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Orvosi Hetilap
Authors: Dávid Zakariás, Gábor Marics, Kata Kovács, Ágnes Jermendy, Barbara Vatai, György Schuster, Péter Tóth-Heyn, Attila Szabó J., and Csaba Lódi

: 447–451. 2 Critchley LA, Critchley JA. A meta-analysis of studies using bias and precision statistics to compare cardiac output measurement techniques. J Clin Monit Comput

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Our previous studies have indicated that nitric oxide takes part in the basal regulation of vascular tone in skeletal muscle. The purpose of this study was to investigate whether nitric oxide has a role in the active hyperaemic response of a working muscle in a resting subject. Haemodynamic effects of nitric oxide synthase (NOS) inhibition (L-NAME, 10 mg/kg/30 min iv. infusion) were determined simultaneously in the resting m. quadriceps femoris and in the working (breathing) m. rectus abdominis in anaesthetised rats ( 86Rb accumulation technique). L-NAME increased blood pressure and total peripheral resistance (TPR) while it decreased cardiac output. Blood flow (BF) decreased and vascular resistance (VR) increased both in resting (BF: 8.91±1.97®5.92±2.59 ml/min/100 g, p<0.05; VR: 106±29.9®212±113 R, p<0.01) and working (BF: 17.0±4.78®6.93±2.15 ml/min/100g, p<0.001; VR: 57.0±18.5®160±56.7 R, p<0.01) muscle following NOS inhibition, but the percentile change of BF was higher in the working muscle (59%) than in the resting one (34%, p0.001). There was a positive correlation between the cardiac output and the blood flow of the resting muscle with or without L-NAME administration, but blood flow of the working muscle failed to have any correlation with the cardiac output in control animals. However, L-NAME administration decreased both the cardiac output and the blood flow and similarly to the resting muscle a positive correlation was found. In conclusion, the haemodynamic effects of NOS inhibition are higher in working muscle than in the resting one: the nitric oxide may have important role in vasodilatation during muscle activity. _a

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Baker LE, Judy WV, Geddes LA, Langley FM, Hill DW: The measurement of cardiac output by means of electrical impedance. Cardiovasc. Research Center Bulletin 9(4), 135-145 (1971) The

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Acta Veterinaria Hungarica
Authors: Róbert Romvári, András Szabó, Gabriella Andrássy, Zsolt Petrási, Tamás Donkó, and Péter Horn

An, P., Rice, T., Gagnon, J., Leon, A. S., Skinner, J. S., Bouchard, C., Rao, D. C. and Wilmore, J. H. (2000): Familial aggregation of stroke volume and cardiac output during sub maximal exercises: the HERITAGE

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Interventional Medicine and Applied Science
Authors: István Hartyánszky, A. Tóth, G. Veres, B. Berta, E. Zima, Z. Szabolcs, G. Y. Acsády, B. Merkely, and F. Horkay

Abstract

Background: Although circular ventricle resection techniques are the gold standard of left ventricle restoration, these techniques can lead to suboptimal results. Postoperative systolic resection line can be inadequate, as it must be planned on a heart stopped in diastole. The impaired geometry and contractility may lead to increased short- and long-term mortality. Moreover, postoperative low cardiac output due to insufficient left ventricular volume results in a potentially unstable condition, and cannot be corrected. Our aim was to find a preoperative method to minimize risk and maximize outcome with left ventricle restoration. Methods: We have created a novel method combining surgery with modern imaging techniques to construct a preoperative 3D systolic heart model. The model was utilized to determine resection could be intraoperatively used to create the new left ventricle. Results: The computer assisted ventricle engineering technique is described step by step through a successful aneurysmectomy of a 61-year-old female patient with a complicated giant left ventricle aneurysm. Conclusions: Using this model we are able to find the optimal resection line providing excellent postoperative result, thus minimizing the risk of low cardiac output syndrome. This is the first report of our new combined approach to left ventricle restoration.

