الفهرس 
Pathophysiology of Heart FailureOnly 14 pages are availabe for public view
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Abstract
Heart failure (HF) often occurs as the terminal common pathway of any combination of cardiac conditions that affect the myocardium’s productivity. It can be described as the inability of the heart to adequately fill or contract in order to meet the body’s metabolic demands
HF is a clinical syndrome characterized by typical symptoms (e.g. breathlessness, ankle swelling and fatigue) that may be accompanied by signs (e.g. elevated jugular venous pressure, pulmonary crackles and peripheral oedema) caused by a structural and/or functional cardiac abnormality, resulting in a reduced cardiac output and/ or elevated intracardiac pressures at rest or during stress.
Worldwide a constant decline of heart transplantations (HTx) is observed. While the numbers of patients awaiting HTx doubled within the last 15 years, available donor organs dropped by a third. In 2015, 790 patients in Germany were listed for HTx with only 286 hearts to be transplanted. A decline in one-year survival after HTx from 85% to 76% in the EuroTransplant region is observed, presumably because of increasing donor age and recipient comorbidity. About 15% of patients listed for transplantation die before an organ is available and more than 30% of patients awaiting HTx need mechanical circulatory support with left ventricular assist devices (LVAD) as bridge to transplant (BTT), therefore, the need for permanent mechanical circulatory support assist devices has increased. In the last decade LVAD systems underwent substantial progress in size, durability, reliability and noise emission. LVAD implantation became a new treatment option for end stage heart failure as destination therapy (DT) for patients either too old or not suitable for transplantation due to other medical conditions. As a result, an exponential increase of LVAD implantations took place within the last five years.Successful long term results after implantations of LVADs are highly dependent on the timing of implantation. LVAD implantation is indicated in patients with end stage heart failure. The criteria for LVAD implantation are NYHA class 4 heart failure refractory to optimal medical therapy, LVEF less than 25%, systolic blood pressure <80 mmHg, pulmonary capillary wedge pressure >20 mmHg, cardiac index <2.0 L/min/m2 despite continuous intravenous inotropic therapy and intra-aortic counterpulsation. In addition, malignant cardiac arrhythmias as well as any patient on transplant waiting list can be considered for LVAD-therapy.With the increasing usage of LVADs and longer survival, a substantial number of patients experience adverse events and complications. LVAD-related complications can occur in up to 60% of patients by six months post-implantation, and, by two years, 80% of patients experience at least one adverse event.
Major, non-surgical, adverse events and complications with the LVAD include bleeding complications, device thrombosis, ischemic and hemorrhagic strokes, renal impairment, multi-organ failure, infections, aortic insufficiency and right ventricular failure which have been the primary causes of death in some series. With regard to timing, complications after LVAD placement can be early (less than 30 days after placement], or late (occurring more than 30 days after placement).