Evaluation Of Cardiac Allograft Vasculopathy Research Articles

Longitudinal Change and Predictors of Myocardial Flow Reserve by Positron Emission Tomography for the Evaluation of Cardiac Allograft Vasculopathy Following Heart Transplantation

Background: PET myocardial flow reserve (MFR) is a noninvasive method to detect cardiac allograft vasculopathy in heart transplant (HT) recipients. There is limited data on longitudinal change and predictors of MFR following HT. Methods: We conducted a retrospective analysis of HT recipients undergoing PET MPI at an academic center. Multivariable linear and Cox regression models were constructed to identify longitudinal trends, predictors, and prognostic value of MFR after HT. Results: 183 HT recipients underwent 658 PET studies. Average MFR was 2.34 ± 0.70. MFR initially increased in the first three years following HT (+0.12 per year, P = 0.01) before beginning to decline at an annual rate of -0.06 per year (P <0.001). MFR declines preceding acute rejection and improves after treatment. Treatment with mTOR inhibitors (37.2%) slowed the rate of annual MFR decline (P = 0.03). Higher-intensity statin therapy was associated with improved MFR. Longer time post-transplant (p <0.001), hypertension (P <0.001), chronic kidney disease (P < 0.001), diabetes mellitus (P = 0.038), antibody-mediated rejection (P = 0.040), and cytomegalovirus infection (P = 0.034) were associated with reduced MFR. Reduced MFR (HR: 7.6, 95% CI: 4.4-13.4, P <0.001) and PET-defined ischemia (HR: 2.3, 95% CI: 1.4-3.9, P <0.001) was associated with a higher risk of the composite outcome of mortality, retransplantation, heart failure hospitalization, acute coronary syndrome, or revascularization. Conclusion: MFR declines after the third post-transplant year and is prognostic for cardiovascular events. Cardiometabolic risk factor modification and treatment with higher-intensity statin therapy and MTI are associated with a higher MFR.

PET Myocardial Blood Flow for Post-transplant Surveillance and Cardiac Allograft Vasculopathy in Heart Transplant Recipients.

Cardiac allograft vasculopathy (CAV) is a late-occurring complication of heart transplantation significantly limiting overall graft survival. In the last few years, evidence has been growing about the use of positron emission tomography (PET) myocardial perfusion imaging with integrated myocardial blood flow (MBF) quantification in heart transplant recipients. Multiple studies have demonstrated that PET MBF assessment can be utilized to establish the diagnosis of CAV noninvasively and can be employed for prognostication. PET MBF quantification has also helped to define the link between transplant rejection and CAV. In addition, limited data suggests that PET MBF quantification can be used in heart transplant patients for serial monitoring of CAV. PET myocardial perfusion imaging integrating MBF quantification shows great promise for the evaluation of CAV with good diagnostic and prognostic performance.

Validation of a semi-automatic software for optical coherence tomography - analysis in heart transplanted patients.

Optical Coherence Tomography (OCT) is an intravascular imaging modality enabling detailed evaluation of cardiac allograft vasculopathy (CAV) after heart transplantation (HTx). However, its clinical application remains hampered by time-consuming manual quantitative analysis. We aimed to validate a semi-automated quantitative OCT analysis software (Iowa Coronary Wall Analyzer, ICWA-OCT) to improve OCT-analysis in HTx patients. 23 patients underwent OCT evaluation of all three major coronary arteries at 3months (3M) and 12months (12M) after HTx. We analyzed OCT recordings using the semiautomatic software and compared results with measurements from a validated manual software. For semi-automated analysis, 31,228 frames from 114 vessels were available. The validation was based on a subset of 4287 matched frames. We applied mixed model statistics to accommodate the multilevel data structure with method as a fixed effect. Lumen (minimum, mean, maximum) and media (mean, maximum) metrics showed no significant differences. Mean and maximum intima area were underestimated by the semi-automated method (β-methodmean = -0.289 mm2, p < 0.01; β-methodmax = -0.695 mm2, p < 0.01). Bland-Altman analyses showed increasing semi-automatic underestimation of intima measurements with increasing intimal extent. Comparing 3M to 12M progression between methods, mean intimal area showed minor underestimation (β-methodmean = -1.03 mm2, p = 0.04). Lumen and media metrics showed excellent agreement between the manual and semi-automated method. Intima metrics and progressions from 3M to 12M were slightly underestimated by the semi-automated OCT software with unknown clinical relevance. The semi-automated software has the future potential to provide robust and time-saving evaluation of CAV progression.

