Appropriate sizing of the frozen elephant trunk: How to predict proximal descending aortic diameter prior to dissection?

OBJECTIVE: The predissection aortic diameter is the best reference for determining the size of the frozen elephant trunk in aortic dissection. We aimed to develop a new prediction method to estimate the predissection diameter of proximal descending aorta. Furthermore, we evaluated the accuracy of the estimated predissection proximal descending aortic diameters calculated using 3 prediction methods. METHODS: A total of 39 patients with acute type A aortic dissection who underwent predissection computed tomography were included in derivation sets. We measured the aortic dimensions at 3 levels of the proximal descending aorta: 5, 10, and 15 cm from zone 2. We developed a new prediction method-postdissection aortic diameter divided by 1.13 (AoDNew factor)-and estimated the predissection aortic diameter using the new and previously proposed methods by Rylski (AoDRylski) and Yamauchi (EquationYamauchi). Furthermore, we validated the new prediction method using a validation dataset with 24 patients. RESULTS: The rate of bias ≤2 mm was significantly greater with EquationYamauchi and AoDNew factor than with AoDRylski in the derivation group at each level of the proximal descending aorta (P < .001). In the validation group, the rate of bias ≤2 mm was significantly greater with EquationYamauchi and AoDNew factor than with AoDRylski at 10 cm and 15 cm from zone 2 (10 cm: P = .014, 15 cm: P < .001). CONCLUSIONS: These results suggest that the new prediction method can be used as a simple and accurate estimation method for the predissection aortic diameter at the proximal descending aorta.

[Non-A Non-B Aortic Dissection Complicated with Right Aortic Arch Treated by Extended Thoracic Aortic Repair].

A 44-year old man with a history of Stanford type B acute aortic dissection was admitted for the treatment of acute aortic dissection. Computed tomography( CT) scan showed a descending entry-type non-A non-B aortic dissection with a maximum diameter of 65 mm occurring in a patient with Edwards typeⅢ right aortic arch whose left subclavian artery was obliterated. The patient was initially treated conservatively and underwent one-stage extended aortic repair from the ascending aorta to the descending thoracic aorta via median sternotomy 22 days after the symptom onset. Although the patient suffered from right empyema postoperatively, he was discharged from the hospital on postoperative day 64 after 4 weeks antibiotics therapy. The patient was also complicated by right recurrent nerve palsy, hoarseness improved over the 8 months after surgery.

Perioperative factors associated with aneurysm sac size changes after endovascular aneurysm repair.

PURPOSE: To identify the perioperative factors associated with aneurysm size changes after endovascular aortic aneurysm repair (EVAR). METHODS: Between August, 2008 and December, 2014, 187 patients underwent EVAR treatment in our institution. The subjects of this study were 135 of these patients without peripheral artery disease, who were followed up with computed tomography (CT) for 3 years. Significant aneurysm size change was defined as sac size change of more than 5 mm from the baseline. RESULTS: Sac enlargement was identified in 25 patients (18.5%) and sac shrinkage was identified in 59 (43.7%) patients. The factors associated with sac enlargement were postoperative pulse wave velocity (OR: odds ratio 3.80, p = 0.047), prevalence of a type 2 endoleak 1 week after surgery (OR 4.26, p = 0.022), inner diameter (OR 1.10, p = 0.005), and distance from the lower renal artery to the terminal aorta (OR 1.05, p = 0.017). The factors associated with sac shrinkage were prevalence of a type 2 endoleak (OR 0.09, p < 0.001) and preoperative pulse wave velocity (OR 0.32, p = 0.022). The factors independently associated with type 2 endoleak were the use of an Excluder device (OR 3.99, p = 0.002) and the length of the aneurysm (OR 1.02, p = 0.027). CONCLUSION: Inner diameter, treatment length, perioperative pulse wave velocity, and type 2 endoleak were associated with sac size changes after EVAR.