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Publications (7)5.85 Total impact

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    ABSTRACT: The electrophysiologic mechanisms of sinus dysfunction have recently been determined by direct recording of the sinus node electrogram. The association of various degrees of abnormalities in the formation of the impulse within the sinus node and of sinoatrial conduction block, represents the pathophysiological substrate of the mechanism of sinus node dysfunction. The purpose of this work is to present clinical and experimental data supporting the concept of sinus node isolation. In our clinical case, the sinus node was probably intact despite aspects of sinus node dysfunction on the surface ECG. Sinus node electrograms were recorded with a sinoatrial conduction time of 100 ms (normal values in our laboratory: 83 ms ± 38 ms). Atrial mapping demonstrated that (he area depolarized by the sinus node involved a 2 cm2 zone surrounding it. This perisinusal activity could not be recorded on the surface ECG. Both exit and entry blocks in the sinus node were demonstrated. Our experimental data showed a total desynchronization between the electrical activity of the sinus node and that of the atrium under hypoxic conditions. Both types of cases demonstrated that an atrial dysrhythmia was coexisting with regular sinus activity. From these data we concluded that a sinus node free from any pathological involvement could be associated with severe symptoms of sinus node dysfunction on the surface ECG.
    Pacing and Clinical Electrophysiology 06/2006; 11(1):23 - 24. · 1.75 Impact Factor
  • La Presse Médicale 01/1994; 22(38):1928. · 0.87 Impact Factor
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    ABSTRACT: From March 1990 to July 1991, 35 patients underwent coronary artery bypass grafts using the right gastro-epiploic artery (GEA). Twenty-nine patients had exclusively arterial grafts using a combination of GEA and internal mammary artery (IMA) in situ. The selection criteria for this group of 29 patients included a life expectancy exceeding ten years to avoid the need for reoperation due to deterioration of the grafts. This group consisted of 27 men and two women under the age of 70 years (mean age: 58 years, range: 36 to 70), 11 patients (38%) were under the age of 50 years and 15 (52%) were under the age of 60 years. Cardiac status was relatively well preserved. The mean ejection fraction was 58% (range: 25-70%). Fourteen patients (48%) had had a preoperative myocardial infarction. Fifty-five p. cent were smokers, 41% suffered from HT and 31% had a dyslipidaemia. Six patients (20%) had respiratory failure, 6 others (20%) were severely overweight and 2 patients were diabetic. According to the NYHA classification, 14 patients (48%) were stage IV, 9 patients (31%) were stage III and 6 patients (20%) were stage II. The mean number of bypass grafts per patient was 2.8 and 8 sequential bypass grafts (27%) were performed. The GEA was used in 29 cases, the left IMA was used in 28 cases, the right IMA was used in 13 cases and the epigastric artery was used as a free graft in 3 cases. Associated lesions included a resected left ventricular aneurysm. No associated valve procedures were performed.(ABSTRACT TRUNCATED AT 250 WORDS)
    Annales de Chirurgie 02/1992; 46(8):694-9. · 0.35 Impact Factor
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    ABSTRACT: Forty-five lower limb arterial lesions were treated by Nd Yag laser angioplasty using 1.4 and 2 mm hybrid catheters in 31 patients. This population comprised 28 men and 3 women (average age 63.8 +/- 3 years) 20 were in Stage II, 5 in Stage III and 6 in Stage IV of Fontaine's classification. The arteriographic lesions were 22 occlusions with an average length of 12.3 cm and 23 stenoses averaging 87% luminal reduction a few millimeters long to a maximum of a string of stenoses. Seventeen of these lesions were very calcified. The stenoses were situated on the iliac artery (7 cases), superficial femoral artery (28 cases), popliteal artery (9 cases) and the tibio-peroneal artery (1 case). There were no fatalities or recourse to emergency surgery. All patients underwent complementary balloon dilatation. The immediate patency rate was 91% in stenotic and 72% in occlusive lesions. At one week, the patency rate for stenotic lesions was unchanged but it had fallen to 59% for occlusive lesions (arteriographic evaluation). Angioscopy was used 22 times: it was indissociable to laser angioplasty as it enabled diagnosis and controlled the result. The use of thermal laser with hybrid catheters (metallic window tip) in endovascular procedures is a safe and effective method of treating stenosis and occlusion of lower limb arteries.
