Abstract: The present disclosure provides for a method for treating a patient in which a catheter having an electrode array is moved through the pulmonary trunk of the patient towards a branch point that helps to define the beginning of a left pulmonary artery and a right pulmonary artery of the heart. The electrode array is positioned in the right pulmonary artery where the electrodes contact a posterior surface, a superior surface and/or an inferior surface of the right pulmonary artery. The one or more electrodes can be positioned to contact the posterior surface, the superior surface and/or the inferior surface of the right pulmonary artery at a position superior to the branch point. The electrode array can also be positioned in the right pulmonary artery no more than three times the diameter of the pulmonary trunk to the right of the branch point.