Outcomes of Medical Management of Acute Type B Aortic Dissection

Intense impact of IL-1β expressing inflammatory macrophages in acute aortic dissection

There is no treatment for acute aortic dissection (AAD) targeting inflammatory cells. We aimed to identify the new therapeutic targets associated with inflammatory cells. We characterized the specific distribution of myeloid cells of both human type A AAD samples and a murine AAD model generated using angiotensin II (ANGII) and β-aminopropionitrile (BAPN) by single-cell RNA sequencing (scRNA-seq). We also examined the effect of an anti-interleukin-1β (IL-1β) antibody in the murine AAD model. IL1B+ inflammatory macrophages and classical monocytes were increased in human AAD samples. Trajectory analysis demonstrated that IL1B+ inflammatory macrophages differentiated from S100A8/9/12+ classical monocytes uniquely observed in the aorta of AAD. We found increased infiltration of neutrophils and monocytes with the expression of inflammatory cytokines in the aorta and accumulation of inflammatory macrophages before the onset of macroscopic AAD in the murine AAD model. In blocking experiments using an anti-IL-1β antibody, it improved survival of murine AAD model by preventing elastin degradation. We observed the accumulation of inflammatory macrophages expressing IL-1β in both human AAD samples and in a murine AAD model. Anti-IL-1β antibody could improve the mortality rate in mice, suggesting that it may be a treatment option for AAD.

Trends in the incidence, surgical management and outcomes of type B aortic dissections in Australia over the last decade

OBJECTIVES

This study aims to investigate the incidence and in-hospital outcomes of surgical repair for type B aortic dissection (TBAD) in Australia.

METHODS

Data were obtained from the Australasian Vascular Audit (AVA) and the Australian Institute of Health and Welfare (AIHW). The former is a total practice audit mandated for all members of the Australian and New Zealand Society for Vascular Surgery (ANZSVS) while the latter is an independent government agency which records all healthcare data in Australia. All cases of TBAD which underwent surgical intervention (endovascular or open repair) between 2010 and 2019 were identified using prospectively recorded data from the AVA (New Zealand data was excluded). The primary outcomes were temporal trends in procedures and hospital mortality; secondary outcomes were complications and risk factors for mortality. All admissions and procedures for, and hospital deaths from, TBAD in Australia were identified in AIHW datasets using the relevant diagnosis and procedure codes, with age-standardized rates calculated for the period 2000-01 to 2018-19.

RESULTS

A total of 567 cases of TBAD underwent vascular surgical intervention (AVA data, Australia). Of these, 96.3% were treated by endovascular repair. There was an increase in the annual procedure number from 45 in 2010 to 88 in 2019. In-hospital mortality was 4.8% for endovascular repair and 19% for open repair (p = 0.021). From 2000-01 to 2018-19, the age-standardized procedure rates for TBAD (Australia) doubled, the proportion of admitted patients undergoing a procedure rose from 28% to 43%, and in-hospital deaths fell by 25%.

CONCLUSION

There has been an increasing incidence of vascular surgical intervention for TBAD in Australia. The majority of patients received endovascular therapy while the mortality from surgically managed TBAD appears to be falling.

Prognostic impact of oral anticoagulation therapy and atrial fibrillation in patients with type B acute aortic dissection

Background

The prognostic impact of atrial fibrillation (AF) and oral anticoagulation (OAC) therapy in patients with type B acute aortic dissection (AAD) remains unclear. Therefore, we investigated the prognostic impact of AF and OAC therapy in patients with type B AAD.

Methods

Consecutive patients diagnosed with AAD were included in this single-center, retrospective study. Patients with type B AAD were selected from the study population and divided into three groups: AF(+)/OAC(+), AF(+)/OAC(-), and AF(-)/OAC(-). The primary end point was major adverse cardiovascular and cerebrovascular events (MACCE), including all-cause death, progressive aortic events, cerebral infarction, and organ malperfusion.

Results

In total, 139 patients diagnosed with type B AAD were analyzed. AF was observed in 27 patients (19%). Among them, 13 patients (9%) received OAC therapy for AF. MACCE occurred in 32 patients (23%) during the observation period: all-cause death in four patients, progressive aortic events in 24 patients, cerebral infarction events in two patients, and malperfusion events in two patients. The incidence of MACCE was higher in the AF(+)/OAC(+) group than in the AF(+)/OAC(-) group (hazard ratio[HR]: 3.875; 95% confidence interval [CI]: 1.153-17.496). In contrast, there was no significant difference in the incidence of MACCE between the AF(+)/OAC(-) and AF(-)/OAC(-) groups (HR: 1.001, 95% CI: 0.509-1.802).

Conclusion

Among patients with type B AAD, the use of OAC for AF was associated with a higher risk of MACCE.

Rosuvastatin, but not atorvastatin, enhances the antihypertensive effect of cilostazol in an acute model of hypertension

PURPOSE

Hypertensive emergency, a sudden and severe increase in blood pressure, necessitates immediate intervention to avoid end-organ damage. Cilostazol, a selective phosphodiesterase-III inhibitor, has vasodilator effect. Here, we investigated the effect of two commonly used statins, atorvastatin or rosuvastatin, on cilostazol antihypertensive activity in acute model of hypertension.

METHODS

Hypertensive emergency was induced via angiotensin II intravenous infusion (120 ng.kg-1.min-1). Rats were subjected to real-time arterial hemodynamics and electrocardiogram recording while investigated drugs were injected slowly at cumulative doses 0.5, 1, and 2 mg.kg-1, individually or in combination, followed by baroreflex sensitivity (BRS) analysis and serum electrolytes (Na+ and K+) and vasomodulators (norepinephrine (NE), and nitric oxide (NO)) assessment.

RESULTS

Cilostazol reduced systolic blood pressure (SBP), while co-injection with rosuvastatin augmented cilostazol SBP-reduction up to 30 mmHg. Compared to atorvastatin, rosuvastatin boosted the cilostazol-associated reduction in peripheral resistance, as evidenced by further decrease in diastolic, pulse, and dicrotic-notch pressures. Rosuvastatin co-injection prevented cilostazol-induced changes of ejection and non-ejection durations. Additionally, rosuvastatin coadministration produced better restoration of BRS, with an observed augmented increase in BRS indexes from spectral analysis. Greater reduction in sympathetic/parasympathetic ratio and serum NE upon rosuvastatin coadministration indicates further shift in sympathovagal balance towards parasympathetic dominance. Additionally, rosuvastatin coinjection caused a greater decrease in serum sodium, while more increase in NO indicating augmented reduction of extracellular volume and endothelial dysfunction.

CONCLUSION

Rosuvastatin boosted cilostazol's antihypertensive actions through effects on peripheral resistance, BRS, sympathovagal balance, endothelial dysfunction, and electrolytes balance, while atorvastatin did not demonstrate a comparable impact.

