Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Invasive cardiac catheterisation remains the reference technique for the evaluation of the effects of vasodilator drugs in cardiac failure. The arterial, venous or mixed site of action can be determined. Venous vasodilators induce a fall in left ventricular end diastolic volume (EVD), left ventricular end diastolic pressure (EDP), and stroke volume (SV). Arterial vasodilators decrease left ventricular end systolic pressure (ESP), end systolic volume (ESV) and increase the stroke volume. Mixed vasodilators associate the effects of both, leading to a fall in left ventricular filling pressures and an increase in SV. It is not always easy to determine the exact site of action of a given vasodilator drug. Arterial vasodilatation can only be confirmed when peripheral arterial resistances and systemic blood pressure decrease simultaneously. Venous vasodilatation can only be formally confirmed by using other techniques such as pethysmography. Hemodynamic investigations have other fundamental objectives in the evaluation of the effects of a vasodilator, especially the demonstration of possible associated positive inotropic effects. This would be relatively easy in the case of a venous vasodilator which induces an increase in SV but more difficult in the assessment of an arterial vasodilator. Studying the distribution of regional blood flow after the administration of a vasodilator is another important objective of cardiac catheterisation. Although coronary flow can be studied properly, the hemodynamics of other regions can only be assessed approximatively. The phenomenon of tolerance at an early or late stage of vasodilator therapy can also be demonstrated by hemodynamic monitoring.
Arch Mal Coeur Vaiss 1990 Mar
PMID:[Methods for evaluating vasodilator agents in cardiac failure]. 211 89

This Doppler echocardiographic study of patients with a dual chamber pacemaker was undertaken to assess the changes in mitral and aortic flow induced by passing from the double stimulation to the atrial detection mode. Thirteen patients totally dependent on ventricular pacing were examined and mitral and aortic blood flow recorded by pulsed wave Doppler. The chronology of left atrial contraction as assessed by the Doppler mitral A wave was measured with respect to the ventricular stimulation. The A wave was recorded on average 177 ms after the right atrial stimulation artefact. For an average AV delay of 168.8 ms and an identical pacing frequency, the passage from the double stimulation to the atrial detection mode led to left atrial contraction occurring on average 70 ms earlier with respect to ventricular stimulation, reflecting prolongation of the programmed AV delay related to the delay in detection of the sinus atrial wave. This earlier atrial systole shortened the total duration of mitral flow from 363 to 317 ms, decreased the early diastolic mitral flow and increased the atrial end diastolic flow; the stroke volume and cardiac output calculated from the aortic velocity time integral decreased significantly from 73 +/- 11 ml to 67 +/- 10 ml and 5.4 +/- 1.11/mn to 4.9 +/- 1.01/mn respectively. The initial parameters were restored (average 74 +/- 9 ml and 5.5 +/- 1.11/mn respectively) when the AV delay in the atrial detection mode was reduced by a value close to that of the calculated increase.(ABSTRACT TRUNCATED AT 250 WORDS)
Arch Mal Coeur Vaiss 1990 Jun
PMID:[Doppler echocardiographic study of hemodynamic changes of double stimulation mode and atrial detection in patients with dual chamber pacemaker. Value of hysteresis of the atrioventricular delay]. 211 56

Resting and stress radionuclide angiography was performed before and, on average, one year after surgery for adult aortic stenosis in 26 patients. The left ventricular ejection fraction, ventricular volumes, left ventricular stroke volume and peak velocity of ventricular filling were studied under basal conditions and at the peak of exercise. Right and left heart catheterisation and coronary angiography were performed before surgery with determination of the conventional indices of left ventricular function. Investigations were completed by pre and postoperative echocardiography. The same procedures were carried out in a control population of the same age. Before surgery, hemodynamic adaptation to exercise, judged by the change in left ventricular stroke volume, solicits the passive properties of the left ventricle: the left ventricular stroke volume increases by an increase in the end diastolic volume. In the control group, the increase in stroke volume is obtained by a decrease in end systolic volume, that is to say by increasing systolic shortening. The peak velocity of ventricular filling increases on exercise but to a lesser degree than in the control population. After surgery the hemodynamic adaptation to exercise results from an improved systolic shortening of the left ventricle but also from an increase in end diastolic volume. The peak velocity of left ventricular filling increases with respect to the preoperative values but remains less than that observed in the control population. No relationship was observed between the hemodynamic adaptation to exercise, the peak velocity of ventricular filling and myocardial mass whichever method was used for calculating the latter parameter.(ABSTRACT TRUNCATED AT 250 WORDS)
Arch Mal Coeur Vaiss 1990 Dec
PMID:[Postoperative course of systolic and diastolic indices of left ventricular function in aortic valve stenosis in adults. Exercise test with radionuclide angiography]. 212 9

