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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Milrinone is an inotropic agent of the phosphodiesterase inhibitor family. In common with all molecules of this class it has both positive inotropic and vasodilator effects. The haemodynamic effects of 3 dosages of milrinone were studied in 25 patients with low output states after open heart surgery. The low cardiac output was defined as a cardiac index of less than 2.5/min/m2 and pulmonary capillary pressures greater than 8 mmHg. Milrinone was administered as a bolus of 50 micrograms/kg/min over 10 minutes followed by a continuous infusion for at least 12 hours. Six patients were given 0.375 micrograms/kg/min, six patients 0.5 micrograms/kg/min, and 13 patients 0.75 g/kg/min. A significant increase in cardiac index was observed but without any difference between the 3 groups. The heart rate and stroke volumes were increased. There was a mild reduction in systemic blood pressure with a decrease in systemic arterial resistances which returned to almost normal values. Left and right filling pressures did not decrease significantly from the initial values until the end of the bolus injection. Indirect measurements of myocardial oxygen consumption showed an increase in this parameter. There were no changes in blood gas concentrations. The treatment was stopped in only one patient because of peripheral vasodilation. Two patients developed supraventricular tachycardia of no consequence. Milrinone may therefore be proposed as treatment of first intention of low cardiac output states after open heart surgery. It is associated with a mild vasodilatory effect. Improved myocardial function is observed providing attention is paid to vascular filling. None of the maintenance doses used after the bolus injection was shown to be more effective than the others.
Arch Mal Coeur Vaiss 1991 Nov
PMID:[Hemodynamic effects of milrinone in the treatment of cardiac insufficiency after heart surgery with extracorporeal circulation]. 176 24

Ultrafast computed tomography and magnetic resonance imaging are two new methods of cardiac imaging. Measurements of left ventricular volume (end-diastolic, end-systolic volume, stroke volume) and mass have been validated with both methods. The calculations are independent of the geometric shape of the ventricle. Although regional analysis is difficult because of the complex movement of the left ventricle in the tomographic cuts, these methods present a number of advantages: excellent temporospatial tomographic resolution, approximately the same in all dimensions, appreciation of endocardial movement from an epicardial centre, the potential to record their transform spatial data in 3 dimensions from initial planar acquisition. However, all potential regional measurements are still being validated as they are operator-dependent and require visual identification and manual tracing of the cardiac contours or local infrastructures which affect the results of these techniques which are still relatively little used in cardiac imaging. In the context of clinical evaluation, these relatively non-invasive methods will become extremely accurate in the appreciation of parameters of left ventricular geometry and function. They will become very useful in the determination of the myocardial effects of drugs, surgery or other interventional procedures in different models of cardiac disease.
Arch Mal Coeur Vaiss 1991 Dec
PMID:[Mass and geometry of the left ventricle. Contribution of ultrafast computed x-ray tomography and magnetic resonance imaging]. 179 28

The geometry of both the infarcted and non-infarcted zone of the left ventricle changes after myocardial infarction. Two mechanisms are involved: expansion of the infarcted zone and secondary dilatation of the non-infarcted zone. The necrosed area undergoes an inflammatory reaction followed by fibrosis which end up as a sca within a period of a few days to a few weeks. During this period if fibrous scarring the infarcted, thinned myocardium undergoes progressive expansion which starts in the first hours of the myocardial infarction. The loss of left ventricular systolic function related to the infarct and volumic overload created by expansion of the infarct influence the secondary development of dilatation of the non-infarcted zones. This dilatation results in restoration of left ventricular stroke volume but at the price of increased wall stress, which itself induces compensatory wall hypertrophy. These phenomena are more pronounced when the initial infarction is extensive and if they are sustained, they result in definitive myocardial failure. Several factors influence remodeling: the size of the infarct, arterial patency, wall stress and the quality of the scarring process itself. Therapeutic interventions of each of these factors can influence the remodeling. Limitation of infarct size by thrombolytic therapy, arterial revascularisation, even when performed late, seem capable of limiting expansion of the necrosed zone. Pharmacodynamic intervention of left ventricular afterload also affects ventricular remodeling. Nitrate derivatives, vasodilator therapy in general and converting enzyme inhibitors have been shown to be effective.
Arch Mal Coeur Vaiss 1991 Dec
PMID:[Physiopathology of left ventricular remodeling after myocardial infarction]. 183 20

