Biomedical subjects

Y Ben Ameur

Publications and source records attributed to Y Ben Ameur.

At least 19 recordsLinked to original sources

PubMed2006

[Conductive disorders following open-heart valvular surgery. Concerning 230 operated patients].

AIMS: Conductive disorders following open-heart valvular surgery represent serious complications that may require definitive pacemaker implantation. The natural history of these troubles is not well established thus, controversy persist concerning the timing of pacemaker implantation. In this study we identify the predictive factors of permanent conductive disorders in order to assess the optimal time of pacing. METHODS AND RESULTS: Two hundred thirty valvular replacements were done between 1993 and 2003. The mean age of our patients was 42 +/- 13.4 years. Rheumatic valvulopathies accounted for 76% of cases, with 54% of multiple valvulopathies. Twenty-two patients (9,5%) had an early postoperative conductive disorder, 9 of them (4%) were definitively implanted after a mean delay of 31.8 days. Preoperative bifascicular bloc and early installation of postoperative high-grade conduction disturbances and its persistence for more than 48 hours are significantly associated with permanent postoperative conductive disorders (respectively P = 0.04 and = 0.03). Aortic valve surgery and infective endocarditis were more frequent in the implanted group but the difference was not significant. CONCLUSION: After open-heart valvular surgery; predictive factors of definitive conductive troubles justify an earlier pacemaker implantation. This attitude may accelerate the hospital discharge and decrease the disease cost effectiveness.

Adolescent↗

PubMed2003

[Prognostic significance of second and third degree atrioventricular block in acute inferior wall myocardial infarction].

High degree atrioventricular block complicates inferior wall acute myocardial infarction in 10 to 15% of cases. Its significance is still controversial. In this study, we have analysed 152 observations of acute inferior wall myocardial infarction during hospitalisation period. The mean age of our patients is 60 years, 48.7% of them have received fibrinolytic treatment. Second or third degree atrioventricular block was detected in 33 cases (21.7%). Mortality is higher in inferior wall myocardial infarctions with atrioventricular block than in those without atrioventricular block (12% versus 2.5%, p < 0.05). Hemodynamic complications like cardiogenic shock due to the extension of the infarction to the right ventricle and left ventricle insufficiency are more frequent (18% versus 3.4%, p < 0.01 and 12% versus 3.5%, p < 0.01 respectively). It appears that the infracted mass of myocardium is larger in case of atrioventricular block, this is assessed by comparing the average value of the peak of creatine Kinase in the two groups with and without atrioventricular block (1534 IU versus 1096 IU, p < 0.02) and by considering the rate of low ejection fraction (EF < 40%) in each group (44.6% versus 16%, p < 0.01). In our study, we note that thrombolysis does not affect the incidence of atrioventricular block (19% and 24% in thrombolyed and not thrombolyzed patients respectively) but it seems that thrombolysis improves the outcome of these patients. The occurrence of atrioventricular block in acute inferior wall myocardial infarction is related to the presence of an important right coronary artery that is occluded, the recanalisation of this vessel leads often to rapid regression of the block that is no longer pejorative.

Acute Disease↗

PubMed2001

[Endocavitary implantation of a permanent pacemaker in the contralateral side of right pneumonectomy: a case report].

The definitive endocardial stimulation is easy to install, allows a stable position of the leads, and a satisfactory stimulation thresholds for a long period. The epicardial approach is reserved for some rare indications including infectious contexts. The endocardial approach has been considered for a 67 years man with a complete AV block and an atrial fibrillation. This patient had undergone a right pneumonectomy 15 years before. A VVIR pacemaker has been implanted successfully by an internal jugular vein approach, and connected to a passively fixed unipolar lead. Because of the right ventricle deformation which made it unrecognizable, even by angiography means, we had to face major difficulties to position the lead. The epicardial approach should be considered even if a direct unique lung controlateral approach is easier than homolateral, because it allows us a quick ventricular access under the view control.

Aged↗

PubMed2001

[Mitral stenosis secondary to Hurler's syndrome].

