The growth in the experimental research of facilities to support extracorporeal circulation requires the further development of models of acute heart failure that can be well controlled and reproduced. Two types of acute heart failure were examined in domestic pigs (Sus scrofa domestica ): a hypoxic model (n=5) with continuous perfusion of the left coronary artery by hypoxic deoxygenated blood and ischemic model (n=9) with proximal closure of the left coronary artery and controlled hypoperfusion behind the closure. The aim was a severe, stable heart pump failure defined by hemodynamic parameters changes: a) decrease in cardiac output by at least 50 %; b) decrease in mixed venous blood saturation to under 60 %; c) left ventricular ejection fraction below 25 %; and d) decrease in flow via the carotid arteries at least 50 %. Acute heart failure developed in the first group in one animal with no acute mortality and in the second group in 8 animals with no acute mortality. In the case of ischemic model the cardiac output fell from 6.70±0.89 l/min to 2.89±0.75 l/min. The saturation of the mixed venous blood decreased from 83±2 % to 58±8 %. The left ventricular ejection fraction decreased from 50±8 % to 19±2 %. The flow via the carotid arteries decreased from 337±78 ml/min to 136±59 ml/min (P≤0.001 for all comparisons). The proposed ischemic model is not burdened with acute mortality in the development of heart failure and is suitable for further use in experimental research into extracorporeal circulatory support., S. Lacko, M. Mlček, P. Hála, M. Popková, D. Janák, M. Hrachovina, J. Kudlička, V. Hrachovina, P. Ošťádal, O. Kittnar., and Obsahuje bibliografii
In some patients, heart failure (HF) is associated with increased pulmonary vascular resistance (PVR). The magnitude and the reversibility of PVR elevation affect the HF management. Sildenafil has been recently recognized as potent PVR-lowering drug in HF. The aim of the study was to compare hemodynamic effects and pulmonary selectivity of sildenafil to prostaglandin E1(PGE1). Right-heart catheterization was performed in 13 euvolemic advanced HF patien ts with elevated PVR (6.3±2 Wood's units). Hemodynamic parameters were measured at the baseline, during i.v. infusion of PGE1 (alprostadil 200 ng·kg-1·min-1 ) and after 40 mg oral do se of sildenafil. Both drugs similarly reduced systemic vascular resistance (SVR), but sildenafil had higher effect on PVR (-28 % vs. -49 %, p=0.05) and transpulmonary pressu re gradient than PGE1. The PVR/SVR ratio - an index of pulmonary se lectivity, did not change after PGE1(p=0.7) but it decreased by -32 % (p=0.004) after sildenafil. Both drugs similarly reduced pulmonary artery mean and wedge pressures and increa sed cardiac index (+27 % and +28 %). Sildenafil led more often to transplant-acceptable PVR while causing smaller drop of mean systemic pressure than PGE1. In conclusion, vasodilatatory effects of sildenafil in patients with heart failure are more pronounced in pulmonary than in systemic circulation., H. Al-Hiti ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Srdeční resynchronizační terapie (CRT) zlepšuje kvalitu života a/nebo hemodynamické parametry jen u dvou třetin pacientů s biventrikulárním kardiostimulátorem naimplantovaným pro srdeční selhání. U ostatních pacientů (nonrespondérů) se provádí další jemnější programace kardiostimulačních parametrů. Tato optimalizace atrioventrikulárního a ventrikulo‑ventrikulárního zpoždění (AVD a VVD) může zlepšit výkon srdce u části z nich. Efekt AVD a VVD programace se nejčastěji hodnotí pomocí echokardiografických veličin (charakter plnění levé komory, délka diastolické fáze, tepový objem/srdeční výdej, ejekční frakce, LV dP/dT, synchronie kontrakce levé komory pomocí tissue Doppler nebo speckle trackingu). Zatímco všechny tyto parametry prokázaly bezprostřední efekt AVD/VVD optimalizace ve vybraných souborech CRT pacientů, dlouhodobý benefit optimalizace se nepodařilo prokázat randomizovanými studiemi ani metaanalýzou. Článek popisuje současný teoretický koncept optimalizace, metodologické problémy a nevyřešené otázky a dostupnou důkazní literaturu. Možnosti optimalizace jsou shrnuty v současných odborných guidelines, doporučuje se však individuální přístup., Cardiac resynchronization therapy (CRT) improves the quality of life and/or haemodynamic parameters only in 2/3 of heart failure patients with a biventricular pacemaker implanted. In the rest of these patients (non‑responders), further refinement of pacing parameters is provided. This atrioventricular delay (AVD) and ventriculoventricular delay (VVD) optimization may help to improve cardiac performance in some of them. Echocardiography is widely used to assess the effect of AVD and VVD programming. The diastolic filling pattern, the length of the diastole, stroke volume/cardiac output, ejection fraction, LV dP/dT and LV contraction synchrony by tissue Doppler or speckle tracking are the most frequent criteria used for optimization. Whilst all these variables are proved to demonstrate an instant effect of AVD/VVD optimization in selected groups of CRT patients, neither a randomized study nor a meta‑analysis showed any long‑term benefit in the CRT population. This article describes the theoretical concept of optimization, certain methodological problems and unresolved issues in CRT optimization and evidence in literature already published. Optimization options are summarized in current guidelines but an individual approach is recommended in non‑responders., and Marek D.
