Intravascular devices and systems useful for blocking the opening of an aneurysm or a vessel branch are disclosed. In some aspects, the disclosure provides arrangements that align a covering material of a stent graft with an opening in the vessel wall before, during, and/or after expansion of the stent graft within the vasculature of a patient. In some instances, systems and devices include a sheath with a side aperture arranged to align a portion of the sheath and/or a portion of a stent graft contained within the sheath with the mouth of an aneurysm. Similarly, the present disclosure also provides embodiments in which the stent graft comprises an aligning member arranged to align the stent graft and/or a sheath with the mouth of an aneurysm. Other embodiments are disclosed.
