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P Coste

Publications and source records attributed to P Coste.

At least 55 records · Page 3Linked to original sources
PubMed1994

[Continuous monitoring of cardiac output by analysis of the pulse contour].

One method of continuous cardiac output monitoring by analysis of the radial pulse contour (Qcp) relates left ventricular stroke volume and systolic blood pressure by calculating the impedence characteristic of the aorta (Zao). It was assessed during haemodynamic monitoring by comparing it with the thermodilation method in the pulmonary artery (Qtd) in 20 patients with cardiac failure due to dilated cardiomyopathy (6 cases) and ischaemic cardiomyopathy (14 cases) treated by inotropic agents or vasodilators. Over an average monitoring period of 35 hours 159 measurements of cardiac output were performed by the two methods. There was an excellent correlation between the two methods (r = 0.90; p < 0.001; Qcp = 0.97 Qtd). The systematic error (bias) between the two methods was about 2.5%. The accuracy of Qcp compared with Qtd was 12.5%. During infusion with a vasoactive agent (Piroximone), the method based on pulse contour analysis did not reflect sudden variations in cardiac output. The systematic error between the two methods rose to 19% of the value measured, reflecting the lack of adaptation of parameters of correction in this situation and which necessitated recalibration of Zao at least once after injection of the drug.

Cardiac Output↗
PubMed1993

Origin and evaluation of depressed inotropism in hypertensive cardiomyopathy.

Left ventricular pressure overload results in the development of left ventricular hypertrophy (LVH) which is considered an adaptive mechanism of the heart to normalize systolic wall-stress. Impairment of both contractility and relaxation occurs, implying that the hypertrophied myocardium is very sensitive to ischaemia, alterations in coronary haemodynamics and to mechanisms incompletely understood. Experimental data from papillary muscles and isolated coronary perfused hearts (renovascular hypertensive rats) demonstrated respectively: a decrease in velocity of shortening, an increase in isometric timing parameters, and an increase in developed pressure. In contrast, the first derivative of left ventricular pressure, normalized to developed pressure, was decreased for large balloon volumes, suggesting an impairment of systolic function at major loading in LVH. In humans, left ventricular systolic dysfunction occurs later (congestive heart failure) when ejection fraction is impaired. Increases in total minimal vascular coronary resistances observed both in humans and in animals could be related to structural and functional alterations in coronary microvessels. Studies of LVH regression under treatment with angiotensin-converting enzyme inhibitors, calcium-channel blockers and beta-receptor blockers have confirmed that only drugs that block the renin-angiotensin system or the sympathetic nervous system are effective in maximizing the reversal of LVH.

Animals↗
PubMed1992

Early hemodynamic results of left ventricular reconstructive surgery for anterior wall left ventricular aneurysm.

To assess the efficacy of left ventricular (LV) reconstruction after aneurysmectomy, 35 consecutive patients with anterior LV aneurysm were studied before and after surgery. Surgical technique was performed by applying a circular patch after aneurysmectomy to maintain a "more physiological" LV cavity. Myocardial revascularization was performed in all but 1 patient concurrently. Global perioperative mortality was 4.8%. LV filling pressure and volumes and regional wall motion were assessed before and after surgery. The major indication for surgery was angina; 8 patients were in New York Heart Association class III/IV. The results showed a significant decrease in end-diastolic volume index (from 120 +/- 55 ml/m2 to 76 +/- 22 ml/m2, p less than 0.001), end-systolic volume index (from 74 +/- 44 ml/m2 to 40 +/- 18 ml/m2, p less than 0.001) and end-diastolic pressure (from 17 +/- 7 mm Hg to 13 +/- 5 mm Hg, p less than 0.05). Ejection fraction significantly increased (from 39 +/- 13% to 49 +/- 15%, p less than 0.001). LV wall motion significantly improved in all but the anterobasal region; the extent of LV asynergy significantly decreased after surgery. Six of the 35 patients had a deterioration of postintervention ejection fraction (from 44 +/- 14% to 34 +/- 9%). They had no reduction in LV volumes and no improvement in wall kinetics. It is concluded that LV reconstruction after aneurysmectomy induces significant early improvement of global and regional LV function in most patients; postoperative functional improvement is mainly related to the increase in inferior LV wall motion.

