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B Valeix

Publications and source records attributed to B Valeix.

47 records · Page 3Linked to original sources
PubMed1983

[Relations between the site of significant monotruncular coronary stenosis and left ventricular function. Therapeutic implications].

The indications of coronary bypass surgery in single vessel disease remain controversial. Therefore, we carried out a retrospective study of the coronary angiogrammes and left ventriculography of 93 patients with single vessel disease (greater than 70 p. 100 stenosis) involving the left anterior descending (LAD) or dominant right coronary arteries (RCA) to evaluate the quantity of myocardium at risk. Five angio-hemodynamic parameters were compared: the ejection fraction (EF), the ratio of end systolic left ventricular pressure to volume (LVESP/LVESV), the velocity of circumferential fibre shortening (VCF), end diastolic volume (EDV) and end systolic volume (ESV). Six subgroups were defined: 28 proximal LAD stenosis (16 without and 12 with myocardial infarction (MI], 37 mid LAD stenosis (20 without and 17 with MI), and 28 RCA stenosis (8 without and 20 with MI). In all, there were 44 single vessel stenoses without MI and 49 with previous necrosis. Left ventricular function was normal in the absence of MI but deteriorated progressively in cases with MI and LAD disease. In cases of proximal LAD stenosis without and with MI, the hemodynamics showed: EF (p. 100) = 67,12 +/- 2,07 leads to 43,83 +/- 4,7 (p less than 0,001); LVESP/LVESV = 3,24 +/- 0,34 leads to 1,92 +/- 0,50 (p less than 0,05); VCF (s-1) = 1,28 +/- 0,05 leads to 0,74 +/- 0,06 (p less than 0,001); in cases of mid LAD stenosis without and with MI: EF = 69,1 +/- 2,08 leads to 45,11 +/- 3,42 (p less than 0,001); LVESP/LVESV = 3,64 +/- 0,39 leads to 1,46 +/- 0,12 (p less than 0,001); VCF = 1,32 +/- 0,008 leads to 0,74 +/- 0,06 (p less than 0,001). In contrast the change in LV function was minimal in patients with necrosis and RCA stenosis: EF = 70,37 +/- 3,85 leads to 56,4 +/- 3,19 (p less than 0,05); LVESP/LVESV = 5,20 +/- 1,83 leads to 2,56 +/- 0,36 (p less than 0,05); VCF less than 1,42 +/- 0,17 leads to 1,03 +/- 0,08 (p less than 0,05).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1982

[Myocardial infarction due to acute right coronary thrombosis. Treatment with in situ fibrinolysis, absence of angiographic residual stenosis].

The case of a 44 year old patient with inaugural postero-diaphragmatic myocardial infarction is reported. Coronary angiography performed at the 3 rd hour showed total occlusion of the right coronary artery at the level of its second segment. A streptokinase perfusion through a Judkins' catheter positioned in the ostium of the right coronary artery using Rentrop's technique, resulted in recanalisation of the vessel at the 45 th minute. Control coronary angiography on the 10 th day showed an angiographically normal right coronary circulation. The clinical course was complicated by a recurrence on the 12 th day with a new occlusion at the same level. This observation confirms: - the reality of acute coronary thrombosis as a mechanism of myocardial infarction in the absence of significant underlying atherosclerotic stenosis. - the value of early fibrinolytic therapy in situ for limitation of the infarcted myocardial tissues.

Adult↗
PubMed1982

Electrophysiology of tiapamil in humans.

Electrophysiological properties of tiapamil, a new calcium antagonist, were studied in 15 patients. His bundle recordings were obtained during sinus rhythm and following atrial and ventricular pacing. Studies were performed before and 20 min after slow injection of tiapamil (1 mg/kg). During sinus rhythm, the main effect was a significant prolongation of the P-R interval owing to lengthening of the A-H interval. QRS, P-A and H-V intervals remained unchanged whereas the R-R interval was significantly shortened. Antegrade Wenckebach point was significantly lower after tiapamil. There was no statistically significant effect of tiapamil on the effective refractory periods of atrium, A-V node and ventricle. Corrected sinus node recovery time and sinoatrial conduction time were unchanged although the V-A conduction interval was prolonged. This study suggests that, in the dosage used, the main effect of intravenous tiapamil is prolongation of both antegrade and retrograde A-V nodal conduction.

Adolescent↗
PubMed1981

[Calculation of the ejection fraction from simultaneously recorded systolic intervals and angiography. Comparative study].

Garrard, Weissler and Dodge have reported a close correlation (r = -0,90) between angiographic ejection fractions (EF) and the ratio of left ventricular preejection and ejection periods (PEP/LVET) in patients with left ventricular disease without simultaneous recording equation Y" = 1,25 - 1,25 x where x is the PEP/LVET ratio and Y" the ejection fraction. Using this formula a theoretical EF may be calculated when the PEP/LVET ratio is known. A number of precautions must be taken in measuring systolic time intervals (synchronous recordings, rapid and constant recording speeds of at least 100 mm/s, good quality tracings). Respecting these conditions, close correlations between the theoretical and angiographic EF were obtained. However, discrepancies were observed in some cases and so the relationship was examined with and without simultaneous recordings in 28 patients (19 with coronary artery disease). The equations obtained were Y = 1,2 - 1,51 x and Y = 1,04 - 1,04 x respectively. The correlations in the whole group and in the coronary subgroup were not as good when the recording was not simultaneous (r = -0,78, compared to r = -0,85). The theoretic EF appeared to be "optimised" under these conditions. The "optimisation" increased with increasing values of the PEP/LVET ratio. A downward correction had to be made for abnormally high values (for example for a PEP/LVET of 0,38, the EF had to be corrected by -3,1% and for a value of 0,50 by -10,5%). This was also applicable in the patients with coronary artery disease. Curiously, the equation relating simultaneous EF and PEP/LVET was very close to that obtained by Garrard (Ya = 1, 12 - 1,27 x, ra = -0,80). The theoretical EF calculated from this equation was very close to the angiographic value. However, it was slightly higher or lower in coronary patients with or without myocardial infarction. Garrard's equation would appear to be useful for repeated studies of the ejection fraction in these patients.

Adult↗
PubMed1979

[Use of dopamine in sequelae of extracorporeal circulation. Apropos of 50 patients].

Dopamine was used after open heart surgery in a group of 50 patients. The therapeutic indications were: diffuse coronary insufficiency in 27 cases, myocardial infarction in 12 cases and early septicaemic shock in 6 cases. In the other 5 cases, dopamine was prescribed for short lasting circulatory insufficiency. The dosage varied between 3-15 gammas/kg/min. The variations of different parameters were studied over 12 hours. Improvement of cardiac efficiency was an early feature (less than 3 h) and was observed for all dosages (above 3 gammas/kg/min). It was accompanied by a marked diuresis. The chromotropic effects were non-existent at these dosages. At medium-term dopamine was effective in 40 patients (80 p. 100). Dopamine is effective in over 3 out of 4 cases after cardiopulmonary bypass. Its effect is immediate, and is observed in dosages less than 10 gammas/kg/min.

Adult↗