing reciprocating tachycardia. Oral propranolol may be useful and can be used safely in patients with the Wolff-Parkinson-White syndrome.

Administration, Oral

[Value of systematic preventive antibiotherapy in cardiac pacemaker implantation].

The aim of this study was to assess the usefulness of prophylactic antibiotics during insertion of a cardiac pacemaker, in order to avoid infection of exteriorisation of infectious origin. The study involved two groups. One hundred and eight patients made up group I, a control group without the use of prophylactic antibiotics. Group II consisted of 101 patients who were given an intravenous injection of 1 or 2 g of oxacillin before surgery, followed up by four days of oral oxacillin (3 g per day). Serum oxacillin levels at the end of the procedure were 0.37 +/- 0.09 mcg/ml, falling within the range of minimum inhibitory concentrations of methicillin-sensitive staphylococci. In the patients of the control group, followed up for 1 to 36 months (mean 12 +/- 11 months), during the first 2 months there were 2 infections, 4 exteriorisations and one cutaneous erosion over the pacemaker. In addition, one exteriorisation and one infection occurred at 17 and 29 months respectively. In patients with exteriorisation of their pacemaker device, there was nothing to suggest an infection and bacteriological specimens were sterile. No obvious infections nor any cutaneous complications occurred in the patients of group II, with prophylactic antibiotics, followed up for 1 to 21 months (mean 6 +/- 5 months). In conclusion, anti-staphylococcal antibiotic treatment appears not only to be capable of avoiding cardiac pacemaker infections but also of preventing exteriorisation of the pacemaker device, which may be linked to hidden infections. A randomised study is nevertheless necessary to confirm this hypothesis.

Adult

[Complex ventricular extrasystole. Value of programmed electric stimulation for evaluating the risk of sudden death].

A prospective study was carried out from May 1984 to July 1987 to determine the prognostic value of the results of programmed electrical stimulation (PES) in patients with complex ventricular ectopy. The study population comprised 118 patients, 80 with and 38 without apparent underlying cardiac disease. The PES consisted in at most 3 extrastimuli delivered to the right ventricular apex during 2 imposed basal rhythms. Two groups of patients were identified: Group I (n = 35; 29.6%) in which a significant ventricular arrhythmia was induced (sustained ventricular tachycardia (11 cases), non-sustained VT (21 cases) and ventricular fibrillation (3 cases); and Group II (n = 83; 70.3%) in which no significant arrhythmia could be induced. During follow-up (average 28.7 +/- 11.7 months, range 6 to 48 months) there were 10 cardiac deaths, 8 of which occurred suddenly. Sudden death only occurred in patients with cardiac disease and usually with LV ejection fraction of less than 0.40; the prevalence of sudden death in Group I (11.5%) was higher than in Group II (4.8%) but the difference was not statistically significant. The prognosis of patients in Group II was the same as that of the general population. The results of this study suggest that PES enables identification of a subgroup of patients with complex ventricular ectopy in which ventricular tachyarrhythmias cannot be induced and the risk of sudden death is low; the management of patients with inducible ventricular tachyarrhythmias and normal LV function has to be determined case by case.

Adolescent

[Post-traumatic fistula of the left anterior descending coronary artery and left ventricle. Apropos of a new case].

The authors report the case of a 23 year old man who presented with a continuous murmur five years after closed chest trauma. The electrocardiographic and echocardiographic findings indicated previous apical myocardial infarction. The underlying diagnosis was first suggested by continuous wave Doppler which showed systolo-diastolic flow in the septo-apical region directed towards the left ventricle (LV) in diastole. Color Doppler flow studies showed a mosaic pattern opposite a dilated left anterior descending (LAD) artery. These signs of LAD-LV fistula with a single orific were confirmed at coronary arteriography. The patient's previous history was in favour of a traumatic etiology. In the absence of left ventricular failure and myocardial ischaemia by coronary steal, surgery was deferred; Doppler echocardiography would seem to be a good method of following up the fistula and its consequences on left ventricular function. A traumatic left coronary to left ventricular fistula is an extremely rare condition and merits publication. The authors review the literature and describe the physiopathology, diagnosis and therapeutic indications of these fistulae.

Adult

[Wolff-Parkinson-White syndrome. Value of intravenous flecainide for detecting Kent's pathways with short refractory period].

