PubMed Health⌕ Search

Biomedical subjects

D Beurrier

Publications and source records attributed to D Beurrier.

At least 73 records · Page 4Linked to original sources

[Syncopes associated with mitral valve prolapse. Mechanisms].

Prolapsed mitral valve prolapse (PMV) is classically associated with disorders of ventricular excitability whose significance is unclear. However, syncope can suggest the possibility of a serious ventricular arrhythmia. The objective of this study was to try to identify the mechanisms of dizziness and syncope associated with PMV. We report the results of programmed atrial and ventricular stimulation performed under baseline conditions and after administration of Isuprel in 56 patients with PMV: 27 patients had a history of presyncope or syncope (group I), 14 had spontaneous atrial or supraventricular tachycardias without dizziness or syncope (group II) and 15 were asymptomatic and investigated for VEBs or conduction disorders (group III). The following results were obtained: In group I, 6 patients experienced sustained inducible ventricular tachycardia (VT); an atrial tachycardia (atrial tachycardia and/or atrial fibrillation) (AT) was also induced in 5 of them. In another 19 patients, a supraventricular tachycardia (SVT) and/or AT was induced. A total of 24 atrial or junctional tachycardias were triggered in this group. In group II, AT and/or SVT were reproduced in 13 out of 14 cases (93%). In group III, AT was triggered in 3 patients (20%). SVT were induced by Isuprel while AT were triggered prior to administration of Isuprel, under baseline conditions, and 3 of them were reproduced during vagal manoeuvres. A ventricular arrhythmogenic effect was observed in two cases in group II while taking class I antiarrhythmics. In conclusion, spontaneous AT and SVT of PMV are easily inducible with a sensitivity of 93%, but are difficult to induce in asymptomatic subjects. The high incidence of TA and SVT in the case of unexplained presyncope in subjects without documented tachycardia therefore appears to be suggestive of a relationship between these presyncopes and AT or SVT. However, the search for VT should take precedence. SVT appear to be catecholaminergic while AT tend to be vagal.

Adolescent↗

Radiofrequency catheter ablation of a nodoventricular Mahaim tract.

We report the case of a patient with both a left bundle branch block-preexcited tachycardia using a Mahaim bundle and a tachycardia exhibiting a left bundle branch pattern without preexcited complexes related to an AV nodal reentrant tachycardia. Successful ablation of the nodoventricular tract was obtained in the posteroseptal location in the AV node region. The pattern of Wolff-Parkinson-White (WPW) syndrome and both forms of tachycardia disappeared.

Atrioventricular Node↗

Programmed ventricular stimulation in survivors of acute myocardial infarction: long-term follow-up.

The prognostic significance of ventricular tachyarrhythmias induced by programmed ventricular stimulation was evaluated in 492 consecutive survivors of acute myocardial infarction (AMI). Holter monitoring, signal-averaged electrocardiogram (ECG) and measurement of left ventricular ejection fraction (EF) were also performed. The protocol used up to 3 extrastimuli. Sustained monomorphic ventricular tachycardia (VT) < 270 beats/min, > 270 beats/min (ventricular flutter) (VFI), and ventricular fibrillation (VF) were induced in 99, 66 and 52 patients, respectively. Long term follow-up (mean 3.7 +/- 2.2 years) showed that most episodes of VT occurred during the first months following AMI (n = 14), but some patients (n = 6) could develop VT as late as 4 years after AMI. Sudden death (SD) (n = 22) always occurred during the first year following AMI. Multivariate analysis demonstrated that EF < 30% and induction of a VT < 270 beats/min were the only predictors for total cardiac death (P < 0.001). EF < 30%, induction of a VT < 270 beats/min and also of VFI (P < 0.05) were predictors for VT and SD: the risk was 4% in patients without inducible VT, 12% in those with inducible VF1, and 21% in those with inducible VT < 270 beats/min. In conclusion, induction of a sustained monomorphic VT < 270 beats/min or > 270 beats/min is a predictor of arrhythmic events during the first year as well as 4 years after myocardial infarction. However the risk of arrhythmic sudden death decreases after the first year, while the risk of VT persists. Because of the low positive predictive value of programmed stimulation (respectively 21% and 12% for the induction of a sustained VT and VFI), we recommended the indication of programmed stimulation in only the patients with one abnormal non-invasive investigation.

