The early results of TEVAR for non-acute Stanford type B aortic dissection were favourable. However, for cases with patent false lumens, complete obliteration of the false lumen of the entire aorta was difficult to achieve. Absence of the primary entry at the outer curvature of the distal aortic arch, younger age, small aortic diameter and absence of the abdominal aortic branches arising from the false lumen were the key success factors.

OBJECTIVES In this study, we investigated the early and midterm outcomes of initial watch-and-wait strategy for Stanford type A intramural haematoma and acute aortic dissection with thrombosed false lumen of the ascending aorta in patients with a maximum aortic diameter of ≤50 mm, pain score of ≤3/10 and no ulcer-like projection in the ascending aorta. METHODS Inpatient and outpatient records were retrospectively reviewed. RESULTS Of the 81 patients with type A intramural haematoma and acute aortic dissection with the thrombosed false lumen of the ascending aorta between April 2011 and April 2019, a watch-and-wait strategy was selected in 46 patients. The mean age of the patients was 68 years, and 22 (48%) patients were female. Ten patients underwent emergency pericardial drainage for cardiac tamponade at the time of presentation and 8 patients underwent aortic repair during hospitalization for new ulcer-like projection, re-dissection or rupture. In-hospital mortality occurred in 2 (4%) patients. During follow-up, survival at 1 and 2 years was 95% and 92%, respectively. There was no significant difference in survival or aortic events between patients in whom the watch-and-wait strategy and emergency surgical treatment were indicated. CONCLUSIONS The early and midterm outcomes of the initial watch-and-wait strategy were favourable for type A intramural haematoma and acute aortic dissection with the thrombosed false lumen of the ascending aorta in Japanese patients with a maximum aortic diameter of ≤50 mm, pain score of ≤3/10 and no ulcer-like projection. Further study is required to show the safety of this strategy.

The primary entry at the outer curvature of the distal aortic arch, as well as the large aortic diameter, is associated with a higher risk of late open aortic surgery, aortic intervention and aortic events in acute type B aortic dissection. Thus, the entry site should be taken into consideration in the establishment of an appropriate treatment indication of type B aortic dissection.

However, in some cases of distal DVT there is extension to the proximal vein, and so anticoagulation therapy is still performed for all DVT patients in many institutes, a practice that is believed to be related to an insufficiency of evidence regarding the optimal treatment method for distal DVT, including indications for anticoagulation therapy. A flowchart of the medical treatment method for venous thrombosis is described in the medical safety handbook of Kitasato University Hospital, and most patients who develop DVT in hospital have a consultation in the Department of Cardiovascular Surgery. In accordance with the guidelines, anticoagulation therapy is not the firstline treatment for patients with distal DVT; the patients are re-evaluated using ultrasonography 2 weeks and 3 months after their first visit. Anticoagulation therapy is only initiated for patients who showed DVT exacerbation. Therefore, the present study aimed to retrospectively investigate the treatment results of patients with distal DVT to clarify the risk factors for extension to the proximal vein and indications for anticoagulation therapy.

A folded elephant trunk in a small-calibre lumen can cause haemolysis. Therefore, inserting an elephant trunk in a small-calibre true lumen during surgery for chronic aortic dissection should be avoided.