Non-invasive Imaging in the Evaluation of Cardiac Allograft Vasculopathy in Heart Transplantation: A Systematic Review.

Cardiac allograft vasculopathy (CAV) is the leading cause of long-term graft dysfunction in patients with heart transplantation and is linked with significant morbidity and mortality. Currently, the gold standard for diagnosing CAV is coronary imaging with intravascular ultrasound during traditional invasive coronary angiography. Invasive imaging, however, carries increased procedural risk and expense to patients in addition to requiring an experienced interventionalist. With the improvements in non-invasive cardiac imaging modalities such as transthoracic echocardiography, computed tomography, magnetic resonance imaging and positron emission tomography, an alternative non-invasive imaging approach for the early detection of CAV may be feasible. In this systematic review, we explored the literature to investigate the utility of non-invasive imaging in diagnosis of CAV in >3000 patients across 49 studies. We also discuss the strengths and weaknesses for each imaging modality. Overall, all 4 imaging modalities show good to excellent accuracy for identifying CAV with significant variations across studies. Majority of the studies compared non-invasive imaging with invasive coronary angiography without intravascular imaging. In summary, non-invasive imaging modalities offer an alternative approach to invasive coronary imaging for CAV. Future studies should investigate longitudinal non-invasive protocols in low-risk patients after heart transplantation.

Echocardiography Surveillance of Rejection after Heart Transplant without Endomyocardial Biopsy

Purpose Surveillance for acute rejection (AR) and cardiac allograft vasculopathy ( CAV) is essential for graft and patient survival. CAV can arise and progress without symptoms and subclinical AR can facilitate CAV .Standard surveillance of AR and CAV is based on routine endomyocardial biopsies (EMBs) and coronary angiographies (CA) at predefined intervals , 9 to 13 times during first post transplant year , there after 3-4 biopsy annually . These invasive screening tests are distressing ,costly and not without complications , yet they cannot identify all sub-clinical ARs . We adopted Biospy free Echocardiography surveillance for detection and treatment of Rejection . Methods From June 2016 till August 2020 , 12 heart transplant recipients,7 male and 5 female , were followed by Echocardiography with Doppler Tissue / strain imaging every 3 months or earlier if indicated. Routine Complete Blood Count , Renal &Liver Function test, Cyclosporine or Tacrolimus level also done .Eleven recipients are free of any rejection.Total Echo-surveillance follow up in study is > 510 months. Results Doppler tissue-imaging (DTI) and strain-imaging for myocardial wall motion and deformation analysis, allowed quantification of minor myocardial dysfunction for early detection of subclinical AR and CAV. Two patients had mild rejection Grade IIB were treated by increasing dose of steroid and raising level of Calcineurine inhibitor. One recipient found to have acute rejection on Echocardiography ,EMB, proved grade III rejection ,treated with Methyl prednisolone, Anti-thymic antibody Conclusion DTI and strain-imaging is an important tool enabling more efficient AR monitoring with fewer EMBs instead of routine EMB-screenings. Myocardial velocity and deformation imaging is also allows early detection of myocardial dysfunction induced by CAV, prognostic evaluation of CAV and timing of CAs aimed to reduce the number of routine CA-screenings. Donor specific antibody with protocol Echocardiography or same in symptomatic patients can yield good surveillance without endomyocardial biopsy.

