Congestive Heart Failure (CHF) CHF results from an inadequate or decreased cardiac output which causes an increase in the blood volume within the vascular system. The resulting congestion within the venous system interferes with the movement of body fluids, resulting in fluid accumulation in the tissue spaces, causing edema . Condition that occurs as a result of impaired pumping capability of the heart and is associated with abnormal retention of water and sodium.
General Cause of CHF #1: Ventricular failure – a condition where the contractions of the ventricles become weak and ineffective, as in myocardial ischemia from coronary artery disease. Edema – An abnormal accumulation of fluid in intercellular spaces of the body. There are three general kinds of pathological conditions that can cause CHF:
Left ventricular heart failure Failure of the left ventricle to maintain a normal output of blood. Since the left ventricle does not empty completely, it cannot accept blood returning from the lungs via the pulmonary veins. The pulmonary veins become engorged and fluid seeps out through the veins and collects in the lungs, which results in pulmonary edema.
Right ventricular heart failure Failure of the right ventricle to maintain a normal output of blood. Since the right ventricle does not empty completely, it cannot fully accept blood returning from the body. Pressure builds in the veins of the body causing fluid to seep out and collect in the cells of the body – especially the extremities. Engorgement of the systemic veins, produces pitting edema , enlargement of the liver, and ascites.
General Cause of CHF #2: Mechanical failure – the ventricles fail to fill with blood during diastole , which can occur when the mitral valve is narrowed (mitral valve stenosis) or when there is an accumulation of fluid within the pericardial sac pressing against the ventricles, preventing them from accepting a full load of blood. Pericardium or Pericardial sac The membranous sac filled with serous fluid that encloses the heart and the roots of the aorta and other large blood vessels.
<ul><li>The pericardial sac surrounds the heart to prevent friction as the heart expands and contracts. </li></ul>Visceral pericardium - the innermost of the two layers of the pericardium fused to the surface of the heart. Parietal pericardium - the tough, outermost layer that is attached to the diaphragm and the sternum.
Pericardiocentesis If excess fluid accumulates in the pericardial sac, the fibrous pericardium limits expansion. It may be necessary to remove that fluid so the heart can expand normally.
General Cause of CHF #3: An overload of blood in the ventricles during the systole phase of the cycle. High blood pressure ( hypertension ), aortic stenosis and aortic valvular regurgitation are some of the conditions that can cause ventricular overload.
Heart Sounds <ul><li>“ lub” is the sound of the atrioventricular valves closing </li></ul><ul><li>“ dub” is the sound of the semilunar valves closing </li></ul><ul><li>If a valve is not working well it produces a murmur (an “extra,” abnormal sound made by blood leaking through a malfunctioning valve). </li></ul>
Aortic Valve Stenosis <ul><li>When the valve narrows it can prevent blood from flowing in the right direction </li></ul>
hypertrophic cardiomyopathy - a disorder in which the heart muscle is so strong that it does not relax enough to fill the chambers with blood and so has reduced pumping ability hypertrophic cardiomyopathy (HCM) a form marked by ventricular hypertrophy, particularly of the left ventricle, with impaired ventricular filling due to diastolic dysfunction.
cardiomyopathy 1. a general diagnostic term designating primary non-inflammatory disease of the heart. 2. more restrictively, only those disorders in which the myocardium alone is involved and in which the cause is unknown and not part of a disease affecting other organs.
Echocardiogram - Echocardiogram is a test that uses sound waves to create a moving picture of the heart. The picture is much more detailed than X-ray image and involves no radiation exposure. This test is performed to evaluate the valves and chambers of the heart in a noninvasive manner. The echocardiogram allows doctors to evaluate heart murmurs, check the pumping function of the heart, and evaluate patients who have had heart attacks. It is a very good screening test for heart disease in certain groups of patients.
Medications to treat B.P. Vasoconstriction and Vasodilation