Valvular disease in mucopolysaccharidosis type I-Hurler (MPS/1H) is relatively common, but mitral stenosis is very rare in this genetic abnormality. The authors describe the case of a 16-year old girl with Hurler's syndrome diagnosed at 4 years of age. The morphological features were characteristic: bridged nose, thickened lips, macroglassia, short neck (gargoylism, short, thick fingers and limitation of brachial and fore-arm flexion. She presented with stage II dyspnoea and paroxysmal nocturnal dyspnoea. Radiological and echocardiographic studies revealed severe mitral stenosis with haemodynamic complications requiring mitral valve replacement. Anatomopathological analysis of the mitral valve confirmed mucopolysaccharide deposits as the cause of this particular case of mitral stenosis.

Adolescent↗

PubMed2001

[Indications for definitive cardiac stimulation].

Within less than a half-century, after the early rising of cardiac pacing, we witness a dramatical in crease of its indications. After the initial aim, which was to prevent transient ischaemic events, and sudden death due to bradycardia, some more physiological objectives have--progressively appeared, such as improvement of patient's quality of life, and optimization of the cardiac performance to fulfill the metabolic needs. The indications of cardiac pacing are nowadays extended to the fields of haemodynamics and rythmology. Numerous studies are advocating the interest of the cardiac pacing in pathologies such as obstructive and dilated cardiomyopathies specially for the improvement of the NYHA functional status, life comfort and effort sustain. On another hand, newly discovered antiarrhythmic virtues of atrial pacing are of a great interest for a certain type of atrial fibrillations such as vagal induced fibrillations, atrial diseases and atypical flutters. For conclusion: after becoming mandatory for bradycardias, cardiac pacing is conquering new indications on the fields of arrhythmias and cardiomyopathies. Within a close future, scientific evidences could definitely validate çardiac pacing using on these new fields.

Anti-Arrhythmia Agents↗

PubMed2000

[Place of definitive cardiac stimulation in cardiomyopathies and atrial arrhythmia].

Definitive cardiac stimulation ralatually used for brady cardia are going to be in the third millennium the specific therapy of arrhythmia and cardiomyopathy. In the last 10 years, may progress occur in the use of cardiac stimulation as hemodynamic therapy of obstructions hypertrophic and dilated cardiomyopathies resistant to conventional medical treatment. Moreover auricular stimulation present antiarrhythmic effects in some atrial arrhythmias as auricular fibrillations auricular diseases and atypical flutters. It confirmed by prospective multicentric randomized trials cardiac stimulation may represent in the future a good physiopathologic and efficient treatment free from the side effects of drugs that remain partially active. These perspectives needs to be modulated by the known and acceptable risks of a definitive cardiac stimulation.

Atrial Fibrillation↗

PubMed2000

[Infectious enterococcal endocarditis associated with Laubry and Pezzi syndrome].

Laubry and Pezzi syndrome is a rare but serious complication of ventricular septal defect that increase the infectious endocarditis risk. Authors report a case of an 18 years old young girl presenting an enterococcus infectious endocarditis associated to Laubry and Pezzi syndrome. Initial course is not favourable requiring a surgical treatment in the acute stage. Bacterial endocarditis combined with Laubry and Pezzi syndrome have a poor prognosis needing observation and strict preventive precautions when a favoring factor is present.

Adolescent↗

PubMed2000

[Dilated cardiomyopathy secondary to acromegaly].

In acromegaly, dilated cardiomyopathy is rare. Indeed, arterial hypertension, coronary artery disease and hypertrophic cardiomyopathy are more common. The authors report a case of a 42-years-old man with dyspnea (class III NYHA) and palpitations. The cardiac echography showed a dilated cardiomyopathy. The investigations revealed an acromegaly as an etiology. Diagnosis was based on patient morphotype, a high level of growth hormone (GH) and a pituitary adenoma detected by magnetic resonance imagery. This case is characterized by the absence of arterial hypertension and hypertrophic cardiomyopathy. The coronary angiography was normal. Consequently, in this particular case, dilated cardiomyopathy seems specific to acromegaly.

