Report on the results of thoracic endovascular aortic repair for acute, complicated, type B aortic dissection at 30 days and 1 year from a multidisciplinary subcommittee of the Society for Vascular Surgery Outcomes Committee

A Systematic Review and Meta-Analysis of Current Evidence Related to the Impact of Endovascular Repair Timing on Prognosis of Acute Stanford Type B Aortic Dissection

BACKGROUND

The objective of this study was to determine whether thoracic endovascular aortic repair (TEVAR) timing is more beneficial in the acute phase (first 14 days) than in the subacute phase (14-90 days) for the administration of acute Stanford type B aortic dissection (TBAD).

METHODS

A comprehensive literature search was conducted in databases (EMBASE, PubMed and Cochrane Library) until December 2023 to identify studies reporting the results of TEVAR used for patients with acute TBAD. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated utilizing either the random-effects model or the fixed-effects model.

RESULTS

A total of 25 studies involving 4,827 individuals with TBAD (including 1,609 with subacute TBAD) met our selection criteria. Early results revealed a lower incidence of Ia endoleaks (OR, 1.55; 95% CI, 1.03-2.33; P = 0.04) and aortic ruptures (OR, 2.89; 95% CI, 0.98-8.50; P = 0.05) in subacute TBAD. Apart from these findings, there was little difference in other incidents between the 2 groups. Regarding late outcomes, we observed significantly higher rates of retrograde dissection (OR, 2.12; 95% CI, 1.04-4.34; P = 0.04), distal stent-induced new entry (OR, 2.39; 95% CI, 1.24-4.61; P = 0.009), and reintervention (OR, 1.45; 95% CI, 0.05-1.99; P = 0.02) in acute TBAD than in subacute TBAD, whereas no significant differences were found for other outcomes between the 2 groups. Also, TEVAR appeared to yield comparable results for false lumen thrombosis and true lumen regression in both groups.

CONCLUSIONS

Subacute TBAD repair with TEVAR demonstrates a more effective reduction in adverse event rates compared to immediate treatment in the acute phase.

Current perspectives in acute type B aortic dissections: a literature review

In this new millennial, endovascular strategies have revolutionized the treatment of acute type B aortic dissection (aTBAD). With reduced in-hospital mortality and good long-term outcomes TEVAR has become the gold standard for the treatment of complicated dissection and is gaining increasing support for its preventive applicability in some uncomplicated dissections. With this new paradigm came a shift of the treatment goal where just covering the entry tear is not enough and instead achieving long-term positive thoracoabdominal remodeling is needed. More extensive approaches with composite device designs (covered stent graft and bare metal stent) emerged to answer this aortic conundrum. At 5-year of follow-up, "Provisional ExTension To Induce COmplete Attachment technique" (PETTICOAT) and its evolution "Stent assisted balloon induced intimal disruption and relamination in aortic dissection repair" (STABILISE) seem to be safe techniques that can allow, when anatomically feasible, excellent aortic remodeling and, in some cases, even the healing of the dissection. Nevertheless, STABILISE results, although promising, are mostly based on small series and therefore need to be validated by analyzing medium-long-term results from the international registry. Given the plethora of new data and the disparity of expert opinions on the best treatment to adopt, in this review we aim to summarize the current knowledge on the results of these different strategies for acute TBAD.

Late Referral and Patient Transfer is Associated with Worse Outcomes for Patients Presenting with Initially Uncomplicated Type B Aortic Dissections

BACKGROUND

Acute type B aortic dissections (TBADs) can become complicated at any time point, necessitating surgical repair. We sought to investigate the effect of interhospital transfer on the development of delayed complications in acute type B aortic dissection (dcTBAD).

METHODS

All patients who presented with acute TBAD to a tertiary aortic center from 2015 to 2019 were analyzed. Patients were divided into initially complicated type B aortic dissection (icTBAD) (0-24 hours from symptom onset), dcTBAD (25 hours to 14 days), and uncomplicated type B aortic dissection (ucTBAD) groups. Criteria for complicated dissection were aortic rupture, malperfusion, or rapid aortic growth. Demographics, patient history, the timing of presentation, imaging findings, and clinical outcomes were compared between groups.

RESULTS

Of 120 acute TBADs included, 27 (22%) were initially complicated (aortic rupture, n = 9; malperfusion, n = 18). Twenty-one (18%) developed delayed complications (aortic rupture, n = 3; malperfusion, n = 14; rapid growth, n = 4) at a median of 7.0 [4.0, 9.0] days from symptom onset. Seventy-two (60%) remained uncomplicated. Overall, 111 (93%) presented as transfers from outside hospitals (icTBAD, n = 25; dcTBAD, n = 21; ucTBAD, n = 65). Of those, dcTBADs were more likely to have a prolonged delay between presentation to the outside hospital and referral to the tertiary center compared to ucTBADs (median = 1.00 [0.0, 5.0] days delayed vs. 0.00 [0.0, 0.0] days delayed; P < 0.001). Initially uncomplicated patients referred for transfer ≥24 hours from presentation went on to develop dcTBAD more often than those transferred in <24 hours (73% vs 13%; P < 0.001). Of dcTBADs, 38% had no high-risk features on initial imaging. Patients with dcTBAD had significantly longer length of stay (median = 12 vs 7 days; P = 0.006). In-hospital mortality was significantly higher in dcTBADs than ucTBADs (9.5% vs 0%; P = 0.047). In-hospital mortality was not significantly different between dcTBADs and icTBADs (9.5% vs. 11%; P > 0.05).

CONCLUSIONS

The incidence and consequence of dcTBADsare not insignificant. Late referral and transfer to a tertiary aortic center (≥24 hours from initial presentation) was associated with dcTBADsrequiring surgical intervention. The development of dcTBADwas associated with increased length of stay and increased in-hospital mortality.

Advanced Endovascular Treatment of Complex Aortic Pathology

Endovascular aortic aneurysm repair and thoracic endovascular aortic repair have been shown to reduce blood loss, operative time, length of hospital stay, mortality, and morbidity compared with open surgical repair for abdominal aortic aneurysms and thoracic aortic aneurysms. However, there are anatomical constraints that limit the application of the endovascular approach in 30% to 40% of patients, including those with short necks, excessive angulation, or aneurysms with the involvement of aortic side branches such as supra-aortic trunks, arch aneurysms, visceral arteries, or internal iliac arteries.

