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W Urbaszek

Publications and source records attributed to W Urbaszek.

At least 55 records · Page 3Linked to original sources
PubMed1982

[Experiences with the Rostock artificial heart].

A totally artificial heart--the Rostock totally artificial heart (Rostock TAH) was implanted in calves. We can give the following deductions after 27 examinations: -- The Rostock TAH was tested successfully in endurance test about 7 months; it show no sign of wear. -- The surgical technique of the implantation was standardised and a successful experimentation is possible. -- The longest survival time was 15 days. The hemodynamic early results were very good in 3 other animals. -- Modifications of the Rostock TAH were taken up relating to the dimensions of the artificial ventriculi and by mounting a screw cap for avoiding an air embolism. -- Adaption tests in the corpse show that the present form of the artificial heart is not ideal for a possible application in man. -- The problem is still existing in developing a suitable drive system locates intrathoracically. The present drive and control system on a pneumatic base is qualified only for the animal experiment but not for a possible application in man.

Anesthesia, General↗
PubMed1981

[The artificial heart - wishful thinking or alternative?].

The development of the highly specialised cardiological diagnostics furthered the morphological and functional analysis of the congenital and acquired heart diseases. Parallel to this the therapeutic repertoire of the cardiosurgery increased. Successful animal-experimental investigations with artificial hearts and survival times up to several months allow as a justified aim the imagination that the artificial heart by all means may be an alternative to the heart transplantation also in man. This high aim demands further intensive work concerning the optimum form of artificial hearts, better qualities of the material, miniaturised units of motion and regulation with a possibly implantable or at least easily portable source of energy.

Animals↗
PubMed1980

[The use of sodium nitroprusside (Nipruton) in ischemia-related acute heart insufficiency].

By controlled vasodilation with nitroprusside sodium we succeed in improving the negative haemodynamic effects of the pumping insufficiency in myocardial ischamia. Increased filling pressures decrease, volumes of output increase in clearly decreased oxygen consumption of the myocardium. The influence on the time volume of the heart depends on the height and reaction of the filling pressure on nitroprusside sodium. In normal LVEDP the time volume of the heart decreases by nitroprusside sodium. The local function of the heart may clearly be improved under nitroprusside sodium in ischaemia. Altogether the hitherto got results in man are not homogeneously interpreted. Problems result from in form of therapy necessary frequent controls of the filling pressures and volumes of output as well as from the possible decrease of the time volume of the heart and the critical reduction of the perfusion pressure. According to own results of experiments on animals the sequelae of ischaemia may be reduced under the infusion of nitroprusside sodium. The restricted regional function of the heart is particularly improved. An obligatory judgment concerning the temporarily restricted use of nitroprusside sodium in the pumping insufficiency conditioned by ischaemia is not yet possible. A complicating effect have the individually different dose-effect-relations as well as not foreseeable haemodynamic results as a sequel of the basic disease in the complicated myocardiac infarction which is to be regarded as indication.

Animals↗
PubMed1980

[Therapeutic principles of drug-induced cardiac debit with vasodilators].

For the haemodynamically controlled preload reduction (LVEDP and ZDV) as well as the afterload reduction (arterial blood pressure) with volume of output taken into consideration in the first place glycerol trinitrate, nitroprusside sodium, alpha-blockers, hydralazine, prazosine and nitrates are used. The medication is given in acute and chronic pumping insufficiency. The distance between therapeutic effect wanted and unfavourable influences due to critically reduced preload and coronary perfusion as well as reduced volume of output is close. The haemodynamic analysis of actual situation of the disease as well as regular controls are necessary. The effects of the long-term therapy in chronic pumping insufficiency with peroral effective vasodilators are still unsatisfactory.

Adrenergic alpha-Antagonists↗
PubMed1980

[Evaluation of regional heart function by means of local changes in pressure and direction in the vector cardiogram].

Regional function parameters under myocardial ischemia are frequently clearly changed when the parameters as the stroke volume, cardiac output, ejection fraction and the like are still unchanged by a compensation mechanism. Length changes can be measured regionally and phasically by means of a mercury wire strain gauge. The active shortening during the ejection time in relation to the total length change in this region is a possibility for the registration of the relative systolic shortening (delta LS%). Changes will be quantified still clearer and earlier if in the x-y display a vector representation of the regional displacements with the pressure in the left ventricle takes place. The plane of this vector decreased already a few seconds after the coronary occlusion. This is therefore a special early change in ischemia. The important for the estimation of therapeutic measures and other indirect measuring methods is accentuated.

Animals↗
PubMed1978

[The effect of early appearing extrasystoles on systemic and coronary circulation].

In 10 anaesthesized dwarf pigs with an open thorax the effects of extrasystoles on systemic and coronary circulation were investigated. The actual effect of an extrasystole depends on the time of its onset. Early extrasystoles hamper the cardiac blood perfusion, with decreases in the stroke volume, mean arterial pressure, coronary blood flow, and elevation of coronary resistance. Extrasystoles setting on later are of minor haemodynamic and coronarodynamic importance. The effects of bigeminy and 2:1 extrasystolia are more adverse than the consequences of extrasystoles with later onset. With cumulation of several consecutive extrasystoles also adverse the haemodynamic coronarodynamic sequelae increase, in dependence on the magnitude of the quotient coupling time /extrasystolic excitation period [ greater than 1.1], or of the quotient: duration of pre- and postextrasystolic intervals/ normal interval of heart action [ greater than 1.5]. The authors point out the importance of haemodynamic findings during early extrasystoles in ischaemic heart disease.

