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M Slama

Publications and source records attributed to M Slama.

At least 37 records · Page 2Linked to original sources

Further study on the carotid baroreflex system in the cardiovascular deconditioning induced by head-down tilt.

HYPOTHESIS: The responses of the carotid baroreflex and of the peripheral sympathetic system to stimulations induced by either lower body negative pressure (LBNP -40 mmHg) or cold pressor test were investigated in eight volunteers before and after 48 h in the -6 degrees head-down tilt (HDT). METHODS: Geometry (diastolic diameter and pulsatile distention) and dynamics (cross-sectional compliance and tangential tension) of the bulb and the common carotid artery were investigated using ultrasonic devices, echotracking and aplanation tonometry. The activity of the sympathetic system was evaluated through measurements of plasma concentrations of catecholamines (CAs) and 3,4-dihydroxyphenyl glycol (DHPG). RESULTS: During LBNP -40 mmHg, the pulsed tangential tension was decreased and the pressure amplification, induced by the reflexion of the pressure wave, was increased with no difference between before and after HDT. Since cross-sectional compliance and distensibility coefficient remained unchanged and the carotid contour of the waveform unaltered, it is concluded that the carotid reflexogenic area reads the same message during LBNP whether the cardiovascular system was deconditioned or not. Nonetheless, during LBNP after 48 h HDT, the heart rate accelerated faster and CAs and DHPG concentrations increased out of proportion, suggesting that the peripheral sympathetic activity was more reactive after HDT than before. Finally, forearm vascular resistances were measured in response to cold pressor test; they increased in the same proportion after HDT when compared with before. CONCLUSION: Results indicate that the carotid baroreflex and the peripheral sympathetic system were not deficient after 48 h HDT.

Adolescent↗

[Coronary surgery without extracorporeal circulation. Indications, methods and results. Apropos of 224 cases].

Coronary revascularization without cardiopulmonary bypass is evolving as an important technique. From January 1988 to September 1997, 224 patients underwent consecutively coronary artery bypass grafting without cardiopulmonary bypass in our institution. Indications for this type of revascularization were essentially: patients with a single coronary lesion and patients which presented an increased risk for extra-corporeal circulation. Follow-up was complete. The majority of patients were men (176) and the median age was 62 years. Most patients were in CCS III and IV (79%). Unstable angina was found in 19%, 4% had a recent trans mural infarction (< or = 48 hr), and 36% had an older infarct (> 48 hr). 8% were operated in emergency, 29% presented a restenosis following angioplasty, with 4% having a complication from angioplasty, and 0.8% were operated in cardiogenic shock. Redo surgery was seen in 4% of patients. 12% of patients had an ejection fraction less than 30%, 47% an ejection fraction between 30 et 49%, and 40% patients an ejection fraction greater than 50%. Mean Parsonnet score was 10. 185 patients (82.5%) underwent single bypass, and 39 patients (17%) multiple bypasses. Ten patients (4.4%) underwent hybrid revascularization with primarily surgical grafting followed by angioplasty. Postoperative outcome included: myocardial infarction in 16 patients (7.1%), 8 patients (3.5%) were reoperated for tamponade or bleeding, 2 patients (0.8%) developed a mediastinitis, and 1 patient (0.4%) had a neurological event. Hospital mortality was 4% (9 patients). Univariate and multivariate analysis identified two risks factors: age greater than 70 (OR 4.2, CI 1-18.4), and an ejection fraction less than 30% (OR 5, CI 1.2-21.6). Survival was 99.1% at 1 year, 94% at 3 years and 83.2% at 7 years. Post operative angina occurred in 33 patients, linked to a coronary anastomosis dysfunction in 9 patients (4.1%). A significant reduction of cost was found, compared to patients operated with extra-corporeal circulation. We conclude that coronary revascularization without cardiopulmonary bypass can provide satisfactory results, for patients with single coronary lesion, or for patients with an increased risk and multiple coronary lesions.

Aged↗

[Can the results of large-scale clinical trials be applied to clinical practice?].

The management of a patient in cardiac failure should lead the physician to ask if the patient might benefit from treatment with an angiotensin converting inhibitor. Meta-analyses give a positive reply but often lack detail. Analysis of large scale therapeutic trials is the only way to determine whether the results are applicable in an individual case. This analysis starts with validation of the methodology (correct randomisation, respect of double blind protocol, identity of groups) and synthesis of results expressed, if possible, in absolute values. In a second stage, the criteria of inclusion, exclusion, and the comorbidity of enrolled patients, should be compared with those of the patient under consideration. In addition, the amplitude of the therapeutic benefit and the importance of undesired effects must be taken into account in the therapeutic decision. This approach allows a reasoned prescription based on documented facts.

