An implantable medical device configured for deployment at a ventricular septum of a patient's heart, the ventricular septum of the patient's heart having a right ventricle facing side and a left ventricle facing side, the IMD comprising: a housing having a proximal end and a distal end, the housing configured to be positioned at least in part in the right ventricle of the patient's heart with the distal end of the housing proximate the RV facing side of the ventricular septum once the IMD is implanted in the patient's heart; a power source disposed within the housing; circuitry disposed within the housing and operatively coupled to the power source; a first RV electrode adjacent the distal end of the housing and positioned to be facing the RV facing side of the ventricular septum once the IMD is implanted, the first RV electrode operatively coupled with the circuitry in the housing; a second RV electrode spaced proximally of the first RV electrode, the second RV electrode operatively coupled with the circuitry in the housing; an LV electrode positioned distally of the first RV electrode and at least partially in the ventricular septum once the IMD is implanted, the LV electrode operatively coupled with the circuitry in the housing; and an LV electrode position adjustment assembly for adjusting a distance that the LV electrode is positioned distally of the first RV electrode, wherein the LV electrode position adjustment assembly comprises a coupling secured relative to the housing, wherein the coupling is configured to mate with a separate adjustment tool that can move the coupling relative to the housing to adjust the distance that the LV electrode is positioned distally of the first RV electrode, characterized in that the IMD is a dual chamber leadless cardiac pacemaker. a housing having a proximal end and a distal end, the housing configured to be positioned at least in part in the right ventricle of the patient's heart with the distal end of the housing proximate the RV facing side of the ventricular septum once the IMD is implanted in the patient's heart; a power source disposed within the housing; circuitry disposed within the housing and operatively coupled to the power source; a first RV electrode adjacent the distal end of the housing and positioned to be facing the RV facing side of the ventricular septum once the IMD is implanted, the first RV electrode operatively coupled with the circuitry in the housing; a second RV electrode spaced proximally of the first RV electrode, the second RV electrode operatively coupled with the circuitry in the housing; an LV electrode positioned distally of the first RV electrode and at least partially in the ventricular septum once the IMD is implanted, the LV electrode operatively coupled with the circuitry in the housing; and an LV electrode position adjustment assembly for adjusting a distance that the LV electrode is positioned distally of the first RV electrode, wherein the LV electrode position adjustment assembly comprises a coupling secured relative to the housing, wherein the coupling is configured to mate with a separate adjustment tool that can move the coupling relative to the housing to adjust the distance that the LV electrode is positioned distally of the first RV electrode, characterized in that the IMD is a dual chamber leadless cardiac pacemaker.