Serial evaluation of cardiac allograft vasculopathy after heart transplantation by dual-modality intravascular ultrasound and optical coherence tomography

Abstract Background Cardiac allograft vasculopathy is a combination of the development of de novo plaque and the progression of donor-transmitted plaque. Purpose This study aimed to evaluate the development of de novo plaque and the progression of donor-transmitted plaque within 12-month after heart transplantation (HTx) using serial intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The association between inflammatory cytokines and plaque progression was also examined. Methods We prospectively enrolled 40 recipients to conduct serial three-vessel IVUS and OCT analysis at 8-week and 12-month after HTx. De novo plaque was defined as having maximum intimal thickness (MIT) ≥0.5 mm at 12-month in the absence of donor-transmitted plaques (MIT ≥0.5 mm at 8-week). Serum cytokines were screened with a bead-based multiplex assay. Results A total of 13 de novo plaques (fibrous, n=10; fibroatheroma, n=3) were detected in eight recipients. Serum interleukin (IL)-31 at 8-week was associated with the development of de novo plaques (p=0.009). A total of 31 donor-transmitted plaques (fibrous, n=12; fibroatheroma, n=11; fibrocalcific, n=8) were detected in 17 recipients. Multiple regression analysis revealed that fibrous (p=0.026) and fibroatheroma (p=0.012) observed at 8-week were significantly associated with subsequent plaque progression within 12-month after HTx. ΔPlaque burden was significant higher in de novo plaque than donor-transmitted plaque (38.8% [29.6–41.2] versus 8.7% [1.3–13.6], p&amp;lt;0.001). The prevalence of macrophage accumulation was lower in de novo plaque than in donor-transmitted plaque (8% versus 52%, p=0.006). Serum IL-31 at 8-week was correlated with the progression of donor-transmitted plaque as well as de novo plaque (r=0.663, p=0.029) although other cytokines like IL-1β, IL-6, IL-17, and tissue necrotic factor alpha were not. Conclusions In de novo plaques, fibrous plaque was the most common and macrophage accumulation was rarely observed. In donor-transmitted plaque, fibrous and fibroatheroma were independent predictor for the subsequent plaque progression. Serum interleukin-31 surge at subacute phase may play pathogenic role in cardiac allograft vasculopathy. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grants-in-Aid for Scientific Research (KAKENHI)

Quantitative coronary computed tomography angiography for the detection of cardiac allograft vasculopathy

ObjectivesTo associate coronary wall volume and composition, derived from coronary computed tomography angiography (CTA), with cardiac allograft vasculopathy (CAV) detected on invasive coronary angiography (ICA) in heart-transplanted (HTX) patients.MethodsWe included consecutive adults who received ICA and coronary CTA for evaluation of CAV ≥ 10 months after HTX. In all coronary segments, we assessed lumen and wall volumes and segmental length, calculated volume-length ratio (VLR) (volumes indexed by segmental length; mm3/mm), wall burden (WB) (wall/wall + lumen volumes; %), and assessed proportions of calcified, fibrotic, fibro-fatty, and low-attenuation tissue (%) in coronary wall. We rendered independent CTA measures associated with CAV by ICA, tested their discriminatory capacity, and assessed concordance between CTA and ICA.ResultsAmong 50 patients (84% men; 53.6 ± 11.9 years), we analyzed 632 coronary segments. Mean interval between HTX and CTA was 6.7 ± 4.7 years and between ICA and CTA 1 (0–1) day. Segmental VLR, WB, and proportion of fibrotic tissue were independently associated with CAV (OR = 1.06–1.27; p ≤ 0.002), reaching a high discriminatory capacity (combination of all three: AUC = 0.84; 95%CI, 0.75–0.90). Concordance between CTA and ICA was higher in advanced CAV (88%) compared with that in none (37%) and mild (19%) CAV. Discordance was primarily driven by a large number of segments with coronary wall changes on CTA but without luminal stenoses on ICA (177/591; 25%).ConclusionCTA-derived coronary wall VLR, WB, and the proportion of fibrotic tissue are independent markers of CAV. Combination of these three parameters may aid the detection of early CAV not detected by ICA, the current standard of care.Key Points• Coronary CTA detects CAV in HTX patients.• Coronary wall volume-length ratio, wall burden, and proportion of fibrotic tissue are independently associated with CAV.• In contrast to ICA, coronary CTA may identify the early stages of CAV.

