Long-term fate of aortic branches in patients with aortic dissection

Carotid versus axillary artery cannulation for descending aorta remodeling in type A acute aortic dissection

BACKGROUND

Arterial cannulation sites for the surgical repair of type A aortic dissection (AAD) have evolved from right axillary artery (AA) cannulation to bilateral carotid artery (CA) based of femoral artery (FA) cannulation. Postoperative descending aorta remodeling is closely linked to the false lumen area ratio (FLAR), defined as false lumen area/aortic area, as well as to the incidence of renal replacement therapy (RRT).

AIM

To investigate the effect of the updated arterial cannulation strategy on descending aortic remodeling.

METHODS

A total of 443 AAD patients who received FA combined cannulation between March 2015 and March 2023 were included in the study. Of these, 209 received right AA cannulation and 234 received bilateral CA cannulation. The primary outcome was the change in FLAR, as calculated from computed tomography angiography in three segments of the descending aorta: Thoracic (S1), upper abdominal (S2), and lower abdominal (S3). Secondary outcomes were the incidence of RRT and the serum inflammation response, as observed by the levels of high sensitivity C reaction protein (hs-CRP) and Interleukin-6 (IL-6).

RESULTS

The postoperative/preoperative ratio of FLAR in S2 and S3 was higher in the AA group compared to the CA group (S2: 0.80 ± 0.08 vs 0.75 ± 0.07, P < 0.001; S3: 0.57 ± 0.12 vs 0.50 ± 0.12, P < 0.001, respectively). The AA group also had a significantly higher incidence of RRT (19.1% vs 8.5%, P = 0.001; odds ratio: 2.533, 95%CI: 1.427-4.493) and higher levels of inflammation cytokines 24 h after the procedure [hr-CRP: 117 ± 17 vs 104 ± 15 mg/L; IL-6: 129 (103, 166) vs 83 (69, 101) pg/mL; both P < 0.001] compared to the CA group.

CONCLUSION

The CA cannulation strategy was associated with better abdominal aorta remodeling after AAD repair compared to AA cannulation, as observed by a greater change in FLAR and lower incidence of RRT.

Predictors of Intervention in Acute Type B Aortic Penetrating Ulcer and Intramural Hematoma

We aimed to investigate predictors of intervention of acute type B aortic penetrating ulcer (PAU) and intramural hematoma (IMH). We conducted a retrospective chart review of all patients admitted for acute type B PAU or IMH in a tertiary referral hospital. Indications to intervention were "complicated" (rupture, impending rupture, malperfusion) or "high risk for unfavorable outcome" (refractory hypertension and/or pain despite best medical treatment, morphologic aortic evolution, transition to a new aortic syndrome, or increase in IMH/PAU depth >5 mm) during the acute/subacute phase. The primary outcomes were overall mortality, aortic-related mortality, and freedom from intervention. Time-dependent outcomes were estimated with Kaplan-Meier curves. Cox proportional hazards models were used to identify predictors of intervention and mortality. There were 54 acute aortic syndromes, 37 PAUs and 17 IMHs. Mean age was 69 ± 14 years and 33 patients (62.2%) were male. Six (11.5%) patients had complicated aortic syndromes and underwent urgent repair. Two (3.7%) additional patients developed an impending rupture during the acute phase. Eleven (21.1%) patients were classified as at "high risk" during the initial hospitalization. Overall, 22 (40.7%) patients required an aortic intervention during the initial admission (n = 16, 72.7% during the acute phase; n = 6, 27.3% during the subacute phase). In-hospital mortality was 5.5% (1 PAU and 2 IMH), and was aorta-related in all cases. For IMH, disease extension in >3 aortic zones (HR 1.94, 95%CI 1.17-32.6; p = 0.038) and presence of ulcer-like projections (ULPs) (HR 1.23, 95%CI 1.02-9.41; p = 0.042) were associated with the need for intervention. There were no aortic-related deaths or intervention during the chronic phase. PAU width >20 mm (HR 1.68, 95%CI 1.07-16.08; p = 0.014), PAU depth >15 mm (HR 6.74, 95%CI 1.31-34.18; p = 021), PAU depth/total aortic diameter >0.3 (HR 4.31, 95%CI 1.17-20.32; p = 0.043), and location at the level of the paravisceral aorta (HR 2.24, 95%CI 1.23-4.70; p = 0.035) were significantly associated with need for intervention. Six additional (16.2%) PAUs required intervention during the chronic phase owing to PAU growth. Maximum aortic diameter >35 mm was significantly associated with intervention (HR 1.45, 95%CI 1.00-2.32; p = 0.037). Acute symptomatic type B IMHs and PAUs are characterized by a high risk of complications during the first month from presentation. Morphologic features associated with intervention were IMH with ULPs or extension in more than 3 aortic zones, as well as PAUs with depth>15 mm, width >20 mm, or depth/aortic diameter ratio>0.3. A strict follow-up protocol or consideration for early intervention within 30 days from presentation should be taken into account for these high-risk patients. During the chronic phase imaging follow-up is particularly important for PAUs in order to identify progression to saccular aneurysms.

