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J Lekieffre

Publications and source records attributed to J Lekieffre.

At least 19 recordsLinked to original sources
PubMed1992

Signal-averaged electrocardiography and detection of heart transplant rejection: comparison of time and frequency domain analyses.

To evaluate the role of the signal-averaged electrocardiogram (ECG) in the detection of heart transplant rejection, findings on 277 ECGs were compared with those in 218 endomyocardial biopsy specimens in 25 patients followed up for a median duration of 5.2 months (range 7 days to 17.5 months). Signal-averaged ECGs obtained at intervals of 16.4 +/- 22.3 days were analyzed in the time domain before and after high pass filtering at 25 and 70 Hz. Frequency domain analysis was performed with use of a fast Fourier transform algorithm. Sixteen severe rejection episodes requiring treatment were observed. These episodes induced significant decreases in peak and root-mean-square voltages of both filtered and unfiltered QRS complexes, as well as in the total spectral area. Conversely, QRS duration and 50- to 250-Hz or 70- to 110-Hz spectral areas were not significantly altered. In 14 cases mild rejection episodes were observed that did not significantly alter any of the variables studied. The root-mean-square voltage of the 70-Hz high pass filtered QRS complex was found to be the most accurate variable in detecting rejection. Moreover, this variable was also the most reproducible in 10 healthy control subjects. The optimal rejection criterion was defined as an 11% decrease in voltage between two consecutive recordings. It provided 87.5% sensitivity with 78.4% specificity. In conclusion, the signal-averaged ECG is helpful in the management of heart transplant rejection. Frequency domain analysis of the QRS complex does not increase the accuracy of the technique compared with the time domain approach.

Adult↗
PubMed1992

Effects of consecutive administration of central and peripheral anticholinergic agents on respiratory sinus arrhythmia in normal subjects.

Respiratory sinus arrhythmia is thought to be vagally mediated, since it disappears after atropine, but the site of action of the drug (central vs. peripheral) accounting for this effect has not been elucidated. To investigate the effects of anticholinergic agents on respiratory arrhythmia, ten healthy subjects received an intravenous bolus of tropatepine (a presumed central antagonist) at a dose of 0.08 mg per kg of body weight, then, 7 min later, prifinium (a peripheral antagonist) at a dose of 0.1 mg per kg of body weight. Respiratory sinus arrhythmia during controlled breathing was evaluated as the area under the high-frequency peak of the heart rate variability spectrum coinciding with the respiratory frequency +/- 0.02 Hz. The power of this high-frequency peak decreased by 55% after tropatepine (P less than 0.05) with a concomitant increase of the mean RR interval from 930 to 1072 ms (P less than 0.01). When prifinium was added, a further but non-significant decrease of respiratory arrhythmia was observed, while the mean RR interval decreased from 1072 to 714 ms (P less than 0.01). The low-frequency components (0.05 to 0.15 Hz) of the power spectrum, significantly decreased (P less than 0.05) after infusion of both drugs. In conclusion, tropatepine depresses respiratory sinus arrhythmia with a paradoxical concomitant bradycardia. This suggests that tropatepine acts like a pure central muscarinic antagonist, in support of the hypothesis that a central cholinergic receptor is involved in the respiratory modulation of heart rate.

Adult↗
PubMed1992

[Efficacy of antihypertensive treatment in the French population. A multicenter survey].

In order to assess the efficacy of antihypertensive treatment in the population, a study was undertaken in 5 French cities during the commercial fairs of Grenoble, Marseilles, Nice, Toulouse and Lille. The blood pressure was measured according to the WHO recommendations in volunteers. The study included a total of 7107 subjects of both sexes, with 4064 subjects in the 35-64 year age group. The therapeutic efficacy was evaluated in the 791 hypertensive patients who knew their antihypertensive therapy. Taking < 160/95 mmHg as the criterion of efficacy, 52 to 73% of the hypertensive patients were well controlled. However, if the therapeutic objective of normalisation of the blood pressure (BP < 140/90 mmHg) is taken as the criterion of efficacy, only 23 to 29% of the hypertensive patients were controlled whilst their BP remained significantly higher than that of normotensive controls of the same age. The difference in efficacy of antihypertensive therapy between the cities may be explained by the heterogenicity of the populations whereas the treatment did not differ significantly. After adjustment analysis with respect to sex showed that women were better controlled than men whatever the criterion chosen. The group controlled at BP < 160/95 mmHg only differed from the group < 140/90 with respect to the average BP value which was higher before treatment and decreased less with treatment; though this did not achieve statistical significance. In matters of public health, if the ideal blood pressure is taken as < 140/90 mmHg, this study shows that the objective is only attained in one out of four patients in the population studied.