The aim of this study was to assess the value of a non-invasive test in detecting accessory pathways with short anterograde effective refractory periods (AERP) (less than or equal to 270 ms) in patients with the Wolff-Parkinson-White syndrome. An intravenous injection of Flecainide acetate was administered to 19 consecutive patients referred for electrophysiological investigation of a WPW syndrome with permanent pre-excitation of the surface electrocardiogram. The first 8 patients (Group I) received a dose of 1.5 mg/kg over 5 minutes and the following 11 patients (Group II) were given 2 mg/kg in 5 minutes. In Group I, preexcitation disappeared in 3 patients (37.5%) who all had accessory pathways with AERP greater than 270 ms. It persisted in the other 5 patients (62.5%) of whom 4 had AERP less than or equal to 270 ms and 1 an AERP greater than 270 ms (false negative). In Group II, preexcitation disappeared in 8 patients (72.2%) of whom 4 had AERP greater than 270 ms and 4 had AERP less than 270 ms (false positives). Preexcitation persisted in the 3 other patients (27.3%); the AERP was less than or equal to 270 ms in 2 patients and greater than 270 ms in the other patients. These results suggest that intravenous Flecainide acetate at the dose of 1.5 mg/kg could be useful in differentiating WPW syndromes with long refractory periods (greater than 270 ms) from those with short refractory periods (less than or equal to 270 ms) with a satisfactory sensitivity and specificity, and that further studies on larger numbers of patients are required to confirm this hypothesis.

Adolescent

[Electrophysiologic evaluation and follow-up of patients with a syncopal episode of unknown origin].

The etiology of syncope of presumed cardiac origin can be determined by clinical and electrocardiographic examination with Holter monitoring in about 50 per cent of cases. The aim of this study was to review the data of electrophysiological investigation and the outcome of the patients in whom a cardiac pacemaker was eventually implanted, in those cases in whom the initial work-up had been negative. Ninety four patients, all of whom underwent standardised electrophysiological investigation, were included. The results of the investigations enabled us to identify three groups of patients: Group I: patients in whom the criteria did not suggest a cardiac origin of syncope; Group II: with criteria possibly suggesting a cardiac origin and Group III in which the criteria were strongly suggestive of a cardiac origin. A cardiac pacemaker was implanted systematically for AV block in Group III; on the other hand, this was very rare (only 1 patient) in Group I, and the indication in Group II depended on age and the history of recurrent syncope. Ninety patients (96%) were followed up for an average of 39.3 +/- 15.3 months. There was a very low incidence of recurrent syncope irrespective of the original classification, so confirming the value of electrophysiological investigations for cardiac pacemaker implantation in this type of patients. In addition, negative electrophysiological investigations allowed identification of a group of patients with a low mortality and low risk of recurrent syncope.

Aged

[Septal rupture repaired in the acute stage of myocardial infarction. Clinical, hemodynamic and angio-coronarography findings in the evaluation of surgical risk].

Between 1977 and 1987, 27 consecutive patients (16 men, 11 women, mean age 66 years, range 54 to 75 years) with ventricular septal rupture complicating acute myocardial infarction underwent surgical repair. The purpose of this retrospective study was to analyse the post-operative mortality factors from clinical, haemodynamic and operative data in all patients and also from coronary angiographic data in 23/27 patients whose haemodynamic status allowed this type of exploration. Seventeen patients (63 p. 100) died during the first post-operative month, 10 survived and were discharged. Factors that influenced the prognosis were: (1) inferiorly-located necrosis associated with a 75 p. 100 mortality rate (9 out of 12 patients), as opposed to 53 p. 100 (8 out of 15 patients) with anterior necrosis; (2) right ventricular dysfunction, observed in 83 p. 100 of patients with inferior necrosis and 53 p. 100 with anterior necrosis, which was responsible for 7 out of 9 deaths in the inferior necrosis subgroup and contributed to 3 out of 8 deaths in the anterior necrosis subgroup; this established a cause-effect relationship between right ventricular function and the overmortality of patients with inferior necrosis; (3) independently of the haemodynamic status, two- and three-vessel lesions (56 p. 100 of all lesions) which had an 84 p. 100 mortality rate as opposed to 40 p. 100 with one-vessel lesions; (4) the presence of a state of shock which was associated with a 78 p. 100 mortality rate as opposed to 55 p. 100 in patients without shock. We conclude that when permitted by the patient's haemodynamic status coronary angiography should be part of the pre-operative evaluation to assess the operative risk and guide the surgical procedure.

Acute Disease

[Arrhythmogenic effects of antidepressive agents demonstrated by programmed ventricular pacing].

Tricyclic antidepressants and phenothiazines have been blamed for increasing the incidence of sudden death. One of their known mechanisms of action in such cases is to induce torsades de pointes by a so-called "quinidine-like" effect. We report the case of a female patient who was rescued from an episode of cardiac arrest which occurred two months after a myocardial infarction. Right ventricular programmed pacing strongly suggested an arrhythmogenic effect to the antidepressant the patient was receiving. This type of treatment seems to be capable of facilitating the induction of a monomorphous ventricular tachycardia which may degenerate into ventricular fibrillation.

