[Posterior echocardiography windows: usefulness in clinical practice].

Posterior cardiac structures cannot always be imaged by means of standard transthoracic echocardiography. Left pleural effusion leading to pulmonary atelectasis and/or to displacement of air-filled pulmonary tissue displacement, allows ultrasound transmission from a patient's back to his heart through a liquid interface. In this study we present the clinical usefulness of echocardiographic posterior windows for the diagnosis of constrictive pericarditis and aortic dissection in 2 patients in whom the standard transthoracic approach did not permit diagnostic imaging. We conclude that, in the case of left pleural effusion, the use of posterior windows should be encouraged.