Female↗
PubMed1992

[Evaluation of trials on regression of atheromatous lesions with hypolipemic drugs].

Experimental studies have demonstrated regression of atheromatous lesions with diet and lipid lowering drugs. In order to confirm these results clinically, reliable angiographic methods of analysis must be developed along two lines: quantitative by consensus between independent "blinded" experts, qualitative by digitalizing radiological images. Given the reproducibility of these methods, a variation of 17 to 20% in the size of the atheromatous plaques should be required to affirm a change. Five studies have been performed in patients with atherosclerosis associated with variable degrees of hyperlipidaemia and compared with a control group. NHLBI type II: 59 out of 146 patients with type II hyperlipoproteinaemia were treated with cholestyramine for 5 years with reduction of the progression of > 50% stenosis but no evidence of regression (6%). CLAS: 80 out of 160 coronary patients were treated with cholestipol and nicotinic acid for 2 years and a reduction of progression and a regression of lesions were observed in 16% of cases. Nikkila: 28 coronary patients with hyperlipidaemia were given clofibrate or nicotinic acid for a 7 year period, stabilising the evolution but with no signs of regression. FATS: 74 of 120 coronary patients with apolipoprotein B concentrations of over 1.25 g/l were given lovastatine-cholestipol or nicotinic acid-cholestipol for 2.5 years: regression of coronary lesions was observed in 32 to 39% of cases depending on the treatment administered. Olsson: reported the same results for femoral atheroma with treatments associating fenofibrate and nicotinic acid: 20% regression and reduction of progression.(ABSTRACT TRUNCATED AT 250 WORDS)

Arteriosclerosis↗
PubMed1991

[Left ventricular hypertrophy and arrhythmia. An aspect of hypertensive cardiomyopathy].

Epidemiological data has established a relationship between left ventricular hypertrophy (LVH) and sudden cardiac death. This relationship is independent. The search for ventricular and atrial arrhythmias in hypertensives confirms a greater prevalence of these arrhythmias in patients with LVH. The mechanism of these arrhythmias is multifactorial: ischemia, subendocardial fibrosis, increased sympathetic tone, electrolyte disturbances, age, and hemodynamic changes may be arrhythmogenic substrates both at the ventricular and auricular levels. The relationship between LVH (marker or cause) and the detected arrhythmias remain obscure. The most sensitive markers of severity seem to be the ECG parameters (LVH with overload), echocardiographic mass (greater than + 20%) and septal thickness (greater than 12 mm). The evolution of arrhythmias with regression of LVH is unknown. Respect of electrolyte equilibrium would seem to be the only unquestioned therapeutic intervention.

Arrhythmias, Cardiac↗
PubMed1991

[Mass and geometry of the left ventricle. Methods of angiographic determination].

Hypertrophy is a myocardial adaptation to pathological conditions of overload and leads to a reduction of cardiac afterload. Angiocardiography (the so-called reference method) allows calculation of mass and volume after opacification of the left ventricle in two orthogonal planes, based on different mathematical models: the area-length method: the left ventricle is assumed to be ellipsoid. The short axis diameter and the volume are calculated from measurements of the area of the left ventricle in the long axis; Simpson's method: the ventricle is divided into sections along its long axis. The diameters of the sections are measured in each incidence. Left ventricular volume is calculated from the area of each section and the distance between two sections; myocardial mass: calculation of the myocardial mass requires measurement of the volumes of the left ventricle with the diameters increased by twice the wall thickness. The accuracy of these measurements depends on several factors: geometrical: true parallelism between the long axis of the ventricle and the planes of projection; influence of the contrast medium in the volume and contraction; this is negligible in the first three systoles; detection of the ventricular contours: this may be manual or automatic and requiring techniques of image digitalization. Therefore, the calculation of ventricular mass is directly related to volume determination, and hypertrophy can only really be quantified by mass/volume or wall thickness/diameter ratios.

Adolescent↗
PubMed1991

[Acute aortic dissecting: contribution of transesophageal echography. Apropos of 10 cases].

