Left ventricular (LV) failure can be divided into systolic and diastolic dysfunction. The former is characterized by a reduced ejection fraction and an enlarged LV chamber, the latter by an increased resistance to filling with increased filling pressures. Systolic dysfunction is clinically associated with left ventricular failure in the presence of marked cardiomegaly, while diastolic dysfunction is accompanied by pulmonary congestion together with a normal or only slightly enlarged ventricle. Echocardiography is currently the most relevant technique for non-invasive differentiation of the two forms. Systolic dysfunction is easily assessable by estimation of global ejection fraction and regional wall motion. Diastolic dysfunction can be diagnosed indirectly by means of a normal or nearly normal ejection fraction and and changes of the mitral filling pattern in the context of LV failure. For an exact determination of diastolic dysfunction LV catheterization is required. Systolic dysfunction treatment is well defined, consisting of ACE inhibitors, followed by diuretics and digitalis. Calcium channel blockers are usually contraindicated. Diastolic dysfunction therapy is more dependent on the underlying disease. Calcium channel blockers, ACE inhibitors or beta-blockers are first line drugs in most instances: diuretics can be added with increasing symptoms. Digitalis should be avoided, except in atrial fibrillation, to control heart rate.