Antidepressive Agents, Tricyclic

[Cardioversion by internal electric shock of permanent atrial fibrillation].

A new technique for cardioversion of chronic atrial fibrillation was used in 17 patients whose arrhythmia had resisted all attempts at electrical and pharmacologycal cardioversion. Atrial fibrillation was badly tolerated by all patients despite digitalis administered alone (8 patients) or combined with amiodarone (9 patients). Twelve patients had left atrial dilatation at echocardiography. The 200, 300 or 400 joule electrical shock was delivered between the proximal pole of a quadripolar catheter (cathode) and a back plate (anode). The catheter was positioned at the His bundle recording site then withdrawn into the right atrium. The internal shock restored sinus rhythm in 15 patients (88 p. 100). Transient atrioventricular block (3-315 sec) was observed in 8 patients. Eleven patients were discharged in sinus rhythm. In 4 patients, the atrial fibrillation recurred on day 8 and after 2, 4 and 9 months. A second shock was attempted in two patients and succeeded in one. After a mean follow-up period of 14.8 +/- 8 months (range 2 to 25 months), 8 of the 11 patients successfully cardioverted (72 p. 100) or of the attempted reductions (47 p. 100) were in sinus rhythm. The remaining 9 patients were treated with antiarrhythmic drugs (n = 5) or by his bundle catheter ablation (n = 4). High energy internal shock therefore seems to be an interesting treatment in patients with permanent atrial fibrillation after failure of external electric shock. It enabled 13 of the 17 patients in this series to avoid His bundle catheter ablation indicated by the quasi-impossibility to control the atrial rate and associated symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

High energy transcatheter cardioversion of chronic atrial fibrillation.

A new technique of internal transcatheter cardioversion of chronic atrial fibrillation using high energy shocks (200 to 300 joules) was performed in 10 patients. In all patients, external cardioversion (300 to 400 joules) and pharmacologic therapy failed to restore sinus rhythm. Atrial fibrillation was poorly tolerated despite digitalis therapy alone (five patients) or in combination with amiodarone (five patients). High energy transcatheter cardioversion was performed by pulling back the atrioventricular (AV) junction catheter just inferior to the site of His bundle recording and delivering the shock between a proximal electrode (catheter) and backplate (anode). High energy internal cardioversion restored sinus rhythm in 9 of the 10 patients. However, atrial fibrillation recurred within 3 min in two of them; in the remaining patient, the procedure failed to terminate atrial fibrillation. The only complication observed was transient (3 to 315 s) heart block immediately after shock delivery and this was treated by temporary pacing. Seven patients had sinus rhythm on discharge from the hospital, but in three, recurrent atrial fibrillation appeared at 8 days and 2 and 4 months, respectively. A second attempt of transcatheter cardioversion was performed in two patients and was successful in one patient. With a follow-up ranging from 2 to 11 months, five patients continued to have sinus rhythm. These preliminary results suggest that high energy internal cardioversion may be an alternative to AV junction ablation in selected patients with poorly tolerated chronic atrial fibrillation in whom external cardioversion was unsuccessful.

Adult

Long-term follow-up of atrioventricular junctional transcatheter electrical ablation.

Complete data concerning long-term results of transcatheter electrical ablation of the atrioventricular junction is not available. At the request of the French Cardiac Arrhythmia Working group we undertook an inquiry in October 1983. All centers potentially able to perform such procedures were asked to report their experience. Eight centers have performed one case or more, over a period of 3 years, for a total of 91 patients. The mean follow-up completed in all patients in April 1986 was 12 +/- 10 months. The procedure was indicated for a supraventricular arrhythmia resistant to a mean of 3.9 +/- 1.3 classes of antiarrhythmic agents. Atrial flutter or fibrillation in 54 (59%) and atrioventricular nodal reentry in 17 (18%) were the most common arrhythmias. A mean of 2.6 +/- 2.3 electrical shocks (range 1-14 shocks) with a stored energy of 130-400 joules was delivered during 1-5 sessions. Complete heart block was obtained in 83 patients and persisted at the time of discharge from the hospital in 46 patients (50.5%). The immediate complication (within 24 hours after the procedure) included ventricular fibrillation successfully converted (one patient) and nonsustained ventricular tachycardia (three patients). Late complications included one death 3 days after the procedure, in a patient in whom sustained ventricular tachycardia was documented, nonsustained ventricular tachycardia in two patients, sepsis in three patients and pericardial effusion in one patient. At the time of the follow-up, there were three additional deaths related to sepsis due to pacemaker pocket infection in one patient and to preexisting congestive heart failure in two patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Electrocardiographic characteristics of the escape rhythm in transient complete atrioventricular block induced by transcatheter electrical ablation of the atrioventricular junction.

