Abstract 14988: Incremental Value of Cardiac Magnetic Resonance Parameters to Predict Transplant-Free Survival in Fontan Patients
Background: Patients with a Fontan circulation have increased long-term mortality. The appropriate timing for heart transplantation referral remains controversial. In the absence of prior reports addressing the issue, this study sought to determine whether cardiovascular magnetic resonance (CMR) measurements of ventricular size and function improve risk stratification for transplant-free survival in Fontan patients.
Methods and Results: Clinical data on all Fontan patients who had a technically adequate CMR study from 4/2002 to 1/2011 were retrospectively reviewed. The primary endpoint was defined as time to death, listing for heart transplantation, or transplantation occurring after the CMR study. The Fontan patients (n=215) had a median age at CMR of 18.3 years [IQR 14, 26] and a median age at Fontan of 3.6 years [IQR 2, 7]. Twenty-four patients (11%) reached an endpoint (6 listed for transplantation and 18 deaths) at a median 2.5 years (range 0.1-6.8) after CMR. On univariate analysis, higher CMR derived indexed ventricular end-diastolic volume (EDVi), end-systolic volume, mass, and stroke volume were associated with the endpoint. A comparison of multivariate Cox regression models with clinical parameters only vs. clinical plus CMR parameters is summarized in the table. The clinical plus CMR parameter model with CMR derived EDVi showed a significantly higher likelihood ratio than the clinical parameter only model (P<0.001).
Conclusions: CMR derived EDVi is an independent predictor of death and heart transplantation in patients late after the Fontan operation and adds incremental value over clinical parameters alone for risk stratification. CMR evaluation of ventricular size and function has important additive predictive utility in this population.
- © 2013 by American Heart Association, Inc.