Adult↗
PubMed1991

Postextrasystolic sinoatrial exit block in human sick sinus syndrome: demonstration by direct recording of sinus node electrograms.

Ten patients with sick sinus syndrome having repetitive sinus node electrograms during long postpacing pauses were studied during programmed atrial stimulation. Sinus node activity was recorded using a percutaneous catheter electrode. A sinus node electrogram was recorded before the return atrial beat in seven patients; it was similar to the sinus node electrogram observed during postpacing pauses and is clearly identified because sinoatrial conduction time was markedly prolonged following the atrial extra beat. Complete sinoatrial exit block occurred in four patients. (1) Sinus node electrograms were thus validated both during postpacing pauses and during programmed atrial stimulation in most patients with sick sinus syndrome. (2) Sinoatrial conduction time was markedly prolonged after one extrasystole, accounting for supracompensatory atrial return cycles. (3) If it were cumulative following multiple extrasystoles, this effect could constitute the electrophysiologic link between an abnormal response during programmed atrial stimulation and the complete sinoatrial block recorded during the pauses that follow rapid atrial pacing.

Cardiac Catheterization↗
PubMed1991

Bipolar atrial triggered pacing to restore normal chronotropic responsiveness in an orthotopic cardiac transplant patient.

A not uncommon arrhythmia in cardiac orthotopic transplantation patients is sinus node dysfunction with chronotropic incompetence. This is a result of the surgical procedure that denervates the donor heart while the native sinus node may be normal but isolated in the remnant of the recipient atrial wall that serves as the anastomotic site. We were able to restore "normal sinus node function" in a heart transplant patient utilizing a bipolar single chamber pacemaker programmed to the triggered mode. A single unipolar active fixation lead was positioned in each atria. Both leads were connected to a bipolar AAT pulse generator utilizing a Y adaptator. The native atrium with its innervated intact sinus node effectively drove the donor atrium and thus the heart.

Arrhythmia, Sinus↗
PubMed1991

Wenckebach periods in sinoatrial block: experimental and clinical evidence.

The reality of sinoatrial Wenckebach periods (WP) has been suggested, but not proven, in the literature. We report experimental and clinical data showing WP in sinoatrial blocks. Experimental sinoatrial blocks were induced by superfusion of bepridil (10(-5) M) in 15 preparations of isolated rabbit right atria. Different types of block were observed, including Blumberger I block, i.e., sinoatrial WP. The recordings showed that the typical pattern of Blumberger type IA block and sinoatrial WP may be due to transient acceleration of the sinus rate, without change in the increment. We also observed sinoatrial WP in a 72-year-old patient on direct recordings of the sinus node (SN) electrical activity. In this case, transient acceleration of the sinus rate also seemed to be involved in the genesis of sinoatrial WP. Analysis of these clinical and experimental data showed similarities that may explain the mechanism of the WP. Usually type IA Blumberger block is said to involve a decrease in the sinoatrial increment to explain the atrial sequence (decrease in PP interval followed by a pause shorter than twice the value of the preceding cycle, then a cycle longer than the one preceding the pause). In fact, this pattern can be observed when the acceleration of the higher structure, the SN, induces block within the lower structure, i.e., the atrium.

Action Potentials↗
PubMed1991

[Prolongation of the CAST study.Is it justified to consider another trial?].

