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Biomedical subjects

J Mansourati

Publications and source records attributed to J Mansourati.

At least 55 records · Page 3Linked to original sources
PubMed1996

New insights into the pathophysiology of carotid sinus syndrome.

BACKGROUND: The pathophysiology of carotid sinus syndrome remains poorly understood. Currently, two main hypotheses are provided: a lesion at the level of carotid sinus receptors or a central defect at the level of the nuclei of the autonomic nervous system. The objective of our study was to present arguments in favor of one of these two hypotheses. METHODS AND RESULTS: Test selection was guided by the following hypothesis: a degenerative central or local lesion could be associated with dysfunctions in the structures surrounding or comprising the baroreflex centers or their pathways. To test this hypothesis, brain stem auditory-evoked potentials; somatosensory-evoked potentials; blink reflexes; sympathetic skin responses; and styloglossus, sternocleidomastoid, and superior trapezius muscle electromyography were systematically performed from the right and left sides in 17 patients with carotid sinus syndrome and in 17 sex- and age-matched control subjects. Similar responses were found in the two groups for the "central" tests. Contrasting with this result, the electromyographic analysis of the sternocleidomastoid muscle differed significantly between the groups: 13 (76%) had pathological responses in the carotid sinus syndrome group compared with only 4 (23.5%) in the control group (P < .01). Furthermore, the abnormality was found on the right and left sides in 9 patients (53%) in the study group and in none of the control group (P < .005). CONCLUSIONS: This study strongly suggests that the neuromuscular structures surrounding the carotid mechanoreceptors are involved in the carotid sinus syndrome; however, the exact mechanism remains speculative.

Aged↗
PubMed1996

Accuracy and mean duration of different protocols of head-up tilt testing.

Based on the results of our study, > 95% of patients with a positive passive tilt test are also positive during 3 micrograms/min, and especially 5 micrograms/min, isoproterenol tilt test. A proposed time-saving protocol would be to initiate the test with an isoproterenol infusion and to perform a 45-minute passive tilt only in those patients with a positive 5 micrograms/min (an infusion rate reported to have an excessive low specificity) isoproterenol tilt test, and to consider only those with symptoms associated with objective changes during this latter test as "finally positive." An alternative option would be to perform a 45-minute passive tilt only in those patients with a negative 3 micrograms/min isoproterenol tilt test.

Adolescent↗
PubMed1996

[Mortality and morbidity in the acute phase of myocardial infarction. Comparison of 3 patient cohorts admitted to hospital over 10 years].

The management of acute myocardial infarction has been transformed over the last thirty years by a number of therapeutic innovations. The authors decide to compare the outcomes of three cohorts of unselected patients admitted to hospital at 10 year intervals, to evaluate the impact of these innovations on morbidity and mortality. Six hundred and sixty one patient admitted to the Coronary Care Unit for acute myocardial infarction were included: Group I comprised 223 patients admitted consecutively during the period 1972-1973; Group II comprised 243 patients admitted between 1982-1983 and Group III comprised 195 patients admitted between 1992-1993. The average age was comparable, about 65 years, in the 3 groups, although there were gender differences. Taking into consideration earlier hospital admission, the in-hospital mortality decreased from 25% in Group I to 21.8% in Group II and to 15.4% in Group III (p < 0.05 between the first 2 groups and the third group). This decrease in mortality is even greater in anterior wall infarction and is observed in all ages. Similarly to selected patients in large scale randomised clinical trials, the ordinary "run of the mill" patient has also benefited from therapeutic innovations over the last ten years.

Adult↗
PubMed1996

[Mid-term outcome of escape rhythm after radiofrequency ablation of the atrioventricular junction].

