A delivery method and system for noninvasively monitoring cardiac physiologic parameters used to evaluate patients with cardiovascular conditions. The system includes an implantable sensing device configured for chronic implantation in a cavity of the cardiovascular system, such as the heart, pulmonary artery (PA), etc. The method involves introducing the sensing device through a cardiovascular cavity that is upstream in the vasculature from the cavity where implantation is intended and has a larger diameter than the intended cavity, and thereafter blood flow through the cardiovascular system delivers the device to the intended cavity. The device is sized and configured so as to secure itself within the intended cavity when the device moves through the cavity to a point where the diameter narrows sufficiently to secure the device and so as to be oriented once secured to sense a pressure either within, upstream (wedge), or downstream (distal) of the cavity.