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.

Successful one-stage operation for type B acute intramural hematoma with descending aortic rupture

A 76-year-old man who complained of back pain was referred to our hospital. Computed tomography revealed an intramural hematoma with a descending aortic rupture. Total arch replacement with the frozen elephant trunk technique and thoracic endovascular aortic repair was performed emergently in one stage. The patient was discharged without symptoms.

TEVAR for complicated and uncomplicated type B aortic dissection-Systematic review and meta-analysis

BACKGROUND

Type B aortic dissection (TBAD), is defined as a dissection involving the aorta distal to left subclavian artery with the ascending aorta and the aortic arch not affected. TBAD is classified due to the time frame and presence of complications. Complicated TBAD (co-TBAD) patients have a greater mortality rate than uncomplicated TBAD (un-TBAD) and thoracic endovascular aortic repair (TEVAR) is considered the gold-standard intervention for these clinical challenges.

METHODS

We undertook a systematic review of the literature regarding TEVAR intervention in co-TBAD and un-TBAD. A comprehensive search was undertaken across four major databases and was evaluated and assessed until June 2020.

RESULTS

A total of 16,104 patients were included in the study (7772 patients co-TBAD and 8352 un-TBAD). A significantly higher proportion of comorbidities were seen in co-TBAD patients compared with un-TBAD. Acute dissection was more frequent in the co-TBAD group (73.55% vs. 66.91%), while chronic dissection was more common in un-TBAD patients (33.8% vs. 70.73%). Postprocedure stroke was higher in co-TBAD (5.85% vs. 3.92%; p < .01), while postprocedural renal failure was higher in un-TBAD patients (7.23 vs. 11.38%; p < .01). No difference was observed in in-hospital mortality however the 30 days mortality was higher in the co-TBAD group. One-year survival was higher in the uncomplicated group but this difference was not observed in the 5-year survival.

CONCLUSION

In our analysis we can appreciate that despite significantly higher comorbidities in the co-TBAD cohort, there was no difference in in-hospital mortality between the two groups and the 5-year survival did not have any difference.

Adjunctive false lumen intervention for chronic aortic dissections is safe but offers unclear benefit

OBJECTIVE

Adjunctive false lumen embolization (FLE) with thoracic endovascular aortic repair (TEVAR) in patients with chronic aortic dissection is thought to induce FL thrombosis and favorable aortic remodeling. However, these data are derived from small single-institution experiences and the potential benefit of FLE remains unproven. In this study, we examined perioperative and midterm outcomes of patients with aortic dissection undergoing concomitant TEVAR and FLE.* METHODS: Patients 18 or older who underwent TEVAR for chronic aortic dissection with known FLE status in the Society for Vascular Surgery Vascular Quality Initiative database between January 2010 and February 2020 were included. Ruptured patients and emergent procedures were excluded. Patient characteristics, operative details and outcomes were analyzed by group: TEVAR with or without FLE. Primary outcomes were in-hospital post-operative complications and all-cause mortality. Secondary outcomes included follow-up mean maximum aortic diameter change, rates of false lumen thrombosis, re-intervention rates, and mortality.

RESULTS

884 patients were included: 46 had TEVAR/FLE and 838 had TEVAR alone. There was no significant difference between groups in terms of age, gender, comorbidities, prior aortic interventions, mean maximum pre-operative aortic diameter (5.1cm vs. 5.0cm, P=0.43), presentation symptomatology, or intervention indication. FLE was associated with significantly longer procedural times (178min vs. 146min, P=0.0002), increased contrast use (134mL vs. 113mL, P=0.02), and prolonged fluoroscopy time (34min vs. 21min, P<0.0001). However, FLE was not associated with a significant difference in post-operative complications (17.4% vs. 13.8%, P=0.51), length of stay (6.5 vs. 5.7 days, P=0.18), or in-hospital all-cause mortality (0% vs. 1.3%, P=1). In mid-term follow-up (median 15.5months, IQR 2.2-36.2 months), all-cause mortality trended lower, but was not significant (2.2% vs. 7.8%); and Kaplan-Meier analysis demonstrated no difference in overall survival between groups (P=0.23). By Cox regression analysis, post-operative complications had the strongest independent association with all-cause mortality (HR 2.65, 95% CI 1.56-4.5, P<0.001). In patients with available follow-up imaging and re-intervention status, mean aortic diameter change (n=337, -0.71cm vs. -0.69cm, P=0.64) and re-intervention rates (n=487, 10% vs. 11.4%, P=1) were similar.

CONCLUSIONS

Adjunctive FLE, despite increased procedural times, can be performed safely for patients with chronic dissection without significantly higher overall perioperative morbidity or mortality. TEVAR/FLE demonstrates trends for improved survival and increased rates of FL thrombosis in the treated thoracic segment; however, given the lack of evidence to suggest a significant reduction in re-intervention rates or induction of more favorable aortic remodeling compared to TEVAR alone, the overall utility of this technique in practice remains unclear. Further investigation is needed to determine the most appropriate role for FLE in managing chronic aortic dissections.

Prognostic dynamic nomogram integrated with metabolic acidosis for in-hospital mortality and organ malperfusion in acute type B aortic dissection patients undergoing thoracic endovascular aortic repair

BACKGROUND

Organ malperfusion is a lethal complication in acute type B aortic dissection (ATBAD). The aim of present study is to develop a nomogram integrated with metabolic acidosis to predict in-hospital mortality and organ malperfusion in patients with ATBAD undergoing thoracic endovascular aortic repair (TEVAR).

METHODS

The nomogram was derived from a retrospectively study of 286 ATBAD patients who underwent TEVAR from 2010 to 2017 at a single medical center. Model performance was evaluated from discrimination and calibration capacities, as well as clinical effectiveness. The results were validated using a prospective study on 77 patients from 2018 to 2019 at the same center.

