Left-sided heart failure builds pressure into the pulmonary veins and eventually increases blood pressure in the right ventricle. As this pressure increases, the right ventricle has to work harder to accommodate it, leading to hypertrophy or dilation. This is known as cor pulmonale. Pressure will eventually build into systemic venous circulation. This may increase portal vein pressure leading to portal vein hypertension, which can lead to ascites, peripheral oedema and varices.