A comparison of endovascular repair to medical management for acute vs subacute uncomplicated type B aortic dissections

Pre-Emptive Endovascular Repair for Uncomplicated Type B Dissection - Is This an Option?

Type B aortic dissection (TBAD) primarily affects men aged 60-65 years, with hypertension in over 80% of cases. The gold standard for the treatment of uncomplicated acute TBAD is Best Medical Treatment (BMT), which focused on controlling blood pressure and heart rate. However, Thoracic Endovascular Aortic Repair (TEVAR) has gained attention over the years, especially for complicated TBAD cases, by covering the primary entry tear, lowering false lumen pressure, and promoting aortic remodeling. TBAD can be classified according to the onset of symptoms into acute, subacute and chronic stages, with different intervention implications at each stage. Studies such as the Acute Dissection Stentgraft OR Best Medical Treatment and Investigation of STEnt grafts in Acute Dissection trials have shown the benefits of TEVAR over BMT, particularly in promoting aortic remodeling and reducing long-term aorta-related mortality. However, these trials noted no significant difference in immediate mortality. TEVAR timing is crucial, as early intervention in the acute phase can lead to higher complication rates due to higher intimal fragility. As a result, the subacute phase offers a balance, allowing beneficial remodeling with a lower complication rate.

Midterm outcomes of thoracic endovascular aortic repair versus optimal medical therapy for uncomplicated acute type B dissection

Objective

We sought to compare the early and midterm outcomes of thoracic endovascular aortic repair (TEVAR) versus optimal medical therapy (OMT) for uncomplicated acute type B aortic dissection.

Methods

Data were analyzed for 200 consecutive patients with uncomplicated acute type B aortic dissection from February 1992 to July 2022, including 147 with initial OMT and 53 undergoing TEVAR at index hospitalization. Baseline, intraoperative, and postoperative data, survival, and (re)intervention were compared between the two strategies.

Results

In-hospital/30-day mortality was 7.5% (15/200) for the entire series, which was significantly lower in the TEVAR group compared with the OMT group (0 vs 10.2% [15/147]; P = .013). Thirty-day rates were 5.7% (3/53) for reintervention after TEVAR and 15.6% (23/147) for intervention after OMT (P = .064). Death within 30 days of (re)intervention was 0 (n = 0) in the TEVAR group and 18.4% (n = 14) in the OMT group (P = .063). There were no significant differences in the incidences of stroke, paraplegia, acute kidney injury, sepsis, or malperfusion syndrome after initial treatment. Kaplan-Meier survival in the TEVAR group was 92.3% (95% CI, 80.7-97.0) at 1 year and 3 years, significantly higher than in the OMT group (80.3% [95% CI, 72.8-85.8] and 71.4% [95% CI, 63.4-78.0]; P = .012). In patients aged 65 years or more, TEVAR also achieved a significantly higher survival, which was 93.7% (95% CI, 77.5-98.3 vs 69.7% [95% CI, 58.0-78.7]) at 1 year and 93.7% (95% CI, 77.3-98.3] vs 60.5% [95% CI, 48.7-70.5]) at 3 years (P < .001).

Conclusions

In this single-institution experience, upfront TEVAR performed at index hospitalization for uncomplicated acute type B aortic dissection was associated with improved survival at early and midterm follow-up.

Time is Aorta in Uncomplicated Type B Aortic Dissection

BACKGROUND

Although cardiovascular control optimization through best medical therapy remains the gold standard of treatment for uncomplicated type B aortic dissection (uTBAD) according to international guidelines, thoracic endovascular aortic repair (TEVAR) has increasingly emerged as a viable and appealing treatment option due to its potential to induce favorable aortic remodeling and improve long-term outcomes. However, the optimal timing of TEVAR in uTBAD remains a subject of debate. This narrative review aims at evaluating safety, efficacy, and outcomes of TEVAR at different time points of the disease history.

METHODS

We conducted a comprehensive literature review across multiple electronic databases, including PubMed and Scopus, to synthesize research evidence on the timing of TEVAR in uTBAD.

RESULTS

Hyperacute-phase TEVAR (<24 hours) is associated with prohibitive periprocedural risks and is thus discouraged. Acute-phase TEVAR (1-14 days) may provide benefits in aortic remodeling but it is burdened by rather elevated rates of early complications and reinterventions. The subacute phase (14-90 days) is consistently identified as the optimal therapeutic window, balancing procedural safety and efficacy, with studies reporting superior outcomes in terms of mortality, complications, and aortic remodeling. Chronic-phase TEVAR (>90 days), although sometimes necessary in cases of disease progression, is associated with poorer outcomes, including higher rates of reintervention, complications, and limited aortic remodeling with respect to the subacute phase.

CONCLUSION

The consistent findings across the studies analyzed indicate that the subacute phase offers the best combination of reduced procedural risks and favorable long-term outcomes. However, stronger evidence is needed to refine timing strategies.