RESULTS

In the multivariate analysis of the derivation cohort, the independent predictors of in-hospital mortality and organ malperfusion identified were base excess, maximum aortic diameter ≥ 5.5 cm, renal dysfunction, D-dimer level ≥ 5.44 μg/mL and albumin amount ≤ 30 g/L. The penalized model was internally validated by bootstrapping and showed excellent discriminatory (bias-corrected c-statistic, 0.85) and calibration capacities (Hosmer-Lemeshow P value, 0.471; Brier Score, 0.072; Calibration intercept, - 0.02; Slope, 0.98). After being applied to the external validation cohort, the model yielded a c-statistic of 0.86 and Brier Score of 0.097. The model had high negative predictive values (0.93-0.94) and moderate positive predictive values (0.60-0.71) for in-hospital mortality and organ malperfusion in both cohorts.

CONCLUSIONS

A predictive nomogram combined with base excess has been established that can be used to identify high risk ATBAD patients of developing in-hospital mortality or organ malperfusion when undergoing TEVAR.

Early outcomes associated with use of the Zenith TX2 Dissection Endovascular Graft for the treatment of Stanford type B aortic dissection

OBJECTIVE

To evaluate short term outcomes related to the use of the Zenith TX2 Dissection Endovascular Graft (ZDEG) and the Zenith Dissection Bare stent (ZDES) for the treatment of Stanford type B aortic dissections.

METHODS

This retrospective multicenter case cohort study collated data from 10 European institutions for patients with both complicated and uncomplicated type B aortic dissection treated with ZDEG and ZDES between 2011 and 2018. The primary end point was mortality at 30 and 90 days. Secondary end points included complications related to TEVAR, such as, type Ia endoleak, stroke, paraparesis, paraplegia, and retrograde type A dissection (RTAD). Statistical analysis was carried out using the t test, or one-way analysis of variance and the χ² or Fisher exact tests.

RESULTS

We treated 120 patients (87 male; mean age, 62.7 ± 12.2years) either in the acute 76 (63.3%), subacute 16 (13.3%), or chronic 28 (23.3%) phase. Seven patients (5.8%) died within 30 days after the index procedure and two (1.7%) between 30 and 90 days. There was one instance of postoperative RTAD in a patient treated for rupture. Stroke and paraplegia occurred in three (2.5%) and five (4.2%), patients, respectively. Eight patients (6.7%) had a type Ia endoleak in the perioperative period. There were no instances of paraplegia, no permanent dialysis, and no requirement for adjunctive superior mesenteric or celiac artery stenting in the 33 patients (27.5%) who were treated by concurrent placement of ZDES distal to the ZDEG. The length and distal oversizing of ZDEG components used was less in this group.

CONCLUSIONS

The present series demonstrates a low (<1%) RTAD rate and favorable morbidity and mortality. The lower rate of paraplegia, dialysis, and visceral artery stenting in the cohort that had adjunctive use of ZDES is compelling and merits further assessment.

Morphologic characteristics and endovascular management of acute type B dissection patients with superior mesenteric artery involvement

OBJECTIVE

Despite its association with static mesenteric malperfusion, the morphologic characteristics and optimal management of acute type B aortic dissection (ABAD) with superior mesenteric artery (SMA) involvement are poorly understood. We studied the associated risk factors and reported the outcomes of endovascular treatment.

METHODS

From May 2016 to May 2018, we examined 212 consecutive patients with ABAD in our center. Those with SMA involvement (SMAI) were included in the present study and divided into those with and without mesenteric malperfusion (MMP) according to the clinical findings. After thoracic endovascular aortic repair (TEVAR) with or without SMA revascularization, we compared the clinical data, imaging results, and outcomes for those with and without MMP.

RESULTS

Computed tomography angiography confirmed 44 cases of SMAI: 12 (27.3%) with MMP and 32 (72.7%) without MMP. The patients with MMP had presented more frequently with lower extremity malperfusion (33.3% vs 3.1%; P = .023) than had those without MMP, with an odds ratio of 14.15 (P = .047). Multivariate analysis showed that patients with a low true lumen (TL)/false lumen (FL) diameter ratio of the SMA (TL/FL-SMA <1) had a greater risk of developing MMP than those with a high TL/FL-SMA ratio of >1 (odds ratio, 8.49; 95% confidence interval, 1.24-58.26; P = .029). SMA TL thrombosis was a significant predictor of the requirement for additional SMA revascularization after TEVAR among patients with MMP (P = .045). During a mean 10-month follow-up period, complete FL thrombosis in the SMA was seen in 11 patients (25%; 33.3% with MMP vs 21.9% without MMP; P = .43). The overall mortality rate was 6.82% (16.7% in the MMP group and 3.1% in the non-MMP group; P = .09).

CONCLUSIONS

In the present study, limb ischemia and the TL/FL-SMA ratio were two independent predictors for the development of MMP in patients with ABAD and SMAI. We found that TEVAR can be safely performed for these patients, and SMA TL thrombosis predicted for the need for SMA revascularization.

Technique-Based Evaluation of Clinical Outcomes and Aortic Remodelling Following TEVAR in Acute and Subacute Type B Aortic Dissection

INTRODUCTION

To evaluate the clinical outcomes and aortic remodelling rates following thoracic endovascular aortic repair (TEVAR) for acute or subacute type B aortic dissection (TBAD) based on technique.

MATERIAL AND METHODS

All TEVARs for acute/subacute TBAD between 01/01/2008 and 01/06/2020 were included. TEVARS were grouped by technique (TEVAR only, PETTICOAT and STABILISE). Aortic remodelling was assessed at three aortic levels on follow-up CT. Thirty-day technical/clinical success rates, re-intervention rates and complications were recorded.

RESULTS

A total of 29 patients were included. The median age was 55 years (31-82). The median duration from initial presentation to TEVAR was 7 days (0-84). Intra-procedural complications included one aortic rupture from balloon moulding in a STABILISE case. Thirty-day mortality, stroke, spinal cord ischaemia and visceral ischaemia were 3% (n = 1), 3% (n = 1), 3% (n = 1) and 3% (n = 1), respectively. (All occurred in acute TBAD.) Overall survival was 50.5 months (18-115). Median follow-up was 31 months (1-115). Six patients (21%) required re-intervention, with a median time of 5 months (5-46) from first TEVAR. Overall complete aortic remodelling rates were: 89% at the proximal descending thoracic aorta, 78% at the distal thoracic aorta and 50% at the infra-renal abdominal aorta. At the infra-renal aorta, the STABILISE group (n = 11) had a higher complete aortic remodelling rate (82%) compared to TEVAR alone (n = 12) (20%).

