The 301 Classification: A Proposed Modification to the Stanford Type B Aortic Dissection Classification for Thoracic Endovascular Aortic Repair Prognostication.

OBJECTIVE: To assess the usefulness of a modified Stanford classification for risk stratification of complications after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD). PATIENTS AND METHODS: This retrospective analysis included 201 patients from an observational multicenter cohort study who underwent TEVAR for TBAD from January 1, 2011, to December 31, 2016. The patients were divided by using a modified Stanford classification, termed 301, into 3 groups: types B1 (n=62) and B3 (n=24), with a true and false lumen, respectively, descending closely along the thoracic vertebral bodies, and type B2 (n=115), a semi-spiral or spiral configuration. The value of the 301 classification in assessing the risk for post-TEVAR thoracic aortic expansion, as main outcome, and other complications was assessed by using the Kaplan-Meier method and multivariable Cox proportional hazards models. RESULTS: Median follow-up duration was 26.37 months, and the 24-month cumulative rate of freedom from thoracic aortic enlargement was 0.58 (95% CI, 0.25 to 0.81) for type B3, 0.75 (95% CI, 0.64 to 0.83) for type B2, and 0.97 (95% CI, 0.88 to 0.99) for type B1. In the multivariable Cox regression models, types B2 and B3 with type B1 as reference were independently associated with the risk for thoracic aortic expansion (type B2: hazard ratio, 7.81; 95% CI, 1.84 to 33.13; type B3: hazard ratio, 13.91; 95% CI, 2.86 to 67.69). CONCLUSION: The 301 classification, a modified Stanford classification system in the era of endovascular repair, appears to improve the risk stratification of patients with TBAD undergoing TEVAR. TRIAL REGISTRATION: Chinese Clinical Trial Registry number: ChiCTR-POC-17011726.

Dimethyl sulfoxide could be a useful probe to evaluate unusual skin angioneurotic reaction and epidermal permeability.

BACKGROUND/OBJECTIVES: Dimethyl sulfoxide (DMSO) has been suggested as a traditional chemical probe for assessing skin susceptibility and barrier function. The purpose of this study was to determine the role of DMSO test for the evaluation of unusual skin angioneurotic reaction and epidermal permeability. METHODS: Thirty healthy volunteers were exposed to 98% DMSO on the flexor forearm skin for three exposure durations (5 min, 10 min and 15 min). Clinical visual score and biological physical parameters were obtained. The volunteers were divided into two groups according to the clinical visual scoring. The skin parameters were subsequently analyzed. RESULTS: There was a significant correlation between clinical visual score and biological physical parameters. The skin color parameters (a*, oxyhemoglobin, erythema and melanin index) and blood flow values were significant between two groups regardless of duration of DMSO exposure, and a significant difference between density values could also be detected if we regrouped the volunteers according to the sting-producing score. Our results also suggested there was no correlation between questionnaire score and clinical visual score or other parameters. CONCLUSIONS: Application of 98% DMSO for 10 min combined with a* (at 30 min) and blood flow (at 10 min) values could help us to identify persons with a hyper-angionerotic reaction to chemical stimulus. The penetrative activity of DMSO correlated with the thickness of the individual's skin.