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
Kardiomyopatie představuje heterogenní skupinu onemocnění srdečního svalu, provázenou poruchou srdeční funkce. Tachykardií indukovaná kardiomyopatie (TIC) je způsobena déle trvající tachykardií vedoucí k dilataci a systolické dysfunkci s klinickými projevy srdečního selhání, které jsou reverzibilní po normalizaci tepové frekvence. Diagnóza je obvykle stanovena retrospektivně po normalizaci tepové frekvence a následné úpravě funkce levé komory (LKS). Více než 100 let po prvním dokumentovaném případu (roku 1913 popsána u mladého nemocného s fibrilací síní a projevy srdečního selhání [25]) jsou nadále znalosti patofyziologických mechanizmů omezené. Mezi nejčastější arytmie odpovědné za TIC patří fibrilace síní [1,2], flutter síní [3], incesantní supraventrikulární tachykardie [4], komorová tachykardie (KT) [5] a frekventní komorové extrasystoly (KES) [6]. Vzhledem k potenciální reverzibilitě je proto rozpoznání TIC a včasný terapeutický zásah stěžejní. Mezi stávající možnosti léčby patří farmakoterapie a chirurgická či katetrová ablace., Cardiomyopathy is a heterogeneous group of diseases of heart muscle accompanied with impaired cardiac function. Tachycardia-induced cardiomyopathy (TIC) is caused by prolonged tachycardia leading to dilatation and systolic dysfunction with clinical manifestation of heart failure. This state is reversible after normalization of heart rate. The diagnosis is usually made retrospectively after normalization of heart rate and recovery of left ventricular function (LVF). More than 100 years after the first documented case (described in 1913 in a young patient with atrial fibrillation and symptoms of heart failure [25]) is still limited knowledge of pathophysiological mechanisms. The most common arrhythmias responsible for the TIC include atrial fibrillation [1,2], atrial flutter [3], incessant supraventricular tachycardia [4], ventricular tachycardia (VT) [5] and frequent ventricular extrasystoles (VES) [6]. TIC detection and therapeutic intervention is crucial considering potential reversibility of tachycardia. Current options of treatment involve drug therapy and surgical or catheter ablation., and Jan Povolný
Chronic volume overload (VO) on the left ventricle (LV) augments redox stress and activates matrix metalloproteinase (MMP) which causes the endocardial endothelial-myocyte (EM) disconnection leading to myocardial contractile dysfunction. VO-induced MMP-9 activation impairs cardiac functions, in part by endothelial endocardial apoptosis, but the role of MMP-9 on EM functions remains obscure. We conjecture that chronic VO activates MMP-9 and causes EM uncoupling. Arteriovenous fistula (AVF) was created in genetically identical wild type (WT) mice (FVB/NJ) and MMP-9 knockout mice (MMP-9KO, FVB.Cg-MMP9tm1Tvu/J). Sham-operated mice were used as controls. Before experimentation the phenotype analysis of MMP-9KO mice was carried out. In-gel-gelatin zymography for MMP-9 activation was performed on LV homogenates. The EM functions were determined on LV rings using tissue myobath. We report a decrease in MMP-9 activity in left ventricular myocardial extracts in MMP-9 deficient mice after AVF. The responses to drugs affecting cardiac functions (acetylcholine (Ach), nitroprusside and bradykinin) were attenuated in AVF mice suggesting the impairment of EM coupling. Interestingly, the EM functions were restored in the MMP-9 deficient mice after AVF. We suggest a direct cause-and-effect relationship between MMP-9 activation and EM uncoupling in LV myocardium after chronic VO and the possible involvement of MMP-9 in myocardial contractile performance., K. S. Moshal, W. E. Rodriguez, U. Sen, S. C. Tyagi., and Obsahuje bibliografii a bibliografické odkazy
Chronic heart failure has become a significant health problem. Cardiac surgery has an important role in the treatment of patients with heart failure. There are traditional surgical techniques in cardiac surgery – coronary revascularization, valve surgery, ventricular reconstructive surgery as well as new surgical techniques – cardiac support device (CorCap), mechanical circulatory support and resynchronization therapy. Cardiac surgery has a definitive role in the treatment algorithm for chronic heart failure., J. Pirk., and Obsahuje seznam literatury