CONCLUSION

Endovascular intervention for acute and subacute TBAD is safe with a high rate of technical success. STABILISE results in higher aortic remodelling at the infra-renal aorta (82%) compared to TEVAR alone (20%) but risks aortic rupture from balloon moulding.

Predictive Factors of Operative Need in Medically Managed Type B Aortic Dissections

BACKGROUND

Aneurysmal degeneration of medically managed type B aortic dissection (TBAD) can be a life-threatening condition. Preventive thoracic endovascular aorta repair (TEVAR) in patients at risk could potentially be beneficial. The aim of this study was to examine the predictors for late aneurysmal dilatation after TBAD.

METHODS

A retrospective study was conducted on 82 patients with medically managed acute TBAD for a minimum of 14 days. Relevant demographic, biochemical, and radiographic variables at presentation were studied. The aortic dissection risk calculator tool developed by Sailer et al., predicting the risk of adverse events after aortic dissection based on demographic and radiographic variables at presentation, was tested retrospectively.

RESULTS

With a median follow-up of 36 months (range 13-68), 25 (30.5%) patients underwent surgery (92% TEVAR). A larger initial aortic and false lumen diameter as well as a greater distal extension of the dissection was associated with higher need for surgery (respectively, P = 0.003, P = 0.004, and P = 0.001). We observed higher growth rates of maximum aortic diameter in patients with a greater distal extension of the dissection, larger false lumen diameters and false lumen outflow, and entry tears located at the inner aortic arch (respectively, P = 0.001, P = 0.005, P = 0.001 and P = 0.014). No significant correlations could be found for the risks provided by the calculator tool.

CONCLUSIONS

The initial maximum aortic diameter of TBAD is a key predictor for aortic growth. Furthermore, the distal extension of the dissection also seems to play an important role in late aneurysmal degeneration. However, we were not able to confirm the added value of the risk calculator tool in our study group.

Acute complicated type B aortic dissection during the New York City COVID-19 surge

The impact of the coronavirus disease 2019 (COVID‐19) pandemic in New York City (NYC) is dramatic. COVID‐19 cases surged, hospitals expanded to meet capacity, and NYC remains the global epicenter of this pandemic. During this unprecedented time, a young woman with known Marfan syndrome presented with an acute complicated type B aortic dissection to our Aortic Center. Using the provisional extension to induce a complete attachment technique, we treated this patient and quickly discharged her the next day to decrease the risk of COVID‐19 infection. Her progress was monitored using frequent phone calls and one office visit at two weeks.

Improved Remodeling With TEVAR and Distal Bare-Metal Stent in Acute Complicated Type B Dissection

BACKGROUND

The ASSIST (A multicentre Study in Survivors of type B aortic dissection undergoing Stenting) study compared both 1-year outcomes and evolution of true and false lumen (eg, remodeling) in patients with complicated type B aortic dissection subjected to thoracic endovascular aortic repair (TEVAR) with distal true lumen scaffolding by self-expanding nitinol open stent in comparison with TEVAR alone.

METHODS

The ASSIST study was a multicenter prospective single-arm study comparing clinical and imaging data from 39 consecutive patients (59.4 ± 13 years of age) who received TEVAR and the JOTEC E-XL open stent with data from matched control subjects treated with TEVAR alone based on 1:1 propensity score matching. Clinical data were collected by an independent Contract Research Organization (CRO) and computed tomography images were subjected to blinded core-lab analysis.

RESULTS

There were no differences in baseline demographics, clinical profiles, morphological data, procedural details, and in-hospital and 1-year outcomes between groups. Differences emerged with regard to evolution of both true lumen distal to stent graft, false lumen over the entire length of dissection, and remodeling (P < .001). At 1 year, TEVAR with the E-XL stent revealed false lumen thrombosis at the level of celiac trunk in 53.8% vs 17.9% with TEVAR alone (P = .004). Kaplan-Meier survival analysis indicated favorable clinical outcomes with the additional E-XL stent.

CONCLUSIONS

TEVAR for acute complicated type B aortic dissection proved to be safe and promoted remodeling of the stent grafted thoracic aorta. Additional scaffolding of the true lumen distal to TEVAR with a self-expanding stent supported distal true lumen expansion, false lumen regression, and thrombosis, with evidence of improved distal remodeling at 1 year.

Long-term Results of Thoracic Endovascular Aortic Repair for Type B Aortic Dissection and Risk Factors for Survival

Purpose: To compare characteristics of acute, subacute, and chronic type B aortic dissection and their influence on long-term results of thoracic endovascular aortic repair (TEVAR). Materials and Methods: In a single-center, retrospective cohort study, 314 patients (median age 52 years; 244 men) with acute (n=165), subacute (n=115), or chronic (n=34) type B aortic dissection underwent TEVAR between January 2009 and December 2013. Patient demographics, risk factors, and imaging characteristics were compared among the groups. Univariable and multivariable Cox regression analyses were performed to identify any factors influencing survival. Results: The acute and subacute patients exhibited more complications at presentation than chronic patients. However, the chronic patients exhibited more aneurysmal dilatation (p<0.001) and true lumen collapse (p<0.001). Over a mean follow-up of 68.1±22.9 months (range 2–108), subacute patients showed a lower reintervention rate (3.6% vs 12.1% vs 12.1%, p=0.045), a lower major complication rate (14.4% vs 33.1% vs 27.3%, p=0.002), and better cumulative overall survival (p=0.03) than the acute and chronic groups, respectively. Furthermore, acute patients developed more stent-graft–induced distal erosion (p=0.017) and retrograde type A dissection (RTAD) (p=0.036), whereas chronic patients had less aortic remodeling in the stented segment (p<0.001), distal thoracic aorta (p<0.001), and abdominal aorta (p=0.047). Finally, multivariable analysis demonstrated age >52 years, visceral malperfusion, and RTAD as independent factors influencing overall survival; aneurysmal dilatation, rupture/impending rupture, and RTAD were independent factors influencing aorta-specific survival. Conclusion: Acute and subacute patients had increased risks of rupture and complications at presentation, whereas chronic patients had increased risks for aneurysmal dilatation. From a long-term perspective, the subacute phase might be an optimal time for TEVAR in cases of type B aortic dissection that do not need emergent interventions. The risk factors influencing survival should be identified, carefully managed, and possibly prevented.

