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Hemodynamic evaluation during exercise test after acute and chronic ibopamine treatment in patients with congestive heart failure.

The hemodynamic effects of ibopamine (SB-7505), the orally active 3,4-diisobutyryl ester of N-methyldopamine, were studied in 12 patients with congestive heart failure (CHF) after acute dosing, after 20 days of maintenance therapy and after 20 days of drug discontinuation. Acute ibopamine administration increased at rest cardiac index (CI p less than 0.05) and stroke work index (SWI p less than 0.05), and reduced pulmonary capillary wedge pressure (PCWP), mean pulmonary arterial pressure (PAP), total systemic (SVR p less than 0.05) and pulmonary vascular resistance (PVR). These beneficial hemodynamic effects were maintained during supine bicycle exercise: CI and SWI increased more markedly (p less than 0.05) and PCWP increased at a lower extent (p less than 0.05) after ibopamine than on control conditions. PVR exhibited a more pronounced decrease (p less than 0.02), while SVR showed superimposable reductions before and after ibopamine. After chronic therapy with the drug, hemodynamics and left ventricular function again improved during exercise, while withdrawal of ibopamine resulted in hemodynamic deterioration. Heart rate and systemic arterial pressure did not change significantly after the drug. This study demonstrates that ibopamine is able to improve cardiac performance during exercise in CHF patients after both acute and chronic administration.

Adult↗

[ECG and hemodynamic changes during the bicycle ergometry of patients following aortic valve prosthesis].

Interrelated ECG and hemodynamic changes were revealed in an analysis of the results of a bicycle ergometry test (BET) with the recording of ECG in 12 accepted leads and simultaneous impedance rheoplethysmography after Kubichek in 60 patients during rehabilitation for 3 yrs after aortic valve replacement. Impedance-measuring investigation of hemodynamics after physical exercise provided valuable information on causes of ECG changes. More frequent development of ischemic changes during rehabilitation and a variety of hemodynamic causes of changes in physical exercise and in the period of restitution necessitated intermittent BET in patients with a prosthesis of the aortic valve. An increase in voltage of the R wave during BET was combined in most cases with other inadequate hemodynamic reactions and was accompanied by an "ischemic" decrease in ST, and could serve as an additional criterion of threshold exercise.

Adult↗

Poor R wave progression in pure mitral stenosis. Correlation with hemodynamic data.

Poor R wave progression in the right precordial leads has frequently been reported in patients with pure mitral stenosis, but has never been investigated from clinical and hemodynamic points of view. In this work the clinical, electrocardiographic and hemodynamic data of 19 patients (mean age: 49 +/- 8.6 years), with pure mitral stenosis and poor R wave progression (study group) were compared with those of 19 subjects with pure mitral stenosis and normal R wave progression (control group). The age, sex distribution and duration of mitral valve disease were similar in the two groups; also clinical status, i.e. the distribution in the functional classes (NYHA), was similar in the two groups. Mitral valve area was similar in the two groups (1.3 +/- 0.5 vs 1.1 +/- 0.3 cm2), whereas wedge pressure, mean pulmonary artery pressure, systolic and diastolic right ventricle pressures and total pulmonary resistances showed significant lower values in patients with poor R wave progression compared to those with normal R wave progression (P less than 0.05). The hemodynamic variables of left ventricle and the cardiac index were similar in the two groups. In study group patients there was higher prevalence of vertical axis (P less than 0.05). These data indicate that in pure mitral stenosis, clinical status is similar in patients with poor R wave progression and in those with normal R wave progression, whereas in the former there is slighter hemodynamic involvement of the right ventricle.

Adult↗

Long-term hemodynamics following combined heart and lung transplantation in primates.