A higher mean arterial pressure (MAP) achieved by norepinephrine up-titration may improve organ blood flow in critically ill, whereas norepinephrine-induced afterload rise might worsen myocardial function. Our aim was to assess the effects of norepinephrine dose titration on global hemodynamics in cardiogenic shock. We prospectively evaluated 12 mechanically ventilated euvolemic patients (aged 67±12 years) in cardiogenic shock (10 patients acute myocardial infarction, 1 patient dilated cardiomyopathy, 1 patient decompensated aortic stenosis). Hemodynamic monitoring included arterial and Swan-Ganz catheters. The first data were obtained at MAP of 65 mm Hg, then the norepinephrine dose was increased over 40 min to achieve MAP of 85 mm Hg. Finally, the norepinephrine-dose was tapered over 40 min to achieve MAP of 65 mm Hg. Norepinephrine up-titration increased MAP to the predefined values in all patients with concomitant mild increase in filling pressures and heart rate. Systemic vascular resistance increased, whereas cardiac output remained unchanged. During norepinephrine down-titration, all hemodynamic parameters returned to baseline values. We observed no changes in lactate levels and mixed venous oxygen saturation. Our data suggest that short-term norepinephrine dose up-titration in cardiogenic shock patients treated or pretreated with inotropes was tolerated well by the diseased heart., R. Rokyta, Jr ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Nemoci ledvin mohou graviditě předcházet nebo se manifestují až v jejím průběhu. V prvním trimestru vzniká akutní poškození ledvin nejčastěji následkem hyperemesis gravidarum, ektopické gravidity nebo potratu. Ve druhém a třetím trimestru jsou nejčastějšími příčinami akutního poškození ledvin těžké formy preeklampsie, HELLP syndrom, akutní těhotenská steatóza a trombotická mikroangiopatie. Stanovení diagnózy u těchto stavů je často problematické. Kortikální nekróza a obstrukční uropatie mohou též vést k akutnímu poškození ledvin. Včasné rozpoznání těchto poruch je nezbytnou podmínkou včasného zahájení léčby a zlepšení prognózy těhotné ženy i plodu. U žen s preexistujícím onemocněním ledvin, zejména chronickou glomerulonefritidou, diabetickou nefropatií a lupusovou nefritidou, závisí výsledky těhotenství i na stupni stupni poškození ledvin, tíži proteinurie a závažnosti hypertenze. U většiny pacientek s mírnou poruchou funkce ledvin a dobrou korekcí hypertenze je prognóza těhotenství i renálních funkcí pacientky dobrá. U nemocných se středně těžkou nebo těžkou poruchou funkce ledvin jsou však výsledky těhotenství horší. V posledních letech naše znalosti v problematice interakce renálních funkcí a gravidity výrazně pokročily, což umožnilo zlepšení výsledků těhotenství u nefrologických pacientek. Přibývají případy úspěšných těhotenství u pacientek v konečném stadiu selhání ledvin, na dialyzační léčbě a po transplantaci ledviny. U těhotných pacientek po transplantaci ledviny je nutné speciální plánování farmakoterapie., Kidney disease and pregnancy may exist in two general settings: acute kidney injury that develops during pregnancy, and chronic kidney disease that predates conception. In the first trimester of pregnancy, acute kidney injury is most often the result of hyperemesis gravidarum, ectopic pregnancy, or miscarriage. In the second and third trimesters, the common causes of acute kidney injury are severe preeclampsia; haemolysis, elevated liver enzymes and low platelets syndrome; acute fatty liver of pregnancy; and thrombotic microangiopathies, which may pose diagnostic challenges to the clinician. Cortical necrosis and obstructive uropathy are other conditions that may lead to acute kidney injury in these trimesters. Early recognition of these disorders is essential to timely treatment and can improve both maternal and foetal outcomes. In women with preexisting kidney disease, mainly including chronic glomerulonephritis diabetic nephropathy and lupus nephritis, pregnancy‑related outcomes depend upon the degree of renal impairment, the amount of proteinuria, and the severity of hypertension. In the majority of patients with mild renal function impairment, and well‑controlled blood pressure, pregnancy is usually successful and does not alter the natural course of maternal renal disease. Conversely, fetal outcome and long‑term maternal renal function might be seriously threatened by pregnancy in women with moderate or severe renal function impairment. During the last few years, advances in our knowledge about the interaction of pregnancy and renal function has resulted in the improvement of foetal outcome in patients with chronic renal failure and also in the management of pregnant women with end‑stage renal disease (ESRD) maintained on dialysis. Neonatal and maternal outcomes in pregnancies among renal transplant patients are generally good if the mother has normal baseline allograft function. Common renally active drugs and immunosuppressant medications must be prescribed, with special considerations in pregnant patients., and Zakiyanov O., Vachek J., Tesař V.