A possible prolongation of the CAST would be another trial of the same type, (CAST II), designed for high risk patients (1 year mortality over 20%). The aim of this study would be to confirm the hypothesis that the ratio efficacy/undesirable side effects of antiarrhythmic drugs is beneficial in this type of patient. The most important selection criteria would be an ejection fraction of less than 40%, the presence of repetitive arrhythmias, especially ventricular tachycardia on Holter monitoring and the recording of late ventricular potentials on surface averaging ECG. The patients would be included at about the 20th day after myocardial infarction in order to exclude as much as possible unstable coronary artery disease and ventricular arrhythmias on successive Holter recordings because this would make interpretation of the efficacy of antiarrhythmic drugs impossible. The ideal number of patients would be about 5,000 but this is unrealistic because the trial would only include high risk cases and there would be difficulties in recruiting this number even in a multicenter trial. During follow-up of 2 to 3 years, the surveillance of the therapeutic efficacy of the antiarrhythmics would have to be better than in the CAST. The most delicate methodological problem would be the randomization of patients as the formation of a placebo group is unethical in high risk coronary patients with severe or malignant ventricular arrhythmias. The use of the only proved cardioprotector drugs, the betablockers, in all these high risk patients would be one solution, even if it might introduce a bias in the results.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Arrhythmia Agents↗
PubMed1991

[Prognostic value and development of late potentials after aortocoronary bypass. A prospective study of 100 patients].

Ventricular late potentials are post-infarction markers of the risk of ventricular tachycardia and sudden death. In order to assess their prognostic value and evolution after coronary bypass surgery, 100 patients underwent signal-averaged electrocardiographic recordings 24 hours before and 9 days after surgery, and were then prospectively followed up for 40 +/- 8 months. Patients who displayed late ventricular potentials underwent an additional recording at 5 months with 24 hour Holter monitoring. The average age of the patients was 57.0 +/- 8.4 years; 55 had previous myocardial infarction; 32 had triple vessel disease; the mean left ventricular ejection fraction was 59.7 +/- 12.4%. Ventricular late potentials were recorded in 17 patients before surgery and their left ventricular ejection fraction was significantly lower (51.4 +/- 11.5% vs 61.4 +/- 11.9%: p less than 0.05). There was one operative death in a patient with late ventricular potentials. After surgery, late ventricular potentials were only recorded in 6 patients: at the 9th postoperative day in 3 cases and at the 5th postoperative day in 3 cases. Ventricular late potentials appeared postoperatively in 5 patients, 4 of whom had suffered perioperative myocardial infarction. The recordings became normal at the 5th month in 2 of these 5 patients. Holter monitoring at the 5th month compared with a control group, showed a significant correlation between left ventricular potentials and frequent repetitive or polymorphic ventricular extrasystoles. The 40 month survival rate was excellent: 2 patients were lost to follow-up; there were 3 cardiac deaths, one of which was sudden and 4 non-cardiac deaths. All patients with late ventricular potentials were still alive. These results show that late ventricular potentials persist after coronary bypass surgery in 2/3 of patients; their prognostic significance is not obvious. The low incidence of postoperative sudden death could be attributed to the favourable overall effects of revascularisation rather than on the arrhythmogenic substrate.

Adult↗
PubMed1991

A double-blind, randomized, comparative study of nitrendipine and enalapril in elderly hypertensive patients.

We conducted a randomized, double-blind, double-placebo study in two groups of elderly hypertensive patients aged over 60 years to compare nitrendipine to enalapril, given once daily over 4 months, as monotherapy with 20 mg tablets. Clinic blood pressure was measured monthly and 24 h ambulatory monitoring was obtained at day 0 and day 120. Fifty-two patients entered the study (22 in the nitrendipine group, 30 in the enalapril group); 4 patients in both groups were dropped from the study because they withdrew their consent to participate. Three patients under nitrendipine and five patients under enalapril were not included in the analysis of data because of insufficient follow-up. The two groups were comparable on final analysis. The clinical blood pressure was similarly reduced in both groups at 24 h postdose (172/97 to 157/85 mm Hg on nitrendipine vs. 177/98 to 154/86 mm Hg on enalapril). Seventy percent of the patients had their blood pressure normalized at the end of the study in the two groups. With ambulatory blood pressure recording, no 24 h blood pressure significant differences were found on day 120 when we calculated the mean of systolic blood pressure (SBP) or diastolic blood pressure (DBP) (137 +/- 12/82 +/- 9 mm Hg on nitrendipine vs. 136 +/- 16/82 +/- 11 mm Hg on enalapril), or for daytime or nighttime periods. The pulse pressure or the mean of the five highest SBP values was also similar in nitrendipine and enalapril patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