A rare case of an acute type B aortic dissection contained infrarenal rupture of the false lumen after prior endovascular abdominal aneurysm repair

New-onset acute type B aortic dissection after prior endovascular aneurysm repair is extremely rare. Extension of an aortic dissection can cause destabilization of the previously implanted stent graft, thrombosis of the stent graft, and rupture of the aneurysmal sac, with high mortality without therapy. This report describes the case of a 66-year-old patient complaining of sudden abdominal pain radiating to both flanks. Computed tomography angiography of the aorta revealed acute type B aortic dissection with infrarenal rupture of the false lumen after endovascular abdominal aneurysm repair 5 years prior. The patient underwent infrarenal open surgical conversion with suprarenal aortic clamping and implantation of a bifurcated Dacron graft. Postoperatively, no serious complications resulted from the treatment, except for fascial dehiscence. In such cases, the patients can be treated in an emergency situation with open repair, despite the high risk of complications and mortality.

Non-A Non-B Acute Aortic Dissection: Is There Some Confusion in the Radiologist's Mind?

BACKGROUND

The aim of this study is to define and determine the rate of acute non-A-non-B aortic dissections, and to evaluate CT angiography findings and possible complications, as well as to discuss management strategies and currently available therapy. Non-A non-B type of aortic dissection is still a grey area in the radiologist's mind, such that it is not entirely clear what should be reported and completed in terms of this disease.

METHODS

A retrospective single-center study including 36 pre-treatment CT angiograms of consecutive patients (mean age: 61 years) between January 2012 and December 2022 with aortic dissection involving the aortic arch with/without the thoracic descending/abdominal aorta (type non-A non-B).

RESULTS

According to the dissection anatomy, we identified three modalities of spontaneous acute non-A-non-B anatomical configurations. Configuration 1 (n = 25) with descending-entry tear and retrograde arch extension (DTA entry). Configuration 2 (n = 4) with Arch entry tear and isolated arch involvement (Arch alone). Configuration 3 (n = 7) with Arch entry and anterograde descending (±abdominal) aorta involvement (Arch entry). CT angiogram findings, management, and treatment options are described.

CONCLUSIONS

Acute non-A non-B dissection represents an infrequent occurrence of aortic arch dissection (with or without involvement of the descending aorta) that does not extend to the ascending aorta. The complete understanding of its natural progression, distinct CT angiography subtypes, optimal management, and treatment strategies remains incomplete. Within our series, patients frequently exhibit a complex clinical course, often necessitating a more assertive approach to treatment compared to type B dissections.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Spontaneous Recovery of Paraplegia in a Polytrauma Patient following Spinal Cord Ischemia due to Type B Traumatic Aortic Dissection

Aortic dissection is a life-threatening acute condition characterized by the separation of the aortic wall's layers. It is caused by a tear in the internal vascular wall (intimal layer and middle layer), which results in bleeding between the layers and causes abrupt and excruciating pain. The appropriate consideration must be given to the condition's dynamic nature, and variations in clinical presentation, without neglecting the urgency for intervention. In this case study, a 65-year-old male engaged in a car accident is admitted to urgent care with a traumatic aortic dissection diagnosis that included the aortic arch, a segmental exposed fracture of 1/3 distal of the right femur AO 32C3k, and an intertrochanteric fracture AO 31A1.3. The patient developed transient paraplegia as the initial manifestation of acute aortic dissection, which represents a high mortality and morbidity entity without adequate and prompt treatment, and prompt diagnosis and management were critical. A patient with severe thoracic and abdominal trauma caused by high-energy injury should be properly evaluated for the possibility of traumatic aortic dissection. The endovascular aortic repair was performed, resulting in a positive clinical evolution due to the important participation of the multidisciplinary trauma team involved in patient management and prompted decision-making.

Thoracic Aortic Aneurysms and Arch Disease

Aortic arch and descending thoracic pathology have historically remained in the realm of open surgical repair. Technology is quickly pushing to bring these under the endovascular umbrella, with lower morbidity repairs proving safe in their early experience. Much work remains particularly for acute aortic syndromes, however, to understand who is best treated medically, surgically, endovascularly, or with hybrid approaches.

Hinokitiol for hypertensive emergencies: effects on peripheral resistance, cardiac load, baroreflex sensitivity, and electrolytes balance

Hinokitiol, a natural monoterpenoid, has been shown previously to possess a potent vasodilating activity in vitro in both control and hypertensive aortae. Here, the antihypertensive and cardioprotective effects of an intravenous hinokitiol injection were fully investigated in angiotensin II-induced hypertensive emergency in rats. Hinokitiol intravenous injection was prepared in the form of self-nanoemulsifying drug delivery system. Rat's arterial and ventricular hemodynamics were measured in real-time recordings in addition to surface electrocardiogram while slow injection of cumulative doses of hinokitiol or vehicle as well as time control. Hinokitiol at dose 10 mg/kg showed a considerable reduction in the raised systolic blood pressure (30 mmHg) within only 30 min. The decrease in blood pressure seems to be mediated through a reduction in peripheral resistance, as appears from the decreases in diastolic pressure, dicrotic notch pressure, and pulse pressure. In addition, hinokitiol injection reduced heart load due to the decrease in heart rate, increases in cycle duration (particularly the non-ejection duration) and diastolic duration, and decreases in end-diastolic pressure. An effect most likely mediated via prolongation of ventricular repolarization as appears from the increases in PR, QTc, and JT intervals. However, acute intravenous injection of hinokitiol neither affected the baroreflex sensitivity nor sodium/potassium balance. In conclusion, acute hinokitiol intravenous injection markedly reduced severe hypertension in rats. This effect seems to be mediated through decreasing peripheral resistance and decreasing cardiac load, suggesting that it is an effective treatment in hypertensive emergencies after clinical evaluation.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Procedure and Aortic Remodeling Effects of Entry Closure with Stentgraft for Type B Aortic Dissection: Comparison between the Patients with Narrow True Lumen and Those with Aneurysmal Dilated False Lumen

Objectives: Appropriateness of device selection, procedure protocol and aortic remodeling effects of entry closure (TEVAR) with stent-graft (SG) for patent false lumen type B aortic dissection (TBAD) were compared between the patients with narrow true lumen (narrow group) and those with aneurysmal dilated false lumen (aneurysmal group).

Methods: Twenty-six patients with narrow true lumen (narrow group) and 20 patients with aneurysmal false lumen (aneurysmal group) were included in this study. In narrow group, straight SG was implanted from Zone 3 regardless the distance between the left subclavian artery and entry. In aneurysmal group, straight or taped SG was implanted with proximal landing zone length 20 mm or more. Thoracic aortic anatomy was evaluated by CT and aortic remodeling was defined as true lumen diameter ≥50% of the aortic diameter and occlusion of false lumen. Aorta related death, retrograde type A aortic dissection (RTAD), stentgraft induced new entry (SINE) and aortic maximum diameter enlargement 5 mm or more (aortic expansion) were included in the aortic event.