Actuarial Analysis↗

Long-term prediction of major ischemic events by exercise thallium-201 single-photon emission computed tomography. Incremental prognostic value compared with clinical, exercise testing, catheterization and radionuclide angiographic data.

OBJECTIVES: This study sought to evaluate the prognostic role of exercise thallium-201 (Tl-201) single-photon emission computed tomography (SPECT) in patients with known or suspected coronary artery disease. BACKGROUND: Compared with planar Tl-201 scintigraphy, Tl-201 SPECT allows enhanced assessment of myocardial perfusion abnormalities. However, the long-term prognostic value of exercise Tl-201 SPECT has not been ascertained and compared with that of other techniques of investigation. METHODS: Predictors of ischemic events were sought in 217 patients with known or suspected coronary artery disease who underwent exercise Tl-201 SPECT, coronary angiography and rest radionuclide angiography and who initially received medical therapy. Predictive values were determined using Cox proportional hazards regression models. RESULTS: During a mean (+/- SD) follow-up period of 70 +/- 19 months, 29 patients had a major ischemic event (cardiac death or myocardial infarction). Total extent of exercise defects was the best independent predictor by Tl-201 SPECT of major events (p < 0.001) and provided additional prognostic information compared with clinical, exercise testing and catheterization variables (p < 0.02). Extent of reversible Tl-201 SPECT perfusion defects provided additional prognostic information compared with extent of irreversible defects (p < 0.001) and was the sole Tl-201 SPECT variable providing additional prognostic information compared with radionuclide left ventricular ejection fraction (p < 0.02). CONCLUSIONS: Total extent of exercise Tl-201 SPECT defects is a powerful long-term predictor of major ischemic events that enhances the prediction provided by clinical, exercise testing and coronary angiographic data. In view of its prognostic significance, extent of reversible Tl-201 SPECT defects might provide original information about improving prognosis by coronary revascularization.

Age Factors↗

Changes in spontaneous sinus node rate after ventricular pacing as an estimate of autonomic tone: clinical applications.

Rapid ventricular pacing (VP) reproduces neurohumoral variations associated with ventricular tachycardia. This study was set up to analyse the mechanisms that cause changes in sinus heart rate after rapid VP and to find the clinical factors that adapt sinus heart rate to VP, and the clinical value of the method. Rapid VP was performed in 356 patients aged 15 to 86 years, in increments of 10 beats, at progressively faster rates every 10 s up to 200 beats.min-1. Group I comprised 122 patients with no underlying heart disease; group II comprised 234 patients with an underlying heart disease. The sinus heart rate (HR) was initially accelerated (SR1), in comparison with the basal sinus HR, for 2 to 5 s (90.5 beats.min +/- 21 vs 71 +/- 19 in group I, 89.5 +/- 26 vs 76 +/- 16 in group II). Five seconds later, there was a decrease in HR (SR2) which was slower than the basal HR (62 beats.min +/- 22 in group I, 75 +/- 15 in group II). The variations in HR, defined as SR1-SR2/SR1, were significantly higher in group I than group II: 31 +/- 18% vs 19 +/- 15%, (P < 0.001). With the injection of 2 mg atropine in 14 group I patients the variations in HR were suppressed after ventricular pacing. When oral beta-blockers were administered to 21 group I patients, there were still significant changes in HR. The changes in HR were reproducible during electrophysiological study.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Transluminal coronary angioplasty in patients with left ventricular dysfunction; immediate and long term results].