The aim of this study was to measure the changes in mitral and aortic blood flow induced by rate changes and different atrioventricular intervals in dual chamber pacemaker patients. Ten totally pacemaker dependant patients were studied under basal conditions, in double atrial and ventricular stimulation mode, by pulsed Doppler recordings of mitral and aortic flow, at three different pacing rates (80, 100 and 120/mn) and with three different atrioventricular intervals at each rate (short, 90 or 115 ms; medium, 165 or 190 ms; and long, 240 ms). The increase in pacing rate and prolongation of the atrioventricular interval significantly shortened the duration of mitral flow. Increasing the pacing rate induced a significant fall in stroke volume measured from the aortic flow. The optimal atrioventricular interval tended to shorten when the pacing rate was increased; a long atrioventricular interval had a deleterious effect on stroke volume compared with medium and short atrioventricular intervals; however, the difference between the short and medium atrioventricular intervals was not statistically significant even at 120 mn. These observations emphasise the hemodynamic advantages of shortening of the atrioventricular interval of dual chamber pacemakers when the pacing rate increases.
Arch Mal Coeur Vaiss 1990 Dec
PMID:[Doppler echocardiographic study of mitral and aortic flow at various rates and atrioventricular intervals in patients with dual chamber pacemakers]. 212 18

Two techniques of cerebral revascularization have been developed: angioplasty of the brachiocephalic vessels (204 cases) and local intra-arterial fibrinolysis in the carotid region (26 cases). Angioplasty appears to be the treatment of choice for inflammatory and atherosclerotic stenoses of the main trunks arising from the aortic arch (82 cases). Stenoses of the origin of the vertebral artery are not often ulcerated and may also be treated by angioplasty (42 cases) as long as the stenosis has been recognized as the cause of vertebral insufficiency symptoms. Among the stenoses of the carotid bifurcation, recurrent postsurgical ones are rather easily treated by angioplasty, particularly when they are recognized early by Doppler examination. Postsurgical and inflammatory stenoses do not require cerebral protection during angioplasty. Conversely, cerebral protection is mandatory for treatment of atherosclerotic stenoses because of the risk of embolic detachment of particles in to brain circulation. A new triple coaxial catheter system has been designed which seems so far to be very efficient. Local intra-arterial fibrinolysis in the carotid region is selected on the basis of clinical signs, the delay after onset and results of CT and complete cerebral angiographic workup. A classification into three topographic groups is proposed. The group at highest risk of post-fibrinolysis hemorrhage is the one with occlusion of the lenticulostriate arteries. It would seem hazardous to undertake fibrinolysis in a patient of this group unless it can be started no later than 4 or 5 hours after clinical onset. Rapid transportation of stroke patients is recommended so that CT and complete arteriography may be performed before deciding whether to use fibrinolytics.
J Mal Vasc 1990
PMID:[Intravascular technics of cerebral revascularization]. 214 82

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)
Arch Mal Coeur Vaiss 1990 Sep
PMID:[Enoximone, vasodilator and/or inotropic agent in congestive cardiac insufficiency? Hemodynamic and ventriculographic study of 20 cases]. 214 34

In our department, percutaneous balloon valvuloplasty has become the routine treatment of aortic valve stenosis in adults. We report here the results obtained in 245 consecutive patients. The patients' age varied between 30 and 98 years (mean 74 +/- 11 years), 77 of them (31 p. 100) being 80 years' old or older. The initial peak to peak ventriculo-aortic gradient was 72 +/- 25 mmHg and the aortic valve area was 0.53 +/- 0.17 cm2. After dilatation the gradient was reduced to 29 +/- 14 mmHg (p less than 0.001) and the aortic valve area was increased to 0.95 +/- 0.33 cm2 (p less than 0.0001). The aortic valve area was increased by 100 p. 100 or more in 83 patients (34 p. 100) and by less than 25 p. 100 in only 17 patients (7 p. 100). The ventricular ejection fraction rose slightly but significantly from 48 +/- 18 p. 100 to 51 +/- 17 p. 100 (p less than 0.01). One patient developed massive regurgitation and had to undergo semi-emergency surgery. The experience acquired and the use of better catheters enabled us to improve these results by almost doubling the number of patients whose aortic valve area became 1 cm2 or more and by reducing by half those whose aortic valve area remained 0.7 cm2 or less. Three patients aged 82, 91 and 98 respectively died, and there was one cerebral vascular accident in the catheterization room. Nine patients (4 p. 100) died in hospital during the following days.(ABSTRACT TRUNCATED AT 250 WORDS)
Arch Mal Coeur Vaiss 1989 Jan
PMID:[Treatment of acquired aortic stenosis in adults by percutaneous valvuloplasty with balloon catheterization. Experience of 245 cases]. 249 65