Intravascular Imaging for Assessment of Cardiac Allograft Vasculopathy Following Heart Transplantation

Cardiac allograft vasculopathy (CAV) is a significant cause of morbidity and mortality in the post-cardiac transplant patient population. Current guidelines recommend annual angiographic surveillance for CAV; however, angiography alone has several limitations and can lead to systematic underestimation of disease burden and the inability to sensitively track disease progression. We provide an overview of intravascular imaging in the initial and longitudinal evaluation of CAV, with a focus on the use of intravascular ultrasound (IVUS). Multiple studies have demonstrated that progression of maximal intimal thickness (MIT) on serial IVUS evaluation, particularly ≥ 0.5 mm over the first year, post-transplant, is predictive of both future development of angiographically significant CAV as well as major adverse cardiac events, including graft loss and mortality. There are also emerging data that in vivo plaque characterization, as assessed by the attenuated-signal plaque score or by virtual histology intravascular ultrasound (VH-IVUS), may provide prognostic value in this population. OCT-derived intimal measurements have been noted to correlate well with IVUS findings and may also aid in early identification of CAV. In addition to early identification and prognostication, several studies have used intravascular imaging to assess therapeutic impact of various immunosuppressive regimens on progression of established CAV. Intravascular ultrasound, and more recently, optical coherence tomography (OCT) have emerged as valuable adjuncts to angiography in the evaluation of CAV, particularly with regard to early detection, objective prognostication, and differentiation of CAV from donor-derived coronary artery disease (CAD). Furthermore, intravascular imaging may guide changes to the immunosuppressive regimen and/or percutaneous coronary intervention, when necessary.

Prediction of long-term (> 10 year) cardiovascular outcomes in heart transplant recipients: Value of stress technetium-99m tetrofosmin myocardial perfusion imaging

BackgroundMyocardial perfusion imaging (MPI) using single-photon emission computed tomography (SPECT) is useful in the evaluation of cardiac allograft vasculopathy (CAV) in heart transplant (HTx) recipients. The current study evaluated the long-term prognostic value of stress SPECT MPI for predicting all-cause mortality and cardiac events in HTx recipients. MethodsThe study population consisted of 166 HTx recipients (mean age 54 ± 10 years, 84% male) who underwent exercise or dobutamine stress 99mTc-tetrofosmin SPECT MPI for the assessment of CAV. An abnormal SPECT MPI was defined as the presence of a fixed or a reversible perfusion defect. Endpoints were all-cause mortality, cardiac mortality, and non-fatal myocardial infarction (MI). ResultsMPI abnormalities were detected in 55 patients (33%), including fixed defects in 28 patients (17%), partially reversible in 17 patients (10%), and completely reversible defects in 10 patients (6%). During a median follow-up of 12.8 years (range 0-15, mean follow-up 9.5 years), 109 (66%) patients died (all-cause mortality), of which 67 (40%) were due to cardiac causes. A total of 5 (3%) patients experienced a non-fatal MI. HTx recipients with a normal stress 99mTc-tetrofosmin SPECT MPI had a significantly better prognosis as compared with those with an abnormal study, up to 5 years after the initial test. The presence of a reversible perfusion defect was a significant predictor of all-cause mortality, cardiac mortality, and major cardiac events, during the entire follow-up period. ConclusionsStress 99mTc-tetrofosmin SPECT MPI provides valuable prognostic information for the prediction of long-term outcome in HTx recipients. Patients with a normal stress 99mTc-tetrofosmin SPECT MPI have a significantly better prognosis as compared with those with an abnormal study, up to 5 years after initial testing.

Quantification of PET Myocardial Blood Flow.