Transluminal coronary angioplasty is increasingly performed in patients with left ventricular dysfunction. However, there is little data available concerning the outcome of these patients. The aim of this retrospective study was to assess the immediate and long-term results in 90 patients (76 men and 14 women) with left ventricular ejection fractions < or = 35% (average 29 +/- 5%) undergoing angioplasty between 1980 and December 1992. Eighty-seven patients (96%) had a history of infarction, 27 (30%) had already at least one episode of left ventricular failure and 34 (38%) had unstable angina at the time of angioplasty. The coronary disease was usually multi-vessel. A total of 118 lesions were dilated with a primary success rate of 77% (91/118): 86% (82/95) in non-occlusive stenoses and 39% (9/23) in complete obstructions. The total success rate per procedure was 72% (65/90) with a hospital mortality rate of 5.5% (5 cases). The mean follow-up period was 53 +/- 47 months. Twelve patients died during this period and two were lost to follow-up. The total and cardiovascular mortality at the end of the study was 19% (17/88). Eight of the 71 survivors underwent another revascularisation procedure (4 bypasses and 4 angioplasties); 21 (29%) have stable angina, 50 (71%) have no anginal pain and 61 (86%) have antianginal treatment. The probability of survival at one and four years was 81 +/- 4% and 79 +/- 5%, respectively. A multivariate analysis using the Cox model showed three independent prognostic factors for long-term mortality: triple coronary vessel disease, the best predictive factor, left ventricular ejection fraction and female gender.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[Is the transesophageal approach preferable to endocavitary approach in the evaluation of Wolff-Parkinson-White syndrome?].

Now that the radical treatment of the Wolff-Parkinson-White syndrome is established, it is essential to evaluate the prognosis of this condition accurately. Initiation of atrial fibrillation is one of the factors which influence the prognosis. The aim of this study was to compare the results of electrophysiological studies performed by the endocavitary and transoesophageal approaches in the measurement of the initiation of atrial fibrillation. Twenty-six patients with a patent Wolff-Parkinson-White syndrome were studied by the two methods with a similar protocol: incremental atrial pacing to the Wenckebach point, programmed atrial stimulation using up to two extrastimuli, repeated with an infusion of 20 to 30 ug of isoproterenol. Sixteen patients had reciprocating nodal tachycardia or were asymptomatic (group I) and the other 10 had spontaneous atrial fibrillation (group II). In group I, atrial fibrillation was induced in 9 cases (56%) by the endocavitary and in two cases (12.5%) by the transoesophageal method. In group II, spontaneous atrial fibrillation was reproduced in all cases by the endocavitary and transoesophageal protocols. None of the patients in group I developed atrial fibrillation during follow-up (average 2 years +/- 9 months). The authors observe that all spontaneous atrial fibrillation of the Wolff-Parkinson-White syndrome can be triggered by oesophageal stimulation. The prevalence of atrial fibrillation was overestimated by endocavitary studies in asymptomatic or paucisymptomatic patients. The assessment of atrial vulnerability of a Wolff-Parkinson-White syndrome may therefore be performed by transoesophageal electro-physiological studies.

Adolescent↗

[Changes in blood cholesterol levels over a 10-year period; value of a single sample for predicting future blood cholesterol levels].

The aim of this study was to report the serum cholesterol changes over a 10 year period in 12,238 subjects aged 4 to 64 years (mean 28 +/- 14 years) based on 3 health check-ups at an average of 5.5 yearly intervals between 1973 and 1989, and to determine the value of a single sample for predicting the serum cholesterol level at 5 and 10 years, and the influence of blood pressure and Quetelet index on this predictability. After identification of the influencing factors, the different variables were adjusted using a step-by-step regression analysis. The correlation coefficients calculated between the adjusted cholesterol level at the first examination and that measured at 5 and 10 years, were all significant (0.38 to 0.59) and varied with age at the time of the first examination and gender. The positive predictive value of having a cholesterol level higher than the 90th centile at 5 and 10 years when it was already higher than this value at the first examination varied from 26 to 46% respectively with respect to the subgroups. The sensitivity of the test was 25 to 48%. The negative predictive value and specificity were 93 to 95%. The lowering of this threshold to the 80th centile increased the positive predictive value from 35 to 45% and decreased the specificity from 94 to 87% for the whole population. When the first two sampling results, five years apart, were taken into consideration simultaneously, the predictive value of having a raised cholesterol level at 10 years increased from 35 to 61%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Ablation of the bundle of His through a patent foramen ovale, by approach from the left side].