Dynamic Indicators That Impact the Outcomes of Thoracic Endovascular Aortic Repair in Complicated Type B Aortic Dissection

PURPOSE

To investigate dynamic variables obtained from retrospective computed tomography angiography for ability to predict thoracic endovascular aortic repair (TEVAR) outcomes in patients with complicated type B aortic dissection (cTBAD).

MATERIALS AND METHODS

Seventy-nine patients with cTBAD who received TEVAR from March 2009 to June 2018 were retrospectively enrolled. Relative true lumen area (r-TLA) was computed at the level of tracheal bifurcation every 5% of all R-R intervals. Parameters that reflect the state of intimal motion were evaluated, including difference between maximum and minimum r-TLA (D-TLA) and true lumen collapse. The endpoints comprised early (≤ 30 days) and late (> 30 days) outcomes after intervention.

RESULTS

Overall early mortality rate was 13.9% (11/79), and early adverse events rate was 24.1% (19/79). Patients who received TEVAR within 2 days of symptom onset demonstrated the worst outcomes. A longer time of r-TLA < 25% in 1 cardiac cycle (P = .049) and larger D-TLA (P < .001) were correlated to an increased early death. In addition, D-TLA was an independent predictor of early mortality. Area under the curve of D-TLA was 0.849 (95% confidence interval 0.730-0.967) for predicting early mortality and 0.742 (95% CI 0.611-0.873) for predicting early adverse events. Survival and event-free survival rates during follow-up were decreased in the D-TLA > 21.5% group compared with the D-TLA ≤ 21.5% group (all P < .001).

CONCLUSIONS

Larger D-TLA is correlated with worse postoperative outcomes and might be a crucial parameter for future risk stratification in patients with cTBAD.

Society for Vascular Surgery (SVS) and Society of Thoracic Surgeons (STS) Reporting Standards for Type B Aortic Dissections

This Society for Vascular Surgery/Society of Thoracic Surgeons (SVS/STS) document illustrates and defines the overall nomenclature associated with type B aortic dissection. The contents describe a new classification system for practical use and reporting that includes the aortic arch. Chronicity of aortic dissection is also defined along with nomenclature in patients with prior aortic repair and other aortic pathologic processes, such as intramural hematoma and penetrating atherosclerotic ulcer. Complicated vs uncomplicated dissections are clearly defined with a new high-risk grouping that will undoubtedly grow in reporting and controversy. Follow-up criteria are also discussed with nomenclature for false lumen status in addition to measurement criteria and definitions of aortic remodeling. Overall, the document provides a facile framework of language that will allow more granular discussions and reporting of aortic dissection in the future.

Endovascular Therapy for Nonischemic vs Ischemic Complicated Acute Type B Aortic Dissection

Purpose: To report a single-center experience with thoracic endovascular aortic repair (TEVAR) for complicated acute type B aortic dissection (cATBAD) comparing patients with vs without end-organ ischemia. Materials and Methods: Between November 2010 and December 2017, 64 patients (mean age 64.8±12.5 years; 49 men) underwent TEVAR for cATBAD. Patients were grouped into 2 cohorts: nonischemic (39, 61%) patients with unrelenting pain, early progressive aortic dilatation, uncontrolled hypertension, or rupture, and ischemic (25, 39%) patients with visceral, renal, lower extremity, or spinal cord hypoperfusion. Results: Mean time from diagnosis to treatment was 7.5 days (range 1–32) in the nonischemic group vs 2.3 days (range 1–14) days in the ischemic group (p=0.007). Fourteen (56%) of 25 ischemic cATBAD patients had stents implanted in the renovascular branch vessels, while 4 (16%) patients had stents implanted in the iliac arteries. When branch vessel cannulation failed, fenestrations were made in the intimal flap to improve perfusion of the involved branch (n=5). In the nonischemic group, 3 arteries were stented owing to atherosclerotic stenosis. Technical success was achieved in 62 (97%) of 64 patients; despite stenting, 2 patients had low renal artery perfusion on final angiography. There were no statistically significant differences in early or late outcomes between the nonischemic vs ischemic cATBAD patients. Six (9%) patients died within 30 days: 2 (5%) in the nonischemic group vs 4 (16%) in the ischemic group. Major complications (1 stroke, 2 cases of paraplegia, 1 retrograde type A dissection, and 1 case of bowel ischemia) occurred only in the nonischemic group. The mean follow-up was 28 months. Late endoleaks were observed in 3 (8%) nonischemic patients and 1 (4%) ischemic patient. Reinterventions were required in 7 (18%) nonischemic patients and 4 (16%) ischemic patients. Conclusion: TEVAR is an effective and safe method of treating cATBAD. Early intervention in ischemic cATBAD may have played a significant role in the lack of significant difference between ischemic and nonischemic cATBAD outcomes. Direct visceral reperfusion through branch vessel stenting during TEVAR may be crucial in achieving good outcomes in ischemic cATBAD.