The aim of this review is to provide an update on quantification of myocardial blood flow (MBF) with positron emission tomography (PET) imaging. Technical and clinical aspects of flow quantification with PET are reviewed. The diagnostic and prognostic values of myocardial flow quantification have been established in numerous studies and in various populations. MBF quantification has also shown itself to be particularly useful in the assessment of coronary microvascular dysfunction and in evaluation of cardiac allograft vasculopathy. Overall, myocardial flow reserve (MFR) and hyperemic MBF can lead to improved risk stratification by providing information complementary to that of other markers of disease severity, such as fractional flow reserve. Flow quantification enhances MPI's ability to detect both significant epicardial disease and microvascular dysfunction. With recent technological and methodological advances, flow quantification with PET is no longer restricted to cyclotron-equipped academic centers.

Novel Cytokine Score and Cardiac Allograft Vasculopathy

To date, there are no established noninvasive biomarkers available for prediction of cardiac allograft vasculopathy (CAV) after orthotopic heart transplantation (OHT). Inflammatory processes are supposed to play a central role in the pathogenesis of CAV. Recent studies have suggested that immune mediators could serve as biomarkers for cardiovascular diseases. We hypothesized particular cytokines or a combination thereof may serve as noninvasive biomarkers for CAV. Plasma cytokines were screened from 27 patients with CAV and 27 patients without CAV after OHT. The concentrations of interleukins-4, -6, -10, -21, -23, -31, -33, interferon gamma, tumor necrosis factor alpha, and the soluble activation marker CD40 ligand were determined using Luminex-based multiplex analyses. Although concentrations of all cytokines except interferon gamma were on average higher in the CAV group, there were no significant differences between the groups for any 1 cytokine. Using a binary logistic regression model, we were able to develop a probability score for detecting patients at elevated risk for advanced CAV with a sensitivity of 92.31% and a specificity of 60.71% (receiver-operating characteristic area under the curve 0.799 ± 0.06; p<0.0001). In conclusion, analyzing the concentration of specific inflammatory cytokines could be meaningfully included in evaluation of CAV after OHT.

Nuclear medicine techniques in transplantation

To evaluate the indications and perspectives of nuclear medicine techniques in transplantation. We performed a systematic review of the literature using PubMed/Medline and Google scholars, with multiple research keywords for each organ accompanying the terms “transplant”, “transplantation”, “graft”, “nuclear imaging”, “scintigraphy”, “PET” and “PET/CT”. The review considers the following organs/systems: kidney, liver, pancreas, heart, lung, bone and salivary glands, as well as a common complication, the post-transplant lymphoproliferative disorder. The references of the retrieved articles were also considered to find supplementary articles. The search was limited to English language. Preoperative workup exploration, preclinical and animal studies were not included in the review. A total of 146 original articles were considered for the review, including 118 retrospective and 28 prospective studies. The functional integrity of the renal graft is safely and reliably assessed using quantitative dynamic scintigraphy with 99mTc-DTPA or 99mTc-MAG3. 18F-FDG PET/CT is a promising method for early detection of acute rejection. The glomerular filtration rate (GFR) of potential donors should ideally be assessed using 51Cr-EDTA, and the split renal function could be quantified using 99mTc-MAG3 or 99mTc-DMSA imaging. In liver transplantation, both 99mTc-GSA and 99mTc-HIDA scintigraphies can be used for evaluating the function of transplanted liver, and 18F-FDG PET/CT increasingly appears as a powerful tool for characterising the aggressiveness of hepatocellular carcinoma and contributes to the decision of transplantation in selected patients. In heart transplants, the major indication is the evaluation of cardiac allograft vasculopathy using myocardial perfusion imaging, either with SPECT or PET. In the context of lung transplantation, perfusion scanning helps select potential donors and contributes to the postoperative follow-up, either early on for detecting primary graft dysfunction or later on in the diagnosis of chronic rejection. Bone scintigraphy and 18F-NaF PET/CT are valuable tools for assessing bone graft viability. This is particularly established in mandible grafts, but convincing data are available in other types of graft. Salivary gland transplantation is not frequently performed, but in such a clinical situation, 99mTcO4 scintigraphy is an elegant way to help select the transplant and to verify the viability of the graft. Finally, 18F-FDG PET/CT is very effective in patients with post-transplant lymphoproliferative disorder (PTLD), both at diagnosis and for evaluating the response to treatment. Nuclear medicine techniques are strongly established as valuable clinical tools in a wide variety of indications, before and after organ transplantation. Furthermore, 18F-FDG PET/CT in PTLD and radio-isotopic evaluation of the renal function in putative kidney donors are recommended in clinical algorithms proposed in international guidelines.

