After liver transplant, veno-occlusive disease and infectious complications may result from subclinical pulmonary hypertension. In this retrospective study, we investigated whether our preemptive bundle therapy was effective for subclinical pulmonary hypertension and extrasinusoidal platelet aggregation after liver transplant. After January 2014, nutrition therapy with glutamine, synbiotics, phosphodiesterase 3 inhibitors, prostaglandin E1, prostaglandin I2, closedloop artificial pancreas, and sivelestat has been used to reduce bacterialtranslocation, vascular endothelial cell damage, and extrasinusoidal platelet aggregation, which is administered as preemptive bundle therapy for all livertransplantrecipients. In this study, we evaluated the prognosis of 84 liver transplant recipients who underwent liver transplants through 2018. Subclinical pulmonary hypertension was evaluated in 49 adult liver transplant recipients with an evaluable main pulmonary artery trunk cross-sectional area using enhanced computed tomography in the acute phase after transplant, with 14 of these patients receiving preemptive bundle therapy. Subclinical pulmonary hypertension was reduced in the preemptive bundle therapy group (n = 14) compared with the nontherapy group (n = 35). The preemptive bundle therapy group showed more rapid recovery of platelet, prothrombin time, and bilirubin levels afterlivertransplant compared with the nontherapy group. The prognosis of patients in the preemptive bundle therapy group was significantly better than in the nontherapy group. Extrasinusoidal platelet aggregation was significantly lower in the preemptive bundle therapy group than in the nontherapy group. Preemptive bundle therapy reduced sinusoidal endothelial cell injury, extrasinusoidal platelet aggregation, and subclinical pulmonary hypertension after liver transplant, resulting in good posttransplant recovery.