Acromegaly↗

PubMed1999

[Right mid-ventricular stenosis with intact interventricular septum].

Pure infundibular stenosis of the right ventricle is a rare congenital anomaly. Right midventricular stenosis with intact interventricular septum is even rarer. It consists of obstruction of the trabecular zone of the right ventricle by a hypertrophied moderator band with or without abnormal muscle bundles. This anomaly can now be diagnosed by transthoracic echocardiography, while haemodynamic and angiographic diagnosis is reserved for doubtful cases. Two cases of midventricular stenosis are reported. In both patients, the diagnosis was suspected bu ultrasonography which showed a right intraventricular gradient of about 80 mmHg without identifying the exact site (infundibular or midventricular). The diagnosis was corrected by the operative findings. A good postoperative course was observed for both patients.

Adolescent↗

PubMed1998

Single radiofrequency application to cure atrioventricular nodal reentry: arguments for the slow pathway origin of the high-low frequency slow potentials.

BACKGROUND: High-low frequency slow potentials are thought to be related to the slow AV pathway conduction. Their use was proposed to guide radiofrequency (RF) ablation of atrioventricular nodal reentrant tachycardia (AVNRT). The present study was designed to determine the prospective value of these high-low frequency slow potentials to guide AVNRT ablation using a single RF application. Single RF application could indeed reduce the size of the lesion created in the viciny of the specialized AV conduction system and shorten the radiation exposure and the overall duration of the procedure. RESULTS: Forty-one patients (14 men, 27 women, 45 +/- 16 years old) with AVNRT underwent slow pathway RF ablation guided by high-low frequency slow potentials. High-low frequency slow potentials were found in all patients along the tricuspid annulus and above the coronary sinus. Ablation was always performed in the posterior part of Koch's triangle. The mean A/V amplitude ratio of the successful site was 0.43 +/- 0.59. In 32 patients (78%) AVNRT was no longer inducible after a single RF application. Procedure and radiation times were 35 +/- 31 and 13 +/- 12 min respectively. Five patients required 2, 3 patients 3, and 1 patient 6 RF applications. The mean number of RF applications was 1.4 +/- 0.9 (median = 1). In the 32 patients who required only one RF application, 24 (75%) had an obvious dual AV nodal pathways with a jump before ablation, which completely disappeared in 18 of them (75%) after ablation. In the 6 remaining patients, who still had a jump after 1 RF application, there was no significant change in either conduction times or refractory periods concerning both the anterograde and retrograde AV conduction. No patient had PR interval purlongation. After a mean follow up of 11 +/- 5 months, recurrence was observed in a single patient who received 2 discontinued RF applications. CONCLUSION: Catheter-mediated ablation of AVNRT using high-low frequency slow potentials to localize the slow AV pathway is feasible and safe. Using this technique, a single RF application was successfull in 78% of patients, and slow pathway characteristics were completely eliminated in 75% of patients. The radiation time and the procedure duration were short. This suggest that, in patients with AVNRT, the choice of an appropriate RF target can reduce procedural duration.

Action Potentials↗

PubMed1998

[Sinus node dysfunction after complete correction of tetralogy of Fallot. Report of a case].

Atrioventricular conduction defects after complete correction of tetralogy of Fallot are well known and their prevalence is decreasing with improved operative techniques. On the other hand, sinus node dysfunction has not been described after this type of surgery. The authors report the case of a 24 year old patient operated at the age of 2 for a favourable form of tetralogy of Fallot. In the long-term, this patient had a minimal anatomical sequel (mild pulmonary insufficiency) and first degree AVB with complete right bundle branch block with sinus bradycardia on the surface ECG. A recent aggravation of the patient's functional status led to rhythmological investigation which showed chronotropic atrial incompetence with nodal atrioventricular delay. The patient was implanted with a permanent DDD cardiac pacemaker programmed in the DDDR mode with a good outcome. Atrial chronotropic incompetence is one of the modes of expression of sinus node dysfunction. This has not been previously described in this context. This form of sinus node dysfunction should be systematically excluded after surgical cure of tetralogy of Fallot by exercise stress testing and 24 hour Holter ECG. Symptomatic patients are greatly improved by permanent cardiac pacing with hysteresis.