To assess the long-term hemodynamic consequences of combined heart and lung transplantation, we investigated six rhesus monkeys 2.6 to 4.6 years (mean 4.0) after operation. Total follow-up was 24.0 primate-years. Autotransplantation had been carried out in four animals and allotransplantation in two, and the hemodynamic results were compared with those in three normal monkeys of similar size. Each animal underwent simultaneous right and left heart catheterization and pulmonary arteriography. Hemodynamic measurements were made at three levels of inspired oxygen. Arterial oxygen tension was within normal limits in all animals, and pulmonary artery pressure and pulmonary vascular resistance index did not change significantly with changes in the levels of inspired oxygen. Indices of left ventricular systolic function were normal in all animals. Values for pulmonary artery pressure and pulmonary vascular resistance index were similar in the autograft and normal groups: in the allograft group, the average pressure was 30/17 mm Hg (mean 24) and the index was 5.6 units . m2--both levels significantly higher than normal (pressure was 16/10 mm Hg, mean 13, [p less than 0.001] and index was 2.5 units . m2 [p less than 0.02]). Pulmonary arteriography in the allograft group with the highest pulmonary vascular resistance index (6.1 units . m2) was compatible with pulmonary vascular disease. Pulmonary arteriograms in the remaining eight monkeys were normal. Prolonged survival following combined heart and lung transplantation is possible in primates. Autotransplantation (and probable persisting denervation of the cardiopulmonary axis) does not necessarily result in abnormal long-term hemodynamics. The elevation in pulmonary artery pressure and pulmonary vascular resistance index in the allograft group may be related to previous episodes of pulmonary rejection, infection, or drug reaction.

Animals↗

Acute hemodynamic effects of levothyroxine loading in critically ill hypothyroid patients.

To evaluate the acute cardiovascular effects of high-dose levothyroxine sodium therapy, the hemodynamic findings in eight critically ill hypothyroid patients treated with high-dose levothyroxine were compared with those in two critically ill hypothyroid and nine critically ill euthyroid patients not receiving this therapy. The initial cardiac index was significantly lower in the hypothyroid group; all other hemodynamic values were similar to those of the euthyroid patients. Following levothyroxine loading, the free thyroxine index increased to normal while the free triiodothyronine index was unchanged; all patients had a significant rise in cardiac index but no consistent changes in the other hemodynamic values. Cardiac index correlated positively with heart rate (three patients) and/or stroke volume index (six patients). Increases in stroke volume index correlated with decreases in systemic vascular resistance (five patients), but not with increases in pulmonary artery wedge pressure. No consistent patterns of hemodynamic changes were observed in the untreated hypothyroid or the euthyroid patients.

Aged↗

[Systemic hemodynamics and oxygen metabolism after hepatectomy--effect of hyperdynamic systemic circulatory support on postoperative prognosis].

This study was undertaken to evaluate inotropic effect of dobutamine (DOB) on systemic and hepatic hemodynamics after hepatectomy. Systemic hemodynamics after 70% hepatectomy using mongrel dogs was depressed and oxygen metabolism was disturbed. Whereas in the dogs administrated DOB after hepatectomy, systemic circulation was improved and oxygen metabolism was maintained in a favorable state. In these hepatectomized dogs, hepatic blood flow was increased after administration of DOB. Systemic hemodynamics after hepatectomy in 37 cases of cirrhotic hepatoma was studied. In 15 cases, 3 micrograms/kg/min of DOB was infused i.v.d. after operation, and remaining 22 cases were assessed without DOB as control group. In controls, systemic circulation was depressed and increase of peripheral oxygen demand was compensated by increase of oxygen extraction ratio. Whereas in DOB group, oxygen delivery increased according to hyperdynamic systemic circulation and was followed by increase of oxygen consumption. These favorable hemodynamic results in DOB group reflected on the postoperative prognosis of these patients; 5 of 22 in control group, whereas only 1 of 15 in DOB group died of hepatic failure postoperatively. It is concluded administration of DOB in cirrhotic hepatectomized patients maintained systemic circulation in a hyperdynamic state and this resulted in improvement of postoperative prognosis.

Adult↗

Postural influences on the hemodynamic responses to vasodilating drugs in congestive heart failure.