The authors report the case of a 60-year-old male patient in whom resection of the bundle of His via a right-sided approach to treat permanent very rapid atrial fibrillation was attempted, but failed. The bundle of His tissue was resected very easily on the left side due to the presence of a patent foramen ovale, which also avoided the risks of the left catheterism in this patient.

Atrial Fibrillation↗

[Should a signal-averaged electrocardiogram be requested in the evaluation of malaise and syncope?].

In order to determine whether signal-averaged electrocardiography was useful in the diagnosis of syncopal ventricular tachycardia, 244 subjects with malaise or unexplained syncope without documented ventricular tachycardia underwent endocavitary electrophysiological study and signal-averaged electrocardiography with a 25 Hz bandpass filter. Ninety-three patients had no apparent cardiac disease whereas 151 patients had cardiac problems. ventricular tachycardia was induced in 91 patients. Fifty-two of them (57%) had ventricular late potentials. Twenty-two patients without inducible ventricular tachycardia also had late potentials (14%). The diagnostic value of signal-averaged electrocardiography depended on the cardiac disease: in the absence of cardiac disease, its sensitivity was poor (31%) but the specificity was excellent (96%). In the presence of cardiac disease, the sensitivity improved (63%) but the specificity was not as good (67%). The lack of sensitivity in the group with cardiac disease generally concerned subjects with inducible rapid ventricular tachycardia. The authors conclude that signal-averaged electrocardiography should not be requested in the investigation of unexplained syncope in subjects without cardiac disease to demonstrate abnormal ventricular excitability which is very rate in these subjects. On the other hand it is more valuable in those with underlying cardiac disease although inducible rapid ventricular tachycardia may still escape detection.

Adolescent↗

[Influence of the duration of myocardial infarction on QRS duration measured by signal averaged electrocardiography].

The aim of this study was to determine the influence of the chronicity of myocardial infarction on QRS duration. The signal-averaged electrocardiogram (SA ECG) was recorded with a 40 Hz filter in 239 patients with a history of myocardial infarction. The infarction was recent (up to 6 weeks) in 105 patients (group A) and chronic (> 1 year) in the other 134 cases (group B). In group A, 35 patients had inductible sustained ventricular tachycardia (VT) at less than 270/mn; 40 had negative electrophysiological investigations and 30 had inducible ventricular flutter or fibrillation (VF). In group B, 58 had inducible VT, 54 had negative investigations and 22 had inducible VF. The three SA ECG parameters (QRS duration, amplitude of RMS 40 and duration of LAS) differed significantly in subjects with VT with respect to those with negative investigations and inducible VF, irrespective of the chronicity of infarction. On the other hand, only QRS duration differentiated patients with recent infarction from those with chronic infarction, irrespective of the results of programmed pacing, QRS duration being longer in group B. The best diagnostic value of QRS duration for identifying subjects with VT < 270/mn and negative investigations was 110 ms in group A and 120 ms in group B (sensitivity 46% and 77.5% respectively). In chronic infarction, the increase in QRS duration was significantly correlated to the decrease in left ventricular ejection fraction. The authors conclude that the criteria of abnormality of QRS duration are dependent on the chronicity of myocardial infarction. Although a duration of 110 ms is abnormal in the early post-infarction period, after a period of one year, a value of 120 ms should be considered to be pathological, especially when the sequellae of infarction are important.

Adult↗

[Treatment after myocardial infarction].

Advances in the treatment of the acute phase of myocardial infarction have lead to the need for adequate secondary treatment. beta-blockers have been largely demonstrated to be effective antianginal agents, acting on three determining factors: heart rate, systemic blood pressure and myocardial contractility. Used in secondary prevent treatment, beta-blockers lead to significant improvement in global post-myocardial infarction mortality, reduced from 9.4 to 7.6% and in reinfarction rates, reduced from 7.5 to 5.6%. Prescription of beta-blockers beyond the acute phase is an essential part of secondary prevention. For calcium antagonists however, there is no evidence of improved prognosis after myocardial infarction. There is no improvement in mortality or reinfarction rates. Class I antiarrhythmic drugs are not indicated as systematic treatment after myocardial infarction. Angiotensin converting enzyme inhibitors can reduce long-term mortality and late occurrence of congestive heart failure, particularly in patients with moderate to severe left ventricular dysfunction. Among the anti-thrombotic drugs, oral anticoagulants seem to offer no clear advantage over aspirin. Large trials of anti-arrhythmic agents have failed to demonstrate any clinical benefit in asymptomatic patients with ventricular ectopic beats, and the results of secondary prevention trials using amiodarone are still awaited. Myocardial revascularization using coronary bypass surgery or percutaneous transluminal coronary angioplasty should be proposed mainly in symptomatic patients or in subsets of patients with multi-vessel disease and altered left ventricular function. Finally, rehabilitation measures should be aimed at correcting cardiovascular risk factors and improving physical fitness.

