Aortic Dissection in Takayasu Arteritis

Takayasu's arteritis and acute type B aortic dissection treated with a stent graft

OBJECTIVES

Takayasu's arteritis is a large vessel vasculitis which usually involves the aorta and its first generation branches. Aortic dissection, however, is a rare manifestation of Takayasu's arteritis and for this reason optimum management in both short and long term is unknown.

METHODS

This is a case of a 31-year-old female presenting with acute type B AD in association with underlying TA which failed to respond to conservative management and underwent thoracic stent grafting (TEVAR).

RESULTS

Despite successful coverage of the intimal breach in the thoracic aorta by TEVAR there were complications with delivery of the stent which required a conduit sutured to the right common iliac artery. Also post-TEVAR computed tomography showed a localised dissection of the origin of the left common carotid artery which may have been iatrogenic possibly due to the stiff guidewire used during delivery of the stent graft to the thoracic aorta.

CONCLUSIONS

The use of TEVAR for an acute type B AD in those with TA may be problematic. The fragility of the major arteries increases the likelihood of iatrogenic periprocedural complications and long-term surveillance is essential due to significant chance of further arterial complications in type B AD occurring in TA.

Chronic dissection of the abdominal aorta as a rare complication of Takayasu disease

Takayasu's arteritis exposes to complications of varying severity, such as arterial stenosis, thrombosis, and more rarely aneurysms. Aortic dissection is a rare complication of Takayasu's disease, reported in few times in the literature, only 7 of which concern the abdominal aorta. We report the case of a 41-year-old woman followed for Takayasu disease for 15 years, who presented an asymptomatic and chronic dissection of the abdominal subrenal aorta. The patient underwent conservative medical treatment. After a follow-up of 17 months, the aortic dissection was still asymptomatic, with a stable appearance on follow-up imaging. To our knowledge, this is the first case report of asymptomatic aortic dissection as a rare complication of Takayasu disease.

99-Case Study of Sporadic Aortic Dissection by Whole Exome Sequencing Indicated Novel Disease-Associated Genes and Variants in Chinese Population

Background

In this study, the whole exome sequencing in human aortic dissection, a highly lethal cardiovascular disease, was investigated to explore the aortic dissection-associated genes and variants in Chinese population.

Methods

Whole exome sequencing was performed in 99 cases of aortic dissection. All single nucleotide polymorphisms (SNPs), insertions/deletions (InDels), and copy number variations (CNVs) were filtered to exclude the benign variants. Enrichment analysis and disease-gene correlation analysis were performed.

Results

3425873 SNPs, 685245 InDels, and 1177 CNVs were identified, and aortic dissection-associated SNPs, InDels, and CNVs were collected. After the disease correlation analysis, 20 candidate genes were identified. Part of these genes such as MYH11, FBN1, and ACTA2 were consistent with previous studies, while MLX, DAB2IP, EP300, ZFYVE9, PML, and PRKCD were newly identified as candidate aortic dissection-associated genes.

Conclusion

The pathogenic and likely pathogenic variants in most of AD-associated genes (FBN1, MYH11, EFEMP2, TGFBR2, FBN2, COL3A1, and MYLK) were identified in our cohort study, and pathogenic CNVs involved in MYH11, COL family, and FBN were also identified which are not detectable by other NGS analysis. The correlation between MLX, DAB2IP, EP300, ZFYVE9, PML, PRKCD, and aortic dissection was identified, and EP300 may play a key role in AD.

Intervention in Takayasu Aortitis: When, Where and How?

Takayasu arteritis is a large vessel vasculitis which commonly affects the aorta and its major branches. Active arterial inflammation is characterised by the presence of T and B lymphocytes, natural killer cells, macrophages and occasional multinucleate giant cells. Uncontrolled vascular inflammation can progress to cause arterial stenosis, occlusion or aneurysmal dilatation. Medical treatment involves combination immunosuppression and more recently biologic therapies targeting TNF-α and IL-6. Due to the typical delays in diagnosis and accumulation of arterial injury, open and endovascular surgical intervention are important and potentially life-saving treatment options for Takayasu arteritis. Common indications for surgery include aortic coarctation and ascending aortic dilatation ± aortic valve regurgitation, renal artery stenosis, ischaemic heart disease, supra-aortic disease, mesenteric ischaemia, severe limb-threatening claudication and aneurysm repair. Surgical outcomes are markedly improved in patients with clinically inactive disease and those who receive adequate periprocedural immunosuppression. Decisions regarding surgical approaches are best made as part of a multi-disciplinary team.

Aortic dilatation in patients with large vessel vasculitis: A longitudinal case control study using PET/CT

OBJECTIVE

To evaluate aortic diameter and predictors of aortic dilatation using ¹⁸FDG-PET/CT in a longitudinally followed cohort of patients with large vessel vasculitis (LVV) compared with controls.

METHODS

All consecutive patients with LVV who underwent at least 2 PET/CT scans between January 2008 and May 2015 were included. The first and last PET/CT study was evaluated by a radiologist and a nuclear medicine physician. Diameter and FDG uptake of the aorta was measured at 4 different levels: ascending, descending thoracic, suprarenal and infrarenal abdominal aorta. Twenty-nine age- and sex-matched patients with lymphoma who underwent at least 2 PET/CT scans in the same time interval were selected as controls.

RESULTS

93 patients with LVV were included in the study. In the time interval between first and last PET/CT study (median time 31 months), the diameter of the ascending, descending thoracic and suprarenal abdominal aorta significantly increased in LVV patients but not in controls. At last PET/CT, patients with LVV compared with controls had higher diameter of ascending [35.41 (5.54) vs 32.97 (4.11) mm, p = 0.029], descending thoracic [28.42 (4.82) vs 25.72 (3.55) mm, p = 0.007] and suprarenal abdominal aorta, mean [25.34 (7.01) vs 22.16 (3.26) mm, p = 0.005] and more frequently had aortic dilatation [19% vs 3%, p = 0.023]. Significant predictors of aortic dilatation were male sex [OR 7.27, p = 0.001] and, only for GCA, hypertension [OR 6.30, p = 0.031]. Finally, GCA patients with aortic FDG uptake grade 3 at first PET/CT, compared to those with aortic FDG uptake ≤2, had significantly higher aortic diameter.

CONCLUSIONS

Patients with LVV are at increased risk of aortic dilatation compared with age- and sex-matched controls. Significant predictors of aortic dilatation are male sex and, only for GCA, hypertension. GCA patients with aortic FDG uptake grade 3 are at increased risk of aortic dilatation.