Apparatus and methods are described including delivering a left-ventricular assist device to a subject's aorta. The device including a distal-tip element that defines a straight proximal portion, and a curved distal portion, the curved distal portion defining first and second curves with an elongated straight portion between the first and second curves. The distal-tip element is centered with respect to the aortic valve using the curved distal portion of the distal-tip element, to thereby guide the device through the subject's aortic valve atraumatically. A pump pumps blood through from the subject's left ventricle to the subject's aorta. Other applications are also described.