Angiotensin-Converting Enzyme Inhibitors↗

Intrapericardial fibrinolysis: a useful treatment in the management of purulent pericarditis.

Since the introduction of antibiotics into clinical practice, purulent pericarditis has become a rare disease. The major complication of the standard management for this condition is constrictive pericarditis. We report two cases of purulent pericarditis in which intrapericardial fibrinolysis was performed in order to minimize this complication. The first case was a 38-year-old man admitted to our intensive care unit (ICU) for management of constrictive pericarditis complicating purulent pericarditis diagnosed 17 days previously. The patient was treated with four intrapericardial injections of streptokinase (250,000 IU each). Fluid drainage and cardiac output were improved. No change in clotting parameters was noted. Pericardiectomy and esophagectomy were then performed for a diagnosis of esophageal neoplasm. The postoperative course was uneventful. The second case was a 16-year-old boy admitted with loss of consciousness due to cardiac tamponade. Percutaneous pericardiocentesis drained 900 ml of cloudy fluid. Two intrapericardial injections were performed (day 1 and day 5) without any complication. Pericardial drainage was withdrawn on day 13 and the patient was discharged from ICU on the same day. Six months later, there was no evidence of constrictive pericarditis. Intrapericardial fibrinolysis appears to be safe and effective when prescribed rapidly in the course of purulent pericarditis.

Adolescent↗

Improvement of internal jugular vein cannulation using an ultrasound-guided technique.

OBJECTIVE: To determine whether ultrasound guidance can help operators to improve the results of jugular vein access in the ICU. DESIGN: Prospective, randomized study. SETTING: General Intensive Care Unit of a University Hospital. PATIENTS: Seven-nine patients were assigned to internal jugular vein cannulation using anatomical landmarks alone (control group, n = 42) or with ultrasound guidance (ultrasound group, n = 37). INTERVENTION: All cannulations were performed by junior house staff under the direct supervision of a senior physician. In the ultrasound group, an ultrasonography (7.5 MHz) was used and the transducer was covered by a sterile sheath. The placement and direction of the cannulating needle were determined on the ultrasound image. MEASUREMENTS AND RESULTS: Internal jugular vein cannulation was successful in 37/37 (100%) patients in the ultrasound group and in 32/42 patients (76%) in the control group (p < 0.01). Average access time was longer in the control group (235 +/- 408 s vs 95 +/- 174 s, p = 0.06) and carotid artery puncture occurred in five patients in each group (p = 0.83). Jugular cannulation was successful at the first attempt in 26% in the control group and 43% in the ultrasound group (p = 0.11). Thirty-two patients (86%) in the ultrasound group and 23 patients (55%) in the control group (p < 0.05) were cannulated within 3 min. The cannula could therefore not be inserted within 3 min in 19 patients (45%) in the control group. Failure was explained by thrombosis (n = 1), small caliber of the internal jugular vein (< 5 mm, n = 3), abnormal vascular relations (n = 3). Among the ten primary failures of cannulation, an internal jugular vein catheter was able to be inserted in four cases by an experienced physician on the side initially selected and with ultrasound guidance in two cases. The catheter was inserted into the contralateral internal jugular vein under ultrasound guidance in the remaining four cases. CONCLUSION: Ultrasound guidance improved the success rate of jugular vein cannulation in ICU patients. Our results suggest that ultrasound guidance should be used when the internal jugular vein has not been successfully cannulated within 3 min by the external landmark-guided technique.

Aged↗

Hemodynamic correlates of effective arterial elastance in mitral stenosis before and after balloon valvotomy.

This study had the purpose of documenting the hemodynamic correlates of effective arterial elastance (Ea; i.e., an accurate estimate of hydraulic load) in mitral stenosis (MS) patients. The main hypothesis tested was that Ea relates to the total vascular resistance (R)-to-pulse interval duration (T) ratio (R/T) in MS patients both before and after successful balloon mitral valvotomy (BMV). High-fidelity aortic pressure recordings were obtained in 10 patients (40 +/- 12 yr) before and 15 min after BMV. Ea value was calculated as the ratio of the steady-state end-systolic aortic pressure (ESAP) to stroke volume (thermodilution). Ea increased after BMV (from 1.55 +/- 0.63 to 1.83 +/- 0.71 mmHg/ml; P < 0.05). Throughout the procedure, there was a strong linear relationship between Ea and R/T: Ea = 1.09R/T - 0.01 mmHg/ml, r = 0.99, P = 0.0001. This ultimately depended on the powerful link between ESAP and mean aortic pressure [MAP; r = 0.99, 95% confidence interval for the difference (MAP - ESAP) from -18.5 to +4.5 mmHg]. Ea was also related to total arterial compliance (area method) and to wave reflections (augmentation index), although to a lesser extent. After BMV, enhanced and anticipated wave reflections were observed, and this was likely to be explained by decreased arterial compliance. The present study indicated that Ea depended mainly on the steady component of hydraulic load (i.e., R) and on heart period (i.e., T) in MS patients.

