Abstract 10276: Combined Stress Cardiac Magnetic Resonance and Liver Imaging for Liver Transplant Candidates; a Proof of Concept Approach
Background Preoperative imaging of liver transplant (LvTx) candidates can be cumbersome, time-consuming and expensive, due to need to perform separate echocardiogram, stress test, and liver/vascular imaging. In addition, cardiovascular (CV) risk stratification using traditional modalities has proven challenging in these patients. Over the last decade cardiovascular MRI (CMR) has emerged as the 'gold standard' for many important CV metrics used to define CV risk due to its unparalleled spatial resolution, lack of ionizing radiation, 3D capabilities, and tissue characterization.
Hypothesis We demonstrate the feasibility of performing a comprehensive preoperative cardio-hepatic evaluation in LvTx candidates as a ‘one-stop shop’ in a dedicated CMR suite.
Methods In this pilot study, pts underwent LV/RV function assessment (SSFP), stress CMR, and thoracoabdominal MRI/MRA. Pharmacologic stress CMR was done via regadenoson, adenosine, or dobutamine. Viability was assessed by LGE. Cardiologists managed pts during acquisition and interpreted CMR studies. Diagnostic radiologists only interpreted abdominal MRI/A.
Results Over 2yrs, 72 LvTx candidates (56±7 years, 35% female; mean MELD score of 15, Child-Pugh Class ≥ B) underwent CMR with an average imaging time of 72±23mins. This included 7 pts on mechanical ventilation and 6 on vasopressors for shock. All pts completed SSFP, 98% completed stress CMR, 82% completed DHE viability (3 renal failure pts underwent dobutamine CMR), 94% completed liver MRI, and 88% completed MRA. Four pts had coronary angiograms and none of these had flow-limiting coronary disease. Nine pts underwent orthotopic LvTx (mean 74 days to LvTx after MRI). There were 7 ascertained deaths in the non-LvTx group (mean 23 days post CMR) and 1 death in the LvTx group (116 days after MRI, 11 days after LvTx). Using conservative estimates by Medicare CMS/OPPS and payment rates (professional+technical), average cost saving was $181/pt via Q3 APC codes. In addition, > 2 days of additional testing days were saved per pt.
Conclusion It is feasible, efficient and safe to perform comprehensive preoperative liver transplant imaging in a CMR suite, even in critically ill patients. Future evaluations will focus on prognostic accuracy of this approach.
- © 2011 by American Heart Association, Inc.