ABSTRACT
BACKGROUND: Our aim was to determine if end-stage liver disease (ESLD) is associated with an attenuated response to vasodilator-stress or dobutamine-stress using 82Rb-PET MPI with blood flow quantification. METHODS AND RESULTS: Pre-liver transplant patients who had a normal dipyridamole-stress (n = 27) or dobutamine-stress (n = 26) 82Rb PET/CT MPI study with no identifiable coronary artery calcium were identified retrospectively and compared to a prospectively identified low-risk of liver disease dipyridamole-stress control group (n = 20). The dipyridamole-stress liver disease group had a lower myocardial flow reserve (MFR) (1.89 ± 0.79) than the control group (2.79 ± 0.96, P < .05). The dobutamine-stress group had a higher MFR than both other groups (3.69 ± 1.49, P < .05). A moderate negative correlation between MELD score and MFR was demonstrated for the dipyridamole-stress liver disease group (r = - 0.473, P < .05). This correlation was not observed for the dobutamine-stress liver disease group (r = - 0.253, P = .21). The liver failure group as a whole (n = 53) had a higher resting myocardial blood flow (0.97 ± 0.33 mL/min/g) than the control group (0.82 ± 0.26, P < .05). CONCLUSION: Dipyridamole demonstrates an attenuated vasodilatory response in ESLD patients compared to a non-ESLD control group related to higher resting blood flow and comparatively reduced stress blood flow. Dobutamine does not demonstrate this effect implying it may be the preferred pharmacologic MPI stress agent for ESLD patients.
Subject(s)
Dobutamine , End Stage Liver Disease/diagnostic imaging , Liver Failure/diagnostic imaging , Myocardial Perfusion Imaging/methods , Positron Emission Tomography Computed Tomography/methods , Rubidium Radioisotopes , Vasodilation , Adult , Aged , Coronary Circulation/physiology , Dipyridamole , Female , Humans , Liver Failure/surgery , Liver Transplantation , Male , Middle Aged , Prospective Studies , Regression Analysis , Retrospective Studies , Severity of Illness Index , Vasodilator AgentsABSTRACT
OBJECTIVE: The goals of our study were to retrospectively review our experience in using Tc-white blood cell (WBC) single-photon emission computed tomography/computed tomography (SPECT/CT) imaging in the evaluation of possible arterial graft infection and to attempt to establish objective criteria for assessment. METHODS: Eleven Tc-WBC SPECT/CT studies performed for the evaluation of clinically suspected arterial graft infection were retrospectively reviewed and compared with reference outcomes. In an attempt to define objective criteria for interpretation, comparison was also made with background liver and bone marrow activity. RESULTS: When compared with reference outcomes, the subjective scan interpretations showed 6 of 11 true positives (TP), 4 of 11 true negatives (TN), and 1 of 11 false positive (FP). Using the liver as a comparator resulted in 4 of 10 TP, 5 of 10 TN, and 1 of 10 FN. Using the bone marrow as a comparator resulted in 3 of 10 TP, 5 of 10 TN, and 2 of 10 FN. In one patient neither the liver nor the bone marrow was in the field of view. CONCLUSION: These findings suggest a high accuracy for Tc-WBC SPECT/CT in assessing clinically suspected arterial graft infection. Furthermore, the liver may be the best objective comparator for standardized interpretation.
