الفهرس | Only 14 pages are availabe for public view |
Abstract Heart failure is the pathophysiologic state in which the heart, via an abnormality of cardiac function (detectable or not), fails to pump blood at a rate commensurate with the requirements of the metabolizing tissues or is able to do so only with an elevated diastolic filling pressure. Heart failure may be caused by myocardial failure but may also occur in the presence of near-normal cardiac function under conditions of high demand. Heart failure always causes circulatory failure, but the converse is not necessarily the case, because various noncardiac conditions (e.g. hypovolemic shock, septic shock) can produce circulatory failure in the presence of normal, modestly impaired, or even supranormal cardiac function. To maintain the pumping function of the heart, compensatory mechanisms increase blood volume, cardiac filling pressure, heart rate, and cardiac muscle mass. However, despite those mechanisms, there is progressive decline in the ability of the heart to contract and relax, resulting in worsening heart failure Studies in patients with heart failure (HF) and left ventricular systolic dysfunction have noted high rates of thromboembolic events as compared to the general population. Thrombus in the left heart chambers (associated with left heart failure) can lead to embolic stroke or peripheral arterial emboli, while pulmonary emboli originate from either deep venous thrombus or thrombus in the right heart chambers (associated with right heart failure). Low cardiac output, decreased physical activity, and peripheral edema all predispose to venous thrombi. In spite of the large number of studies and research conducted in this area, there is still considerable disagreement about the usefulness and importance of the use of anticoagulation therapy as one of the main lines in treatment of heart failure, or to reduce the incidence of death or injury strokes or to reduce the rate of hospitalization, compared to the bleeding risks that may accompany the use of anticoagulants (especially intracerebral hemorrhage).Recent guidelines recommend anticoagulation treatment in patients with chronic Heart failure with reduced ejection fraction with AF, a prior thromboembolic event, a cardioembolic source (LV thrombus), and antiplatelet therapy in established coronary artery disease. |