Cardiac output and haemodynamic volumetric values (stroke volume, stroke index, left ventricular end-diastolic volume, blood volume, mean corpuscular volume and packed red cell volume) were measured in a population of 69 very old subjects (80 to 102 years) whose heart was regarded as normal on the basis of criteria determined, by radiocardiography and radionuclide ventriculography. These harmless and non-invasive techniques provided reference values in subjects of a seldom explored age group. Altogether, these values were lower than those of younger adults, and they decreased with age. Their reliability is due to the fact that they were obtained by true measurement and not by extrapolation of results observed in adults.
Arch Mal Coeur Vaiss 1989 Apr
PMID:[Measurement by isotope study of the cardiac output in the elderly]. 250 Sep 11

Stroke-Prone spontaneously hypertensive rat strain (SHR-SP) always develops hypertensive retinopathy. The aim of the present work was to study the activity of a new antihypertensive drug, a synthetic furopyridine: cicletanine, in retinal hypertensive morphological lesions. The experiment was performed in 39 rats SHR-SP/A3N Iffa Credo, 11 weeks old, divided into 3 groups: group 1 was the control group, groups 2 and 3 were orally treated with cicletanine (respectively 100 and 150 mg/kg). All the rats had free access to tap water containing 1 p. 100 NaCl. During 6 weeks, blood pressure, body weight and survival were recorded, then all the rats were sacrificed. The eyes were removed, the posterior pole collected and fixed with Trump liquid for transmission election microscopy. In the SHR-SP control group, each layer showed neural body and/or process lesions: in the ganglion cell layer, some ganglion cells realized cytoid bodies corresponding to a lysed cell with nucleus degeneration, most of the axons were destroyed. In the inner and outer plexiform layers, most of the contacts between processes were lost because of fibrinous deposits. Numerous synapses were destroyed in the outer plexiform layer. These findings might explain the numerous dense bodies in the inner rod segment and the vesiculation of the rod outer segment. The capillaries showed markedly hypertensive lesions. Whereas, in both treated groups, rare and animal lesions were observed. The fact that these lesions were so few and so unimportant after 6 weeks of treatment, as well as for the photoreceptors which remained unimpaired, is closely related to cicletanine therapy, since it was so even though the treatment had been started with an already high blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)
Arch Mal Coeur Vaiss 1989 Jul
PMID:[Malignant hypertensive retinopathy in spontaneously hypertensive stroke-prone rats. Effect of treatment with cicletanine]. 251 Jun 62

The author reviews the haemodynamic changes in response to exercise, autonomic nervous blockade and food take, Left ventricular (LV) volume changes are most pronounced during mild exercise, whereas an increase in heart rate is the primary determinant for the increase in cardiac output during mild to heavy exercise. After autonomic blockage the heart possesses intrinsic mechanisms to maintain cardiac output during submaximal exercise. LV end-diastolic dilatation results in a preserved stroke volume despite reduced contractility. At rest cardiac output increase postprandially mostly because of a greater stroke volume accomplished by LV end diastolic dilatation, whereas heart rate is only slightly increased. These changes are unique to humans, and are thought to take place secondary to the action of vasoactive peptides from the gastrointestinal tract involved in digestion. The LV volume changes are minimized after autonomic nervous blockade. During exercise cardiac output in also higher after food intake due to a rise in both stroke volume and heart rate, but only in the innervated heart. Thus, most of the haemodynamic changes recorded after food intake are under the influence of the autonomic nervous system.
Arch Mal Coeur Vaiss 1989 Aug
PMID:Intrinsic heart function and food intake. 251 Jun 92


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>