The electrocardiographic characteristics of spontaneous escape rhythm during complete heart block induced by transcatheter ablation of the atrioventricular junction was prospectively studied in 21 patients by periodically interrupting temporary pacing. The data derived from 13 of these 21 patients, in whom conduction recurred after the procedure, were analyzed. An escape rhythm was present in 12 patients 8.2 +/- 5.8 minutes after shock delivery at a cycle length of 1985 +/- 974 ms. The escape QRS had a configuration of right bundle branch block with left axis deviation in 9 patients, of right bundle branch block with normal axis in 1, of left bundle branch block with left axis deviation in 1, and 2 distinct morphologies in the remaining patient. After resumption of conduction, the conducted complexes were identical to the escape complexes in six patients, different only in axis in four patients, and different in morphology in two patients. This suggests that in the majority of patients the escape rhythm seen during transient heart block, induced by transcatheter ablation of the atrioventricular junction, presents a right bundle branch morphology with or without a left axis deviation, and most likely originates from an area above, or close to, the site of the anatomical damage.

Adult

[Cardiomuscular lysosomal glycogenosis in adults without known enzyme deficiency. A cause of familial myocardiopathy and lysosomal glycogen overload with normal acid maltase].

An unusual form of familial myocardiopathy is reported. The disease affected siblings entering adulthood and presented as subclinical skeletal muscle and patent cardiac muscle lesions. Quadriceps muscle biopsy performed in a young man who subsequently died of cardial failure revealed excessive lysosomal glycogen storage, as in type II glycogenosis, but biochemistry showed normal enzymatic activity. In a sister with hypertrophic myocardiopathy only leucocytes were examined; they also showed normal enzymatic activity. Other clinical manifestations of this form of familial myocardiopathy are hypoglycaemia and moderate skeletal muscle involvement. At histology, the image is that of Pompe's disease, but the acid maltase level is normal. The condition seems to be transmitted as an autosomal dominant trait.

Adult

[Wolff-Parkinson-White syndrome. Outcome of patients treated with anti-arrhythmia agents from data of electrophysiological examinations].

Seventy-two consecutive patients with electrocardiographic evidence of Wolff-Parkinson-White syndrome underwent electrophysiological study (EPS). Fifty-five of these patients (76 p. 100) had episodes of tachycardia, 11 experienced palpitations or syncopes and 6 were asymptomatic. The decision to prescribe an antiarrhythmic agent was reached on the basis of the patients' symptoms and EPS data. One patient was treated by surgery before the medical treatment was tried; 17 patients were discharged without treatment, 4 were discharged with an episodic and 50 with a preventive antiarrhythmic treatment. Among these 50 patients, 46 (92 p. 100) could be followed up for a mean period of 45.7 +/- 28 months. One died of lung cancer; 43 presented with spontaneous episodes of tachycardia, 4 were able to discontinue treatment at the end of the follow-up period since they had very few symptoms and 2 were lost sight of. Among the 37 patients under antiarrhythmic treatment followed up, 29 (78 p. 100) are well controlled, while 8 (22 p. 100) still present with episodes of tachycardia. A tachycardia-reducing pacemaker was implanted in 5 of these 8 patients. It therefore appears that 78 p. 100 of patients presenting with spontaneous episodes of tachycardia associated with WPW syndrome can be controlled with an antiarrhythmic treatment. This result was obtained after trying at least two types of antiarrhythmic agents in 86 p. 100 of the cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

[Cardiac Doppler in the selection of patients for aortic valvuloplasty. Comparison with data of phonomecanograms].

Between December 1986 and August 1987, 34 patients referred for aortic valvuloplasty, undergo before catheterization an ultrasonocardiography with continuous and pulsed Doppler study and a phonocardiography for 22 of them. They all present functional and physical signs of aortic stenosis. The cardiac Doppler enables a positive diagnosis in all patients, while the phonocardiography recordings fail to recognize a tight aortic stenosis. On the other hand, the Doppler enables a diagnosis of severity well correlated with the catheterization (r = 0.88 for maximum instantaneous gradients) in 30 patients: in four patients, the correlation could not be calculated because of technical problems related to the catheterization (2 patients) or the ultrasonic examination (2 patients). From this study, it results that the cardiac Doppler may perfectly select patients who are to undergo an aortic valvuloplasty, unlike phonocardiography.

Adult