Unique characteristics of the type B aortic dissection patients with malperfusion in the Vascular Quality Initiative

Interventions in Acute or Subacute Phase for Type B Aortic Dissection

The treatment strategy for acute and subacute Stanford type B aortic dissection has changed significantly since the advent of thoracic endovascular aortic repair (TEVAR). Indication for invasive treatment: In addition to the conventional complicated cases (rupture or malperfusion case), the indication for invasive treatment now includes cases with refractory hypertension, persistent or recurrent pain, large aortic diameter, and other conditions that are considered to have a poor prognosis with conservative treatment. Treatment methods: TEVAR is the first choice for acute, subacute, and early chronic-stage treatment, and when this is not possible, other techniques (fenestration and graft replacement) are chosen. Treatment timing: The timing of invasive treatment should be emergent in life-threatening conditions (for rupture or malperfusion case) and immediate in symptomatic cases, while in other cases, preemptive TEVAR is considered appropriate on a scheduled timing within 6 months of onset. (This is a translation of Jpn J Vasc Surg 2023; 32: 157-163.).

Endovascular stenting of the ascending aorta for visceral malperfusion in a patient with type A aortic dissection

A type A aortic dissection is a challenging condition for both cardiothoracic and vascular surgeons. Although open surgery remains the gold standard, there is considerable interest in the use of endovascular techniques for patients who present with malperfusion. We present the case of an unstable 55-year-old man with visceral malperfusion from a type A dissection who was stabilized using an endovascular technique as a bridge to open surgery. A bare metal thoracic endograft was used in the ascending aorta to rapidly restore perfusion. This hybrid approach to the problem of malperfusion in type A dissection could be useful for these patients with complicated cases.

Readmission after early thoracic endovascular aortic repair versus medical management of acute type B aortic dissection

BACKGROUND

The use of thoracic endovascular aortic repair (TEVAR) for the management of acute uncomplicated type B aortic dissection (TBAD) has increased. Although the results from early studies were promising, larger randomized trials evaluating TEVAR are lacking. It is also unclear where sufficient equipoise exists for such trials. In the present study, we evaluated the number of readmissions and unplanned operations after TEVAR vs those after medical management as the initial treatment of acute uncomplicated TBAD and the frequency of each treatment in this population.

METHODS

We performed a multi-institutional retrospective review of patients with acute TBAD from 2015 to 2020 with the 1-year outcomes available, excluding patients with prior aortic intervention or chronic, iatrogenic or traumatic etiologies. The primary exposure was TEVAR vs medical management at the index admission. The patient demographics, clinical presentation, and imaging findings were analyzed using bivariate and multivariate logistic regression for the primary outcomes of unplanned readmission and/or operation after the initial admission. The secondary outcomes were mortality, myocardial infarction, stroke, renal failure requiring dialysis, retrograde type A dissection, and length of stay. We hypothesized that the readmissions would be higher with medical management.

RESULTS

A total of 216 patients with TBAD (47 with complicated and 169 with uncomplicated) from two large academic centers were identified. Of the 169 patients with uncomplicated TBAD, 83 (49%) had been treated medically and 86 (51%) had undergone TEVAR at the initial admission. No differences were found in the demographics or high-risk imaging features at presentation. The medically managed patients had had higher rates of unplanned readmission (34% vs 9%; P = .0001) and operation (28% vs 8%; P = .0007) but shorter lengths of stay (6.3 vs 13.1 days; P < .0001). No differences were found in mortality, although the rate of myocardial infarction was higher in the medically managed group (10.8% vs 2.3%; P = .02). Although 28% of the medically managed patients had later required operation, they had had morbidity and mortality similar to those of patients who had undergone initial TEVAR. Initial medical management was associated with unplanned readmission (odds ratio, 8.3; P = .02) and the need for operation (odds ratio, 4.56; P = .006). No differences were found in the outcomes according to the involved aortic zones.

