Outcome of patients having heart transplantation for lymphocytic myocarditis

Area of Science:

• Cardiology
• Transplantation Immunology
• Pathology

Background:

• Heart transplantation (HT) for myocarditis remains controversial due to historical concerns about post-procedural prognosis.
• Assessing the impact of lymphocytic myocarditis (LM) on cardiac allograft rejection and survival in the current era of HT is crucial.

Purpose of the Study:

• To evaluate if lymphocytic myocarditis (LM) in explanted hearts influences cardiac allograft rejection and survival post-heart transplantation (HT).
• To compare outcomes of HT patients with LM against those with idiopathic dilated cardiomyopathy (IDC) and ischemic cardiomyopathy (IC).

Main Methods:

• Retrospective review of 759 consecutive de novo HT patients (2000-2010).
• Comparison of prognosis between patients with pathologically proven LM (n=32) and matched IDC (n=96) and IC (n=64) groups.
• Analysis of biopsy-diagnosed acute cellular rejection (ACR) and antibody-mediated rejection, alongside posttransplant survival rates.

Main Results:

• No significant difference in first-year acute cellular rejection (ACR) events among the three groups.
• Increased frequency of late ACR (after the first year) observed in the LM group compared to the IC group (3.8% vs. 0.5%, p=0.006).
• No significant differences in antibody-mediated rejection or overall posttransplant survival among the LM, IDC, and IC groups.

Conclusions:

• Patients with pre-HT LM exhibit a higher rate of late ACR post-transplantation compared to those with IC.
• Long-term survival after HT for LM is comparable to that for IDC and IC, suggesting HT is a viable option.
• LM should be considered in pre-transplant evaluations, with awareness of potential late rejection episodes.