Background: Interventions to improve physical and psychological outcomes in recipients with an initial implantable cardioverter (ICD) and their intimate partners are largely unstudied, though likely to have a major impact on adjustment to the ICD and general well-being. Objective: To report the primary outcomes of the Patient Plus Partner randomized control trial. Methods: In a two-group (N=301) prospective RCT, we compared two social-cognitive-based intervention programs [Patient Plus Partner (P+P) and Patient Only (P only)], implementedfollowing initial ICD implant. The patient intervention, consisting of educational materials, nursedelivered telephone coaching, videotape demonstrations, and access to a nurse via a 24/7 pager, was implemented in both groups. P+P also incorporated partner participation. The primary patient outcomes were symptoms and anxiety at 3 months. Other outcomes were physical function (SF-36, ICD shocks-patient); psychological adjustment (PHQ-9); relationship impact (DAS, OCBS-partner); self-efficacy and knowledge (SCA-SE, SCA-OE, KSA); and health care utilization (outpatient visits, hospitalizations), at hospital discharge, 1, 3, 6, and 12 months post-ICD.Results: For patients, P+P compared to P Only was more effective in improving symptoms (P=0.02), depression (P=0.006), self-efficacy (P=.02), outcome expectations (P=0.03), and knowledge (P=0.07). For partners, P+P was more effective in improving partner caregiver burden (P=0.002), self-efficacy (P=0.001) and ICD knowledge (P=0.04).