Adult↗

[Loss of substance of the lateral region of the face].

The lateral region of the face is often exposed to trauma and may also be the site of tumor localization. Exeresis may lead to major tissue loss. We report several surgical techniques, from the most simple to more complicated, available for facial repair. Neighboring regions in the frontal or temporal area are used but a submental flap may also be useful.

Adult↗

Effects of antihypertensive drugs on large artery compliance.

The changes in arterial compliance following drug treatment have been studied mainly in hypertension. Physiologically, reduced arterial compliance independently affects blood pressure through an increase in systolic pressure and a decrease in diastolic pressure at any given value of mean arterial pressure. This review summarizes the pharmacological studies performed in recent years on the ability of antihypertensive drugs to modify arterial compliance. For the same decrease in mean arterial pressure, antihypertensive drugs may have differential effects improving arterial compliance (calcium channel blockers, converting enzyme inhibitors, alpha-blockers and some beta-blockers) or causing no change (dihydralazine, diuretics, propranolol) with resulting consequences on cardiac structure and function.

Antihypertensive Agents↗

[Fracture of the medial wall of the orbit. Apropos of 4 cases].

Fractures or the medial wall of the orbit are uncommon and clinical signs are often discreet. This report was focused on isolated fractures of the medial wall of the orbit. Blow-out trauma is usually the cause. In these cases the clinical signs ranged from simple ecchymosis to blindness by haematoma of the orbital cone. Computed tomography is a major tool for diagnosis and making therapeutic indications for these fractures. Treatment depends on the oculomotor involvements as measured by forced duction tests.

Blindness↗

[Double responses].

Double response is a rare electrocardiographic phenomenon requiring two atrioventricular conduction pathways with very different electrophysiological properties. Double ventricular responses are the usual manifestation: an atrial depolarisation (spontaneous or provoked, anticipated or not) is followed by a first ventricular response dependent on an accessory pathway or a rapid nodal pathway and then a second response resulting from sufficiently delayed transmission through a nodal pathway for the ventricles to have recovered their excitability when the second wave of activation reaches them. A simple curiosity when isolated and occurring under unusual conditions, particularly during electrophysiological investigation of the Wolff-Parkinson-White syndrome, the double response may initiate symptomatic non-reentrant junctional tachycardia when associated with nodal duality and repeating from atria in sinus rhythm. The functional incapacity and resistance to antiarrhythmic therapy may require referral for ablation of the slow pathway.

Atrioventricular Node↗

Peak oxygen uptake during exercise in mitral stenosis with sinus rhythm or atrial fibrillation: lack of correlation with valve area. A study in 70 patients.

Although the haemodynamic response during submaximal supine exercise in mitral stenosis has been well described, the determinants of peak oxygen uptake during maximal upright exercise are poorly characterized and may differ in sinus rhythm and atrial fibrillation. Seventy patients with isolated mitral stenosis underwent Doppler-echocardiography and bicycle exercise with respiratory gas analysis. Forty-two patients were in sinus rhythm (Group I) and 28 in atrial fibrillation (Group II). Peak oxygen uptake was 21.3 +/- 5.6 ml.min-1.kg-1 in group I and 18.1 +/- 5.1 ml.min-1.kg-1 in group II (P < 0.05). There was no significant correlation between indices of exercise tolerance (exercise duration, ventilatory threshold, peak oxygen uptake, indexed peak oxygen uptake, peak oxygen pulse) and valve area or gradient in either group. Indexed peak oxygen uptake was not correlated to delta oxygen pulse but was linearly related (r = 0.43) to delta heart rate (delta heart rate = peak heart rate/rest heart rate) in Group I but not in Group II. Thus, in patients with mitral stenosis, no correlation was found between the mitral valve area or the gradient at rest and maximal upright exercise tolerance, suggesting that peripheral adaptation and, in sinus rhythm, chronotropic reserve, are important compensatory mechanisms.

Atrial Fibrillation↗

[Non surgical reduction of false aneurysms of the femoral artery with echo-Doppler control].

The authors report four cases of repair of femoral pseudoaneurysms under pulsed (1 case) and colour Doppler (3 cases) guidance, performed between January and October 1992 and compare the results with previously published reports of this new technique. They obtained 3 complete successes without complications and 1 failure with complications and a contraindication to the method. A review of the literature and the personal experience of the authors are described. This effective and usually complication-free technique should be proposed as an alternative to surgery. It should be undertaken as early as possible and remains a long and fastidious procedure poorly adapted to present nomenclature of medical procedures. It should be systematically proposed in cases of pseudo-aneurysms complicating the implantation of endoarterial prostheses.

