Total Aortic Repair for Acute Type A Aortic Dissection Complicated by Malperfusion or Symptomatic Branch Vessel Malalignment

Effect of nadir hematocrit during cardiopulmonary bypass on the early outcomes after surgical repair of acute type A aortic dissection

OBJECTIVE

Although hemodilution during hypothermic cardiopulmonary bypass (CPB) had been thought to improve microcirculation and reduce blood viscosity, there has been no report investigating the effect of low nadir hematocrit (Hct) values caused by severe hemodilution on the surgical outcomes of patients with acute type A aortic dissection (ATAAD).

METHODS

We retrospectively reviewed 112 consecutive patients who emergently underwent emergency surgical repair of ATAAD at our institution. The patients were classified into the high Hct (nadir Hct ≥ 21% during CPB; n = 51) and low Hct (nadir Hct < 21% during CPB; n = 61) groups. After propensity score matching of preoperative characteristics, surgical outcomes were compared between the groups.

RESULTS

Although there was no difference in the surgical procedure, longer CPB time and more blood transfusion during surgery were needed in the low Hct group than in the high Hct group. After surgery, estimated glomerular filtration rate was significantly lower (p = .015), lactaic acid was higher (p = .045), and intubation time was longer (p = .018) in the low Hct group than in the high Hct group, although there was no difference in hospital mortality between the groups. The AUC of the nadir Hct during CPB as a prognostic indicator of prolonged postoperative ventilator support was 0.8, with the highest accuracy at 16.7% (sensitivity 88%, specificity 76.9%). In all cohorts, female sex was an independent risk factor for a lower nadir Hct value of <21% during CPB.

CONCLUSION

A lower nadir Hct value of <21% during CPB may be associated with postoperative renal dysfunction and prolonged ventilator support in patients with ATAAD.

Role of hybrid arch debranching in the treatment of newly diagnosed aortic arch malperfusion after repair of acute type A aortic dissection

We present the case of a 41-year-old man who underwent repair of an acute DeBakey type A aortic dissection with a Bentall-De Bono operation and presented with an early aortic arch malperfusion. The malperfusion was successfully treated with a hybrid arch debranching procedure. In this setting, the hybrid arch debranching procedure offers a safe alternative for repair.

Surgical management of acute type A aortic dissection: branch-first arch replacement with total aortic repair

Acute type A dissection (ATAAD) remains a morbid condition with reported surgical mortality as high as 25%. We describe our surgical approach to ATAAD and discuss the indications for adjunct techniques such as the frozen elephant trunk or complete aortic repair with endovascular methods. Arch replacement using the "branch-first technique" allows for complete root, ascending aorta, and arch replacement. A long landing zone is created for proximal endografting with a covered stent. Balloon-assisted intimal disruption and bare metal stenting of all residual dissected aorta to the level of the aortic bifurcation is then performed to obliterate the false lumen (FL) and achieve single true lumen (TL) flow. Additional branch vessel stenting is performed as required.