Detection of aortic wall instability with the new dissectometer: Correlation with histological findings

Although risk stratification for aortic dissection or rupture based on aortic diameter is quite suboptimal, alternative methods for the assessment of the aortic wall stability are rare. We assessed the mechanical properties of the aortic wall by a new custom-made device mimicking transversal aortic wall shear stress during open heart surgery in comparison with histological examination.

One-hundred and five aortic walls were tested by the 'dissectometer' (seven different measured and two calculated values) as well as histological examination was performed.

Histological examination classified the aortic wall as normal in 54 (51.4%) patients and pathologic in 51 (48.6%) patients. Six out of nine parameters assessed by the dissectometer showed a significant correlation to histological findings. Using ROC-analysis, the most reliable parameter (P9) showed a sensitivity of 93.3% and a specificity of 80.4% with an area under the curve of 0.89 when using a cut-off value of 3.4. In the logistic regression analysis, P9 was an independent predictor for aortic wall instability (OR 28.983, 95% CI 11.507-72.993, p < 0.0001).

The dissectometer is suitable for discriminating between stable and unstable aortic walls with a good correlation to histological examination holding promise for direct and quick intraoperative identification of aortic walls at risk for dissection.