Aged↗

[Pericardial constriction caused by epicardial patches of automatic implantable defibrillators. Apropos of 3 cases].

The authors report three cases of pericardial constriction secondary to implantation of an automatic defibrillator. In one case, the pericardial constriction occurred 1 year after implantation and was associated with ascending infection of the patch electrodes from the stimulator; the patient died when the patch electrodes were removed, the infection having eroded the left ventricular wall. In the other two cases, signs of constriction appeared 2 years after implantation. In one of these patients, surgery showed a fibrous pericardial reaction deforming the patch electrodes with a favourable outcome when the electrodes were removed. The other patient refused surgery. In the three cases, the diagnosis was confirmed by right heart catheterisation and ventriculography which showed signs of adiastole and severe deformation of the ventricular contours. Pericardial constriction due to patch electrodes is a potentially serious complication of implantable automatic defibrillators, the prevalence of which may be underestimated. The use of endocavitary or extra-pericardial electrodes should avoid this complication.

Defibrillators, Implantable↗

[Electrophysiological mechanisms of ventricular arrhythmia in myocardial infarction].

In experimental models of coronary occlusion, the physiopathology of ventricular arrhythmias varies with its timing, there being three main phases: early, late and chronic. The early phase covers the first 30 minutes and is dominated by tachycardias and fibrillations resulting from multiple micro-reentry circuits which are the consequence of major changes in conduction and excitability created by acute ischaemia. These arrhythmias may be triggered by extrasystoles which have a different mechanism related to the injury current generated in the border zone between ischaemic and healthy cells. The late phase lasts about 72 hours: it is characterised by polymorphic ventricular extrasystoles and bursts of relatively slow ventricular tachycardia. Much more rapid tachycardia can be induced by stimulation. The origin of these arrhythmias is usually in the surviving Purkinje fibres of the subendocardium. The mechanisms are variable: abnormal automaticity, reentry or activity triggered by delayed after depolarisations. During the chronic phase, reentrant tachycardia is possible but only when induced by stimulation. Delayed conduction is the consequence of non-uniform antisotropism related to the disorientation of the myocardial fibres caused by fibrosis. In the clinical situation, most research has been centered on sustained monomorphic ventricular tachycardias of the chronic phase. Their mechanism is almost exclusively reentry (the circuits usually being located in the subendocardium) as suggested by the triggering and interruption of clinical tachycardias by stimulation, the recording of fragmented activation or prepotentials at the site of emergence of the tachycardia and the phenomena of pacing.

Arrhythmias, Cardiac↗

Doppler echocardiographic evaluation of valve regurgitation in healthy volunteers.

OBJECTIVE: To study the prevalence and the characteristics of physiological valve regurgitation. DESIGN: Pulsed wave Doppler echocardiography, continuous wave Doppler echocardiography and Doppler colour flow mapping were performed prospectively in healthy volunteers. SETTING: Echocardiography laboratory in a city hospital. PATIENTS: 32 consecutive healthy volunteers (age 21-49 years, mean age 29.4). MAIN OUTCOME MEASURES: Identification of regurgitation with colour Doppler flow mapping and measurement of the jet area, jet length, and maximal velocity of the regurgitation. RESULTS: Regurgitation was recorded at the pulmonary (100%), tricuspid (100%), mitral (56%), and aortic valves (6%). The velocity of pulmonary and tricuspid regurgitation was similar to that predicted from the pressure gradient calculated from the Bernoulli equation. The jet area and jet length were generally small. CONCLUSION: Trivial regurgitation from the pulmonary, tricuspid, and mitral valves is common in healthy people. It is important to take such regurgitation into account when valve disease is diagnosed.

Adult↗

[Role of coronary angiography in infarction without Q wave. Results of a prospective angiographic study].

Non-Q wave myocardial infarction is associated with a high recurrence rate of ischaemic events (angina and infarction). The artery responsible for the infarction is usually patent but stenosed and seems to be the cause of these complications. This prospective multicenter series of 66 patients treated by Heparin, Aspirin, Diltiazem and undergoing coronary angiography during the hospital period studied the artery responsible for the infarction and the value of coronary angiography in this setting. Several conclusions were drawn from the results: the precise diagnosis of the artery responsible for the infarct may be difficult (14%); the left circumflex artery or one of its branches is often implicated (47%); non-Q wave infarction is a various and heterogeneous group, including: infarctions located on small branch arteries, "warning" ischaemic episodes in the left anterior descending artery territory. definitive infarction of the left circumflex artery territory; nevertheless, this group is an intermediate state between Q wave infarction and unstable angina (low occlusion rate 26% and angiographic lesional appearances similar to those of unstable angina); early coronary angiography (48-72 h) seems to be useful to improve prevention of ischaemic recurrences by adequate revascularisation.

Adult↗