Transplant Trial Watch

Cardiovascular Magnetic Resonance for Rejection Surveillance After Cardiac Transplantation.

Anthony, C., et al.

Circulation 2022; 145(25): 1811-1824.


Aims
The aim of this study was to investigate the feasibility of cardiovascular magnetic resonance (CMR)-based monitoring for cardiac allograft rejection.

Interventions
Participants were randomised to receive either CMR-based or endomyocardial biopsy (EMB)-based rejection surveillance.

Participants
40 orthotopic heart transplant recipients.

Outcomes
The primary endpoint was frequency and cumulative freedom from significant (> grade 2R) rejection. The secondary endpoints included frequency and cumulative freedom from low-grade (grade 1R) rejection, kidney function, hospitalisation, duration of hospital stay, infection, myocardial function, death, immunosuppression exposure and the incidence of biopsy-related complications.

Follow-up
1 year

CET Conclusions
This is an interesting and well-conducted study in cardiac allotransplantation. Cardiac magnetic resonance (CMR) imaging was compared to the standard protocol of surveillance for rejection with the invasive endomyocardial biopsy (EMB). The first part of the study was a cross-sectional analysis to understand cut-off values for acute rejection and the second part was a randomised study comparing the two surveillance methods using this information. The trial was set up as a noninferiority study and therefore the inclusion did not need to be large (20 in each arm), as per prior power calculation. A detailed analysis of the CMR validation is provided. The primary endpoint was frequency of significant rejection (grade 2R or higher). This was found to be similar in the two groups. In order not to miss high grade rejection, treating physicians could request EMB on any patient at their discretion. This option was taken 11 times in the CMR group and in 9 of these cases the EMB result was identical to the CMR result. In this single-centre study, a surveillance protocol using CMR instead of EMB in cardiac allograft recipients was safe, feasible and offers significant advantages over invasive cardiac biopsies.

Jadad score
3

Data analysis
Strict intention-to-treat analysis

Allocation concealment
Yes

Trial registration
ACTRN12618000672257

Funding source
Non-industry funded