UNLABELLED: Mid-term outcome of the underlying escape rhythm developed after radiofrequency ablation of the atrio-ventricular junction was studied in 50 consecutive patients (28 women and 22 men with a mean age of 66.2 +/- 9.6 years). The escape rhythm was assessed immediately after ablation and after 13.7 +/- 8 months. At the end of ablation: an escape rhythm was present in 38 patients (76%), with a mean rate of 40.7 +/- 9.7 beats/min and a QRS morphology identical to the preablation QRS morphology in 22 patients (58%). At follow-up: an escape rhythm was present in 37 patients (74%), with a slower mean rate of 36.4 +/- 6.8 beats/min (p < 0.05) and an unchanged QRS morphology in 87.5% of the patients. Patients presenting with an escape rhythm at follow-up were more frequently found to have a postablation escape rhythm (p < 0.01). Escape rhythm presence at follow-up was not influenced by age, presence of a cardiac disease, continuation of an antiarrhythmic treatment after ablation, use of a bilateral approach for ablation or number of radiofrequency applications. CONCLUSION: after abrupt inhibition of the stimulation, an escape rhythm was present only in 74% of the patients 13.7 +/- 8 months after atrio-ventricular junction radiofrequency ablation. QRS morphology was identical to the preablation morphology in 57% of the patients.

Aged↗
PubMed1995

Reimplantation of the right internal thoracic artery as a free graft into the left in situ internal thoracic artery (Y procedure). One-year angiographic results.

Reimplantation of the right internal thoracic artery, as a free graft, into the left in situ internal thoracic artery (Y procedure) has enabled us to bypass more distant marginal vessels, which was not possible by the bilateral technique alone. This prospective study was aimed at evaluating the clinical state of the patients and the degree of patency of grafts within 16 months of follow-up. All 80 patients who underwent the Y procedure between January 1988 and January 1992 were included. This group represented 10% of the 840 patients having coronary bypass during the same period. A total of 202 coronary anastomoses were performed in this series. Early postoperative (30 days) complications included three deaths (3.75%), eight myocardial infarctions (10%), one case of phrenic nerve paralysis (1.25%), two cases of respiratory failure (2.5%), and six wound infections (7.5%). At 3 months' follow-up, 96% of patients were free of symptoms. During the follow-up period, four patients died of noncardiac causes (lung, pancreatic, and brain cancer and rupture of an abdominal aortic aneurysm). At 1 year, 71 patients were free of symptoms (97%). Sixty-one patients underwent coronary angiography between 12 and 24 months. Six patients with peripheral arterial disease were not suitable for coronary angiography, and six refused to be tested. These 12 patients had normal thallium test results in the bypassed area (stress or dipyridamole test). The patency rate of the left internal thoracic artery was 98.3% (n = 60), occlusion rate 1.6% (n = 1), and incidence of threadlike arteries 4.9% (n = 3). Thus the rate of perfect patency was 93.4%. The patency rate of the right internal thoracic artery as a free graft was 93.4% (n = 57), occlusion rate 6.5% (n = 4), and the incidence of threadlike arteries 8% (n = 5). Thus the rate of perfect patency was 85.2%. A total of 169 anastomoses were studied. The rate of patency of the anastomoses to the left anterior descending coronary artery was 96% (n = 58) and the occlusion rate, 4% (n = 2). The patency rate of sequential anastomoses (side to side) to diagonal arteries was 100% (n = 16). Patency rate of anastomoses to obtuse marginal arteries was 95% (n = 58) and the rate of occlusion, 4.9% (n = 3). The patency rate of anastomoses to the posterior descending artery or distal branches of the right coronary artery was 80% (n = 4/5).(ABSTRACT TRUNCATED AT 400 WORDS)

Anastomosis, Surgical↗
PubMed1995

[Patency of left border artery bypass after 1 year; comparison of three techniques].

The one year results of three techniques of bypass grafting of the artery of the left border of the heart were compared in a retrospective study in 120 patients all undergoing left anterior descending bypass grafting with an internal mammary artery. Group I comprised 38 consecutive patients: the left border artery was bypassed with a venous graft. Group II comprised 49 consecutive patients who had the left border artery bypassed by an internal mammary artery in situ. Group III comprised 33 consecutive patients who had the left border artery bypassed by an internal mammary graft issuing from a Y-shaped construction (right internal mammary artery as a free graft reimplanted into the left internal mammary artery). The operative mortality, morbidity and functional results were comparable in the three groups. The rate of angiographic success of the left border artery graft at one year was: 65.7% in group I, 89.5% in group II and 87.8% in group III. The one year patency of internal mammary artery grafting of the artery of the left border was higher than that of venous grafts (p < 0.05).

Adult↗
PubMed1995

Frequency of obstructive sleep apnoea syndrome detected by means of a questionnaire in patients with coronary heart disease.

