Endovascular treatment for thoracic aortic disease from the Global Registry for Endovascular Aortic Treatment

OBJECTIVE

Global Registry for Endovascular Aortic Treatment (GREAT) is an international prospective multicenter registry collecting real-world data on performance of W. L. Gore thoracic and abdominal aortic endografts. This analysis evaluated the long-term differences in patient survival and device performance in patients undergoing thoracic endovascular aortic repair (TEVAR) for any thoracic aortic pathology.

METHODS

From August 2010 to October 2016, 5014 patients were enrolled in GREAT. The population of interest was comprised of only patients treated for thoracic aortic pathologies. Through 5 years, primary outcomes were all-cause and aortic-related mortality, stroke, aortic rupture, endoleaks, migration, fracture, compression, paraplegia, and any reintervention through 5 years, grouped by pathology. Secondary outcomes were reintervention rate and freedom from serious device- and aortic-related events.

RESULTS

The 578 patients with thoracic aortic pathologies enrolled in GREAT and identified for this analysis were categorized by common pathologies: thoracic aneurysm (n = 239), thoracic dissection (n = 203), arch (n = 26), and other (n = 110). The mean age of this population was 66.1 ± 12.8 years, and 64.7% were male. Procedure survival was 99.7%. In the overall group, at index procedure to 30 days and 31 days to 5 years, Kaplan-Meier estimates of freedom from all-cause mortality were 99.6% and 66.4%, respectively, and for aortic-related mortality were 97.7% and 94.6%, respectively. Aortic rupture rate was 0.5% (n = 3) at 30 days and 1.4% (n = 8) through 5 years. Stroke and spinal cord ischemic events were 1.9% (n = 11) and 1.6% (n = 9) at 30 days and at 5 years were 3.6% (n = 20), 0.5% (n = 3), respectively. Reinterventions were required in 7.3% (n = 42) at 30 days and 12.4% (n = 69) through 5 years. The number of patients with endoleaks at 30 days was 2.1% (n = 12): n = 3 (1.1%) for each of types IA, 1B, and II; n = 2 (0.3%) for type III; and n = 4 (0.7%) for unspecified. Through 5 years, the percentage of patients was 8.3% (n = 40): n = 15 (3.1%) for type IA; n = 10 (2.1%) for type IB; n = 11 (2.3%) for type II; and n = 9 (1.9%) for unspecified. One patient (0.2%) had stent migration at 30 days (aneurysm group); none were reported through 5 years. There were no incidents of stent compression or fracture from index procedure through 5 years.

CONCLUSIONS

Data herein demonstrates durability and support for treatment of thoracic aortic disease with the GORE TAG conformable thoracic stent graft, including no incidents of stent compression/fracture and high freedom from aortic-related mortality. The planned analysis of follow-up to 10 years in GREAT will be beneficial.

An early evaluation of the HISTO SPOT® AB ID Class I & II test in cardiothoracic transplant patients

The HISTO SPOT^® AB ID assay (BAG Diagnostics GmbH) is a novel single antigen HLA Class I & II antibody definition test used with the MR.SPOT^® processor. We compared this assay with Luminex^® -based assays to assess its potential application in defining unacceptable antigens for transplantation in patients awaiting transplants with cardiothoracic organs. A cohort of 40 sensitized cardiothoracic patients were identified, and one sample was selected from each patient. The required screening was based on the patients' antibody profiles (Class I, n = 17, Class II, n = 11, Class I & II, n = 12). Samples were screened with LABScreen™ Single Antigen (SAg), LIFECODES^® LSA™, HISTO SPOT^® AB ID, and an acid modified LABScreen™ SAg test for detecting antibodies against denatured HLA. Results indicated that HISTO SPOT^® AB ID had reduced sensitivity (68% for Class I; 69% for Class II). When compared to LABScreen™ and LIFECODES^® , HISTO SPOT^® AB ID failed to detect Luminex^® -defined antibodies with median fluorescence intensity (MFI) ranging from 1114 to 24,489. The HISTO SPOT^® AB ID panel used in the study had reduced antigen representation compared with Luminex^® -based assays which further compromised its capacity for antibody detection and definition. Further work is needed to evaluate the clinical relevance of these differences between the performance of HISTO SPOT^® and Luminex^® -based methods.

Targeting the arginine metabolic brake enhances immunotherapy for leukaemia

Therapeutic approaches which aim to target Acute Myeloid Leukaemia through enhancement of patients' immune responses have demonstrated limited efficacy to date, despite encouraging preclinical data. Examination of AML patients treated with azacitidine (AZA) and vorinostat (VOR) in a Phase II trial, demonstrated an increase in the expression of Cancer-Testis Antigens (MAGE, RAGE, LAGE, SSX2 and TRAG3) on blasts and that these can be recognised by circulating antigen-specific T cells. Although the T cells have the potential to be activated by these unmasked antigens, the low arginine microenvironment created by AML blast Arginase II activity acts a metabolic brake leading to T cell exhaustion. T cells exhibit impaired proliferation, reduced IFN-γ release and PD-1 up-regulation in response to antigen stimulation under low arginine conditions. Inhibition of arginine metabolism enhanced the proliferation and cytotoxicity of anti-NY-ESO T cells against AZA/VOR treated AML blasts, and can boost anti-CD33 Chimeric Antigen Receptor-T cell cytotoxicity. Therefore, measurement of plasma arginine concentrations in combination with therapeutic targeting of arginase activity in AML blasts could be a key adjunct to immunotherapy.