Cellular Rejection Post-Cardiac Transplantation: A 13-Year Single Unicentric Study

Area of Science:

• Cardiology
• Transplantation Immunology
• Pathology

Background:

• Cardiac transplantation is the primary treatment for end-stage heart failure.
• Cellular rejection post-transplant significantly impacts patient morbidity and mortality.
• Understanding clinicopathologic factors in rejection mechanisms is crucial.

Purpose of the Study:

• To evaluate clinicopathologic factors influencing cardiac allograft rejection.
• To analyze histopathologic findings in post-transplant myocardial biopsies.
• To assess the prevalence and characteristics of rejection versus non-rejection lesions.

Main Methods:

• Retrospective analysis of 146 cardiac transplant recipients.
• Evaluation of myocardial function and structure via endomyocardial biopsy.
• Classification of acute cellular rejection (ACR) and antibody-mediated rejection (AMR) using ISHLT criteria.

Main Results:

• Most patients (82.2%) showed no rejection (ISHLT score 0).
• Non-rejection-related lesions were observed in 45.2% of cases.
• Ischemia-reperfusion lesions occurred in 25.3% of patients; mild inflammatory changes were frequent (71.9%).

Conclusions:

• While overt rejection is infrequent, non-rejection histopathologic changes are prevalent.
• Current rejection grading criteria may require adjustment to account for non-rejection lesions.
• Mononuclear inflammatory infiltrates, though often mild, are key indicators associated with rejection phenomena.