The diagnostic value of combined transthoracic (TTE) and transesophageal echocardiography (TEE) was evaluated in 10 consecutive patients with acute dissecting aneurysm of the aorta and compared to aortography (10 cases) and computed tomography (7 cases). TEE seems to be highly superior to TTE because the intimal flap in always seen (versus 4 of the 10 TTEs) and the descending aorta and the entry site are better visualized. TEE is superior to X-ray computed tomography because it shows the direction of the flow in the false lumen (an advantage of a color Doppler), the entry site and aortic regurgitation. In spite of false-positives (1/10), TEE seems to be at least as good as aortography, the most reliable, but highly invasive, technique available. Thus, transesophageal echocardiography, performed at the patient's bedside, appears to be a promising non-invasive tool for diagnosing suspected dissecting aneurysms of the aorta.

Acute Disease↗
PubMed1990

Study of the electrophysiological properties of intravenous bisoprolol in patients with and without coronary artery disease by programmed stimulation.

The objective of this study was to assess the electrophysiological properties of intravenous bisoprolol in patients with and without coronary artery disease (CAD) by programmed stimulation. Sixteen inpatients subjected to an electrophysiological investigation because of dizziness or palpitations were given 10 mg of intravenous bisoprolol after basal measurement and were checked again 15 and 45 min after infusion. Eight patients with CAD (seven males and one female; mean age of 60+/-4 years) and eight patients without CAD (five males and three females; mean age of 59+/-4 years) were investigated after washout of prior antiarrhythmic drugs. For coronary patients, the CAD was documented by a history of myocardial infarction or by a confirmatory coronary arteriography. Main outcome measures were parameters of invasive electrophysiological exploration, with measurement of conduction intervals at rest and during pacing and of refractory periods by means of extrastimulus technique. No significant difference was noted at baseline between the two groups except for CSNRT. After infusion of 10 mg of bisoprolol, with the exception of CSNRT (increased in the group without CAD), no significant differences were noted on comparison between coronary and noncoronary patients. Bisoprolol significantly increased the sinus cycle length, SACT, and FRP of the atria. Regarding atrioventricular nodal conduction, bisoprolol significantly increased the AH 100, ERP, and FRP and significantly decreased the Wenckebach point. In the right ventricle, bisoprolol moderately, but significantly, decreased the corrected QT and induced a small, temporary, significant increase in ERP. Bisoprolol appears to be a very potent beta-blocker that is well tolerated at an intravenous dose of 10 mg. Its depressant effects concern mainly the atrial function and the nodal conduction, without significant differences between the two groups of patients. The decrease in QTc may be a favorable aspect regarding its electrophysiologic tolerance especially in the acute phase of myocardial infarction.

Adrenergic beta-Antagonists↗
PubMed1990

[Reconstruction of the left ventricle by circular endoventriculoplasty with septal exclusion].

Since 1984 the authors have developed a technical modification of left ventricular surgery after myocardial infarction. The principle is to reorganise the contractile muscle in a circumferential manner by excluding the fibrous akinetic parts of the interventricular septum. The operation consists of implanting sutures distally then resecting the exteriorized fibrous zones and finally mobilising the scarred endocardium in the zones inaccessible to resection (septum and the base of the anterior and posterior papillary muscles) up to the limits of the viable myocardium. A patch of septal endocardium or dacron lined with pericardium is sutured in the contractile muscular zone. One hundred and fifty patients have been operated for cardiac failure (37%), angina (40%) or arrhythmias (10%). One third of patients required intra-aortic balloon pumping in the preoperative period. Myocardial revascularisation was associated in 75% of cases. Surgery was performed as an emergency in 33 cases (25% mortality); in the remaining 117 cases the mortality was 5%. Postoperative control assessment (115 immediate postoperative and 60 one year controls) showed the left ventricular geometry to be almost normal and the global ejection fraction to have increased by an average of 17%. This technique of left ventricular remodelling with septal exclusion enables the surgeon to perform a more physiological repair in patients without cardiac failure and to extend the surgical indications in patients with cardiac failure.

Arrhythmias, Cardiac↗
PubMed1990

[Enoximone, vasodilator and/or inotropic agent in congestive cardiac insufficiency? Hemodynamic and ventriculographic study of 20 cases].