Results: There was no procedure related complication in narrow group and 1 patient died due to aortic rupture in aneurysmal group, Type Ia endoleak by enhanced CT 7 days after TEVAR was detected in one patient in each group. Achievement of aortic remodeling was significantly better in narrow group. Aortic event occurred in only one patient in narrow group, in whom aortic expansion was observed. In aneurysmal group, aortic event occurred 12 patients (60%) and 2 RTAD, 5 SINE, and 8 aorta expansion were observed. Aortic event free rate was significantly better in narrow group.

Conclusion: TEVAR procedure for the TBAD patients with narrow true lumen seemed to be appropriate, however, different TEVAR procedure or additional procedures would be required for those with aneurysmal dilated false lumen to obtain favorable outcomes. (This is secondary publication from Jpn J Vasc Surg 2021; 30: 347–357.)

Medically Managed Type A Thoracic Intramural Hematoma and Penetrating Aortic Ulcer

Intramural hematoma (IMH) and a penetrating aortic ulcer (PAU) are included in a larger category of disorders termed acute aortic syndromes. These disorders typically involve the thoracic aorta, abdominal aorta, or both, and often require emergent evaluation and treatment. Both IMH and PAU, much like aortic dissection, are classified using the Stanford and DeBakey systems to indicate the aortic area involved, with Stanford type A (DeBakey type I and II) necessitating surgical intervention, and Stanford type B sufficing with medical management of blood pressure. While IMH and PAU share many characteristics of aortic dissection in terms of diagnosis and initial management, there is much controversy surrounding ultimate treatment. In this report, we describe a case of a Stanford type A IMH with associated PAU that was managed medically with a good outcome.

Evaluation of a Standardized Protocol for Medical Management of Uncomplicated Acute Type B Aortic Dissection

OBJECTIVES

The goals of medical management for uncomplicated acute type B aortic dissection are to prevent expansion of the false lumen and malperfusion syndrome. This is accomplished with antihypertensive agents, but medication selection and titration are typically provider dependent. Given the paucity of data on evidence-based management of this population, we hypothesized that a standardized type B aortic dissection medical management protocol would reduce resource utilization and costs, without compromising patient outcomes.

METHODS

A multidisciplinary team developed a goal-directed protocol to standardize the medical management of uncomplicated acute type B aortic dissection, with an emphasis on early initiation of oral medications, weaning of anti-hypertensive infusions and frequent assessment for de-escalation of care. Implementation was in April 2018. A retrospective review of acute type B aortic dissection patients presenting to our institution from April 2016- April 2020 was performed. Patients requiring aortic or peripheral intervention were excluded. Included patients were analyzed based on treatment before or after protocol implementation. Patient demographics, systolic blood pressure, presence of acute kidney injury at presentation, length of stay, cost metrics, and 30-day mortality were compared.

RESULTS

39 patients were included, 21 pre- and 18 post-protocol implementation. Baseline demographics, systolic blood pressure, and presence of acute kidney injury at presentation were similar between the groups. Post-protocol patients had shorter total (8.6 vs 5.5 days, p=.02) and intensive care unit (3.2 vs 1.8 days, p=.002) length of stay. The protocol was associated with significantly decreased total hospital ($38,928 vs $28,066, p=.04), total variable ($23,115 vs $15,627, p=0.02), and pharmacy ($5,094 vs $1,181, p<.001) costs, while inpatient care costs ($15,152 vs $11,467, p=.09) trended down. Post-protocol patients required fewer oral antihypertensive agents at discharge (3.8 vs 2.7, p=.005). No significant difference in 30-day mortality was observed.

CONCLUSIONS

A goal directed protocol reduces resource utilization and costs without compromising early mortality rates for patients with uncomplicated acute type B aortic dissection. Such a strategy may have broader application in medical management of acute aortic syndromes.

Aortic Visceral Segment Instability is evident following Thoracic Endovascular Aortic Repair for Acute and Subacute Type B Aortic Dissection

BACKGROUND

Anatomic remodeling within the thoracic aorta following thoracic endovascular aortic repair (TEVAR) for type B aortic dissections (TBAD) has been well documented, but less is known about the response of the untreated visceral aorta. This study aims to investigate visceral aortic behavior following TEVAR for acute or subacute TBAD and identify associations with clinical outcomes.

METHODS

A multi-center retrospective review was performed of all imaging for all patients treated with TEVAR for acute (0-14 days) and subacute (14-90 days) non-traumatic TBAD between 2006-2020. Cohort was inclusive of uncomplicated, high-risk, and complicated (defined per SVS reporting guidelines) dissections. Centerline aortic measurements of the true and false lumen and total aortic diameter (TAD) were taken at standardized locations relative to aortic anatomy within each aortic zone (zones defined by SVS reporting guidelines). Diameter changes over time were evaluated using repeated measures mixed effects linear growth modeling. Visceral segment instability (VSI) was defined as any growth in TAD ≥ 5mm within aortic zones 5 through 9.

RESULTS

A total of 82 patients were identified. Median length of imaging follow-up was 2.1 years (IQR 3.9 years), with 15% of the cohort having follow-up longer than 5 years. VSI was present in 55% of the cohort, with an average maximal increase in TAD of 10.4±6.3 mm over a median follow-up of 2.1 years (IQR 3.9 years). Roughly a third of the cohort experienced rapid VSI (growth ≥5mm in first year), and 4.8% of the cohort developed a large para-visceral aneurysm aortic (TAD≥5cm) secondary to VSI. Linear growth modeling identified significant predictable growth in TAD across all visceral zones. Zones 7 had the highest rate of TAD dilation, with a fixed effect estimated rate of 1.3 mm per year (95%-CI 0.23-2.1, p=0.022). The preoperative factor most strongly associated with VSI was ≥6 cumulative number of zones dissected (OR 6.4, 95% OR 1.07-8.6, p=0.041). Odds for aortic reintervention were significantly increased in cases where VSI led to development of a para-visceral aortic aneurysm ≥5cm development (OR 3.7, 95%-CI 1.1-13, p=0.038).

CONCLUSION

VSI was identified in the majority of patients treated with TEVAR for management of acute and subacute TBAD. Preoperative anatomic features such as extent of dissection, rather than procedural details of graft coverage, may play a more significant role in VSI occurrence. Importantly, significant TAD growth occurred in all visceral segments. These results highlight the importance of lifelong surveillance following TEVAR, and identify a subset of patients that may be at increased risk for re-intervention.

Pleural effusion: a potential surrogate marker for higher-risk patients with acute type B aortic dissections

OBJECTIVES

Pleural effusions (PEffs) are known to occur in type B acute aortic dissection (TBAAD). We investigated the relationship between pleural effusion and the development of early or late complications following TBAAD.

METHODS

The incidence of PEff (defined as at least an obliteration of the costophrenic angle in a frontal projection) diagnosed on their initial chest X-ray in patients with TBAAD enrolled in the International Registry of Acute Aortic Dissection was examined. We analysed in-hospital outcomes and long-term survival separately for patients with and without PEffs (PEff+ versus PEff-, respectively).