[Circumferential laser thermo-exclusion of post-infarction ventricular tachycardia. Apropos of 11 cases].

Circumferential laser thermoexclusion was assessed in the treatment of postinfarction ventricular tachycardia resistant to drug therapy in 11 patients between December 1986 and April 1989. There were 10 men and 1 woman with an average age of 63.7 +/- 5.6 years whose ventricular tachycardia occurred 10.7 +/- 7.5 years after infarction. All had left ventricular aneurysm or an akinetic plaque. Circumferential thermoexclusion was carried out by Mesnildrey's method, systematically associated with resection of the aneurysm or, when this was not feasible, with coronary revascularisation. Programmed ventricular stimulation was performed before and after surgery in 8 patients. Sustained ventricular tachycardia remained inducible in 4 patients after surgery but the prescription of antiarrhythmic drugs in 2 of these cases resulted in tachycardia becoming non-inducible. The increase in the left ventricular ejection fraction after surgery was not statistically significant (36.9 +/- 9.4% to 44.4 +/- 12.8%). After an average follow-up of 16.7 +/- 10.6 months, there were 2 cardiac deaths not related to arrhythmias (18%), 1 early at the 20th postoperative day and 1 late, 10 months after surgery. There were 2 recurrences of tachycardia (18%) controlled by antiarrhythmic therapy. Late ventricular potentials were recorded in 9 out of the 11 patients before surgery but in only 3 of these cases (33%) after surgery. Circumferential laser thermoexclusion guided visually in the border zone of the infarct scar would seem to be a simple, safe, rapid and therefore attractive, surgical antiarrhythmic technique, the efficacy of which should be evaluated by programmed ventricular stimulation. This should be undertaken on a large scale in order to define the indications and results of this method.

Aged↗
PubMed1990

[Late potentials].

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Arrhythmias, Cardiac↗
PubMed1990

Efficacy and tolerance of sustained-release diltiazem 300 mg and a diuretic in the elderly.

A randomized, double-blind, parallel study has been performed to compare the antihypertensive action and clinical and biological tolerance of monotherapy with two different substances: sustained-release diltiazem 300 mg and a diuretic combining 25 mg of hydrochlorothiazide and 50 mg of triamterene (HCT-T). Antihypertensive treatment was suspended at least 15 days before initiation of a placebo period that lasted 14 days and allowed confirmation of persisting hypertension. Eighty-five patients who were at least 65 years old were included in the study: 42 in the group treated with sustained-release diltiazem 300 mg and 43 in the group treated with a diuretic. All of them presented with mild to moderate arterial hypertension, characterized by supine diastolic blood pressures (supine DBP) of 95-115 mm Hg. Duration of treatment was 3 months. After 1 and 3 months, efficacy and tolerance of the antihypertensive treatment were evaluated. On day 30, a significant decrease (p less than 0.0001) in the main parameter, i.e., supine DBP, as well as other parameters such as standing diastolic blood pressure (standing DBP), supine systolic blood pressure (supine SBP), and standing systolic blood pressure (standing SBP) was observed. Blood pressure was reduced by 18, 16, 28, and 26 mm Hg, respectively, in the sustained-release diltiazem 300 mg group and by 13, 12, 21, and 18 mm Hg, respectively, in the diuretic group. Moreover, on day 90, blood pressure values were maintained in the diuretic-treated group, whereas an additional significant reduction in supine DBP (p less than 0.002) was noted in the sustained-release diltiazem 300 mg-treated group (-4.8 mm Hg).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1988

[Late ventricular potentials. Clinical applications and relation to severe ventricular arrhythmias].

