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Metody oceny rezerwy wieńcowej

Gawryś K., Gawryś J., Majchrzak K.

Inżynier i Fizyk Medyczny

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2016

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Vol. 5, nr 6

335--341

PL

Rezerwa wieńcowa, będąca różnicą pomiędzy spoczynkowym a maksymalnym przepływem wieńcowym, a także cząstkowa rezerwa przepływu są przydatnymi parametrami w ocenie pacjentów z chorobą wieńcową i ich kwalifikacji do leczenia zachowawczego bądź rewaskularyzacyjnego. Pośrednie metody oceny rezerwy wieńcowej – próby ergometryczne pozwalają m.in. na ocenę zdolności krążenia wieńcowego do dostarczania odpowiedniej ilości tlenu w sytuacji zwiększonego zapotrzebowania. Do oceny perfuzji mięśnia sercowego i rezerwy wieńcowej wykorzystuje się także skalę TIMI (Thrombolysis in Myocardial Infarction) i jej modyfikacje przydatne w prognozowaniu rokowania u chorych z ostrym zawałem serca oraz w ocenie efektów leczenia reperfuzyjnego, rezonans magnetyczny pozwalający dodatkowo na zbadanie innych parametrów funkcjonalnych serca, SPECT (Single-photon Emission Computed Tomography), PET (Positron Emission Tomography), a także nowoczesne skanery PET-CT i SPECT-CT.

EN

Coronary reserve, defined as the difference between resting and maximum coronary flow, as well as the fractional flow reserve are useful parameters in the evaluation of patients with coronary artery disease and their qualifications to conservative or invasive treatment. Indirect methods of coronary reserve assessment – ergometric tests, allow to assess the capacity to deliver enough amount of oxygen in the case of increased demand. To assess myocardial perfusion and coronary reserve are also used: TIMI (Thrombolysis in Myocardial Infarction) scale – useful in predicting prognosis in patients with acute myocardial infarction and in evaluating the effects of reperfusion therapy, magnetic resonance imaging which allows also to explore other functional parameters of the heart, SPECT (Single-Photon Emission Computed Tomography), PET (Positron Emission Tomography) and modern scanners – PET-CT and SPECT-CT.

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Circulatory assistance: basic classification of heart assistance methods and devices

Górczyńska K.

Biocybernetics and Biomedical Engineering

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2011

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Vol. 31, no. 1

3-15

EN

This paper is focused on basic classification of mechanical circulatory assistance methods and devices regarding a way of their connection to the circulatory system (parallel, "in-series"), different manner of work (pulsatile, continuous-flow) or a goal of appliance (bridge to recovery, bridge to transplant, Total Artificial Heart). Also schematic layout of subjectively chosen assist devices are shown and discussed. The paper does not pretend to give an exhaustive description of mechanical circulatory assistance but rather evidence, after some brief historical remarks, the substance of the circulatory support itself.

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Zastosowanie analizy tekstury obrazu do oceny dynamiki prawidłowego przepływu wieńcowego w badaniu koronarograficznym

Syrycki M., Mazurek W.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2008

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Vol. 14, nr 3

242-244

PL

W pracy przedstawiono wstępne rezultaty przeprowadzonej próby oszacowania prawidłowego przepływu wieńcowego w oparciu o cyfrową analizę sekwencji standardowych obrazów koronarograficznych naczyń wieńcowych o różnej średnicy. Zastosowano rozszerzony pakiet analizy tekstury w postaci programu MaZdaŽ. Dokonano wyboru najważniejszych parametrów tekstury przydatnych do realizacji założonego zadania. Uzyskano wyniki wskazujące na dużą czułość opracowywanej metody.

EN

The paper presents preliminary results of the normal coronary blood flow estimation by means of texture analysis of the standard coronarography scans. The coronary vessels with the various size were examined. The software MaZdaŽ for texture analysis was used. The most significant parameters of the texture, useful for coronary blood flow estimation, were determined and analyzed. The results of performed analysis indicate the high sensitivity of this method.

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Clinical study on the coronary flow measurements method based on coronarographic image sequences

Goszczyńska H., Kowalczyk L., Rewicki M.

Biocybernetics and Biomedical Engineering

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2006

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Vol. 26, no. 2

63-73

EN

Many studies concerning evaluation of the artery blood flow based on coronarographic images have been made. Application of the indicator-dilution technique allows calculation of absolute values of the blood flow in the coronary arteries based on the densitometric analysis of coronarographic image sequences under some specific conditions imposed on injections of the contrast medium and digital image sequences registration. This method is based on densitometric measurements carried out in two sequences of images of the same artery. The first sequence is recorded during the routine injection of the contrast, and the other is recorded during the slow test injection of the contrast with a reduced amount of the indicator. The method was tested on coronarographic images obtained in routine examinations in two groups of control patients. The comparative analysis of 18 patients indicates that there exists a moderate consistency between the results of this method and the clinical assessment. The results of our studies are strongly dependent on the accuracy of the measurements and the method of recording. Proposed method, tested on the model of artery and measurements obtained from coronarographic examinations of control groups of patients, provides grounds for future studies.

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The influence of ventilatory support on coronary flow and oxygen consumption in different circulatory conditions

De Lazzari C., Darowski M., Ferrari G., Mimmo R., Guaragno M., Tosti G.

Biocybernetics and Biomedical Engineering

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2003

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Vol. 23, no. 1

103-110

EN

The aim of this work is to predict the influence of mechanical ventilation on cardiac output, coronary flow and left ventricular myocardial oxygen consumption in different circulatory conditions. To study this interaction we used a computer simulator of human cardiovascular system in which lumped parameters models were used to reproduce the circulatory phenomena in terms of pressure and volume relationships. Variable elastance models reproduce the Starling's law of the heart, for each ventricle. In the study the left ventricular elastance assumed two different values. Symetric arterial resistance was changed during the simulation. The influenece of mechanical ventilation was introduced by positive mean thoracic pressure. Positive thoracic pressure, changes of peripheral resistance and different ventricular elastance values have a significant influence on cardiac output, coronary flow and myocardial oxygen consumption.