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Acta Physiologica Hungarica
Authors: T. Yano, R. Afroundeh, R. Yamanak, T. Arimitsu, C. Lian, K. Shirkawa, and T. Yunoki

The purpose of the present study was to examine how end tidal CO2 pressure (PETCO2) is controlled in impulse exercise. After pre-exercise at 25 watts for 5 min, impulse exercise for 10 sec with 200 watts followed by post exercise at 25 watts was performed. Ventilation (V̇E) significantly increased until the end of impulse exercise and significantly re-increased after a sudden decrease. Heart rate (HR) significantly increased until the end of impulse exercise and then decreased to the pre-exercise level. PETCO2 remained constant during impulse exercise. PETCO2 significantly increased momentarily after impulse exercise and then significantly decreased to the pre-exercise level. PETCO2 showed oscillation. The average peak frequency of power spectral density in PETCO2 appeared at 0.0078 Hz. Cross correlations were obtained after impulse exercise. The peak cross correlations between V̇E and PETCO2, HR and PETCO2, and V̇E and HR were 0.834 with a time delay of −7 sec, 0.813 with a time delay of 7 sec and 0.701 with a time delay of −15 sec, respectively. We demonstrated that PETCO2 homeodynamics was interactively maintained by PETCO2 itself, CO2 transportation (product of cardiac output and mixed venous CO2 content) into the lungs by heart pumping and CO2 elimination by ventilation, and it oscillates as a result of their interactions.

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As consequence of the expansion of sedentary lifestyle among schoolchildren the prevalence of particular symptoms related to decreased cardiorespiratory fitness increases. The purpose of this study was twofolds, on one hand to compare boys in three developmental groups: second childhood (G1), puberty (G2), young adult (G3) and on the other hand to compare groups classified on resting systolic blood pressure (RSBP) to differentiate cardiorespiratory output determining factors both at rest and at maximal load. Randomly selected apparently healthy boys were assessed, all subjects (n = 282) performed an incremental treadmill test until fatigue. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP), and oxygen consumption were measured. Resting HR was higher and resting SBP and DBP were lower in the G1 as compared to G2 and G3 (p < 0.05) but not differed at maximal loads. However indicators of cardiovascular load differed between groups. The oxygen pulse and Q were the lowest in the G1 and increased significantly between groups (p < 0.05). In conclusion based on our data we can suggest that there is an observable development of hypertension associated with maturation and cardiac output determining factors.

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A dynamic magnetic resonance imaging (MRI) method was developed for in vivo examination of the pig heart. Measurements were carried out on 15 meat-type pigs of different liveweight using a 1.5 T equipment. Inhalation anaesthesia was applied, then data acquisition was synchronised by ECG gating. Depending on the heart rate and heart size, in each case 8 to 10 slices and in each slice 8 to 14 phases were acquired prospectively according to one heart cycle. During the post-processing of the images the left and the right ventricular volumes were determined. The values measured at 106 kg liveweight are 2.5 times higher than those obtained at 22 kg, while the ejection fractions are equal. The calculated cardiac output values were 3.5 l (22 kg, 132 beats/min.), and 6.0 l (106 kg, 91 beats/min.), respectively. After measuring the wall thickness, the contraction values were also determined for the septum (70%), and for the anterior (61%), posterior (41%) and lateral (54%) walls of the left ventricle. Three-dimensional animated models of the ventricles were constructed. Based on the investigations performed, the preconditioning, the anaesthetic procedure, the specific details of ECG measurement and the correct MR imaging technique were worked out.

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Magyar Sebészet
Authors: Miklós Nógrády, Gabriella Varga, Szilárd Szűcs, József Kaszaki, Mihály Boros, and Dániel Érces

Absztrakt:

Bevezetés: A nem okkluzív mesenterialis ischaemia (NOMI) anatómiai okok nélkül alakul ki, korai diagnosztizálása nehéz, terápiája sem megoldott. Modellkísérleteinkben a komplement C5a gátlásán keresztül a komplementaktiváció szerepét vizsgáltuk a kórfolyamatban. Anyagok és módszerek: A NOMI rövid és hosszú távú hemodinamikai és gyulladásos következményeinek jellemzéséhez Sprague–Dawley patkányokban (n = 28) 60 perces parciális aortaokklúziót (PAO; hasi aorta, truncus coeliacustól proximálisan; arteria femoralis középnyomása: 30–40 Hgmm), míg vietnami törpesertésekben (n = 19) 60 perces pericardialis tamponádot (artériás középnyomás: 40–50 Hgmm) hoztunk létre. A PAO, valamint a tamponád 45. percében komplement C5a-gátló kezelést alkalmaztunk (acetil-peptid-A; 4 mg/kg iv.). Az állatokban monitoroztuk a makro- és mikrokeringést, mértük a leukocytainfiltrációt, a gyulladásos mediátorok (endothelin, HMGB-1) plazmaszintjét. Eredmények: Patkányokban a PAO megszüntetése után 24 órával a C5a gátlása csökkentette a szisztémás gyulladásos válasz részeként megemelkedett perctérfogatot (203,1 ± 5 vs. 269,6 ± 8,1 ml/‌min/‌kg) és arteria mesenterica superior (AMS) áramlását, fokozta az ileum mucosa mikrokeringését (833,5 ± 33,8 vs. 441,9 ± 22,4 μm/s). Az acetil-peptid-A sertésekben átmenetileg növelte az AMS áramlását és tartósan az ileummucosa-kapillárisáramlást (648,1 ± 45,4 vs. 329,8 ± 12,6 μm/s). A kezelt állatoknál alacsonyabb gyulladásos mediátorszintet és szöveti leukocytainfiltrációt mértünk mindkét NOMI-modellben. Következtetések: A komplementaktiváció jelentős szerepet játszik a NOMI alatt bekövetkező makro- és mikrokeringési zavar kialakulásában, a C5a gátlása a gyulladásos folyamat mérséklése mellett befolyásolja a NOMI hemodinamikai következményeit is.

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Magyar Sebészet
Authors: Gábor Bari, Szilárd Szűcs, Dániel Érces, Melinda Ugocsai, Noémi Bozsó, Dóra Balog, Mihály Boros, and Gabriella Varga

Absztrakt:

Bevezetés: A pericardialis tamponád az életet közvetlenül veszélyeztető, alacsony perctérfogatú kórállapot, amelynek keringési következményei minden szövet, köztük a vese és a bélnyálkahártya mikrokeringését is súlyosan érintik. Célkitűzés: Kísérletünk célja a pericardialis tamponád klinikai képének modellezésére alkalmas, hemodinamikailag stabil, kontrollálható állatmodell kifejlesztése volt. Módszerek: Altatott vietnami törpesertések két csoportjában laparotomiát követően a szívburokba a rekeszen keresztül, thoracotomia nélkül kanült helyeztünk. Az első, álműtött csoport kontrollként szolgált (n = 6), a második csoportban a pericardium saját vérrel való feltöltésével 60 perces tamponádot hoztunk létre (n = 6). Monitoroztuk a tamponád és az azt követő 180 perces reperfúzió alatt a makrohemodinamikát és a vékonybél mikrohemodinamikai változásait. Vizsgáltuk a fehérvérsejt-akkumulációt jelző mieloperoxidáz (MPO) -enzimaktivitást és pásztázó lézeres endomikroszkóppal a vékonybél in vivo szövettani elváltozásait. Eredmények: A tamponád következtében megemelkedett a centrális vénás nyomás és a szívfrekvencia, lecsökkent az artériás középnyomás, az arteria mesenterica superior (355,5 ± 112,4 vs. 182,0 ± 59,1 ml/min) és az arteria renalis (159,63 ± 50,7 vs. 35,902 ± 27,9 ml/min) áramlása, valamint az ileum mikrokeringése. Az MPO-aktivitás szignifikánsan megemelkedett (3,66 ± 1,6 vs. 7,01 ± 1,44 mU/mg fehérje) és romlott a vékonybél in vivo szövettani képe. Következtetések: Kísérleti modellünk alkalmas a szívtamponád jellegzetes keringési és biokémiai következményeinek vizsgálatára, reprodukálható, klinikailag releváns állatmodellnek tekinthető.

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