The aim of this study was to detect possible atrial electrophysiological abnormalities in patients with unexplained embolic cerebrovascular accidents without overt atrial arrhythmias. This group was compared with normal controls and a group of patients with paroxysmal atrial fibrillation. Sixty-six patients were studied: Group I normal controls (N = 20); Group II patients with CVA (N = 26) and Group III, patients with paroxysmal atrial fibrillation (N = 20). Each group was divided into 2 subgroups according to age (over and under 45 years). The following parameters were taken into consideration: parameters correlated to atrial excitability (effective and functional refractory periods, adaptation of these refractory periods, intraatrial conduction--A1 and A2, S1A1, S2A2 intervals--, index of latent vulnerability); provocative testing by the extrastimulus technique; classical indices of atrioventricular conduction and sinus node function. In subjects over 45 years of age, the effective refractory periods were shorter in Group III (214 +/- 33 ms) and II (214 +/- 32 ms) than in the control Group I (248 +/- 21 ms), p less than 0.01. This difference was not apparent in younger patients. Inadaptation of the refractory periods was demonstrated equally in Groups II and III in all ages whilst the control subjects showed normal adaptation, p less than 0.05. Intraatrial A1 and especially A2 conduction was significantly prolonged in Group III (94.5 +/- 24 ms) and II (87 +/- 14 ms) compared with the control group (69 +/- 8 ms), p less than 0.01, especially in younger subjects.(ABSTRACT TRUNCATED AT 250 WORDS)
Arch Mal Coeur Vaiss 1991 Jul
PMID:[Atrial electrophysiological study of unexplained cerebrovascular disorders]. 192 14

The aim of this study was to assess the validity of mitral valve blood flow measured by pulsed Doppler echocardiography (PDE) with the sample volume positioned at the tips of the mitral leaflets. Thirty patients with a mean age of 38.4 years underwent calculation of transmitral blood flow: by Touche's method (A) in which the mitral orifice is assumed to be an ellipse with a constant long axis equal to the diameter of the mitral annulus and a variable short axis equal to the distance between the mitral leaflets measured on the M mode recording. The velocities are recorded by PDE with the sample volume at the tips of the mitral leaflets. The instantaneous cardiac output is equal to the surface multiplied by the instantaneous velocity. The integration of the instantaneous outputs throughout the whole of diastole by a computer programme provides the stroke volume; by a simplification of this method (B) which considers the short axis of the mitral ellipse to be constant and equal to the mean mitral valve leaflet separation measured from the M mode recording, and; by Hoit's method (C) which calculates mitral valve surface area from the M mode recording alone. The transmitral blood flow was calculated by these three methods and compared to the classical PDE aortic cardiac output measurement during the same examination, the accuracy of which has been previously demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)
Arch Mal Coeur Vaiss 1991 Jul
PMID:[Determination of transmitral blood flow by pulsed echodoppler. Correlation with aortic blood flow in 30 patients]. 192 15

Progress in neuroimaging has led to a considerable change in our knowledge of cerebral venous thrombosis (CVT). Together with a series of 76 cases, a review of literature is presented. CVT is a far from negligible variety of stroke. It may occur at any age and despite numerous causes (nowadays mostly non infective), the proportion of cases of unknown aetiology remains around 25%. Superior sagittal sinus and lateral sinus are the most frequently involved, often associated with cortical vein thrombosis. Cavernous sinus thrombosis remains the most common form of septic thrombosis. Thrombosis of the galenic system and of cerebellar veins are uncommon. The clinical picture is extremely variable with a mixture of focal signs (deficits or seizures) and symptoms of raised intracranial pressure. The mode of onset is also variable, over hours, days, weeks or months. The presentation can thus be very misleading, simulating an arterial stroke or an abscess, an encephalitis, a tumor or a pseudo-tumor cerebri. CT scan is crucial to rule out other conditions and angiography to confirm the diagnosis of cerebral venous thrombosis. MRI is very performing since it visualizes the thrombus itself and allows a non invasive follow up. Most cases have a benign course but mortality is still around 30% in infective cases and 10% in non infective ones. Although it has long been debated, the benefit of anticoagulant (heparin) is now well established.
J Mal Vasc 1991
PMID:[Cerebral venous thrombosis. Report of 76 cases]. 194 Jun 50

Hypertension is a condition which demonstrates the relationship between the properties of the left ventricle and arterial system. The spectrum of aortic impedence expresses the principal factors which oppose LV ejection into the initial aorta: 1) capacitive forces related to the viscoelastic properties of the arterial wall, directly proportional to its rigidity, 2) forces of inertia which increase with the acceleration of the blood and which are inversely proportional to the aortic cross sectional area, 3) reflection. With respect to a stroke volume which is usually normal, hypertension is characterised by: 1) an increase in mean aortic pressure (MAP), 2) with respect to the increase in MAP, an increase in systolic, late systolic and differential pressures. These changes in the level and morphology of aortic pressure are due to: a) the increase in systemic arterial resistances, a continuous expression of the spectrum of the module, b) an increase in the elastic forces (increased rigidity of the aorta related to increased pressure and structural wall changes) usually insufficiently compensated by a decrease in the inertial forces (aortic dilatation), c) an earlier return of the reflected pulse wave, well before the end of the anterograde wave. Overall, there is a relationship between the mass, the geometry (concentric hypertrophy) and pump function of the left ventricle and the properties of the arterial system expressed in terms of pulse wave velocity, characteristic impedence or the late systolic pressure/stroke volume ratio. The relationship is much closer than that of the properties of the LV and aortic pressure.(ABSTRACT TRUNCATED AT 250 WORDS)
Arch Mal Coeur Vaiss 1991 Sep
PMID:[Properties of arteries, cardiac function and structure in chronic hypertension]. 195 86

