The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Jun 2016
Extracellular matrix fiber microarchitecture is region-specific in bicuspid aortic valve-associated ascending aortopathy.
Ascending thoracic aortic aneurysm (ATAA) in patients with bicuspid aortic valve (BAV) commonly dilate asymmetrically compared with patients with tricuspid aortic valve (TAV). This discrepancy in aneurysm geometry led us to hypothesize that microarchitectural differences underlie the observed asymmetric dilatation pattern. The purpose of this study was to characterize the microarchitectural distinctions of the extracellular matrix of the 2 phenotypes with a focus on the proportion of radially oriented elastin and collagen fibers in different circumferential aortic regions. ⋯ The differential pattern of fiber orientation noted between L and N-R regions help explain the unique pattern of greater curvature dilatation of BAV-ATAA. The distinctions noted in matrix microarchitecture may form the basis of differing aneurysm geometries and aortic wall integrities in ATAAs arising in these different valve morphologies.
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J. Thorac. Cardiovasc. Surg. · Jun 2016
EditorialPropensity-score analysis in thoracic surgery: When, why, and an introduction to how.
Propensity score matching is a valuable tool for dealing with observational data and nonrandom treatment assignment, which often results in groups that differ systematically in numerous measured and unmeasured variables. When these systematically different variables are associated with both group assignment and the outcome(s) of interest, bias is introduced. Propensity score matching assigns a propensity for group assignment, which is then used to create 2 groups that are balanced across all possible variables that might influence exposure assignment. When used in the proper conditions, these analytics allow for more accurate and precise estimates of risk for a variety of outcomes.