:Pulmonary edema refers to the accumulation of abnormal amounts of fluid in the extravascular spaces of the lungs.<br /><br /> There are many causes for pulmonary edema. However, it is common clinical manifestation of left ventricular heart failure. Pressures rise in the left atrium and ventricle to compensate for the failure and this causes increased pressure in the pulmonary vasculature. Incrased pulmonary capillary pressure relative to the plasma oncotic pressure cause fluid to leave the vessels and enter the interstitial spaces of the lung.

:Pleural effusion is the presence of fluid in the pleural space.<br /><br /> Increased hydrostatic pressure in the pulmonary vasculature, as seen in heart failure, is one cause of pleural effusion.

:Aortic stenosis (calcification of the aortic valve) is the most common valve abnormality.<br /><br /> Calcification of the valve leads to a reduced valve area. Increased pressure is thus needed from the left ventricle to pump blood into the aorta. Over time, the pressure-overloaded ventricle hypertrophies concentrically (increased ratio of wall thickness to cavity radius) in an attempt to reduce wall tension (review the Law of Laplace).<br /><br /> Eventually, the left ventricle's contractile capacity is overwhelmed by the stiffness of the ventricle (due to hypertrophy) and pressure begins to increase through the left atrium and into the pulmonary vasculature. Increased pulmonary artery pressures then lead to right ventricular failure.

:Aortic insufficiency refers to the inability of the aortic valve to close properly, thus allowing regurgitation of blood into the left ventricle during diastole -- i.e., volume overload.<br /><br /> Disease of the aortic valve leaflets is a common cause of insufficiency.