Echocardiographic measurement of left ventricular mass has provided a way of evaluating the undesirable effects of high blood pressure on the heart in the same way as for obesity, excess salt intake and blood hyperviscosity. Recently, the left ventricular mass was shown to correlate (r = 0.81) with the hemodynamic stimuli of blood pressure, stroke volume and left ventricular contractility. Prospective trials at Cornell and Framingham indicate that left ventricular mass is a powerful predictive factor of the risk of complications in hypertension. In the first of these trials, we demonstrated in a 5 year follow-up study of 140 men with uncomplicated hypertension that the incidence of death, myocardial infarction or angina requiring myocardial revascularisation, was four times greater in patients with increased left ventricular mass and that this association was independent of the blood pressure levels. Then, in a 10 year follow-up study of hypertensive patients of both sexes, we established that the left ventricular mass was the most powerful predictive factor of mortality and morbidity and that this was so marked (15% death rate in subjects with LVH vs 1% in subjects with normal left ventricular mass--p less than 0.00001--, cardiovascular accidents in 26% of subjects with LVH compared with 12% in subjects with normal left ventricular mass--p less than 0.0001) that only left ventricular mass and age were independant predictive factors of morbid events in multiple variable analysis. In the Framingham study, the frequency of coronary events in a 4 year follow-up period of healthy subjects from the original cohort (average age 69 years) was significantly related to the left ventricular mass and independent of other risk factors.(ABSTRACT TRUNCATED AT 250 WORDS)
Arch Mal Coeur Vaiss 1990 Dec
PMID:[Relationship between left ventricular mass and prognosis of arterial hypertension]. 208 Aug 92

The use of an original ultrasonic transducer holder has made possible the recording of M mode and 2D echocardiography during exercise. Left ventricular function was studied during upright bicycle exercise in two groups: 10 trained athletes (Group A) and 10 normal subjects (Group B). All were 20 years of age. Satisfactory echocardiograms were obtained up to a mean heart rate of 180/mn which corresponded to an average work load of 180 W in Group B and 300 W in Group A. The cardiac output was comparable in the two groups up to a 180 W load, but in Group A a lower HR was compensated by a larger stroke volume (SV). The increase in SV in Group A was related to a greater LV end-diastolic dimension (LVEDD) during exercise, whereas the ejection fraction increased less than in the control group. During very strenuous exercise (Group A only) further increases in cardiac output were related mainly to an increased heart rate and to a lesser degree to increased LVEDD and ejection fraction.
Arch Mal Coeur Vaiss 1990 Feb
PMID:[Exercise echocardiography and study of the left ventricle in sportsmen during exertion]. 210 59

Cardiac output was measured simultaneously by pulsed Doppler echocardiography and thermodilution in 22 patients, 18 of whom also underwent atrial pacing at different rates to give a total of 42 different measurements. The aortic diameter was measured firstly at the aortic ring at the level of insertion of the aortic cusps and then at the point of maximum separation of the valve cups in the left parasternal long-axis view. The aortic velocities were recorded in the apical 5-chamber view immediately below the level of the aortic valve. The correlations obtained at the aortic ring (R1) and at the point of maximum separation of the valve cusps (R2) were 0.77 (y = 0.67x + 1.17: standard error = 0.81 l/m) and 0.64 (y = 0.56x + 0.87; standard error = 1.01 l/mn) respectively. The correlations were much better when 7 technically unsatisfactory measurements were excluded (R2 = 0.76: y = 0.59x + 0.74: standard error = 0.79 l/mn) (R1 = 0.87: y = 0.72x + 1.04: standard error = 0.65 l/mn). THe correlations of stroke volume measured at aortic ring level also improved from r = 0.82 (y = 0.75x + 7.29: standard error = 8.9 ml) to r = 0.89 (y = 0.78x + 7.38: standard error = 7.3 ml). The measurement of cardiac output by pulsed Doppler echocardiography in the aortic root seems to be reliable. The correlations of the values of stroke volume and cardiac output with the thermodilution method are good, allowing detection of beat-to-beat variations of cardiac output, in suitable patients in the hands of experienced operators.
Arch Mal Coeur Vaiss 1990 Feb
PMID:[Noninvasive measurement of cardiac output by pulsed Doppler echocardiography. Correlation with thermodilution]. 210 60


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