Adrenergic beta-Antagonists↗

[Changes in heart rate after ventricular stimulation; correlations with vagal tone].

The authors report a new method of studying the autonomic nervous system, especially vagal tone, during endocavitary electrophysiological studies. After termination of fixed ventricular pacing at incremental rates to 200/min, an initial acceleration of the heart rate is observed followed about 5 seconds later by a sudden slowing. This phenomenon was studied in 278 patients. Ninety seven patients had no cardiac disease: the variation in heart rate was 33 +/- 18%. In the 181 other patients with cardiac disease (ejection fraction 35 +/- 16%) the variation was only 21 +/- 16% (p < 0.01). When the ejection fraction was less than 30%, the variation was only 13 +/- 4%. When the heart rate variation was less than 10%, the prognosis was poor because, of the 48 patients with this sign, 13 died, whereas there were only 2 deaths in the 133 other patients with cardiac disease and preserved adaptation. In 14 patients without cardiac disease the injection of 2 mg of atropine suppressed all adaptation of the heart rate, whilst in 18 other patients, oral betablockers reduced the variation but it persisted to a significant degree. The authors conclude that the adaptation of the heart rate after rapid ventricular stimulation is probably a reflection of vagal tone and may be used to assess the prognosis of subjects undergoing electrophysiological investigations.

Adolescent↗

[Value of permanent cardiac pacing in hypertrophic and obstructive cardiomyopathies resistant to medical treatment].

The authors report their experience of long-term dual-chamber pacing in the treatment of hypertrophic and obstructive cardiomyopathy. Between August 1990 and March 1993, 16 patients (8 men, average age 53.5 +/- 18.9 years, range 21 and 79 years) with symptomatic hypertrophic obstructive cardiomyopathy resistant to medical therapy underwent electrophysiological investigation to assess atrioventricular conduction and the effects of temporary atrioventricular pacing on the intraventricular pressure gradient before implantation of a dual-chamber pacing system. The decision to implant was taken if the endocavitary studies showed severe atrioventricular conduction defects and/or if temporary pacing reduced the systolic pressure gradient by more than 30%. Temporary dual-chamber pacing led to a decrease of 48% of the systolic pressure gradient from 78.6 +/- 21.3 to 40.1 +/- 23.6 mmHg (p < 0.0005), a regression observed in 15 of the 16 patients. After an average follow-up period of 18.7 +/- 9.5 months (range 6 and 37 months), all 15 patients who received a dual-chamber pacing system were alive and were clinically improved. The systolic pressure gradient continued to decrease during the follow-up period (24.4 +/- 17.2 mmHg at the 6th month compared with 36.5 +/- 18.6 mmHg at the time of implantation; p = 0.014). The clinical improvement was dependent on careful adjustment of the atrioventricular delay which was programmed at relatively short values (65.6 +/- 14 ms, range 47 and 75 ms) to obtain permanent right ventricular capture. The authors conclude that dual-chamber pacing is an effective means of treating symptomatic hypertrophic obstructive cardiomyopathy resistant to medical therapy, even in the absence of preexisting conduction defects.

Adult↗

Criteria of QRS duration in relationship to the age of myocardial infarction.

