Aortic arch type, a novel morphological indicator and the risk for acute type B aortic dissection

Area of Science:

• Cardiovascular Imaging
• Medical Morphology
• Aortic Pathology

Background:

• Aortic arch type is a simple morphological feature.
• Its prognostic value for acute type B aortic dissection (aTBAD) is under investigation.
• Comparison with complex aortic measurements is needed.

Purpose of the Study:

• To evaluate aortic arch type as a predictive parameter for aTBAD.
• To compare its prognostic value against aortic length, angulation, and tortuosity index.
• To determine if aortic arch type can serve as an alternative morphological parameter.

Main Methods:

• Propensity score matching was used to create comparable groups of aTBAD patients and controls.
• Three-dimensional aortic models were analyzed for morphological data including diameter, length, angulation, and tortuosity.
• Aortic arch type was classified based on the vertical distance from the brachiocephalic trunk origin to the arch's apex.
• Binary logistic regression and ROC curve analysis were employed.

Main Results:

• Patients with aTBAD exhibited significantly greater aortic diameters, lengths, angulations, and tortuosity indices compared to controls.
• Type III aortic arch was significantly more prevalent in the aTBAD group (P < 0.001).
• Models incorporating mid-aortic arch diameter, ascending aorta length, aortic arch angulation, and tortuosity index showed an AUC of 0.887.
• A model with mid-aortic arch diameter and aortic arch type achieved an AUC of 0.874, with no significant difference in prognostic value compared to the more complex model (P = 0.716).

Conclusions:

• Type III aortic arch, characterized by elongation, increased angulation, and tortuosity, is a significant predictor of aTBAD.
• Aortic arch type serves as a comparable and alternative morphological identifier for high-risk aTBAD patients.
• This simple morphological assessment can aid in risk stratification for aTBAD.