RESULTS

Included were 1252 patients with TBAAD, of whom 224 (17.9%) had PEff. Compared with patients without PEff in the initial chest X-ray, these were significantly older [mean age 67 (SD: 14.7) vs 63.4 (SD: 14.2) years, P = 0.001] and more often female (42.4% vs 34.2%, P = 0.021) and had more comorbidities (known aortic aneurysm, chronic obstructive pulmonary disease, chronic renal failure, diabetes, congestive heart failure or mitral valve disease). PEff was associated with higher in-hospital mortality (16.1% vs 9.1%, P = 0.002) and increased rates of neurological complications (16.6% vs 11.1%, P = 0.029), acute renal failure (27.2% vs 19.7%, P = 0.017) and hypotension (17.4% vs 9.6%, P = 0.001). In addition, patients with PEff underwent aortic repair more frequently (44.6% vs 32.5%, P < 0.001). In the long-term patients with PEff showed lower 5-year post-discharge survival (67.6% vs 77.6%, P = 0.004). Multivariable analysis with propensity-matched data showed that PEff was not an independent risk factor for in-hospital mortality (odds ratio 1.9, 95% CI 0.8-4.4, P = 0.141).

CONCLUSIONS

Patients with TBAAD and evidence of PEff showed a higher in-hospital mortality, are more likely to develop additional in-hospital complications and have a decreased likelihood of survival during follow-up. However, according to propensity-matched analysis, PEff remained not as an independent predictor of worse outcome but might serve as an early surrogate marker to identify higher-risk patients.

Endovascular therapies for Type B Aortic Dissection

Aortic dissection is a life-threatening condition resulting from a tear in the intimal layer of the aorta, requiring emergent diagnosis and prompt multi-disciplinary management strategy for best patient outcomes. While type A dissection involving ascending aorta is best managed surgically due to high early mortality, type B aortic dissection (TBAD) involving descending aorta generally has better outcomes with conservative management and medical therapy as primary strategy is favored. However, there has been a recent paradigm shift in management of TBAD due to late aneurysmal degeneration of TBAD increasing morbidity and mortality at longer-term. Late surgical intervention can be prevented by early endovascular intervention when combined with optimal medical therapy. In this narrative review, we explore available literature on different endovascular therapies for TBAD in different populations of patients.

Spinal Cord Ischemia in the Setting of Acute Type B Aortic Dissection: Successful Rescue with Thoracic Endovascular Aortic Repair

We report 2 cases of successful thoracic endovascular aortic repair (TEVAR) for acute type B aortic dissection (ABAD) complicated with spinal cord ischemia (SCI). Case 1. A 70-year-old gentleman found with an uncomplicated ABAD with false lumen occluded, developed SCI shortly after admission during the initial medical management. Cerebrospinal fluid drainage (CSFD) was initiated followed by emergent TEVAR. SCI improved, and the patient was discharged. Case 2. A 52-year-old gentleman developed uncomplicated ABAD with patent false lumen. 5 hours after admission, he developed SCI during the initial medical management. Emergent TEVAR was performed followed by CSFD, and the SCI improved before discharge. These cases prompted us to address prompt TEVAR for primary entry closure and true lumen dilatation with postoperative hypertensive management to relieve the dynamic obstruction of the segmental arteries responsible for the compromised spinal cord circulation in complicated ABAD.

Differences in the clinical presentation, management, and in-hospital outcomes of acute aortic dissection in patients with and without end-stage renal disease

Background

Few studies have evaluated the clinical presentation, management, and outcomes of patients with end-stage renal disease (ESRD) presenting with acute aortic dissection (AAD) in real-world clinical practice. Thus, this study investigated the clinical characteristics, management, and outcomes of AAD patients with ESRD.

Methods

A total of 217 patients were included. We evaluated the differences in the clinical features, management, and in-hospital outcomes of patients with and without a history of ESRD presenting with AAD.

Results

A history of ESRD was present in 71 of 217 patients. Patients with ESRD had atypical clinical manifestations (p < 0.001) and were more likely to be managed medically compared with patients without ESRD (p = 0.002). Hypertension and type B aortic dissection were significantly more common among patients with ESRD. Moreover, patients with ESRD had lower leucocyte and platelet counts than patients without ESRD in laboratory findings (p < 0.001). However, hospitalization days and in-hospital mortality were similar between the two groups (p > 0.05). Multivariate analysis identified Type A aortic dissection as an independent predictor of in-hospital mortality among patients without ESRD (OR, 13.68; 95% CI, 1.92 to 98.90; P = 0.006).

Conclusions

This study highlights differences in the clinical characteristics, management, and outcomes of AAD patients with ESRD. These patients usually have atypical symptoms and more comorbid conditions and are managed more conservatively. However, these patients have no in-hospital survival disadvantage over those without ESRD. Further studies are needed to better understand and optimize care for patients with ESRD presenting with AAD.

Self-Nanoemulsifying Drug Delivery System Loaded with Psiadia punctulata Major Metabolites for Hypertensive Emergencies: Effect on Hemodynamics and Cardiac Conductance

Vasodilators are an important class of antihypertensive agents. However, they have limited clinical use due to the reflex tachycardia associated with their use which masks most of its antihypertensive effect and raises cardiac risk. Chemical investigation of Psiadia punctulata afforded five major methoxylated flavonoids (1–5) three of which (1, 4, and 5) showed vasodilator activity. Linoleic acid-based self-nanoemulsifying drug delivery system (SNEDDS) was utilized to develop intravenous (IV) formulations that contain compounds 1, 4, or 5. The antihypertensive effect of the prepared SNEDDS formulations, loaded with each of the vasodilator compounds, was tested in the angiotensin-induced rat model of hypertension. Rats were subjected to real-time recording of blood hemodynamics and surface Electrocardiogram (ECG) while the pharmaceutical formulations were individually slowly injected in cumulative doses. Among the tested formulations, only that contains umuhengerin (1) and 5,3′-dihydroxy-6,7,4′,5′-tetramethoxyflavone (5) showed potent antihypertensive effects. Low IV doses, from the prepared SNEDDS, containing either compound 1 or 5 showed a marked reduction in the elevated systolic blood pressure by 10 mmHg at 12 μg/kg and by more than 20 mmHg at 36 μg/kg. The developed SNEDDS formulation containing either compound 1 or 5 significantly reduced the elevated diastolic, pulse pressure, dicrotic notch pressure, and the systolic–dicrotic notch pressure difference. Moreover, both formulations decreased the ejection duration and increased the non-ejection duration while they did not affect the time to peak. Both formulations did not affect the AV conduction as appear from the lack of effect on p duration and PR intervals. Similarly, they did not affect the ventricular repolarization as no effect on QTc or JT interval. Both formulations decreased the R wave amplitude but increased the T wave amplitude. In conclusion, the careful selection of linoleic acid for the development of SNEDDS formulation rescues the vasodilating effect of P. punctulata compounds from being masked by the reflex tachycardia that is commonly associated with the decrease in peripheral resistance by most vasodilators. The prepared SNEDDS formulation could be suggested as an effective medication in the treatment of hypertensive emergencies, after clinical evaluation.