CONCLUSIONS

In the present study, medical management of acute uncomplicated TBAD was associated with higher rates of readmission and the need for unplanned operation compared with TEVAR. However, no differences were found in the 1-year mortality for the patients for whom medical management had failed. Because one half of the patients had undergone medical management and one half had undergone early TEVAR, this finding suggests clinical equipoise for the treatment of acute uncomplicated TBAD. Therefore, a larger randomized trial appears warranted to determine whether a clear benefit exists for early TEVAR.

Thoracic Endovascular Aortic Repair (TEVAR) First in Patients with Lower Limb Ischemia in Complicated Type B Aortic Dissection: Clinical Outcome and Morphology

Acute Type B aortic dissection (TBAD) can cause organ malperfusion, e.g., lower limb ischemia (LLI). Thoracic endovascular aortic repair (TEVAR) represents the standard treatment for complicated TBAD; however, with respect to LLI, data is scant. The aim of this study was to investigate clinical and morphological outcomes in patients with complicated TBAD and LLI managed with a "TEVAR-first" policy. Between March 1997 and December 2021, 731 TEVAR-procedures were performed, including 106 TBAD-cases. Cases with TBAD + LLI were included in this retrospective analysis. Study endpoints were morphological/clinical success of TEVAR, regarding aortic and extremity-related outcome, including extremity-related adjunct procedures (erAP) during a median FU of 28.68 months. A total of 20/106 TBAD-cases (18.8%, 32-82 years, 7 women) presented with acute LLI (12/20 Rutherford class IIb/III). In 15/20 cases, true lumen-collapse (TLC) was present below the aortic bifurcation. In 16/20 cases, TEVAR alone resolved LLI. In the remaining four cases, erAP was necessary. A morphological analysis showed a relation between lower starting point and lesser extent of TLC and TEVAR success. No extremity-related reinterventions and only one major amputation was needed. The data strongly suggest that aTEVAR-first-strategy for treating TBAD with LLI is reasonable. Morphological parameters might be of importance to anticipate the failure of TEVAR alone.

Risk factors and treatment outcomes for type B aortic dissection with malperfusion requiring adjunctive procedures after thoracic endovascular aortic repair

OBJECTIVE

To investigate the risk factors for unrelieved malperfusion after thoracic endovascular aortic repair (TEVAR) alone.

METHODS

From January 2009 to December 2019, 86 patients with type B aortic dissection-induced malperfusion were enrolled. Demographics and clinical and imaging data, as well as treatment outcomes, were collected and compared between patients with malperfusion relieved by TEVAR alone (TR) or by TEVAR with adjunctive procedures (TA).

RESULTS

Among the 86 enrolled patients, 17 (19.8%) had malperfusion requiring TA. Patients in the TA group were more likely to suffer lower limb ischemia (P = .004), present with severe ischemia (P = .003), and have more than one end-organ ischemia (P = .015). There were more involved vessels classified as the mixed type in the TA group (P = .002). Mixed ischemia was the only independent risk factor for malperfusion requiring TA (odds ratio, 4.7; 95% confidence interval [CI], 1.3-17.2; P = .017). The ischemia-related in-hospital mortality rate of the TA group was significantly higher than that of the TR group (P = .023), and malperfusion requiring TA was the only risk factor in the multivariate logistic regression (odds ratio, 14.6; 95% CI, 1.4-150.5; P = .025). The 5-year overall cumulative survival rates were 82.4% (95% CI, 66.1%-100.0%) in the TA group and 89.5% (95% CI, 81.6%-98.1%) in the TR group (P = .294).

CONCLUSIONS

Type B aortic dissection-induced malperfusion requiring TA was associated with a higher ischemia-related in-hospital mortality rate. Mixed obstruction was an independent risk factor for unrelieved malperfusion after TEVAR alone, and early identification of potential patients requiring TA could thereby be achieved. Reasonable treatment strategies could contribute to the successful management of malperfusion requiring TA.