As previous studies have suggested an association between obstructive sleep apnea syndrome (OSA) and ischaemic heart disease, the aim of the present study was to evaluate the frequency of clinically relevant OSA in this selected population. From September 1992 to April 1993, 136 patients referred to the Cardiology Unit for suspected angina pectoris were asked to participate in the study. The main inclusion criterion was a stable coronary heart disease, diagnosed by angiography. A sleep questionnaire was administered by a trained physician. Patients who experienced one of the following symptoms: association of body mass index (-weight/height2) above 27.5 and heavy snoring, breathing stops, or daytime hypersomnolence, were selected for a nocturnal oxygen saturation recording. The occurrence of at least one desaturation, defined as a 4% fall from baseline, led to a full night-time polysomnography. One hundred and eight patients (78 males), satisfied the entry criteria. A pulse oximetry was performed in 15, and three patients experienced a significant desaturation. Finally, one patient satisfied the criteria of OSA. The estimated proportion of OSA amounted to 0.92%, in accordance with the prevalence of OSA described in the general population. Clinically relevant OSA does not appear to be more frequent in patients suffering from stable coronary heart disease. Systematic sleep investigations in such patients do not appear to be useful in daily clinical practice.

Aged↗
PubMed1995

[Contribution of doppler echocardiography to the diagnosis of the first attack of acute rheumatic fever].

Since 1944, the Jones criteria for the diagnosis of acute rheumatic fever have been regularly revised to integrate technical and diagnostic innovations. Echographic and Doppler criteria, however, remain unrecognised due to valvular insufficiency in healthy subjects. The aim of this study was to determine the cardiac lesions occurring in acute rheumatic fever and the diagnostic value of Doppler echocardiography. One hundred patients with an average age of 10 years were admitted to hospital because of a first attack of acute rheumatic fever between January 1991 and September 1992. Eighty-six had articular signs, 5 had chorea, but none had cutaneous lesions. Forty-seven murmurs of mitral insufficiency (MI) and eight of aortic insufficiency (AI) were detected; 10 children had signs of cardiac failure. Conduction defects were recorded in 12 cases. Echocardiography showed 7 pericardial effusions; often, the left heart chambers were dilated without alteration of the fractional shortening. The commonest lesions of the mitral valve were thickening of the two leaflets, the reduced mobility of the posterior leaflet, the rigidity of the anterior leaflet and 2 cases of ruptured chordae tendinae. The Doppler mode showed 73 cases of MI, 26 of which were at least moderately severe. These cases of MI were commonly excentric jets behind the posterior leaflet. There were 47 cases of AI, 10 of which were at least moderately severe. If all cases of moderately severe or mild AI and MI are considered as pathological when associated with suggestive morphological valve changes, the number of cases of carditis increased from 50 without the Doppler mode to over 80 with this mode. Doppler echocardiography validated the Jones criteria in 16 children. The authors propose Doppler echocardiography criteria for the validation of carditis.

Acute Disease↗
PubMed1994

[Permanent cardiac stimulation after aortic valve replacement: incidence, predictive factors and long-term prognosis].

Between January 1981 and June 1992, 382 patients, operated by the same surgical team, underwent aortic valve replacement for pure severe aortic stenosis. This population was divided into 2 groups according to whether or not surgery was complicated by the development of a conduction defect (atrioventricular and/or intraventricular block), necessitating permanent cardiac pacing. The aim of this study was to analyse not only the incidence and predictive factors but also the long-term prognosis of the paced patients (Group II: 22 patients) in comparison with the control group (Group I: 360 patients). The results showed: the incidence of permanent cardiac pacing after this type of surgery remains low (5.7%); the predictive factors of atrioventricular block requiring permanent pacing were: pre-existing conduction defect (p < 0.02), decreased ejection fraction (p < 0.05), calcification extending to the subaortic interventricular septum (p < 0.0001); the long-term prognosis of the patients was good with 5 and 10 year actuarial survival rates of 95.4% and 68.9% respectively, identical to those of the control group.

Actuarial Analysis↗
PubMed1994

[Can atrial fibrillation be managed without anti-arrhythmia drugs?].