Adult↗

PubMed1997

[Determinants of malignant vasovagal syncopes with asystole disclosed by the tilting test and therapeutic implications].

UNLABELLED: In order to evaluate the determinants of malignant vasovagal syncope with asystole revealed by the tilting test and to determine the possible therapeutic implications, 179 patients (91 women and 88 men, mean age 36.6 +/- 20.1 years) referred for the assessment of unexplained a were studied. The test was performed with a tilt of 60 degrees for 45 minutes. A bolus of isoprenaline (0.02 to 0.08 microgram/kg.min) was injected in the case of a negative passive test. Asystole was defined as a ventricular pause lasting > or = 5 seconds. RESULTS: Ten (13%) of the 77 patients with a positive tilting test experienced a cardio-inhibitory reaction with prolonged asystole lasting an average of 11.9 +/- 4.9 seconds. Compared to the other 67 patients with a positive test, those with asystole were younger (23/9 +/- 14.8 years vs 32.9 +/- 18.5 years, NS) and had a more frequent history of convulsions (6/10 vs 9/67, p = 0.05) during spontaneous episodes and trauma (9/10 vs 27/67, p = 0.005). Implantation of a pacemaker was chosen first-line treatment for the first 6 patients. Their follow-up tilting tests remained positive (pre S = 4, S = 1) despite DDD stimulation of 45 bpm. Five of these patients and the following 4 patients were retested under beta-blockers. In six patients treated with beta-blockers, the clinical symptoms resolved completely (n = 3) or improved (n = 3), in contrast with 3 other patients in whom the tilting test remained positive with recurrence of asystole. The mean follow-up for the 169 patients is 22.7 +/- 11 months and the ten patients with asystole remained totally asymptomatic. CONCLUSION: An asystolic response during the tilting test is characteristic of vasovagal syncope described as malignant. The syndrome essentially affects young patients, with a more frequent history of trauma and convulsions. Beta-blockers appear to be at least as effective as permanent pacemaker to prevent symptoms in this specific subgroup.

Adrenergic beta-Antagonists↗

PubMed1997

[Ventricular fibrillation after radiofrequency ablation of the atrioventricular node].

The authors report the case of a 77 year old patient who underwent radiofrequency ablation of the atrioventricular node for chronic. Invalidating atrial fibrillation, refractory to pharmacological therapy. A single chamber ventricular pacemaker was implanted one week before interruption of AV conduction. Eleven applications (7 on the right and 4 on the left side of the interventricular septum) were required for successful ablation. Four hours later, the patient developed episodes of non-sustained polymorphic ventricular tachycardia and torsades de pointe. These arrhythmias were initiated by long cycle-short cycle sequences and preceded by changes of ventricular repolarisation (prolongation of the spontaneous and paced QTc and JTc intervals). Eight days after ablation, the patient had an episode of ventricular fibrillation reduced by external DC shock. This arrhythmia was also preceded by changes in ventricular repolarisation. This case demonstrates the potential proarrhythmogenic effect of radiofrequency ablation of the AV node with changes in ventricular repolarisation which induces malignant ventricular arrhythmias. The authors suggest an appropriate preventive attitude. The progression in two distinct phases (immediate and late) imposes prolonged arrhythmia monitoring.

Aged↗

PubMed1997

[VDD mode single electrode cardiac stimulation: indications, results and limitations of the method].

