Continuous-wave Doppler echocardiography is an accurate method for the non-invasive estimation of pulmonary artery pressure because the pressure gradient across a regurgitant valve can be estimated accurately by measuring the high flow velocity of the regurgitant jet and by applying the simplified Bernoulli equation. Measurable tricuspid and/or pulmonary regurgitation can be observed in a great percentage of patients with heart failure (approximately 90% of patients if the examination is performed by an experienced sonographer) and the method has a wide clinical applicability. Recently, new attention has been focused on the possibility of evaluating the right ventricular function by echocardiography. Although the measurement of the volumes of this cardiac chamber is undoubtedly difficult with ultrasound (as it is with most imaging techniques), it must be recognized that echocardiography allows for the measurement of simple M-mode and two-dimensional parameters which are extremely useful in the prognostic stratification of patients with congestive heart failure.