Supine and upright hemodynamic measurements were performed in 58 patients with congestive heart failure to assess the effects of postural change on the hemodynamic responses to vasodilating drugs. The patient population was divided into three treatment groups and was studied before and after isosorbide dinitrate, nifedipine, or clonidine treatment. When the hemodynamic responses in the upright position were compared with the supine values, isosorbide dinitrate (40 mg orally) evoked a greater reduction in mean systemic blood pressure and stroke volume with augmented increases in heart rate, mean pulmonary artery pressure, and pulmonary vascular resistance while the patient was upright. Nifedipine (10 mg orally) when studied in the upright position caused additional augmentation of cardiac output and stroke volume index with further reduction in total systemic vascular resistance compared with supine values. No position-related changes in hemodynamic measurements were noted with clonidine (0.1 mg orally).

Adult↗

Hemodynamic measurements as aids to choosing drug treatment of essential hypertension.

A hemodynamic measurement system incorporating echocardiography with Doppler, the Evans-Blue method, and sphygmomanometry enables the clinician to estimate cardiac output, blood volume, cardiac contractile force, and total peripheral resistance. These determinations can be used by the clinician to choose appropriate antihypertensive therapy without resorting to the usual trial-and-error approach. With the aid of hemodynamic measurements, the treatment of hypertension can evolve from merely lowering blood pressure to correcting the whole hemodynamic derangement. In this study, the accuracies and normal ranges of the measurements were critically examined. Results of a comparative trial showed that use of hemodynamic measurements decreased the incidence of side effects and improved compliance of patients to the prescribed antihypertensive regimen.

Adult↗

[Typological characteristics of hemodynamic states in the orthostatism of healthy persons].

Central circulation and respiratory function of 90 healthy men, aged 24-45, were investigated during active and passive tilt tests. It was found that circulation can be influenced by the orthostatic factor which is expressed as the stage of early effects, intermediate stage, and the stage of stabilized hemodynamics. With respect to cardiac output the three basic hemodynamic states can be distinguished: hypokinetic, intermediate, and hyperkinetic. It is shown that circulation parameters in clino- and orthostatics are reciprocally related. It is demonstrated that the cardiorespiratory parameters used can be selectively employed in the classification of the circulating state in orthostatics. It is claimed that the hemodynamic conditions reflect the sequential phase states in circulation regulation. The concept of clino- and orthostatic normative characteristics of hemodynamics is presented.

Adult↗

[Characteristics of the action of strophanthin on central hemodynamics, pulmonary and intrahepatic blood circulation and myocardial contraction].

The effects of strophanthin treatment given in courses on the central hemodynamics, pulmonary, intrahepatic circulation and myocardial contractility were studied in 97 patients with decompensated chronic cor pulmonale depending on the hemodynamic type of circulation. In patients with CNPD and circulatory failure having the hypokinetic circulation, the treatment with strophanthin brought about improvement of the pulmonary and hepatic hemodynamics, increase in myocardial contractility, reduction of congestion. This may be accounted for by an elevation of the MOS, removal of the peripheral spasm on the part of the vascular system, elimination of prolonged venous congestion in the lungs and liver, and improvement of arterial blood flow in these organs. It was shown that in patients with hyperkinetic circulation, administration of strophanthin has an untoward effect on the hemodynamics in the lungs, liver and heart, thereby maintaining and increasing myocardial hyperfunction and venous hypervolemia. The data obtained indicate that it is inadvisable to prescribe strophanthin at early stages of the decompensated chronic cor pulmonale in patients with hyperkinetic circulation.

Adult↗

[Central hemodynamics in chronic alcoholics].

Central hemodynamics were assessed in 86 chronic alcoholic patients in relation to the stage of the disease and the kind of alcoholic dependence. The values of major hemodynamic parameters were shown to depend on both the stage of the disease, and clinical manifestations of abstinence. The abstinence syndrome developing after a 3-5-day abstinence is associated with a gradual transition from eukinetic- to hypokinetic-type circulation, as the disease progresses. Hemodynamic shifts following recovery from acute delirium tremens are not related to the stage of the disease, and tend to hypokinetic-type circulation. During remission, hemodynamic parameters approach those of normal subjects.