Evaluation of coronary adventitial vasa vasorum using 3D optical coherence tomography – Animal and human studies

ObjectivesThis study sought to evaluate adventitial vasa vasorum (VV) in vivo with novel imaging technique of optical coherence tomography (OCT). MethodsTo verify OCT methods for quantification of VV, we first studied 2 swine carotid arteries in a model of focal angiogenesis by autologous blood injection, and compared microchannel volume (MCV) by OCT and VV by m-CT, and counts of those. In OCT images, adventitial MC was identified as signal-voiding areas which were located within 1 mm from the lumen-intima border. After manually tracing microchannel areas and the boundaries of lumen-intima and media-adventitial in all slices, we reconstructed 3D images. Moreover, we performed with OCT imaging in 8 recipients referred for evaluation of cardiac allograft vasculopathy at 1 year after heart transplantation. MCV and plaque volume (PV) were assessed with 3D images in each 10-mm-segment. ResultsIn the animal study, among the 16 corresponding 1-mm-segments, there were significant correlations of count and volume between both the modalities (count r2 = 0.80, P < 0.01; volume r2 = 0.50, P < 0.01) and a good agreement with a systemic bias toward underestimation with m-CT. In the human study, there was a significant positive correlation between MCV and PV (segment number = 24, r2 = 0.63, P < 0.01). ConclusionOur results suggest that evaluation of MCV with 3D OCT imaging might be a novel method to estimate the amount of adventitial VV in vivo, and further has the potential to provide a pathophysiological insight into a role of the VV in allograft vasculopathy.

Neopterin Predicts Poor Short- and Long-Term Outcomes in Heart Transplant Recipients

Purpose Neopterin (NP), a product of activated macrophages, may be associated with adverse outcomes in patients after heart transplantation (HTx). The study was designed to analyze the association of NP plasma levels in early posttransplant period on short- and long-term outcomes in heart transplant recipients. Methods and Materials 98 heart recipients, 89 men and 9 women, aged 37.4±12.3 years, were followed prospectively for 1-11 years (5.7±3.9) after the operation performed for dilated (61 pts) or ischaemic (37 pts) cardiomyopathy. Immunosuppressive therapy included steroids, cyclosporine A or tacrolimus, and mycophenolate mofetil. The posttransplant variables analyzed included the evaluation of cardiac allograft vasculopathy (CAV), acute cellular (ACR) and antibody-mediated rejection (AMR). Plasma levels of NP were measured by ELISA. Results During follow-up, severe episodes of ACR (14 pts, 14.3%, at 6.5±5.2 months after HTx), AMR (17 pts, 17.34%, at 8.5±10.6 months after HTx), and CAV (16 pts, 16.32%, at 36.5±25.5 months after HTx) occurred in 37 patients (37.7%). NP plasma levels correlated with severity of ACR (11.3±4.3, 47.5±27.8, and 148.6±37.7 nmol/l in recipients with grade “0”, “1R”and “2R” resp., rs=0.86, t=16.5, p Conclusions Early post-transplant macrophage activation, as reflected by NP levels, is highly predictable for the development of ACR and AMR in short-term and is associated with CAV development in long-term period after HTx.

