The case is reported of giant mitral valve vegetation that was wedged into the aortic valve plane (aortic valve 'kissing' vegetation), causing obstruction to the left ventricular outflow tract. In such a case, echocardiography plays a key role in the assessment of vegetation morphology, risk of embolization, impact on valvular function and indication for surgery. Because of its size, the obstructive hemodynamics, and the potential to induce aortic valve endocarditis, aortic 'kissing' vegetation requires surgical intervention to preserve the integrity of the valve and improve the hemodynamic status.