Antiarrhythmic drugs are widely used in atrial fibrillation. The demonstration of severe pro-arrhythmic effects in recent years has led to the reappraisal of their indications in this pathology. Antiarrhythmic agents have three roles: reduction of the fibrillation, maintenance of sinus rhythm and, in case of failure, control of the ventricular response. In the first indication, although intravenous injection of Class Ic antiarrhythmics is effective in 70% of cases, there is an alternative: electrical cardioversion, which is effective in 90% of cases with the transthoracic method when a certain number of technical conditions are respected. The success rate is even better with endocavitary defibrillation. Sinus rhythm is sustained in only 25% of patients at one year with placebo and in 50% of patients with antiarrhythmic therapy. The alternatives in this indication are few at present and consist in right atrial pacing in cases of vagal fibrillation and biatrial pacing for resynchronizing the activation of the two atriae when there is a major interatrial conduction defect. The control of the ventricular response, in cases of permanent atrial fibrillation, is usually reserved to digitalis, betablockers, amiodarone and some calcium antagonists. They are often inadequate and an alternative is radiofrequency catheter ablation of the atrioventricular node, which requires permanent ventricular pacing. In conclusion, there are a few alternatives to antiarrhythmic drug therapy in atrial fibrillation, but they are relatively ineffective in maintaining sinus rhythm.

Anti-Arrhythmia Agents↗
PubMed1993

Transient outward current in young and adult diseased human atria.

In human atrial fibers, the action potential undergoes a major developmental change in shape in the months immediately after birth. Transient potassium outward currents, which may affect the shape of the action potential, have been studied using a whole cell voltage-clamp technique with single cells from the atria of young patients aged 3-60 mo. Transient outward current (I(to)) amplitude was measured as the difference between the peak current and the steady-state outward current (I(late)) at the end of the voltage step. The density of I(to) was significantly reduced in adult diseased cells (n = 18) compared with normal cells (n = 21) in a large range of potential and absent in young diseased cells (n = 13). Furthermore, the I(late) recorded in young cells was significantly greater (23.7 +/- 5.74 pA/pF at 60 mV) than in adult normal cells (12.71 +/- 2.25 pA/pF at 60 mV), whereas I(late) was not significantly different between both groups of adult cells. Nevertheless, a 4-aminopyridine-sensitive I(to) has been recorded in young cells. A decrease in the frequency of clamp steps (from 0.1 to 0.01 Hz) did not reactivate a I(to) in young cells. This absence of 4-aminopyridine-sensitive Ito in young cells probably results from either a normal developmental change of this current or from pathological alterations like those described in adult diseased atria.

4-Aminopyridine↗
PubMed1992

Atrial natriuretic factor release during exercise in patients successively paced in DDD and rate matched ventricular pacing.

Dual chamber pacemakers were implanted in nine patients with permanent second or third degree AV block (eight had complete retrograde block). Two identical exercise tests were performed after at least 1 month after implantation. During the first test (T1) the pacemaker was programmed to the DDD mode and heart rates were recorded every 15 to 30 seconds during exercise and 30 minutes after exercise. Following 30 minutes of rest, the implanted pacemaker was programmed to the VVT mode and driven by an external pacemaker via a skin electrode. The second exercise test (T2) was then performed and the rate of the external pacemaker was progressively changed to reproduce exactly the rate observed during T1 at the same exercise stress. Atrial natriuretic factor (ANF) levels were determined at rest, at regular intervals during exercise, and 30 minutes after exercise. ANF levels and release were statistically higher during rate matched ventricular, than DDD pacing. It is concluded that preservation of AV synchrony reduces ANF release induced by heart rate acceleration during exercise.

Aged↗
PubMed1992

[Rupture and extravascular migration of a vena cava filter. Apropos of a case].

The authors report the case of a 68 year old woman who underwent implantation of a Greenfield vena caval filter for recurrent pulmonary embolism. Migration of the filter out of the vena cava into the perivenal fat was discovered two years later during another embolic episode. One of the spokes of the filter had migrated into the iliac fossa. This case illustrates two possible complications of caval filters: rupture and migration. The increasing number of cases reported in the literature indicates the necessity of keeping a register of the complications encountered with different models to avoid the most dangerous ones.

Aged↗
PubMed1992

[Patency of the artery responsible for myocardial infarction: role on ventricular function and long-term outcome].