Animals↗
PubMed1977

[The effect of cardiovascular hypertrophy on the work capacity of hypertensive patients].

Hypertensive persons with pathological ECG in rest compared with healthy persons and hypertensives with normal ECG in rest show a significantly decreased physical efficiency. In hypertensives in stage II disturbances in form of references to a stress heart insufficiency, to a stress coronary insufficiency and a circulatory dysregulation are the cause of the disturbed function of the circulation. Thus the pathological ECG in rest in the hypertensive is an important diagnostic and prognostic criterion for practice.

Blood Pressure↗
PubMed1977

[Behavior of cardiopulmonary function in hypertonics under ergometer load].

In 56 male hypertensive patients a complex cardiopulmonary functional diagnosis was performed in rest and under ergometer load. The total functional capacity of the hypertensive patients is decreased already in the early stage and also in juvenile age, compared with healthy persons. Furthermore disturbances of the regulations of the minute output of the heart, hypertensive stress reactions, disturbances of the coronary blood supply and disturbed functions of the myocardium are provable.

Adult↗
PubMed1976

[Importance of continuous recording of vascular resistance].

The behaviour of resistance in the periphery of the circulation and in the organic regions underlies different influences. Depending on the function of the organs, on the situation of heart and circulation and on the therapeutic influences the vascular resistance changes. To the study of the dynamics of the behaviour of resistance particularly the continuous electronic recognition is suitable. The gain of time and information is great. Especially for the determination of the coronary perfusion in different functions of heart and circulation the continuous registration of the vascular resistance is necessary. Its importance was as an example demonstrated for the left-ventricular ejection resistance and for the left- and right-coronary influx resistance.

Animals↗
PubMed1976

[Assessment of the coronary circulation regulation by means of the so-called isometric contraction index].

The index of isometric contraction formed from the quotient period of isometric contraction in the erect position by period of isometric contraction in lying position gives the possibility to separate between cardially sufficient and cardially insufficient patients with adequately disturbed regulation of the cardiac circulation. The recognition of early stages of the disturbed left-ventricular function is possible. The use of an adequate exact technique in gaining the primary data is to be presumed. Corrections of the frequency of the index of isometric contraction do not improve the evidence. In the borderline region of the index of isometric contraction with values between 1.03 and 1.1 in questionable cases a further differentiation into still normal or already latent insufficient will do by the analysis of the trend of the index of isometric contraction after the application of medicaments. The determination of the change of the direction of the index of isometric contraction after peroral application of nitroglycerin would be justifiable in routine work after the recognition of the initiaction increases in patients with latent heart insufficiency, in patients with a healthy heart it decreases. The clinical value of the index of isometric contraction as a simple test of the circulatory function is highly to be estimated.

Coronary Circulation↗
PubMed1976

[Hemodynamic aspects in the evaluation of heart function using systolic time intervals].

Not invasively determined systolic time intervals give references to the left-ventricular function. Restrictions result from the fact that the systolic time intervals are differently influenced by haemodynamic factors. The inotropic state, the pre and after load, the stroke volume, the frequency as well as the sympathoadrenal system have an effect on the systolic time intervals. In addition to this come specific changes of the haemodynamics by valvular lesions and by pharmaca effective on heart and circulation. In as far about established systolic time intervals clinically usable data concerning the disturbed left-ventricular pumping function may be received, was reported on. On principle with certain restrictions a usable separation of groups between normal and disturbed cardiac function is possible. The judgment of the individual case is restricted due to considerable disperions of individual values. Also by an improved measuring technique as well as by tolerance tests the evidence could not convincingly be improved. On the other hand, with the help of the index of isometric contraction after Rentsch (preejection period in the erect position divided by preejection period in lying position) a separation into normal and beginning left ventricular dysfunction is possible in a well reproducible way.

Adult↗
PubMed1976

[Vetorial presentation of left-ventricular pressure parameters for the assessment of ventricular function].

The ventricle function can be established by the vectorial description of left-ventricular pressure parameters or flow sizes, respectively. The vector diagrammes result from the momentaneous pressure within the ventricle on the X-axis and the differentiated pressure curve or the aortic flow, respectively, on the Y-axis. Well surveyable from the vector loop received (LVP/dp/dt) are established dp/dtmax, dp/dtmin, LVPmax, LVEDP as well as the tg of the pressure increase speed or the pressure decrease speed, respectively, pro developed pressure. By way of example medicamentous changes of the vector diagrammes were induced and the parameters mentioned established. The vectorial demonstration of the left-ventricular haemodynamics seems to give additional informations concerning the phase of centraction and relaxation

Adrenergic beta-Antagonists↗
PubMed1976

[Electronic processing of intravascular by measured blood pressure].

With the help of electronic processing of measurement values the possible information content of the dynamic blood pressure measured by means of the electromanometer is explained. Commericial writing systems and pressure changers are supplemented by self-constructed and especially dimensioned additional devices. Partly in connection with flow sizes by multiplication, division, addition, subtraction, differentiation and integration from pressure values special references to the behaviour of the haemodynamics of certain parts of the circulation are to be obtained. This is explained by examples. In addition to this the authors deal with the systolic and diastolic indication of blood pressure important for haemodynamic measuring programs, with the electronic mean value formation, with the limitaor connection for the indication of the enddiastolic ventricular pressure as well with the short-term accumulation. The electronic processing of the intravasally measured blood pressure as well as of flow values is necessary for analyses of the circulation.

Blood Pressure↗