Myocardial perfusion is impaired in asymptomatic renal and liver transplant recipients: a cardiovascular magnetic resonance study

Abstract

BackgroundMyocardial ischemia is a major cause of death in chronic kidney disease (CKD) patients, which can be caused by either epicardial or microvascular coronary artery disease (CAD). Although renal transplantation improves survival, cardiovascular disease remains a major cause of mortality in post renal transplant recipients, including those with no significant epicardial CAD pre-transplant. We aim to utilize stress cardiovascular magnetic resonance (CMR) and MR coronary angiography (MRCA) to assess silent myocardial ischemia and epicardial CAD in renal transplant recipients.MethodsForty-five subjects: twenty renal transplant (RT) with no known CAD, fifteen liver transplant (LT) controls without prior CKD and no known CAD, and ten hypertensive (HT) controls underwent stress perfusion CMR and MRCA.ResultsA total of 1308 myocardial segments (576 of RT, 468 of LT, and 264 of HT) were compared using mixed linear modeling. Left ventricular mass index, septal diameter and presence of diabetes mellitus were similar between the groups. The mean transmural MPRI was significantly lower in the RT and LT groups compared to HT controls (1.19 ± 0.50 in RT versus 1.23 ± 0.36 in LT versus 2.04 ± 0.32 in HT controls, p < 0.0001), in the subepicardium (1.33 ± 0.57 in RT versus 1.30 ± 0.33 in LT versus 2.01 ± 0.30 in HT controls, p < 0.001), and in the subendocardium (1.19 ± 0.54 in RT versus 1.11 ± 0.31 in LT versus 1.85 ± 0.34 in HT controls, p < 0.0001). Seven (35 %) RT and five (33 %) LT had significant epicardial CAD compared to none in HT controls, p = 0.12. One RT and one LT had LGE suggesting sub-endocardial infarction.ConclusionsRT recipients have impaired myocardial perfusion independent of LVH or diabetes mellitus. The impaired myocardial perfusion in RT is similar to LT without prior renal disease, thus unlikely related to previous CKD. It is not fully explained by the presence of significant epicardial CAD, and therefore most likely represents microvascular CAD.

Coronary artery calcium burden, carotid atherosclerotic plaque burden, and myocardial blood flow in patients with end-stage renal disease: A non-invasive imaging study combining PET/CT and 3D ultrasound

“…This finding supports the assumption that the duration of renal replacement therapy has a strong impact on myocardial perfusion, mainly due to rarefication of small intramyocardial vessels. 23 – 25 We found impaired CFR in 20% of our patients, which is less than reported in other studies 33 and most probably due to the relatively young study cohort. Prior investigations have suggested that CKD is associated with abnormal coronary vasodilator function, 26 which results from multiple mechanisms including decreased capillary density, 27 vascular remodeling, 28 and endothelial dysfunction.…”

Preoperative Evaluation of Coronary Artery Disease in Liver Transplant Candidates: Many Unanswered Questions in Clinical Practice

“…The spatial resolution of CMR myocardial perfusion (using most commonly adenosine) is superior to other imaging modalities, such as nuclear techniques, so that subendocardial ischemia can be more reliably identified [ 31 , 63 ]. Myocardial perfusion abnormalities can be attributed either to epicardial CAD or to microcirculation disorders, which are frequently present in LT candidates [ 64 ]. If CMR stress examination does not show ischemia in LT candidates, the 12-month event free survival rate is almost 100% [ 65 ].…”

Cardiac Imaging in Liver Transplantation Candidates: Current Knowledge and Future Perspectives

“…Its high diagnostic accuracy in coronary heart disease and superiority over SPECT was established by the Clinical Evaluation of MAgnetic Resonance imaging in Coronary heart disease (CE-MARC) study [117]. Myocardial perfusion abnormalities can be attributed to epicardial CAD or microcirculation disorders and is frequently abnormal in cirrhotic patients [118]. A negative for ischemia CMR stress examination in LT candidates has been shown to have an almost 100% CAD event free survival at 12 months [119].…”