Oesophageal necrosis after thoracic endovascular aortic repair: a minimally invasive endovascular approach-a dramatic complication

There are few cases in the literature reporting dysphagia caused by oesophageal compression by the aorta due to acute or chronic aortic pathology. This type of dysphagia is called dysphagia aortica. Thoracic endovascular aortic repair is nowadays the treatment of choice for anatomically suitable patients experiencing complicated Type B aortic dissection. Oesophageal necrosis is a rare but fatal complication following thoracic endovascular aortic repair. Extrinsic oesophageal compression by the thrombosed aneurysmal sac, a mediastinal haematoma or extensive thrombosis in the false lumen of a dissected aorta and acute vascular occlusion of the oesophageal supply are possible mechanisms. When oesophageal necrosis is suspected, endoscopic examination and computed tomography imaging should be performed repeatedly. Oesophagoscopy will confirm the diagnosis revealing a black, diffusely necrotic and ulcerated oesophageal mucosa. It is critical to intervene before full-thickness oesophageal wall necrosis and mediastinitis occur. Guidelines are absent because of the rarity of this complication. Moreover, lack of a large series does not permit the establishment of guidelines either. However, oesophagectomy of the impaired oesophagus is the only chance for survival. Unfortunately, survival rates are disappointing. Prevention and awareness is the cornerstone of success. Early endoscopic examination when oesophageal necrosis is suspected due to even minimal symptoms will detect this fatal menace on time.

Thoracic endovascular aortic repair with stent grafts alone or with a composite device design in patients with acute type B aortic dissection in the setting of malperfusion

OBJECTIVE

The objective of this study was to compare short-term outcomes in patients who underwent thoracic endovascular aortic repair (TEVAR) with stent grafts alone or with a composite device design (stent graft plus bare-metal aortic stent) for acute type B aortic dissection in the setting of malperfusion.

METHODS

This retrospective analysis included patients with acute (≤14 days of symptom onset) complicated type B dissection in the setting of malperfusion who were treated with stent grafts alone (TEVAR cohort) at two European institutions vs those who underwent TEVAR with a composite device design (Cook Medical, Bloomington, Ind) in the investigational STABLE I feasibility study and STABLE II pivotal study (STABLE cohort). Preoperative characteristics and 30-day outcomes (including mortality, malperfusion-related mortality, morbidity, and secondary interventions) were compared between the two groups.

RESULTS

The TEVAR cohort (41 patients; mean age, 58.8 ± 12.7 years; 78.0% male) and the STABLE cohort (84 patients; mean age, 57.8 ± 11.7 years; 71.4% male) were largely similar in preoperative medical characteristics, with more STABLE patients presenting with a history of hypertension (79.8% vs 58.5%; P = .018). The TEVAR and STABLE groups had similar lengths of dissection (451.8 ± 112.7 mm vs 411.8 ± 116.4 mm; P = .10) and similar proximal and distal extent of dissection. At presentation, the two groups exhibited comparable organ system involvement in malperfusion: renal (53.7% TEVAR, 57.1% STABLE), gastrointestinal (41.5% TEVAR, 44.0% STABLE), lower extremities (34.1% TEVAR, 52.4% STABLE), and spinal cord (9.8% TEVAR, 2.4% STABLE). The 30-day rate of all-cause mortality was 17.1% (7/41) in the TEVAR group and 8.3% (7/84) in the STABLE group (P = .22). The 30-day rate of malperfusion-related mortality (deaths from bowel/mesenteric ischemia or multiple organ failure) was 12% (5/41) in the TEVAR group and 2.4% (2/84) in the STABLE group (P = .038). The 30-day morbidity, for the TEVAR and STABLE groups, respectively, included bowel ischemia (9.8% [4/41] vs 2.4% [2/84]; P = .09), renal failure requiring dialysis (7.3% [3/41] vs 9.5% [8/84]; P > .99), paraplegia or paraparesis (4.9% [2/41] vs 3.6% [3/84]; P = .66), and stroke (2.4% [1/41] vs 10.7% [9/84]; P = .16). The occurrence of 30-day secondary intervention was similar in the TEVAR and STABLE groups (7.3% [3/41] vs 7.1% [6/84]; P > .99). True lumen expansion in the abdominal aorta was significantly greater in the STABLE group.

CONCLUSIONS

In patients with acute type B aortic dissection in the setting of branch vessel malperfusion, the use of a composite device with proximal stent grafts and distal bare aortic stent appeared to result in lower malperfusion-related mortality than the use of stent grafts alone. The 30-day rates of morbidity and secondary interventions were similar between the groups.

The top 100 manuscripts in emergency cardiac surgery. Potential role in cardiothoracic training. A bibliometric analysis

Background

Emergency Cardiac Surgery (ECS) is a component of cardiothoracic training. Citations are considered to represent a papers influence. Bibliometric analyses allow us to identify the most influential work, and future research. We aim to highlight the key research themes within ECS and determine their potential impact on cardiothoracic training.

Methods

Thomas Reuters Web of Science was searched using terms [Emergency AND Card* AND Surg*]. Results were ranked by citation and reviewed by a panel of cardiac surgeons to identify the top 100 cited papers relevant to ECS. Papers were analysed by topic, journal and impact. Regression analysis was used to determine a link between impact factor and scientific impact.

Results

3823 papers were identified. Median citations for the top 100 was 88. The paper with the highest impact was by Nashef et al. focusing on the use of EuroSCORE (2043 citations). The Annals of Thoracic Surgery published most papers (n = 18:1778 citations). The European Journal of Cardiothoracic Surgery coveted the most citations (n = 2649). The USA published most papers (n = 55).The most ubiquitous topics were; risk stratification, circulatory support and aortic surgery. A positive relationship between journal impact fact and the scientific impact of manuscripts in ECS (P = 0.043) was deduced.

Conclusion

This study is the first of its kind and identified the papers which are likely to the contribute most to training and understanding of ECS. A papers influence is partially determined by journal impact factor. Bibliometric analysis is a potent tool to identify surgical training needs.

In Vivo Assessment of Ascending and Arch Aortic Compliance

BACKGROUND

Dynamic compliance (Cd) of the adult thoracic ascending and arch aorta has had limited in vivo evaluation in patients with aortic disease. This study evaluates aortic compliance using intravascular ultrasound (IVUS) across a range of thoracic aortic diseases.

METHODS

Seventy-nine patients undergoing thoracic aortic endovascular procedures had Cd measurements of the ascending aorta proximal to the origin of the brachiocephalic trunk and distal to the origin of the left common carotid artery using IVUS before endograft deployment. Cd was calculated for each segment using the following equation, Cd = ΔD/(D • ΔP) where ΔD = change in aortic diameter, D = diameter in diastole, and ΔP = pulse pressure.