Optical Coherence Tomography and Highly Sensitivity Troponin T for Evaluating Cardiac Allograft Vasculopathy

Cardiac allograft vasculopathy (CAV) is a major impediment to long-term graft survival after heart transplantation. Intravascular ultrasound (IVUS) is more sensitive than coronary angiography for diagnosis, but the identification of specific plaque components or plaque composition is limited. In addition, there is an evident need for other noninvasive tools for diagnosing CAV. The aim of this study was to assess the utility of 2 new techniques for evaluating CAV: optical coherence tomography (OCT), and new high-sensitivity troponin T (hsTnT) assays. In 21 heart transplantation patients, coronary arteriography with IVUS and OCT were performed. Maximal intimal thickness (MIT) and luminal area at the most severe site were measured using the 2 techniques. Immediately before cardiac catheterization, blood samples were obtained and hsTnT levels measured. The evaluation of CAV by OCT showed a good correlation with IVUS measurements, with a mean difference in MIT of 0.0033 (95% confidence interval -0.049 to 0.043), taking advantage of lower interobserver variability (r = 0.94 for OCT vs r = 0.78 for IVUS) and better plaque characterization. When independent predictors of MIT were assessed in a multiple linear regression model, time after transplantation (β = 0.488, p = 0.004) and hsTnT (β = 0.392, p = 0.011) were the only independent predictors of MIT (R(2) = 0.591). In conclusion, this study is the first to evaluate 2 new techniques, OCT and hsTnT, in the challenging setting of CAV. The findings suggest that OCT provides lower interobserver variability and better plaque characterization than IVUS. Also, hsTnT could become a useful tool for ruling out CAV.

Angiographic assessment of cardiac allograft vasculopathy: results of a Consensus Conference of the Task Force for Thoracic Organ Transplantation of the German Cardiac Society

Angiograms of cardiac transplant (HTx) recipients were to be evaluated in a ring experiment and a joint consensus on criteria of angiographic evaluation of coronary arteries of HTx patients was to be reached. Twenty-four coronary angiograms from 11 hospitals were circulated. One hundred eighty-eight blinded evaluations were returned. A joint evaluation by six experienced cardiologists was used as reference standard and a consensus evaluation form was developed. Significant lesions (stenosis 75%, 50% in the left main coronary artery) were diagnosed in 10/23 abnormal coronary angiograms (41.7%). Interventional revascularization was recommended in 8/10 (80%). In 21 coronary angiograms distal pruning was found and in 11/21 (52.4%) cases with distal pruning occlusion of at least one peripheral vessel was detected. The best kappa value (0.7) was found for the presence of at least one clinically significant stenosis. Agreement on the site and grade of local stenosis was much less. Some agreement on remodeling was found in assessing diffuse narrowing in the LCA (kappa=0.371, P<0.001). The kappa value for peripheral obliteration was 0.331 (P=0.001). Angiographic evaluation of cardiac allograft vasculopathy, particularly of diffuse and peripheral disease and remodeling, needs standardization. This should be performed in a downward compatible improvement process.

Evaluation of Cardiac Allograft Vasculopathy by Multidetector Computed Tomography and Whole-Heart Magnetic Resonance Coronary Angiography

Cardiac allograft vasculopathy (CAV) is a major complication that limits the long-term survival of recipients of heart transplants. In the present study the feasibility of 2 noninvasive approaches for detecting CAV (multidetector computed tomography (MDCT) and whole-heart magnetic resonance coronary angiography (MRCA)) was compared with conventional coronary angiography (CCAG). Of 22 heart transplant recipients who underwent CCAG screening, 13 had only MDCT, 16 had only MRCA, and 7 had both noninvasive modalities. The coronary arterial tree was divided into 9 segments. Detection of vasculopathy by coronary segments was compared between 16-/64-detector computed tomography (CT) or MRCA and CCAG. The sensitivity of both 16- and 64-detector CT for diagnosing CAV was 69.6%, and specificity was 96.8%. The sensitivity and specificity by 64-detector CT alone were 90.0% and 97.5%, respectively; its positive and negative predictive values were 81.8% and 98.7% respectively. For MRCA, sensitivity was 60%, specificity, 100%, positive predictive value, 100% and negative predictive value, 92.2%. MRCA showed no false positives. MDCT, especially 64-detector CT, is feasible for detecting CAV, whereas MRCA currently shows limited sensitivity.

103: Evaluation of Cardiac Allograft Vasculopathy by Multi-Detector CT and Whole-Heart MR Coronary Angiography

103: Evaluation of Cardiac Allograft Vasculopathy by Multi-Detector CT and Whole-Heart MR Coronary Angiography