Aortic Dissection Repair

(PDF) Surgical repair of aortic dissection 16 years post-Ross procedure

Aortic Dissection Repair | Johns Hopkins Medicine

aneurysmal degeneration and planning for elective aneurysm

repair had been underway. Given the patient’s symptomatic

presentation and associated CT findings, she was admitted for

medical optimization and was taken to the operating room

8 days later.

Intraoperatively, transesophageal echocardiography revealed

severe aortic regurgitation with dilatation of the autograft root

to 6.4 cm. On gross examination, degeneration of the aortic

valve leaflets and limited dissection of the non-coronary sinus

of the autograft was appreciated (Fig. 2). After the autograft and

valve were excised and the coronary artery buttons mobilized, a

29-mm bioprosthesis and Valsalva graft were sutured to the

annulus of the autograft. The coronary buttons were anasto-

mosed to the graft, and finally the graft was anastomosed to the

distal ascending aorta. After routine de-airing maneuvers, the

aortic cross-clamp was released, and immediately the patient

experienced severe left ventricular (LV) dysfunction and hemo-

dynamic instability. Accordingly, the heart was rearrested and

the Valsalva graft was opened to inspect the aortic valve and

coronary buttons. This revealed significant narrowing of the

ostium of the left coronary button, and this anastomosis was

subsequently revised. An intra-aortic balloon pump was placed

via the left femoral artery. The patient was warmed and weaned

from bypass; however, the sternum was not closed con-

cern for ongoing LV dysfunction. After 2 days in the ICU, the

patient stabilized with improvement in LV function and

returned to the operating room for IABP removal and sternal

closure. After an uneventful remaining course, the patient was

discharged to home 9 days later.

DISCUSSION

Limited data exist with regard to aortic dissections that occur

subsequent to a Ross procedure. However, among patients who

have undergone conventional aortic valve replacement, the

incidence of dissection approaches 27% in patients with aortic

dilation >5.0 cm, as compared to an incidence of 0.6% overall

[4]. To the best of our knowledge, only four cases of aortic dis-

section following the Ross procedure have been reported. One

involved a patient with a Debakey Type II dissection 6 years

postoperatively, which was repaired with a Dacron tube graft

[5]. Another patient suffered an aortic dissection 7 years after

a Ross procedure, which was repaired utilizing the Yacoub

technique (remodeling), again with a Dacron graft [6]. The other

two cases involved a 50-year-old woman and a 50-year-old

man who suffered dissections at 9 and 5 years post-Ross proce-

dure, respectively [7,8]. Our case is unique in that the event

of dissection was temporally separated from the initial Ross

procedure by a longer time interval, 16 years.

Pertinent to our patient, whose original aortic valvulopathy

was related to a native bicuspid aortic valve, is the question of

whether the aneurysmal changes of the autograft were also

mediated by connective tissue abnormalities. In fact, pathologi-

cal examination of this patient’s operative specimen revealed

medial degeneration with mucoid extracellular matrix accumu-

lation, fragmentation of elastic fibers and loss of smooth mus-

cle nuclei (Fig. 3), consistent with an underlying connective

tissue disorder. Indeed, studies have identified histopathologi-

cal irregularities in patients with a bicuspid aortic valve. One

study of bicuspid aortic valve patients found that almost half

had degenerative changes in the aorta (cystic medial necrosis,

fragmentation and loss of elastic fibers and deposition of muco-

polysaccharide material), and 75% had pulmonary trunk degen-

eration [3].

Other studies have shown that as many as 13% of patients

with an aortic dissection have a concomitant congenital defect

of the aortic valve [9]. Further evidence of a genetic contribu-

tion is suggested by reports of familial bicuspid aortic valve dis-

ease. In these families, an increased incidence of dilation and

dissection has been observed [10]. A defect in neural crest

maturation has been proposed as a potential mechanism of

Figure 1: CT of the chest. Coronal (left) and axial (right) views demonstrating pathologic dilatation of the aortic root and ascending aorta. On the axial image, a dissec-

tion plane is noted in the aortic root.

Figure 2: Gross image of the pulmonary autograft in the aortic valve position

with significant degeneration of the valve leaflets and a dissection plane (top

portion of picture) extending into the non-coronary sinus.

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M.R. Myers et al.

Source: https://www.researchgate.net/publication/301792916_Surgical_repair_of_aortic_dissection_16_years_post-Ross_procedure