Adult↗

Acute hemodynamic effects of hydralazine in dogs with chronic mitral regurgitation.

The hemodynamic response to hydralazine administration was evaluated in 6 conscious small dogs with chronic mitral regurgitation. All dogs underwent invasive and noninvasive hemodynamic monitoring before and after hydralazine administration. Cardiac output and pulmonary capillary wedge pressure were measured with a Swan-Ganz thermodilution catheter. Systemic arterial blood pressure (AP) was measured directly by inserting a needle into the femoral artery. Standard M-mode echocardiograms and thoracic radiographs were obtained. Other hemodynamic variables were calculated. Base-line hemodynamic variables were altered severely in all dogs. Hydralazine decreased mean arterial blood pressure from 104 +/- 18 (mean +/- SD) to 78 +/- 12 mm of Hg (P less than 0.005), total systemic resistance index from 2,946 +/- 625 to 1,261 +/- 420 dynes-s-cm-5m2 (P less than 0.005), and pulmonary capillary wedge pressure from 40 +/- 5 to 26 +/- 3 mm of Hg, (P less than 0.005). Cardiac index increased from 2.92 +/- 0.72 to 5.36 +/- 1.67 L/min/m2 of body surface area (P less than 0.005). Mixed venous oxygen tension (PvO2) increased from 28.4 +/- 4.3 to 41.2 +/- 5.2 mm of Hg (P less than 0.001). Pulmonary edema resolved, as determined on thoracic radiographs. Mixed venous oxygen tension correlated well with the cardiac index (r = 0.92; P less than 0.001). It was concluded that hydralazine administration caused a small decrease in end diastolic diameter (4.8 +/- 0.9 to 4.5 +/- 0.8 cm, P less than 0.05) and end systolic diameter (2.6 +/- 0.8 to 2.3 +/- 0.7 cm, P less than 0.05). Fractional shortening and heart rate did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Hemodynamic changes in immobilization stress].

In chronic experiments on 75 Wistar, August and randombred rats hemodynamic changes were examined during 30-hour immobilization stress. The ECG was recorded and arterial blood pressure measured. The basic hemodynamic characteristics were determined with the help of the previously implanted ultrasonic blood flow probes. Analysis of hemodynamic changes in animals resistant, adapted and prone to stress demonstrated that changes in the total peripheral resistance play the leading role in the disturbance of the arterial blood pressure control. It was established that a progressive lowering of arterial blood pressure resulting from the abruptly reduced total peripheral resistance is the main and the most frequent cause of death of animals exposed to immobilization stress. At the same time the cardiac hemodynamic component may play an essential role in the mechanism of death. This component may include either progressive bradycardia or a combination of an ischemic myocardial damage and reduced total peripheral resistance.

Adaptation, Physiological↗

Effect of systemic autonomic inhibition on the hemodynamic response to antihypertensive therapy with timolol.

To evaluate the role of systemic autonomic tone in the hemodynamic response to beta-inhibitors, the hemodynamic effects of long-term timolol therapy were studied in hypertensive patients under two sets of conditions: at rest and after pharmacologic systemic autonomic inhibition (SAI). Hemodynamic studies were performed in every subject at the end of a 4-week placebo period and again at the end of a 9-week treatment period. The antihypertensive effect of timolol was associated with decreased cardiac output and unchanged peripheral resistance at rest and with unchanged cardiac output and decreased peripheral resistance after SAI. The hemodynamic response to SAI during the two studies was also markedly different. The findings provide evidence of increased alpha-adrenergic component of systemic autonomic tone during long-term therapy with timolol.

Adult↗

[Hemodynamic changes in hypoglycemic shock].