QRS duration is one of the most important factors analysed by signal-averaged electrocardiography. The purpose of the study was to compare three methods of QRS duration measurement (conventional 12 lead ECG, Frank vectorcardiogram [VCG] and signal-averaged electrocardiography [SA ECG]) and to look for the factors associated with changes in QRS duration. The recordings were made at the same time in 113 consecutive patients with a PC-based system ECG and VCG (Cardionics) and high resolution ECG (Cardionics) based on methods described by Simson. Patients with bundle branch block were excluded. All patients had presented a myocardial infarction and were studied either for spontaneous ventricular arrhythmias or systematically, early after infarction (3 to 6 weeks) in 45 patients (group I) or late after infarction (> 9 months) in 68 patients (group II). 21 patients of group I had inducible sustained monomorphic ventricular tachycardia (VT) (group I) and 24 did not (group Ib). 36 patients of group II had inducible VT (group IIa) and 32 did not (group IIb). The comparison of the 3 methods for the evaluation of QRS duration shows that the QRS duration was related to 2 factors, the inducibility of VT, and the age of the infarction: 1. QRS duration was prolonged in patients with inducible sustained VT in groups I and II. 2. QRS duration was longer in patients of group I than in group II. A value > 110 ms in group I was pathological, while a value > 120 ms was required ingroup II to be considered as pathological.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Usefulness of exercise SPECT-thallium to detect asymptomatic restenosis in patients who had angina before coronary angioplasty.

The usefulness of exercise single photon emission computed tomography (SPECT)-thallium for detecting asymptomatic restenosis was assessed prospectively in 62 patients with angina before angioplasty, who underwent < or = 6-month re-angiography and exercise SPECT-thallium imaging. Among patients with restenosis, nine had recurrence of angina but eight did not. These two subgroups had equivalent percentages of restenosis (71 +/- 16% vs 64 +/- 16%, NS) and extent of reversible thallium defects (2.8 +/- 1.7 vs 4.1 +/- 2.6, NS), and both subgroups had poorer hemodynamic responses to exercise compared with patients without restenosis (maximal) rate-pressure product [X 100], 258 +/- 54 and 239 +/- 33 vs 302 +/- 61; p < 0.05 and p < 0.01, respectively). Exercise testing detected fewer patients with restenosis compared to exercise SPECT-thallium imaging, especially among asymptomatic patients (25% vs 100%, p < 0.005). Asymptomatic restenosis occurs frequently, induces an amount of stress ischemia equivalent to that of symptomatic restenosis, and is efficiently detected by exercise SPECT-thallium with rest-reinjection but not by exercise testing.

Aged↗

Effect of isoproterenol on serum potassium and magnesium.

Some ventricular arrhythmias can be related to a decrease in the level of potassium (K) and/or magnesium (Mg). Because adrenergic stimulation decreases serum K+ and Mg++, we decided to investigate the effects of a beta-receptor agonist, isoproterenol, on serum K+ and Mg++, and their consequences on the induction of tachycardia. Programmed atrial and ventricular stimulation was performed in 95 patients before and during infusion of 1.6 micrograms.ml-1 of isoproterenol. During isoproterenol infusion, 61 patients had no inducible tachycardias (group I) and 34 had inducible sustained tachycardias (group II): 16 of them (group IIA) had inducible sustained supraventricular tachyarrhythmias and 18 (group IIB) had inducible sustained ventricular tachycardia. Serum K+ and Mg++ were measured at the end of stimulation in the control state and during isoproterenol infusion. The basal values in groups I and II did not differ (3.8 +/- 0.38 vs 3.86 +/- 0.39 mEq.l-1 for K+, and 20.18 +/- 2.68 vs 19.83 +/- 1.63 mg.l-1 for Mg++). Isoproterenol infusion induced a significant (P < 0.001) hypokalaemia in all groups and a decrease in serum Mg in group II: there was a significant decrease in serum Mg++ (P < 0.05) in group IIA (19.55 +/- 1.7 vs 20.4 +/- 4.6). The decrease in serum Mg++ in group IIB (18.9 +/- 1.55 vs 19.32 +/- 1.63) was not significant. However the serum Mg++ level during isoproterenol infusion was significantly lower in group IIB than in group I. In conclusion, the infusion of isoproterenol was responsible for a significant hypokalaemia, which did not explain the induction of tachycardia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