Out of 3,171 consecutive patients referred for coronary angiography, 240 were selected on the following criteria: recent primary myocardial infarction, single vessel coronary disease, no angioplasty or coronary surgery after the angiography which was performed 20 to 90 days after the onset of myocardial infarction. The patients were divided into 2 groups according to whether the artery responsible for infarction was patent (Group I: 115 patients) or not (Group II: 125 patients). The left ventricular ejection fraction was significantly higher in Group I (58 +/- 10.8%) than in Group II (53.7 +/- 11.3%) and end systolic and end diastolic left ventricular volumes were greater in Group II (51.8 +/- 22 ml/m2 and 88 +/- 22 ml/m2 respectively). Long-term follow-up (56 +/- 25 months in Group I and 61 +/- 26 months in Group II) was possible in 112 patients in Group I and 123 patients in Group II. Of the 7 patients who died in group II, 4 deaths were of cardiac origin; in addition, 2 cases of sustained ventricular tachycardia were observed in this group. None of the 6 deaths observed in Group I was of cardiac origin and there were no cases of ventricular tachycardia (p = 0.05). The functional status was identical in the two groups at the end of the study. These results suggest that the patency of the coronary artery responsible for myocardial infarction at a distance from the acute event is associated with better left ventricular function and a better long term prognosis.

Adult↗
PubMed1991

[Evaluation of beta-adrenergic blockader therapy in vasovagal syncope reproduced by head-up tilt test].

Increased sympathetic tone is one physiopathological mechanism of vasovagal syncope. In this case, betablocker therapy is logical. The reports in the literature suggest that the head-up tilt test can reliably reproduce vasovagal syncope. Ten patients (4 men and 6 women, mean age 59 +/- 18 years) who suffered from recurrent vasovagal syncopes (2 to 10 attacks in 6 patients and more than 10 in the other 4) with a positive initial head-up tilt test (syncope or severe dizziness with marked hypotension after a maximum of 40 minutes at 60 degrees) were treated with atenolol (200 mg daily in 7 cases and 100 mg daily in the other 3). A second head-up tilt test was performed 15 +/- 6 days later under betablocker therapy; this test was negative in 7 and remained positive in 3 cases. Irrespective of the result, the 10 patients followed the same therapy at the same dosage. After 9 +/- 5 months, 3 patients had another syncopal attack; 2 stopped taking their medication and the third patient continued the betablocker because there was a marked reduction in the frequency of his attacks. There were no further syncopal episodes during follow-up of the other 7 patients. The medium-term efficacy could not be predicted from the results of the second head-up tilt test. The following conclusions may be drawn from this study: The head-up tilt test becomes negative in 70% of cases after introducing betablocker therapy, assuming a 100% reproductivity. This treatment is effective in over half the patients at medium term and should be considered in patients with recurrent vasovagal syncope.

Adrenergic beta-Antagonists↗
PubMed1991

[One year results of sequential mammary artery anastomoses. 120 clinical cases. Angiographies: 71 patients].

From 1985 to november 1989, 270 patients underwent sequential anastomosis with left internal mammary artery (LIMA) on left descending artery (LDA) and diagnonal artery (DA). The first 120 cases have 100% one year follow-up. The perioperative status was: angina stage III or IV: 59%; myocardial infarction (MI): 45%, stenosis of 3 vessels: 52.5%; stenosis of main coronary artery: 10.8%. 2.25 anastomoses were performed per patient. Side-to-side anastomosis (kissing) were not diamond anastomoses but axial and longitudinal. The use of fibrin gllude provides regular curves of the graft between anastomosis. Mortality was 0.8%, morbidity was: MI: 4.2% (2 small infarcts in anterior vessels, 3 others in non-grafted vessels); mediastinitis: 1%; severe bleeding (reoperation): 1%. At one year 93% of patients are free from angina and 71 patients underwent angiographic assessment (145 LIMA anastomosis). Results are as follow: side-to-side anastomosis patency: 98.5%; distal anastomosis obliteration: 3%; LDA anastomosis patency: 95.7% overall sequential anastomosis patency: 97.6%. These results have led our cardiologist in Brest to naturally prefer a surgical approach than percutaneous angioplasty when LDA and DA are involved.

Adult↗