Outcomes and risk management in type B aortic dissection patients with acute kidney injury: a concise review

Purpose

Type B aortic dissection is a rare but life-threatening disease. Thoracic endovascular aortic repair (TEVAR) was widely used for Type B aortic dissection patients in the last decade due to the lower mortality and morbidity compared with open chest surgical repair (OCSR). AKI in type B aortic dissection is a well-recognized complication and indicates poor short-term and long-term outcome. The objective of this concise review was to identify the risk factors and the impact of AKI on type B aortic dissection patients.

Methods and results

A literature search was performed using PubMed, Embase, MEDLINE, and Cochrane Library with the search terms ‘type B aortic dissection’ and ‘acute kidney injury’ (AKI), and all English-language literatures published in print or available online from inception through August 2020 were thoroughly reviewed. Studies that reported relative AKI risks and outcomes in type B aortic dissection patient were included. Major mechanisms of AKI in type B aortic dissection included renal hypoperfusion, inflammation response, and the use of contrast medium. Type B aortic dissection patients with AKI significantly had increased hospital stay duration, need of renal replacement therapy, and 30-d and 1-year mortality.

Conclusions

AKI in type B aortic dissection is a well-recognized complication and associated with poor short-term and long-term outcome. Early identification of high-risk patients, early diagnosis of AKI, stabilization of the hemodynamic parameters, avoidance of nephrotoxic drugs, and optimization of the use of contrast agents are the major strategies for the reduction of AKI in type B aortic dissection patients.

Covered or Not, Here I Come: Stanford Type B Aortic Dissection Repair With a Covered and Uncovered Stent Hybrid Technique

The complications resulting from aortic dissections are often devastating. Historically, when a Stanford B aortic dissection extended into the visceral abdominal aorta, only surgical management was considered to limit visceral organ malperfusion. Complications of surgical management for Stanford B aortic dissections are as high as 50%. The inherently high complication and mortality rate for any acute aortic dissection, in addition to the complication rates resulting from surgical management, have demonstrated poor outcomes. This is especially true when aortic dissections involve the visceral segment, where thoracic endovascular aortic repair (TEVAR) becomes limited or contraindicated. In the last two decades, various approaches for TEVAR have improved in both endograft design and interventional technique. The current literature demonstrates improved outcomes for patients that receive TEVAR for Stanford B aortic dissections, including those that involve the visceral segment. Despite favorable prognostic advancement in TEVAR, the proven management complexity of Stanford B aortic dissections continue to reflect the pitfalls of the endovascular devices that are currently available. We describe a covered and uncovered stent hybrid technique in patients with complicated Stanford B aortic dissections involving the visceral segment, considering these deficiencies. Hundred percent technical success was demonstrated in the short and mid-term surveillance periods.

Management of acute pulmonary embolism after acute aortic dissection surgery

Acute aortic dissection (AAD) continues to be associated with high mortality and morbidity. Pulmonary embolism is also a life-threatening disease. The treatment of these life-threatening diseases remains controversial in case complications arise. Thrombolytic therapy and intensive treatment would be needed to manage these fatal diseases. A 49-year-old man with progressive back pain was admitted to our hospital. Computed tomography (CT) scan revealed type A AAD. Emergency operation for hemiarch replacement was performed. Two weeks postoperatively, the patient’s oxygenation worsened and his d-dimer levels elevated. CT scan revealed a massive thrombus in the bilateral pulmonary arteries. Intensive anticoagulation therapy was started immediately. On postoperative day 27, the patient was weaned from mechanical ventilation, but the false lumen with thrombus was recanalized again. The patient was discharged on postoperative day 75 without resulting in major complications for aortic dissection. The diagnosis of pulmonary embolism concomitant with AAD is difficult. The treatment of pulmonary embolism after AAD is controversial. Our strategy seems to be suitable for acute pulmonary embolism that occurs during the treatment of AAD.

˂Learning objective: The diagnosis of pulmonary embolism concomitant with acute aortic dissection (AAD) is difficult. The treatment of pulmonary embolism after AAD is controversial. Investigating factor XIII levels might help in the early detection of pulmonary embolism.>

Paraplegia Following Type B Acute Aortic Dissection Can Spare the Spinal Cord

Ischemic lumbosacral plexopathy secondary to an acute aortic dissection is a rare condition that is usually unilateral and frequently accompanied by a simultaneous spinal cord infarction. The functional prognosis relies on the severity of the nervous system involvement being usually worse when the spinal cord is involved. We present a case of a 46-year-old man who suffered an acute type B aortic dissection presenting as acute paraplegia due to bilateral ischemic lumbosacral plexopathy treated with thoracic endovascular aortic repair. An up-to-date review of the literature on ischemic lumbosacral plexus injury is provided.

Case report: left monoplegia in acute type B aortic dissection

Acute type B aortic dissection (ATBAD) with malperfusion is a devastating complication. Especially, the spinal cord ischemia with ATBAD is very rare (3% of total malperfusion cases). Despite the possibility of various arterial involvement in ATBAD, cases of monoplegia due to spinal cord ischemia are extremely rare. Furthermore effective treatments for malperfusion induced spinal cord ischemia have not been established yet. We presented a case of a 62-year-old man with a sudden onset of chest pain and numbness and weakness of the left lower extremity. Follow up CT demonstrated ATBAD starting from below the left subclavian artery to the level of iliac bifurcation without distal reentry, involving malperfusion of the left renal, left intercostal and left lumbar arterial branches. Deciding on endovascular fenestration approach under considering his condition and comorbidity, the right common femoral artery was catheterized and a 5Fr sheath catheter was positioned into the true lumen (Cook Medical, IN, USA). After confirming the catheter was within the compressed true lumen, then aortic fenestration ballooning was performed to enlarge a tearing site by using 12-mm and 20-mm diameter balloons (Boston Scientific, Natick, Mass). The final angiography was demonstrated increased flow in the true lumen of descending aorta with good patency of the left renal artery where no flow had been observed. And enhanced CT confirmed the recovery of flow to the left intercostal and left lumbar branches. Finally the patient achieved the complete recovery of sensory and motor function of his left leg (His preoperative motor grade was 5/0). On postoperative day 3, he walked using a q-cane and now is being followed up on an outpatient basis without no complications. So, we would like to introduce this rare care of left lower monoplegia with ATBAD and suggest endovascular fenestration can be an effective treatment option to treat spinal cord ischemia in ATBAD.

A Case Report of Thoracic Endovascular Aneurysm Repair under Local Anesthesia with Resolution of Acute Onset Lower Extremity Paraplegia from an Acute Complicated Type B Aortic Dissection

Spinal cord ischemia (SCI) is a rare presenting symptom of acute complicated type B aortic dissection, occurring in approximately 3% of patients . We present a case report of a patient with this presentation who had observed resolution of his paraplegia symptoms immediately after placement of a thoracic stent graft under local anesthesia. The temporal association between true lumen flow restoration and paraplegia resolution intraoperatively is a novel finding. We feel that this case report may provide support for recognized cord perfusion theory , as well as contribute to the understanding of the time frame associated with SCI and reversibility of paraplegia.

