The diagnosis of pulmonary hypertension is easy during routine evaluation of patients with chronic heart failure by means of Doppler echocardiography. However, one must remember that an accurate hemodynamic characterization of the pulmonary circulation requires right heart catheterization to measure pulmonary vascular resistance and, if necessary, to test the reversibility of pulmonary hypertension. In addition, the importance of combining the right heart hemodynamic variables with a functional evaluation of the right ventricle is emphasized: in fact, the clinical impact of pulmonary hypertension in advanced heart failure patients (in terms of both exercise intolerance and prognosis) seems to be modulated by right ventricular function.