A method of facilitating therapeutic neuromodulation of a heart of a patient includes positioning an electrode in a pulmonary artery, positioning a sensor in vasculature, delivering via a stimulation system first and second electrical signals of a series of electrical signals to the electrode. The second electrical signal differs from the first electrical signal by a magnitude of a first parameter of a plurality of parameters. The method includes determining, via the sensor, sensor data indicative of one or more heart activity properties in response to the delivery of the series of electrical signals, and delivering a therapeutic neuromodulation signal to the pulmonary artery using selected electrical parameters. The selected electrical parameters include a selected magnitude of the first parameter. The selected magnitude of the first parameter is based at least partially on the sensor data. The therapeutic neuromodulation signal increases heart contractility.