The recording of late ventricular potentials with high amplification cardiography (HAC) permits to identify patients presenting a risk of sudden death and ventricular tachycardia, especially in the later stage of myocardial infarction. Few authors have studied the prevalence of these potentials in other heart diseases presenting a risk of sudden death. Most series in the literature are too small to specify variations in the prevalence of these potentials according to the severity of the coronary disease. For this purpose, 835 patients including 535 coronary patients were evaluated with HAC compared to data from coronary angiography and Holter test. An automatic quantification method of the late potentials was used on 131 healthy subjects. The prevalence of late potentials is 32 p. cent after infarction, and 75 p. cent when a chronic ventricular tachycardia is present. These potentials retain their significance of tracers of ventricular arrhythmias in primary dilated myocardiopathies, with a prevalence of 25 p. cent reaching 50 p. cent in case of ventricular tachycardia. Their recording in the presence of idiopathic ventricular extrasystoles must be an indication to look for an underlying cardiopathy. It is possible to record them in other diseases especially in advanced valvular cardiopathies, as well as in right ventricular dysplasias with arrhythmia where their presence has a great diagnostic value.

Arrhythmias, Cardiac↗
PubMed1987

[Sudden death of cardiac origin].

Every minute one patient in the world suddenly dies, of heart disease in the vast majority of the cases. Most of these sudden deaths of cardiac origin are due to ventricular tachycardia and/or fibrillation on a background of ischaemic heart disease. It is now recognized that as much as left ventricular dysfunction these ventricular arrhythmias are of sombre prognosis. To prevent sudden death of cardiac origin, therefore, patients with severe ventricular arrhythmia and consequently at high risk must be identified. Among examinations used for this purpose, the Holter monitoring method is of considerable value as it provides qualitative and, mostly, quantitative information on the arrhythmia. Programmed stimulation--a much more invasive method--has a prognostic value which varies from one author to another. On the other hand, late potentials recording is a simple and innocuous procedure, apparently most reliable as indicator of complex ventricular arrhythmias and sudden death. In spite of all these recent technical advances, the prevention of cardiac sudden death remains problematic since no epidemiological study has yet demonstrated that major reduction or even suppression of ventricular arrhythmias by antiarrhythmic drugs can significantly reduce the coronary mortality rate.

Arrhythmias, Cardiac↗
PubMed1987

Propafenone versus disopyramide: a double-blind randomized crossover trial in patients presenting chronic ventricular arrhythmias.

In vitro and in vivo electrophysiological studies have shown that propafenone could be classified as a class I antiarrhythmic agent. The aim of this study was to investigate the short-term antiarrhythmic efficacy and safety of propafenone in 10 patients compared to disopyramide in a double-blind randomized protocol. Included patients suffered from ventricular arrhythmias with at least 60 ventricular premature beats (VPB) per hour refractory to at least two other antiarrhythmic agents. At the end of the control period and of the two treatment periods during which patients received either propafenone (300 mg three times a day) or disopyramide (200 mg three times a day), clinical examination, Holter recordings, electrocardiogram, and clinical laboratory tests were performed. The PR interval and the QRS interval were significantly increased with propafenone, but not with disopyramide. The cQT interval was not significantly changed by either propafenone or disopyramide. Heart rate was decreased with propafenone (p less than 0.05) with no change in the diurnal/nocturnal circadian ratio variation. Heart rate was significantly decreased with disopyramide only during the day. Five of nine patients in the propafenone group and two of nine patients in the disopyramide group showed a reduction in ventricular premature beats greater than 80%. Total resolution of severe arrhythmias (repetitive events) was seen in 5 of 8 patients with propafenone; 2 of 8 with disopyramide. Adverse events, when they occurred, were mild (visual disturbances, epigastric discomfort, changes in taste perception, transient atrioventricular block with propafenone, and photophobia with disopyramide), and did not require reduction or discontinuation of study drug.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