    Archives des maladies du coeur et des vaisseaux 12/1991; 84(11):1537-41. · 0.40 Impact Factor
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    ABSTRACT: This report describes a consecutive and prospective series of 136 patients, who underwent coronary bypass using the internal mammary arteries. Coronary angiography was routinely performed on all patients 8 days after surgery. A total of 137 operations (1 reoperation) were performed on 180 coronary arteries using 132 left internal mammary arteries and 25 right internal mammary arteries. Direct bypass was performed 133 times (73.8%), sequential bypass 23 times (25.5%) and free graft once. Bypass involved 1 coronary artery 89 times (65.4%), 2 coronary arteries 46 times (33.8%) and 3 coronary arteries in 1 case. The overall early success rate of internal mammary bypass in this series was 94.8% including 2 bypasses which were patent but non-functional. Of the 23 sequential bypasses, only 1 anastomosis out of 46 was not patent for a success rate of 97.3%. These good results are attributed to the large diameter of the mammary artery. Early postsurgical imaging is valuable for several reasons. It allows detection of surgical errors and improvement of the procedure. It enables distinction between residual primary surgical stenosis and secondary stenosis or genuine restenosis. It allows analysis of perioperative complications allows. No correlations between myocardial infarction and bypass obstruction were found. Finally, it permits endoluminal therapies such as thrombolysis (1 case in this series) and dilatation (2 cases). In conclusion, although we do not perform angiography routinely, our policy is to perform imaging in all cases of postoperative complications and after certain procedures such as sequential bypass.
    Annales de Chirurgie 02/1991; 45(2):82-9. · 0.35 Impact Factor
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    ABSTRACT: The electrophysiologic mechanisms of sinus dysfunction have recently been determined by direct recordings of the sinus node electrogram. The association of various degrees of abnormalities in the formation of the impulse within the sinus node and of sinoatrial conduction block, represents the pathophysiological substrate of the mechanism of sinus node dysfunction. The purpose of this work is to present clinical and experimental data supporting the concept of sinus node isolation. In our clinical case, the sinus node was probably intact despite aspects of sinus node dysfunction on the surface ECG. Sinus node electrograms were recorded with a sinoatrial conduction time of 100 ms (normal values in our laboratory: 83 ms +/- 38 ms). Atrial mapping demonstrated that the area depolarized by the sinus node involved a 2 cm2 zone surrounding it. This perisinusal activity could not be recorded on the surface ECG. Both exit and entry blocks in the sinus node were demonstrated. Our experimental data showed a total desynchronization between the electrical activity of the sinus node and that of the atrium under hypoxic conditions. Both types of cases demonstrated that an atrial dysrhythmia was coexisting with regular sinus activity. From these data we concluded that a sinus node free from any pathological involvement could be associated with severe symptoms of sinus node dysfunction on the surface ECG.
    Pacing and Clinical Electrophysiology 02/1988; 11(1):23-32. · 1.75 Impact Factor
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    ABSTRACT: The authors searched for intra-sinusal echos during electrophysiological investigation of 53 patients (41 men, 12 women, average age: 61 +/- 12 years). Cycles of sinus echos were recorded in 8 patients (15 per cent). The period during which sinus echos could be recorded was 125 ms (average 40.6 +/- 34 ms). Indirect assessment of sinus node function in patients with sinus echos was normal (corrected sinus node recovery time, estimated atrio-sino atrial conduction times using Narula's technique). A valid and reproducible direct recording of the sinus node potential was only possible in one patient. In this case the echo cycles were provoked by stimulation periods of between 440 and 320 ms (echo zone of 120 ms). All the echos obtained were preceded by a sinus node potential with a different duration and morphology to that observed during basal sinus cycles (respective sino-atrial conduction times 105 and 115 ms). In this patient we were also able to induce sinus echos after a single extrastimulus during the spontaneous rhythm. the echo zone was 130 ms and with a shorter coupling interval (310 ms) two successive sinus echos were recorded. The demonstration of intrasinusal echos by direct recording of the sinus node potential supports the experimental data of Allessie and Bonke on isolated right atrial tissues of the rabbit. Improvements in the technique of endocavitary direct recording of the sinus node potential in man should complete this data by showing the possibility of sinoatrial tachycardias due to reentry.
    Archives des maladies du coeur et des vaisseaux 09/1986; 79(9):1337-42. · 0.40 Impact Factor