The aim of this study was to document the effects of enoximone in congestive cardiac failure. The haemodynamic data (aortic pressure, pulmonary pressures, left ventricular pressure, cardiac output, isovolumic contractility index: Vmax) and left ventricular kinetics of 20 patients with dilated cardiomyopathy (11 ischemic and 9 idiopathic in Stages III or IV of the NYHA Classification before recompensation) were recorded under basal conditions, after 30 minutes infusion of dobutamine (10 micrograms/kg/mn) and after 3 hours infusion of enoximone (total dose: 3.6 mg/kg). The two drugs had an equivalent inotropic effect: ejection fraction + 4 +/- 22% with dobutamine and + 16 +/- 39% with enoximone; Vmax increased from 1.53 +/- 0.5 c/sec to 2.49 +/- 0.8 c/sec with dobutamine and to 1.82 +/- 0.5 c/sec with enoximone. Enoximone induced a greater degree of vasodilation (systemic resistances - 14 +/- 21% with dobutamine and - 21 +/- 27% with enoximone) and a more pronounced fall in ventricular filling pressures (- 35 +/- 42% with dobutamine and - 58 +/- 24% with enoximone). Enoximone was less effective than dobutamine in increasing cardiac output (+ 46 +/- 42% with dobutamine and 16 +/- 33% with enoximone) and stroke volume (+ 23 +/- 47% with dobutamine and + 2 +/- 41% with enoximone). This difference in efficacy may be explained by the major reduction in ventricular preload which enoximone induced after that observed with dobutamine. "Responders" (12 patients) had basal cardiac outputs of less than 2.3 l/mn/m2; the peripheral vasodilatation caused by enoximone was greater. Finally, the reduction in left ventricular end diastolic pressure and the increase in Vmax were significantly less in the 11 patients with ischemic cardiomyopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Left ventricular aneurysm: a new surgical approach.

Since 1984, we have used a circular patch to reconstruct the left ventricle ("endoventricular circular plasty") in order to maintain a more physiologic cavity. This technique has three theoretical advantages over standard linear closure of the left ventricle (LV). First, it allows exclusion of the septal akinetic segment of the LV. Secondly, circular reorganization of the remaining LV muscle avoids the restraint caused by the linear suture closure and achieves a more physiologic LV cavity. Thirdly, circular plasty using the patch allows a complete resection of aneurysmal segments including resection of extensive subendocardial scar tissue, when appropriate, without critically compromising the cavity size. The technique involves the following steps: --Resection of dyskinetic or akinetic LV free wall and thrombectomy when indicated. --A dacron patch lined with pericardium is secured at the junction of the endocardial muscle and scarred tissue, thereby excluding non contractile portions of the LV and septum. --Myocardial revascularization is performed as indicated with particular attention paid to revascularizing the proximal left anterior descending segment. The group of patients forming this study includes 130 cases of LV reconstruction since 1984. The three main indications for surgery were angina (40%), cardiac failure (35%), arrhythmias (10%). There have been 8 hospital deaths, 4 late mortalities related to recurrence of cardiac failure in this group.(ABSTRACT TRUNCATED AT 250 WORDS)

Heart Aneurysm↗
PubMed1989

[Electrophysiologic effects of intravenous 3-hydroxy-dihydroquinidine (LNC-834) in man].

The object of this study was to determine the electrophysiological effects of 3-hydroxy-dihydroquinidine (3-OH-HQ) in man. The electrophysiological parameters were measured in 12 patients before and after intravenous infusion of 5 mg/kg of 3-OH-HQ in 15 minutes. The mean plasma concentrations obtained varied from 2.4 +/- 1.1 mg/l at the 20th minute to 0.9 +/- 0.3 mg/l at the 60th minute. In these concentrations, 3-OH-HQ did not cause hypotension or affect the heart rate and nodal conduction. It did, however, prolong infra-hisian and intraventricular conduction and ventricular repolarisation from the 20th to the 60th minute after starting the infusion. The peak effect was observed at the 20th minute (+19 +/- 3.4 ms; +14.6 +/- 3.5 ms; and +44.5 +/- 6.6 ms, respectively). The 3-OH-HQ increased the effective atrial and ventricular refractory periods at the 30th minute (+21.8 +/- 5.5 ms and +22.3 +/- 7 ms, respectively). However, the ventricular effect only was discernable at the 60th minute. These effects are quantitatively comparable to those of quinidine. Extrapolation of these results to the effects of chronic oral treatment should be reserved as the therapeutic zone of this new molecule has not yet been determined.

