Abstract 4367505: Anti-inflammatory regimen associated with reduced incidence of early homograft stenosis following the Ross procedure

Background: The Ross procedure has favorable outcomes in young and middle-aged patients with aortic valve disease. However, one challenge is early-onset pulmonary homograft stenosis. Perivascular leukocytic infiltration on histology indicates an inflammatory etiology. Homograft upsizing has been shown to reduce the need for reintervention, but remains imperfect. Hypothesis: We hypothesized that a prophylactic anti-inflammatory regimen in addition to homograft upsizing would reduce the incidence of homograft stenosis following the Ross procedure. Methods: Data were collected retrospectively from patients who underwent the Ross procedure at our institution between 6/2020-10/2024. Patients who had surgery 12/2022 or later were prescribed a methylprednisolone taper and a non-steroidal anti-inflammatory drug (NSAID) for 6 months. Outcomes included at least moderate pulmonic stenosis (PS), defined as peak gradient 36 mmHg or higher, and need for re-intervention. Results: A total of 103 patients were included, with 55 in the standard group and 48 patients in the NSAID group. Baseline characteristics were similar between groups. Pulmonary homograft size was higher in the NSAID group (30 mm [IQR 28,31] vs 27 mm [IQR 26,27], p<0.001). There were no major bleeding events. Two patients discontinued NSAIDs due to side effects. The incidence of at least moderate PS was significantly higher in the standard group at 20.0% versus 6.25% in the NSAID group (p=0.042). Among those who completed 6 months of NSAIDs, only 1 patient had moderate PS (2.8%). Logistic regression demonstrated NSAID use was significantly associated with a lower likelihood of PS during follow-up (OR 0.171, CI 0.018, 0.749, p=0.016). Multivariate analysis was limited by study size. Reduction in incidence of PS persisted when patients were stratified by homograft size (Figure 1). In the standard group, 3 patients (5.4%) required pulmonic valve re-intervention. No patients in the NSAID group required re-intervention, although the difference was not significant (p=0.197, Figure 2). No patients in either group died or required aortic valve re-intervention. Conclusion: Implementation of an anti-inflammatory regimen in combination with pulmonary homograft upsizing was associated with a significantly lower incidence of homograft stenosis following the Ross procedure. No patients treated with the NSAID regimen have required pulmonic re-intervention, although longer follow-up will be needed to see if the difference persists.