Efficacy of intentional undersized thoracic endovascular repair for Stanford type B aortic dissection

OBJECTIVE

Thoracic endovascular aneurysm repair (TEVAR) is widely used for the treatment of aortic dissection. Endograft oversizing is a risk factor for stent graft-induced new entry tears and retrograde type A aortic dissection. However, there is no clear consensus on the optimal graft size selection for Stanford type B acute or subacute aortic dissection (TBAD). Herein, we examined the safety and efficacy of TEVAR using an intentionally undersized endograft to treat TBAD.

METHODS

This retrospective chart review study included 82 patients who underwent TEVAR for acute or subacute Stanford TBAD between 2015 and 2022. We measured the true lumen diameter just distal to the subclavian artery and opted for a stent graft of the same diameter. In instances where deformation resulting from false lumen pressure displacement was pronounced, we measured the diameter at the site just proximal to the subclavian artery. Patients' characteristics, procedural, in-hospital, and follow-up data, and aortic remodeling were analyzed. The aortic diameter was analyzed using one-way analysis of variance followed by Dunnett's test. Survival and freedom from reintervention were estimated using Kaplan-Meier curves.

RESULTS

The follow-up rate was 98.4%. The mean age was 58.3 ± 12.3 years, and 76 were men (92.7%). The mean diameters of the stent graft and native proximal landing zone were 30.9 ± 3.2 mm and 30.8 ± 3.0 mm, respectively. The oversize rate of the stent graft in relation to the native proximal aortic diameter was 0.3% ± 4.7%. In-hospital mortality was observed in one patient, retrograde type A aortic dissection in one patient, distal stent graft-induced new entry tear in zero patients, and type 1a endoleak in 22 patients (26.8%). Type 1a endoleaks, characterized by antegrade false lumen blood flow originating from the primary entry, in 12 patients spontaneously disappeared within 1 year of follow-up. According to aortic remodeling, 59 patients (86.8%) achieved complete aortic remodeling at the aortic arch level and 51 (75.0%) at the eighth thoracic vertebral level. The diameters of the aortic arch and descending aorta were significantly reduced compared with the postoperative measurements (P <.001). Survival rates were 97.5% and 93.6% at 1 and 3 years, respectively. Freedom from reintervention was 84.7% and 84.7% at 1 and 3 years, respectively.

CONCLUSIONS

Intentionally undersized TEVAR was safe and achieved acceptable aortic remodeling despite a high rate of type 1a endoleaks. A type 1a endoleak was acceptable as it primarily diminished during the mid-term follow-up.

Optimal Timing of Pre-emptive Thoracic Endovascular Aortic Repair in Uncomplicated Type B Aortic Dissection: A Network Meta-Analysis

BACKGROUND

This network meta-analysis compares outcomes of optimal medical therapy (OMT) and pre-emptive thoracic endovascular aortic repair (TEVAR) for uncomplicated type B aortic dissection at different phases of chronicity.

METHODS

MEDLINE and EMBASE were searched through November 2023. Pooled short-term outcomes (short-term mortality, perioperative complications) and long-term outcomes (all-cause mortality, aortic-related mortality, aortic re-intervention rates) were calculated.

RESULTS

Systematic review identified 17 studies (2 randomized controlled trials, 3 propensity score matching, and 2 inverse probability weighting). Subacute-phase intervention had lower short-term mortality than the acute-phase (hazard ratio [HR] [95% confidence interval [CI]]=0.60 [0.38-0.94], p=0.027). No significant differences were observed in aortic rupture and paraplegia. Acute-phase TEVAR had a higher stroke incidence than subacute-phase intervention (HR [95% CI]=2.63 [1.36-5.09], p=0.042), chronic (HR [95% CI]=2.5 [1.03-6.2], p=0.043), and OMT (HR [95% CI]=1.57 [1.12-2.18], p=0.008). Acute-phase TEVAR had higher long-term all-cause mortality than subacute-phase intervention (HR [95% CI]=1.34 [1.03-1.74], p=0.03). Optimal medical therapy had elevated long-term all-cause mortality compared with subacute-phase TEVAR (HR [95% CI]=1.67 [1.25-2.33], p<0.001) and increased long-term aortic-related mortality vs acute-phase (HR [95% CI]=2.08 [1.31-3.31], p=0.002) and subacute-phase (HR [95% CI]=2.6 [1.62-4.18], p<0.01) interventions. No significant differences were observed in aortic re-intervention rates.

CONCLUSIONS

Pre-emptive TEVAR may offer lower all-cause mortality and aortic-related mortality than OMT. Considering lower short-term mortality, perioperative stroke rate, and long-term mortality, our findings support pre-emptive TEVAR during the subacute phase.

CLINICAL IMPACT

The optimal timing of pre-emptive thoracic endovascular aortic repair (TEVAR) for uncomplicated type B aortic dissection remains uncertain. This network meta-analysis suggests that the subacute phase (14-90 days from symptom onset) emerges as the optimal timing for pre-emptive TEVAR. This window is associated with lower rates of short-term complications and higher long-term survival rates compared with alternative strategies.