According to some method embodiments, a left pulmonary artery electrode is positioned in a left pulmonary artery, and the left pulmonary artery electrode is used to sense atrial activity, or capture cardiac tissue, or deliver neural stimulation. According to some method embodiments, a right pulmonary artery electrode is positioned in a right pulmonary artery and a left pulmonary artery electrode is positioned in a left pulmonary artery, the right pulmonary artery electrode is used to sense atrial activity, or capture cardiac tissue, or deliver neural stimulation, and the left pulmonary artery electrode is used to sense atrial activity, or capture cardiac tissue, or deliver neural stimulation.