RESULTS

Mean Cd of the ascending aorta in all patients (18.4%/mm Hg) and aortic arch (16.5 %/100 mm Hg) did not differ significantly. Compliance was significantly lower in patients being treated for thoracic aortic aneurysm and penetrating ulcer than in patients with traumatic rupture, acute and chronic dissection (P = 0.009). Compliance was significantly higher in patients with aortic transection compared with thoracic aneurysm or penetrating ulcer (P = 0.001). Compliance decreased with age by 0.44 ± 0.06 (P = 0.001) per year in the ascending aorta and 0.41 ± 0.05 (P = 0.001) per year in the aortic arch. Compliance did not increase with diameter when adjusted for age (P = 0.65). Compliance measured in the ascending aorta in 7 patients after descending thoracic aortic endograft repair decreased to 12.6%/100 mm Hg, although not significant (P = 0.18).

CONCLUSIONS

Ascending and aortic arch compliance is significantly higher than reported for peripheral vessels. Thoracic aortic compliance decreases with age and is not related to aortic diameter. The results of the present study are important when considering the development of endoprosthesis devices and long-term effects on the thoracic aorta.

Duplex Ultrasound Assessment and Outcomes of Renal Malperfusion Syndromes after Acute Aortic Dissection

BACKGROUND

We investigated the feasibility of renal duplex ultrasound in the identification of renal malperfusion in acute aortic dissection and evaluated whether intervention for renal malperfusion improved outcomes over best medical management alone.

METHODS

All patients with acute aortic dissections involving the renovisceral aorta who underwent a duplex ultrasound were included (2004-2016). We assessed duplex findings among patients who developed acute kidney injury (AKI; 50% increase in serum creatinine) and compared AKI, 30-day mortality, and overall survival among patients who underwent a procedure to treat malperfusion versus those who did not.

RESULTS

Of 37 patients with acute dissection involving the renovisceral aorta (73% were male, 59% had type B dissection, mean follow-up 4.6 ± 0.6 years), 70% developed AKI, 11% required dialysis, and 5% developed permanent dialysis dependence. AKI was correlated with higher peak creatinine levels (4.2 vs. 2.2 mg/dL, P < 0.001), although 30-day mortality and overall survival were similar (both, P ≥ 0.24). Progression to AKI was associated with significantly lower end-diastolic velocity (EDV) measurements on renal duplex (17 vs. 27 cm/sec, P = 0.03); an EDV threshold of 23 cm/sec had a positive predictive value of 85% for AKI. Operative intervention (n = 10) was associated with lower follow-up creatinine (0.9 vs. 2.1 mg/dL, P = 0.002), although there was no difference in progression to dialysis dependence, 30-day mortality, or overall survival (all, P ≥ 0.34).

CONCLUSIONS

Patients who developed AKI demonstrated characteristic renal duplex ultrasound findings with lower EDV measurements in the distal renal arteries bilaterally. Performing a renal malperfusion procedure was associated with normalization of postoperative creatinine without affecting 30-day mortality or overall survival.

Endovascular management of acute aortic dissection

Acute dissection of the thoracic aorta is a potentially life-threatening condition which requires collaborative treatment from multiple specialties for optimal patient outcomes. Dissections involving the ascending aorta and aortic arch have traditionally been managed entirely by surgery, while dissections beyond the arch vessels have most commonly been relegated to medical management. This algorithm has been undergoing a paradigm shift over the past two decades due to improvements in stent graft technology, better understanding of the hemodynamic interactions of the true and false lumen and their influence on organ and limb perfusion, and improvements in medical management and long term surveillance for dissection-related complications. This manuscript includes a brief discussion of the pathogenesis and etiology of dissection, followed by an in-depth review of the medical and endovascular techniques utilized to treat patients afflicted by this condition.

Guidelines for the management of thoracic aortic disease in 2017

This review provides a general overview of the consensus statement from the 2010 more recent updates AHA/ACC Guidelines for the Diagnosis and Management of Patients with Thoracic Aortic Disease, and highlights current practice patterns. The suggestions herein are intended to facilitate clinical decision making in the management of thoracic aortic disease. The main intent of this report is to highlight screening, surveillance, initial and definitive management of thoracic aortic disease, and special populations that should be considered.

Endovascular management of chronic symptomatic aortic dissection with the Streamliner Multilayer Flow Modulator: Twelve-month outcomes from the global registry

OBJECTIVE

Reported are initial 12-month outcomes of patients with chronic symptomatic aortic dissection managed by the Streamliner Multilayer Flow Modulator (SMFM; Cardiatis, Isnes, Belgium). Primary end points were freedom from rupture- and aortic-related death, and reduction in false lumen index. Secondary end points were patency of great vessels and visceral branches, and freedom of stroke, paraplegia, and renal failure.

METHODS

Out of 876 SMFM implanted globally, we have knowledge of 542. To date, 312 patients are maintained in the global registry, of which 38 patients were identified as having an aortic dissection (12.2%). Indications included 35 Stanford type B dissections, two Stanford type A and B dissections, and one mycotic Stanford type B dissection.

RESULTS

There were no reported ruptures or aortic-related deaths. All cause survival was 85.3% Twelve-month freedom from neurologic events was 100%, and there were no incidences of end-organ ischemia, paraplegia or renal insult. Morphologic analysis exhibited dissection remodeling by a reduction in longitudinal length of the dissected aorta, and false lumen volume. A statistically significant reduction in false lumen index (P = .016) at 12 months, and a borderline significant increase in true lumen volume (P = .053) confirmed dissection remodeling.

CONCLUSIONS

The SMFM is an option in management of complex pan-aortic dissection. Results highlight SMFM implantation leads to dissection stabilization with no further aneurysm progression, and no retrograde type A dissection. Thoracic endovascular aneurysm repair by SMFM ensued in freedom from aortic rupture, neurologic stroke, paraplegia and renal failure. Further analysis of the global registry data will inform long-term outcomes.

