BIOMECHANICAL RUPTURE RISK ASSESSMENT IN MANAGEMENT OF PATIENTS WITH ABDOMINAL AORTIC ANEURYSM IN COVID-19 PANDEMIC

Background:
The acute phase of the COVID-19 pandemic requires a redefinition of healthcare system to increase the number of available intensive care units for COVID-19 patients. This leads to the postponing of elective surgeries including the treatment of abdominal aortic aneurysm (AAA). The probabilistic rupture risk index (PRRI) recently showed in another experimental project its advantage over the diameter criterion in AAA rupture risk assessment. Its major improvement is in increased specificity and yet has the same sensitivity as the maximal diameter criterion. The objective of this study was to test the clinical applicability of the PRRI method in a quasi-prospective patient cohort study.
Methods:
Nineteen patients (14 males, 5 females) with intact AAA who were postponed due to COVID-19 pandemic were included in this study. The PRRI was calculated at the baseline via Finite Element Method models. If a case was diagnosed as high risk (PRRI>3%), patient was offered priority in AAA intervention. Cases were followed until September 10th 2021 and a number of false positive and false negative cases were recorded.
Results:
Each case was assessed within 3 days. Priority in intervention was offered to two patients with high PRRI. There were 4 false positive (higher PRRI value without consequent AAA rupture) cases and no false negative (low PRRI value with consequent AAA rupture) cases classified by PRRI. In three cases, the follow up was too short to make any conclusion.
Conclusion:
Integrating PRRI into clinical workflow is technically ang logistically possible. Longitudinal validation of PRRI showed auspicious results and it may lead to more precise diagnostic evaluation in comparison to maximal diameter criterion and subsequent personalization of therapeutic approach to patients with AAA.