International Expert Consensus on the Management of Acute Aortic Type B Intramural Haematoma and Penetrating Ulcer.

Objective The aim of this study was to achieve an international expert consensus on managing acute type B penetrating aortic ulcers (PAUs) and intramural haematomas (IMHs). Methods A modified Delphi consensus process was employed to develop recommendations for the management of acute type B PAU and IMH. Surveys were sent to international experts practicing in high volume aortic centres worldwide. Statements were voted on using a four point Likert scale in a three round Delphi process. Statements achieving grade A (full agreement 75%) or B (overall agreement 80%, full disagreement < 5%) were included as expert recommendations. Consistency of responses was measured using Cohen's κ and the intraclass correlation coefficient. Results Eighty three experts were included in the final analysis: 25 statements achieved a consensus, 18 (72%) receiving a grade B strength and 7 (28%) a grade A strength. Most statements (97%) had a high consistency classified as grade I or II. The expert panel agreed on the indication for thoracic endovascular aortic repair (TEVAR) for complicated IMH/PAU, defined by rupture or refractory pain/hypertension. Uncomplicated IMH/PAU should be managed conservatively and followed up with serial computed tomography imaging during the acute phase. High risk uncomplicated IMHs are identified by increased haematoma thickness, new onset or increased size of ulcer like projections, or transition to aortic dissection; high risk uncomplicated PAUs are defined by new associated haematoma, PAU width/depth increase, or total aortic diameter increase. Uncomplicated high risk IMH/PAUs may be considered for TEVAR. In performing TEVAR, a proximal sealing length > 20 mm in a site free from haematoma should be achieved, eventually extending in zone 2, with a 0 - 10% oversize. Patency of the left subclavian artery should be maintained. Conclusion An agreement among international experts was achieved on assessment, management, and follow up of acute type B IMHs and PAUs, addressing areas of inconsistencies or knowledge gaps in existing guidelines.