Role of molecular imaging with positron emission tomographic in aortic aneurysms

Aortic aneurysms (AA) are often asymptomatic before the occurrence of acute, potentially fatal complications including dissection and/or rupture. Beyond aortic size, the ability to assess aortic wall characteristics and processes contributing to aneurysm development may allow improved selection of patients who may benefit from prophylactic surgical intervention. Current risk stratification for aneurysms relies upon routine noninvasive imaging of aortic size without assessing the underlying pathophysiologic processes, including features such as inflammation, which may be associated with aneurysm development and progression. The use of molecular imaging modalities with positron emission tomographic (PET) scan allows characterization of aortic wall inflammatory activity. Elevated uptake of Fuorine-2-deoxy-D-glucose (FDG), a radiotracer with elevated avidity in highly-metabolic cells, has been correlated with the development and progression of both abdominal and thoracic AA in a number of animal models and clinical studies. Other novel PET radiotracers targeting matrix metalloproteinases (MMPs), mitochondrial translocator proteins (TSPO) and endothelial cell adhesion molecules are being investigated for clinical utility in identifying progression of disease in AA. By further defining the activation of molecular pathways in assessing aortic regions at risk for dilatation, this imaging modality can be integrated into future clinical decision-making models.

Effects of Gender Differences on Short-term Outcomes in Patients with Type B Aortic Dissection

BACKGROUND

Gender-related differences in type B aortic dissection (TBAD) presentation and outcomes are not well understood. The objective of this study is to assess the impact of gender on short-term outcomes in patients with TBAD.

METHODS

Patients with TBAD were identified from the National Inpatient Sample datasets from 2009 to 2012 according to previously published methods. The primary outcomes of interest were in-hospital mortality and major complications (renal, cardiac, pulmonary, paraplegia, and stroke related) between men and women. An inverse propensity-weighted regression was used to balance comorbid and clinical presentation differences. Subgroup analyses were performed on those undergoing endovascular (thoracic endovascular aortic repair [TEVAR]) and open repair, and for elderly patients over the age of 70.

RESULTS

We identified 9855 patients with TBAD; women were fewer (43.6%, n = 4293) and presented at a later age (69.8 ± 15.5 vs. 62.8 ± 15.6, P < 0.001). Women had more comorbidities (median Elixhauser 4 [interquartile range, IQR 2-5] vs. 3 [IQR 2-5], P < 0.001) and were more often managed nonoperatively (87.4% vs. 81.8%, P < 0.001) compared with men. For those undergoing intervention, 58% (n = 903) had open repair and TEVAR rates were higher in women compared with men (45.6% vs. 40.0%, P < 0.001). Unadjusted mortality rates did not differ significantly by gender (male: 11.6% vs. female: 10.7%). In an adjusted propensity-weighted regression, gender did not significantly affect in-hospital mortality or stroke rates, but women were less likely to have acute renal failure during their hospitalization and more likely to experience cardiac events when undergoing open repair. Elderly women were also less likely to experience acute renal failure but had higher odds of cardiac events regardless of intervention compared with elderly men.

CONCLUSIONS

In comparison with men, women with TBAD presented at a later age, were more likely to undergo TEVAR, sustain a perioperative cardiac event with open surgery, and were less likely to experience acute renal complications overall. Elderly women were additionally more likely to sustain a cardiac event regardless of operative status. Future studies should attempt to identify anatomic and epidemiologic reasons for these differences.

Aneurysmal Degeneration in Patients with Type B Aortic Dissection

BACKGROUND

The optimal management of type B aortic dissection (TBAD) remains controversial in the era of endovascular therapies. This study reports the outcomes and complication rates of different treatment paradigms for TBAD.

METHODS

A retrospective review was undertaken of all patients with TBAD from June 2006 to June 2012. Demographics, hospital course, and follow-up visits were analyzed. Patients who underwent surgical interventions were compared to those with medical therapy. Survival rates and predictors of outcome were determined using the Kaplan-Meier method with Cox proportional hazards.

RESULTS

Of 261 consecutive patients who were hospitalized during this period with a confirmed thoracic dissection, 134 (51%) had TBAD. Sixty-two (46%) were women, and the mean age was 66.4 ± 14.9. Median follow-up was 22.4 (0, 184) months. Thirty-five patients underwent surgical intervention with 20 thoracic endovascular aortic repair (TEVAR) and open surgery in 15. The overall 30-day mortality was 7%, and cumulative survival rates at 1, 3, and 5 years were 85% (95% confidence interval [CI], 79-91), 68% (95% CI, 59-78), and 57% (95% CI, 47-69) with no difference between medical versus surgical groups (P = 0.8) and TEVAR versus open surgery group (P = 1.0). Sixty-six (50%) patients developed aneurysmal expansion, which required surgical intervention in 26 (hazard ratios [HR], 0.99; P = 0.96). Malperfusion and rupture only occurred in 5 (HR, 1.57; P = 0.54) and 5 (HR, 3.64; P = 0.01) patients, respectively. Multivariate analysis for overall survival found renal insufficiency (HR, 2.6; P = 0.004) and age (HR, 1.06; P < 0.0001) and rupture (HR 3.3, P = 0.04) were independent predictors of mortality. Intramural hematoma was not a significant predictor of survival (HR, 0.49; P = 0.11).

CONCLUSIONS

Medical therapy remains the mainstay of treating TBAD with low morbidity. Surgical interventions are indicated in selected patients with malperfusion or aneurysmal expansion with comparable survival rates.

Diagnosis and treatment of uncomplicated type B aortic dissection

A type B dissection involves the aorta distal to the subclavian artery, and accounts for 25–40% of aortic dissections. Approximately 75% of these are uncomplicated with no malperfusion or ischemia. Multiple consensus statements recommend thoracic endovascular aortic repair (TEVAR) as the treatment of choice for acute complicated type B aortic dissections, while uncomplicated type B dissections are traditionally treated with medical management alone, including strict blood pressure control, as open repairs have a prohibitively high morbidity of up to 31%. However, with medical treatment alone, the morbidity, including aneurysm degeneration of the affected segment, is 30%, and mortality is 10% over 5 years. For both chronic and acute uncomplicated type B aortic dissections, emerging evidence supports the use of both best medical therapy and TEVAR. This paper reviews the current diagnosis and treatment of uncomplicated type B aortic dissections.