UNLABELLED: Several authors have reported the single atrioventricular (AV) electrode, comprising an atrial dipole floating in the right atrium, to be a system capable of providing results which are just as satisfactory as those of conventional systems (DDD). Between August 1992 and March 1995, a VDD single electrode pacemaker was implanted in 65 patients (mean age: 73 years +/- 17.2). The indication for implantation was isolated high degree AVB with no apparent sinus dysfunction. Four pacemakers were used: Vitatron (n = 24), Intermedics (n = 23), Medico (n = 13), Biotronik (n = 5). Intraoperative atrial endocavitary recording was 1.8 mV +/- 0.74. 17 patients died from a cause unrelated to pacemaker dysfunction. 4 patients were lost to follow-up. The remaining 44 patients were reviewed in our centre with a mean follow-up of 14.5 months +/- 7 months. Seven pacemakers (16%) were reprogrammed in VVI or VVI (R) mode, because of permanent atrial fibrillation in 3 cases, complete loss of atrial reception in 2 cases and late onset sinus dysfunction in 1 case. In the 41 patients in sinus atrial rhythm, the atrioventricular synchronization rate was greater than 90% in 88% of patients, equal to 76.3% in 2.4% of patients and atrioventricular synchronization was impossible in 9.6% of cases. CONCLUSION: The overall results of our preliminary experience of VDD mode single electrode pacemaker are moderate. The poor results essentially concerned patients with paroxysmal atrial arrhythmias prior to pacing.

Adolescent↗

PubMed1997

[Coxiella burnetti infectious endocarditis. Apropos of a case].

Chronic forms of Q fever (endocarditis) are rare, but are responsible for severe and desperately recurrent infections, resulting in multiple valve replacements with a reserved prognosis. The authors report the case of a 35-year-old patient with a known history of rheumatic fever, who developed blood culture negative infectious endocarditis on a mitral bioprosthesis. The diagnosis of Q fever was based on serological arguments. Despite long-term antibiotic therapy, serology remained strongly positive and was associated with repeated mitral valve disinsertion. The patient died immediately after the fourth operation in a context of haemodynamic failure. This clinical case emphasizes the importance of performing Q fever serology in any case of culture negative endocarditis and the therapeutic difficulties encountered in chronic recurrent endocarditis.

Adult↗

PubMed1995

[Congenital mitral insufficiency. Diagnosis, prognosis and treatment].

Between September 1973 and November 1993, 30 children with CMI underwent open-heart surgery. The mean age at operation was 6.63 years with a range of 8 months to 14 years. Twenty patients underwent reconstructive mitral valvuloplasty; 3 immediate failures and 1 case of stenosis of Carpentier's ring, occurring 7 years after the operation, were observed in this group. Among the 10 patients treated by mitral valve replacement, there were 4 deaths, including 3 from specific complications of the prosthesis. Conservative mitral surgery provides better results with far fewer complications that mechanical prostheses and must therefore always be attempted as the first-line procedure.

Adolescent↗

PubMed1993

[Annulo--aortic ectasia. Prognosis and treatment].

Nine cases of aneurysm of the ascending aorta responsible for aortic insufficiency were identified between 1975 and 1989. Seven of these fell within the context of Marfan's syndrome, while the other 2 were idiopathic. Aortic leak was found to be massive from the outset in 5 cases and progressively worsened in 2 other cases. Mean follow-up was 138 months. Five patients were treated surgically, with nil mortality. Three corrective procedures were used: aortic valve replacement only or in combination with an additional procedure concerning the aorta (3 cases), or composite graft using the Bentall technique as modified by Cabrol (2 cases). There were 2 late complications among the incomplete procedures (detachment of the valve graft, recurrence of aneurysm). The 4 patients who did not undergo surgery all died: twice of aortic dissection and as a result of myocardial dysfunction in the other 2 cases. These results confirm the potentially grave course of this condition and emphasise the usefulness of routine surgery. Mastery of surgical techniques now justifies the extension of the indications of prophylactic surgery to any aneurysm having reached 6 cm. The Bentall technique modified by Cabrol remains the treatment of choice.

Adult↗

PubMed1993

[Syphilitic aortic insufficiency. Apropos of a case].

The authors report a case of aortic insufficiency with aneurysm of the ascending aorta of syphilitic origin. The diagnosis was made only histologically in the presence of a syphilitic granuloma. This opportunity is taken to review the various aspects of cardiovascular syphilis.

Adult↗