Severe hypoglycemia may be present in seriously ill patients; if it is not corrected opportunely a series of neuroendocrinal mechanisms take place aimed at correcting metabolic alterations. These mechanisms can produce hemodynamic alterations as well. Nine mongrel dogs were studied with continuous registration of: blood pressure, central venous pressure, cardiac frequency, respiratory frequency, electrocardiogram and first derivative (Dp/Dt). Six dogs received crystalline (fast acting) insuline intravenously (group 1). After hemodynamic changes were registered hypoglycemia was corrected with 50 per cent glucose solution. Complementary insuline doses were administered to three dogs (group 2); in this group hypoglycemia was not corrected. In group 1 during hypoglycemia there was an increase in blood pressure, central venous pressure, cardiac frequency, respiratory frequency and Dp/Dt, and changes in QT and T wave on the EKG; these changes were partially reversible after hypoglycemia was corrected. The above mentioned alterations persisted in group 2, breathing became irregular irregular and respiratory arrest supervened. It can be inferred that the hemodynamic response to hypoglycemia is predominantly adrenergic. The role of catecolamines, glucocorticoides, glucagon, insuline, cyclic AMP in metabolic and hemodynamic alterations consecutive to hypoglycemia are discussed.

Animals↗

Hypothalamic neurons responding to hemodynamic input and to stimulation in the pons may influence adrenocorticotropin release.

Experiments were designed to identify hemodynamically sensitive neurons in the mediodorsal hypothalamus and to determine if they were also sensitive to electrical stimulation of areas in the dorsal rostral pons that were implicated previously in the control of adrenocorticotropin (ACTH) release. Cats were anesthetized with chloralose and urethane, immobilized with gallamine, and artificially respired. Hemodynamic stimuli included constriction (CC) of the supradiaphragmatic inferior vena cava to reduce venous return and sinusoidal volume pulsation (RA) of the right atrium (1 ml peak at 1 Hz). Previously, CC was shown to facilitate and RA was shown to inhibit ACTH release. Electrical stimulation in the pons consisted of single shocks (500 microA DC, 0.05 msec, negative-to-tip) delivered on each of an array of three or four bipolar co-axial electrodes in the pons. Twenty-three neurons were tested with only RA. Of these, two were inhibited, two were facilitated, and 19 did not respond. Thirty-two neurons were tested with CC. Of these, nine were inhibited, nine were facilitated, and 14 did not respond. Seventeen neurons that responded either to RA or to CC were tested with stimulation in the pons. Of these, three were orthodromically activated and two were inhibited from a total of eight pontine sites. Six of the eight sites were within 300 microns of an area shown previously to contain neurons that responded to CC. Of 31 additional sites that were stimulated, but at which stimulation did not drive neurons that responded to hemodynamic stimuli, 26 were located more than 300 microns from this area (p less than 0.01, X2 test). The data suggest that some hypothalamic neurons involved in the hemodynamic control of ACTH release receive a projection from or through the dorsal raphe nucleus medially, and the ventral locus ceruleus, locus subceruleus, and underlying reticular formation laterally. However, other neurons may receive projections that bypass these regions.

Adrenocorticotropic Hormone↗

[State of the hemodynamics in pregnant women suffering from mitral stenosis].

Hemodynamics was studied in different trimesters of pregnancy in 94 women with mitral stenosis and in 32 healthy women with pregnancy following a normal course. Each trimester in women with mitral stenosis was marked by different changes in hemodynamics. Study of the state of hemodynamics allows preclinical signs of cardiac insufficiency to be already detected in the early periods. This makes it possible to assess the risk of pregnancy and delivery in women with mitral stenosis at the right time and more correctly. The disclosure of unfavourable signs of changes in hemodynamics in conjunction with the clinical signs of cardiac insufficiency aids in the choice of the therapeutic and obstetrical tactics.

Adolescent↗

[Central hemodynamic status of alcoholism patients].

Central hemodynamic status was assessed in 110 alcoholic patients at rest and after rationed submaximal bicycle ergometric exercise. A direct relationship was established between central hemodynamic parameters and the stage of alcoholism as well as the duration of alcohol abuse. Hemodynamic changes in response to rationed exercise are the most demonstrative. They can be regarded as pathological cardiovascular adaptation of alcoholics to physical stress. Central hemodynamic changes are more dependent on the duration of alcohol abuse than on the stage of alcoholism.

Adult↗