Study procedures: echocardiogram
Transthoracic echocardiography was performed using the IE33 Philips machine (Koninklijke Philips N.V., Netherlands) with 2D image acquisition with the Philips S5-1 transducer and harmonic imaging. Complete 2D transthoracic echocardiography was performed according to the recommendations of the American Society of Echocardiography (ASE)