Clinical benefits of fast-track rehabilitation program for patients with uncomplicated type B acute aortic dissection

OBJECTIVES

Uncomplicated type B acute aortic dissection (UTBAAD) has traditionally been treated medically. Although patients are treated based on the rehabilitation program established by the Japanese Circulation Society, we sometimes encounter patients with complications related to the long duration of bed rest. We performed novel fast-track rehabilitation for UTBAAD, which consisted of short-duration bed rest and the early initiation of walking under secure blood pressure control.

METHODS AND RESULTS

From April 2009 to February 2017, there were 73 consecutive cases of UTBAAD. Conventional medical treatment was administered to 39 patients (group G) during the early period. From August 2013, 34 patients (group F) received our 'fast-track' rehabilitation program, which consisted of the following: oral intake and assuming a sitting position from day 1 after the onset, standing by the bed from day 2, walking in their room from day 4, and discharge from day 16 if all goes smoothly. Group F had a significantly earlier initiation of standing and walking, first defecation, and weaning from oxygen and intravenous antihypertensive agents than group G. The pneumonia complication rate was significantly lower in group F than in group G. The hospitalization duration was markedly shorter and the in-hospital expense lower in group F than in group G. There were no significant differences in the rate of late adverse aortic events within 12 months after onset.

CONCLUSIONS

Our fast-track rehabilitation program for patients with UTBAAD resulted in a better in-hospital clinical course and lower expense than conventional medical treatment without any adverse aortic events.

Thoracic endovascular aneurysm repair to treat recurrent lower limb ischemia secondary to occlusion of axillofemoral bypass

•

One of the complications of type B aortic dissection is organ ischemia.

•

TEVAR was performed for entry closure.

•

TEVAR improved malperfusion.

Introduction

A case of malperfusion in which the patient presented with aortic dissection is presented.

Presentation of case

A 69-year-old man with an acute aortic dissection (Stanford type B) had lower limb ischemia. Axillary-femoral bypass was performed, and his lower limb ischemia improved. Eight months after the onset of acute aortic dissection, he again had lower limb ischemia. Contrast-enhanced computed tomography showed axillary-femoral bypass occlusion and true lumen collapse, compressed by the increased false lumen pressure in the aorta. Thoracic endovascular aortic repair (TEVAR) was performed for entry closure. His lower limb ischemia was improved by TEVAR.

Discussion

One of the complications of type B aortic dissection is malperfusion. Endovascular therapy is a first step in treating the malperfusion of type B aortic dissection. It is important to seal the entry for the treatment of malperfusion.

Conclusion

If there is an entry, it is important to seal it for the treatment of malperfusion.

Computed tomography findings and in-hospital mortality in patients with rupture of type B aortic dissection

Background

The relationships between the computed tomography (CT) findings and outcomes of patients with ruptured type B aortic dissection have not been clarified.

Purpose

To evaluate the initial CT findings of patients with ruptured type B aortic dissection and investigate the relationships between the initial CT findings and in-hospital mortality.

Material and Methods

This study was approved by the institutional review board. Thirty-three patients were diagnosed with ruptured Stanford type B aortic dissection at our hospital between 2007 and 2016 (21 men, 12 women; mean age = 76.1±10.7 years). We retrospectively evaluated the initial CT findings of ruptured type B aortic dissection and the relationships between clinical factors and in-hospital mortality using logistic regression analysis.

Results

Type B aortic dissections ruptured in the acute and chronic phases in 23 and 10 patients, respectively. The initial CT images showed various findings, including an open false lumen (58%), arch involvement (88%), hematomas in the pleural space (55%), hematomas in the pericardial space (18%), and the extravasation of vascular contrast material (12%). The mean maximum diameter of the affected aorta was 49.5 ± 16.1 mm. Among the 33 patients, 14 died at hospital. Female gender (hazard ratio = 10.284; 95% confidence interval [CI] = 1.61–65.54; P = 0.0136) and the presence of a hematoma in the pleural space (hazard ratio = 6.803; 95% CI = 1.07–43.24; P = 0.0421) were found to be predictors of in-hospital mortality.

Conclusion

Female gender and the presence of a hematoma in the pleural space are significant predictors of in-hospital mortality in patients with ruptured type B aortic dissection.

Thoracic endovascular aortic repair versus open chest surgical repair for patients with type B aortic dissection: a systematic review and meta-analysis

Aim: This meta-analysis study aimed to compare the efficacy and safety of TEVAR versus OCSR for TBAD patients.Methods: We systematically searched PubMed, EmBase, and the Cochrane library to identify studies compared the effectiveness of TEVAR and OCSR in TBAD patients from the inception up to July 2019. The summary results were calculated using a random-effects model.Results: The electronic search identified 1,894 studies, and 18 studies with 9,664 TBAD patients were included. We noted patients received TEVAR were associated with a reduced risk of in-hospital mortality, acute renal failure, respiratory failure, and bleeding as compared with OCSR, whereas no significant differences between groups for the risk of stroke, myocardial infarction, paraplegia, mesenteric ischaemia/infarction, reinterventions, sepsis, and spinal cord ischaemia.Conclusions: The findings of this meta-analysis study suggested that TEVAR resulted in more short-term survival benefits. Moreover, the reduced risk of acute renal failure, respiratory failure and bleeding was detected in TEVAR group. The treatment effects of TEVAR versus OCSR on specific complications should be further verified by a study with high-level of evidence.Key messageComprehensive collected studies investigated the treatment effectiveness between TEVAR and OCSR for TBAD patientsTEVAR resulted in more survival benefits, in addition to lower risk of acute renal failure, respiratory failure and bleedingThe results of stratified analyses according to patients' characteristics were conducted.

Acute Type B Dissection

Aortic dissections are catastrophic vascular emergencies, and early recognition and appropriate interventions can be crucial to survival. Research has changed the way aortic dissections are managed over the past two decades and will continue to contribute to the evolution of treatment modalities. Early treatment for uncomplicated type B dissections still remains controversial but certain characteristics may benefit from early intervention.

Left ventricular hypertrophy is a possible biomarker for early mortality after type B aortic dissection

OBJECTIVE

Data regarding the cardiac abnormalities associated with Stanford type B aortic dissection (TBAD) and whether these abnormalities are related to outcomes are limited. We describe the prevalence of cardiac abnormalities in patients with TBAD as detected by echocardiography.

METHODS

This retrospective review included patients with TBAD presenting between 1990 and 2016. Echocardiograms performed within 6 weeks of acute TBAD were reviewed. Cardiac function, valve abnormalities, and stigmata of hypertensive heart disease including left ventricular hypertrophy (LVH) were ascertained. Characteristics of patients who did and did not receive echocardiograms were compared. Outcomes of patients with and without evidence of LVH on echocardiography were also compared.