Thoracoabdominal aortic aneurysm in connective tissue disorder patients

Connective tissue disorders (CTDs) are a group of genetically triggered diseases in which the primary defect involves collagen and elastin protein assembly with potential vascular degenerations such as thoracoabdominal aortic aneurysm (TAAA) and dissection. These most commonly include Marfan syndrome, Ehlers-Danlos syndrome, Loeys-Dietz syndrome, and familial thoracic aortic aneurysm and dissection. Open surgical repair represents the standard approach in this specific group of patients. Extensive aortic replacements are generally performed in order to reduce long-term complications caused by the progressive dilatation of the remnant aortic segments. In the last decades, endovascular interventions have emerged as a valid alternative in patients affected by degenerative TAAA. However, in patients with CTD, this approach presents higher rates of reinterventions and postoperative complications with a disputable long-term durability, and it is nowadays performed for very selective indications such as severe comorbidities and urgent/emergent settings. Despite a deeper knowledge of the pathophysiological mechanisms involved in CTD, improvements in medical therapy, and a multidisciplinary approach fully involved in the management of these usually frailer patients, this specific group still represents a challenge. Further dedicated studies addressing mid-term and long-term outcomes in this selected population are needed.

Predictors of Long-Term Aortic Growth and Disease Progression in Patients with Aortic Dissection, Intramural Hematoma, and Penetrating Aortic Ulcer

BACKGROUND

We aimed to identify predictors of long-term aortic diameter change and disease progression in a population cohort of patients with newly diagnosed aortic dissection (AD), intramural hematoma (IMH), or penetrating aortic ulcer (PAU).

METHODS

We used the Rochester Epidemiology Project record linkage system to identify all Olmsted County, MN-USA, residents diagnosed with AD, IMH, and PAU (1995-2015). The endpoints were aortic diameter change, freedom from clinical disease progression (any related intervention, aortic aneurysm, new aortic syndrome, rupture or death) and disease resolution (complete spontaneous radiological disappear). Linear regression was used to assess aortic growth rate; predictors of disease progression were identified with Cox proportional hazards.

RESULTS

Of 133 incident cases, 46 ADs, 12 IMHs, and 28 PAUs with sufficient imaging data were included. Overall median follow-up was 8.1 years. Aortic diameter increase occurred in 40 ADs (87%, median 1.0 mm/year), 5 IMHs (42%, median 0.2 mm/year) and 14 PAUs (50%, median 0.4 mm/year). Symptomatic presentation (P = 0.045), connective tissue disorders (P = 0.005), and initial aortic diameter >42 mm (P = 0.013) were associated with AD growth rate. PAU depth >9 mm (P = 0.047) and female sex (P = 0.013) were associated with aortic growth rate in PAUs and IMHs. At 10 years, freedom from disease progression was 22% (95% CI 12-41) for ADs, 44% (95% CI 22-92) for IMHs, and 46% (95% CI 27-78) for PAUs. DeBakey I/IIIB AD (HR 3.09; P = 0.038), initial IMH aortic diameter (HR 1.4; P = 0.037) and PAU depth >10 mm (HR 3.92; P = 0.018) were associated with disease progression. No AD spontaneously resolved; resolution rate at 10 years was 22% (95% CI 0-45) for IMHs and 11% (95% CI 0-23) for PAUs.

CONCLUSIONS

Aortic growth and clinical disease progression are observed in most patients with aortic syndromes, while spontaneous resolution is uncommon. Predictors of aortic growth and disease progression may be used to tailor appropriate follow-up and eventual early intervention.