2 DISCUSSION
Outcomes of aortic repair for ATAAD have improved. According to a
Japanese Association for Thoracic Surgery annual report, overall
in-hospital mortality of patients who underwent aortic repair for ATAAD
in 2015 was 9.6% (468/4875).4 Organ malperfusion
associated with ATAAD remains a surgical challenge; patient-specific
approaches are required. Shiiya et al. reported that sole central aortic
repair failed to revascularize the abdominal organ(s) in 5 of 6 patients
with aortic branch dissection.5 Uchida et al. reported
favorable outcomes of a surgical strategy that prioritizes peripheral
revascularization in patients with organ
malperfusion.6 If a patient shows stable hemodynamics
and branch-type malperfusion, early revascularization seems to be a
feasible approach. Our patient’s ATAAD was complicated by severe
mesenteric malperfusion resulting from occlusion of both the celiac
artery and SMA. We think that sole central aortic repair or delayed SMA
revascularization could have resulted in irreversible mesenteric
ischemia.
Previously, we reported ATAAD complicated by malperfusion of at least
one organ in 30.9% (308/1029) of patients and that we found obesity
(body mass index >30 kg/m2), preoperative
shock (systolic blood pressure <80 mmHg), and mesenteric
malperfusion to be independent predictors of-in-hospital death for those
with such malperfusion.7 Treatment of the
ATAAD-induced cardiac tamponade is of paramount importance in patients
undergoing immediate aortic repair; however, the optimal management
technique remains controversial. Lin et al. reported similar outcomes
between emergency subxiphoid pericardiotomy and emergency establishment
of CPB.8 Pericardiotomy performed initially for
hematoma removal poses a risk of continuous bleeding in cases of aortic
rupture. Our case was complicated by cardiac tamponade leading to
hemodynamic instability, but aortic rupture had not occurred. In cases
of aortic rupture, CPB must be established promptly, before the aortic
repair. Revascularization of abdominal organs would be the second
priority in such cases.
In conclusion, in our case of ATAAD complicated by cardiac tamponade and
severe mesenteric malperfusion, initial release of pericardial hematoma
and revascularization of the SMA prevented further mesenteric ischemia
and paved the way for aortic repair.