RESULTS

Of 239 patients with TBAD, 90 had echocardiograms performed within 6 weeks of acute TBAD (74% male; mean age, 57.8 ± 13.2 years). Echocardiograms were obtained at a median of 2 days (range, 0-41 days) from acute TBAD. Patients who had echocardiograms were more likely to present with malperfusion (28% vs 14%; P < .01) and had a trend toward increased operative repair during the subacute phase (17.4% vs 9.5%; P = .07) compared with patients who did not receive an echocardiogram. A majority of patients (57%) had at least mild LVH, including 39% of patients without a prior diagnosis of hypertension. Fibrocalcific changes associated with hypertension, including aortic sclerosis and mitral annular calcification, were noted in 40% and 11% of the patients, respectively. Among patients with LVH, there was a trend toward higher all-cause mortality (35% vs 23%; P = .21) and a younger age at death (58 ± 14 years vs 66 ± 13 years; P = .19) despite a similar age at TBAD onset. In a multivariable analysis controlling for age, sex, and admission estimated glomerular filtration rate, LVH independently predicted all-cause mortality (hazard ratio, 2.38; 95% confidence interval, 1.02-5.56; P = .04).

CONCLUSIONS

LVH and other findings of hypertensive heart disease are common in patients with TBAD. LVH predicted all-cause mortality after TBAD in this small group of patients. Further exploration of the relationship between the chronic effects of hypertension and using LVH as an objective biomarker to risk stratify patients with TBAD and long-term outcomes after TBAD is warranted.

Cerebrovascular injuries found in acute type B aortic dissections are associated with blood pressure derangements and poor outcome

OBJECTIVE

Cerebrovascular injury (CVI) is a recognized but underappreciated complication of acute type B aortic dissection (ATBAD). This study was performed to determine risk factors for CVI associated with ATBAD and, in particular, the possible contributory role of aggressive anti-impulse therapy.

METHODS

A retrospective review of all patients presenting to a tertiary medical center with an ATBAD between January 2003 and October 2012 was conducted. All CVIs were adjudicated by a vascular neurologist and assigned a probable cause. The initial intensity of anti-impulse therapy was defined as the difference in mean arterial pressure (ΔMAP) from presentation to subsequent admission to the intensive care unit.

RESULTS

A total of 112 patients were identified. The average age was 61 years; 64% were male, and 59% were African American. Twenty patients required operative intervention (14 thoracic endovascular aortic repairs and 6 open). CVI occurred in 13 patients (11.6%): 9 were hypoperfusion related (6 diffuse hypoxic brain injuries and 3 watershed infarcts), 2 were procedure related (both thoracic endovascular aortic repairs), 1 was an intracranial hemorrhage on presentation, and 1 was a probable embolic stroke on presentation. CVI patients had demographics and comorbidities comparable to those of the non-CVI patients. CVI was associated with operative intervention (54% vs 13%; P = .002). Thirty-day mortality was significantly higher in CVI patients (54% vs 6%; P < .001). Patients who suffered a hypoperfusion brain injury had a higher MAP on presentation to the emergency department (142 mm Hg vs 120 mm Hg; P = .034) and a significantly greater reduction in MAP (ΔMAP 49 mm Hg vs 15 mm Hg; P < .001) by the time they reached the intensive care unit compared with the non-CVI patients.

CONCLUSIONS

In our series, CVI in ATBAD is more frequent than previously reported and is associated with increased mortality. The most common causes are related to cerebral hypoperfusion. Higher MAP on presentation and greater decline in MAP are associated risk factors for hypoperfusion-related CVI. A less aggressive approach to lowering MAP in ATBAD warrants further study in an attempt to reduce CVI in ATBAD.

Quantitative Study of Abdominal Blood Flow Patterns in Patients with Aortic Dissection by 4-Dimensional Flow MRI

The purpose of this study is to evaluate the hemodynamic characteristics of the true lumen (TL) and the false lumen (FL) in 16 patients with aortic dissection (AD) using 4D flow magnetic resonance imaging (MRI) and thoracic and abdominal computed tomography (CT) angiography. The quantitative parameters that were measured in the TL and FL included velocity and flow. The mean area and regurgitant fraction of the TL were significantly lesser at all four levels (p < 0.05); the average through-plane velocity, peak velocity magnitude, average net flow, peak flow, and net forward volume in the TL were considerably higher (p < 0.05). The intimal entry's size was negatively correlated with the blood flow velocity and flow rate in the TL (p < 0.05) and positively correlated with the average through-plane velocity, average net flow, and peak flow in the FL (p < 0.05); the blood flow indices in the TL were enhanced with an increase in the intimal entry numbers (p < 0.05) and the peak flow in the FL was lowered (p = 0.025); if FL thrombosis existed, the average through-plane velocity and peak velocity magnitude in the TL were substantially higher (p < 0.05). 4D flow MRI facilitates qualitative and quantitative analysis of the alterations in the abdominal aortic blood flow patterns.

Conservative management versus endovascular or open surgery in the spectrum of type B aortic dissection

Background

Type B aortic dissection is a life-threatening acute aortic condition often with acute ischemic signs or symptoms. With initial management focusing on alleviating malperfusion and pain, and avoiding propagation of dissection or rupture both systolic blood and pulse pressure should be reduced initially by an aggressive medical approach. In the setting of persistent signs of complications endovascular strategies have replaced open surgery and led to a fourfold increase in early survival and better long-term outcomes.

Methods

An electronic health database search was performed on articles published between January 2006 and July 2017. Publications were included in this review if (I) the index aortic pathology was type B aortic (distal) dissection; (II) when medical management, open surgical replacement or thoracic endovascular aortic repair were among those options; (III) when at least one of all basic outcome criteria such as survival, spinal cord ischemia and cerebrovascular accident was reported; (IV) when ≥15 serial patients were included. A total of 62 studies were eligible and analysed.

Results

Our manuscript has summarized data collected over 12 years on management specific outcomes in the setting of distal aortic dissection and provides an up-to-date interpretation of the published evidence. For complicated cases, treated acutely, the 30-day or in-hospital mortality was 7.3% when managed by endovascular means, whereas the pooled rate for 30-day or in-hospital mortality was 19.0% when subjected to open repair. For acute uncomplicated type B dissection usually treated with blood pressure lowering medications, the pooled 30-day or in-hospital mortality rate was 2.4%. Survival rates at 5 years averaged at 60% (40% mortality). Freedom from any aortic event ranged from 34.0% to 83.9%, underlining an inherent risk of progression and late complications. For chronic complicated type B dissection, the rates of stroke, paraplegia and operative mortality following endovascular repair ranged from 5% to 13%, 2% to 13% and 2 to 13%, respectively, while 5-year survival rates after open repair ranged from 60% to 90%. In chronic uncomplicated type B dissection almost 90% of patients survive initial hospitalization and were subjected to medical management with a 5-year survival of 50-80%. However, up to 20-55% of medically treated patients develop aneurysmal degeneration after 5 years with an unknown risk of rupture.

