The anesthetist is increasingly faced with more complex operations in combination with an aging patient population characterized by pre-existing conditions. Acute right heart failure is often not recognized as the cause of cardiopulmonary insufficiency. Echocardiography has emerged as an important diagnostic tool. Not only perioperatively and in the intensive care unit, transesophageal (TEE) and transthoracic echocardiography (TTE) allow the diagnosis of right heart failure at bedside, promptly and with low invasiveness. Possible causes of right heart insufficiency on the level of afterload, preload and contractility can be clarified. Life-saving immediate measures can be initiated and, in addition, the success of the therapy can be visualized virtually "live". If indicated, a peri-/intraoperative echocardiographic examination also has a direct influence on therapy control. With a focused cardiac examination crucial information can be gained and the outcome of the patient can be positively influenced by adapted therapy control. By using standard ultrasound views, right heart failure can be detected as the cause of hemodynamic instability.