Aged↗
PubMed1989

[Data of programmed ventricular stimulation in left ventricular hypertrophy of hypertensive origin].

Various studies have established the increase of sudden death in hypertensive patients with left ventricular hypertrophy (LVH). In order to specify its most important factors, an electrophysiological study consisting of Holter recording (HR) and programmed ventricular stimulation (PVS), was performed in 24 patients with hypertension: 12 with LVH and 12 without LVH, on ultrasonography. In all patients, coronary angiography was normal. The results are the following: 1) LVH increases the ventricular vulnerability, this arrhythmogenic substrate and its stability are explored by PVS; 2) HR and PVS are not correlated, therefore HR does not explore the arrhythmogenic substrate of LVH, but rather the potential triggering factors of severe rhythm disorders; 3) it has not been possible to evaluate the role of the autonomous nervous system in this study; 4) finally, a significant correlation was found between the degree of anatomical hypertrophy of the LV and the duration of the interval AH.

Adult↗
PubMed1988

Clinical study of an LH-RH agonist (ICI 118.630, Zoladex) in the treatment of prostatic cancer.

Eighty patients with prostatic cancer have been treated with an LH-RH analogue (Zoladex). Ten had no metastasis, and hormone therapy was used as an induction treatment before curative radiotherapy. The others had metastatic disease and, in some cases, had already received some form of endocrine therapy. Patients received a monthly injection of Zoladex (3.6 mg). No progressive disease was noted among patients with nonmetastatic tumors; of the patients with metastases, those who were previously untreated had a higher response rate (14.8% complete response) and longer progression-free and overall survival. Toxicity was mild in spite of two cases of disease flare.

Aged↗
PubMed1988

Left ventricular hypertrophy and ventricular dysrhythmic risk in hypertensive patients: evaluation by programmed electrical stimulation.

Left ventricular hypertrophy in hypertensive patients is associated with an increased prevalence of ventricular arrhythmias. Twelve patients with left ventricular hypertrophy assessed by M-mode echocardiography and 12 without left ventricular hypertrophy underwent an electrophysiological study with programmed electrical stimulation. The patients with left ventricular hypertrophy had a prolonged infranodal conduction time which correlated closely with left ventricular mass (r = 0.71; P less than 0.001). Programmed electrical stimulation initiated more intraventricular re-entry and unsustained ventricular tachycardia in the group with left ventricular hypertrophy than in the control group, although sustained ventricular tachycardia was never induced. We conclude that ventricular vulnerability is increased in hypertensive patients with left ventricular hypertrophy, especially in those who show electrocardiographic evidence of left ventricular hypertrophy.

Arrhythmias, Cardiac↗
PubMed1988

[Ablation of atrio-ventricular conduction by fulguration of the His bundle. Proposal for a simplified technic. Apropos of 70 cases].

Between 1982 and 1987, 70 patients (32 men, 38 women, aged from 45 to 93 years) underwent catheter ablation of His bundle and were followed up for more than 3 months. The disorders treated were atrial fibrillation, flutter of tachycardia (62 cases), junctional tachycardia (7 cases) and refractory atrial extrasystoles (1 case). The overall results were: early failure in 1 case, late death in 3 cases, persistent high degree AV block in 53 cases (75 p. 100), 1st degree AV block in 9 cases (12 p. 100) and failure in 8 cases (13 p. 100). Two techniques were used. In the first 30 patients ablation was performed by tri- or quadripolar catheters with electrodes 10 mm apart (USCI 2943/2854) and localization by an unipolar electrode connected to the negative pole of the defibrillator. The mid-term results in this series were: complete AV block in 20 cases (66 p. 100), partial AV block in 5 cases (17 p. 100) and failure in 17 cases (17 p. 100). In the last 40 patients localization was bipolar and ablation was obtained with simultaneous bipolar leads taken from a Josephson catheter with electrodes 5 mm apart (USCI 8567); the two electrodes recording the highest His bundle potential were connected to the negative pole of the defibrillator. The results in these series were: complete AV block in 33 cases (82 p. 100), partial AV block in 4 cases (11 p. 100) and failure in 3 cases (7 p. 100). Although the two series were not exactly similar, it seems permissible to recommend the second, more convenient technique.

Aged↗