Conclusions

Currently, the less invasive strategy of endovascular repair (as compared to open surgery) provides improved 30-day or in-hospital survival in the setting of complicated acute type B aortic dissection and may seek broad application. Open surgical aortic reconstruction should be left to experienced aortic centres if endovascular management is not an option.

New type A dissection after acute type B aortic dissection

OBJECTIVE

Aortic dissection is a dynamic process that can progress both proximal and distal to the initial entry tear. We sought to determine associations for development of proximal progression or new type A aortic dissection (NTAD) after acute type B dissection (ATBD) and its effect on survival of the patient.

METHODS

We reviewed all cases of acute aortic dissection that we managed from 1999 to 2014. Univariate and bivariate analyses were performed to identify correlates of NTAD. Multivariable regression and proportional hazards regression analysis was done to determine the effect of dissection progression on long-term survival.

RESULTS

Among 477 cases of ATBD managed, 19 (4.0%) patients developed NTAD during a median follow-up of 4.1 (interquartile range, 1.4-7.7) years. Median time from diagnosis of ATBD to NTAD was 124 (interquartile range, 23-1201) days. Baseline predictors for development of NTAD at initial ATBD admission included bicuspid aortic valve (P = .006) and age <60 years (P = .012). Although not statistically significant, point estimates indicate that thoracic endovascular aortic repair was twice as frequent in NTAD cases as in non-NTAD cases. Overall 5-year survival was 70.2%. Patients who had repair of NTAD appear to have longer survival, although this effect is on the margin of statistical significance (P = .051). After risk factor and correlates of NTAD adjustment, this effect was no longer apparent (P = .089).

CONCLUSIONS

The natural history of ATBD is such that there is a persistent risk of NTAD, with the highest risk in the first 6 months. Factors associated with NTAD include bicuspid aortic valve and young age. Thoracic endovascular aortic repair did not have a large effect on risk. Timely diagnosis and repair of NTAD are associated with good survival rates. Lifelong surveillance is warranted in all cases of descending thoracic aortic dissection regardless of initial treatment modality.

Total Endovascular Treatment of Acute Non-A-non-B Dissection Complicated by Visceral Malperfusion without Primary Entry Tear Coverage

Management of visceral ischemia due to non-A, non-B dissection is extremely challenging due to the position of the primary entry tear at the level of the brachiocephalic vessels. We report on a patient who was admitted for a complicated non-A, non-B-type dissection with visceral and leg ischemia. A covered stent graft was implanted below the primary entry tear to redirect the flow in the true lumen, associated with stents implantation in the visceral arteries, to treat the dissection's static component. The patient did well, without need for bowel resection visceral or late stent restenosis. Stent-graft implantation below the primary entry tear in cases of visceral ischemia due to non-A, non-B dissection seems feasible.

Aortic Elongation and Stanford B Dissection: The Tübingen Aortic Pathoanatomy (TAIPAN) Project

OBJECTIVE/BACKGROUND

Aortic elongation has not yet been considered as a potential risk factor for Stanford type B dissection (TBD). The role of both aortic elongation and dilatation in patients with TBD was evaluated.

METHODS

The aortic morphology of a healthy control group (n = 236) and patients with TBD (n = 96) was retrospectively examined using three dimensional computed tomography imaging. Curved multiplanar reformats were used to examine aortic diameters at defined landmarks and aortic segment lengths.

RESULTS

Diameters at all landmarks were significantly larger in the TBD group. The greatest diameter difference (56%) was measured in dissected descending aortas (p < .001). The segment with the most considerable difference between the study groups with regard to elongation was the non-dissected aortic arch of patients with TBD (36%; p < .001). Elongation in the aortic arch was accompanied by a diameter increase of 21% (p < .001). In receiver-operating curve analysis, the area under the curve was .85 for the diameter and .86 for the length of the aortic arch.

CONCLUSIONS

In addition to dilatation, aortic arch elongation is associated with the development of TBD. The diameter and length of the non-dissected aortic arch may be predictive for TBD and may possibly be used for risk assessment in the future. This study provides the basis for further prospective evaluation of these parameters.

Prognostic significance of early aortic remodeling in acute uncomplicated type B aortic dissection and intramural hematoma

BACKGROUND

Patients with Stanford type B aortic dissections (ADs) are at risk of long-term disease progression and late complications. The aim of this study was to evaluate the natural course and evolution of acute type B AD and intramural hematomas (IMHs) in patients who presented without complications during their initial hospital admission and who were treated with optimal medical management (MM).

METHODS

Databases from 2 aortic centers in Europe and the United States were used to identify 136 patients with acute type B AD (n = 92) and acute type B IMH (n = 44) who presented without complications during their index admission and were treated with MM. Computed tomography angiography scans were available at onset (≤14 days) and during follow-up for those patients. Relevant data, including evidence of adverse events during follow-up (AE; defined according to current guidelines), were retrieved from medical records and by reviewing computed tomography scan images. Aortic diameters were measured with dedicated 3-dimensional software.

RESULTS

The 1-, 2-, and 5-year event-free survival rates of patients with type B AD were 84.3% (95% confidence interval [CI], 74.4-90.6), 75.4% (95% CI, 64.0-83.7), and 62.6% (95% CI, 68.9-73.6), respectively. Corresponding estimates for IMH were 76.5% (95% CI, 57.8-87.8), 76.5% (95% CI, 57.8-87.8), and 68.9% (95% CI, 45.2-83.9), respectively. In patients with type B AD, risk of an AE increased with aortic growth within the first 6 months after onset. A diameter increase of 5 mm in the first half year was associated with a relative risk for AE of 2.29 (95% CI, 1.70-3.09) compared with the median 6 months' growth of 2.4 mm. In approximately 60% of patients with IMH, the abnormality resolved within 12 months and in the patients with nonresolving IMH, risk of an adverse event was greatest in the first year after onset and remained stable thereafter.

CONCLUSIONS

More than one third of patients with initially uncomplicated type B AD suffer an AE under MM within 5 years of initial diagnosis. In patients with nonresolving IMH, most adverse events are observed in the first year after onset. In patients with type B AD an early aortic growth is associated with a greater risk of AE.

Computed Tomography Imaging Features in Acute Uncomplicated Stanford Type-B Aortic Dissection Predict Late Adverse Events

BACKGROUND

Medical treatment of initially uncomplicated acute Stanford type-B aortic dissection is associated with a high rate of late adverse events. Identification of individuals who potentially benefit from preventive endografting is highly desirable.

METHODS AND RESULTS

The association of computed tomography imaging features with late adverse events was retrospectively assessed in 83 patients with acute uncomplicated Stanford type-B aortic dissection, followed over a median of 850 (interquartile range 247-1824) days. Adverse events were defined as fatal or nonfatal aortic rupture, rapid aortic growth (>10 mm/y), aneurysm formation (≥6 cm), organ or limb ischemia, or new uncontrollable hypertension or pain. Five significant predictors were identified using multivariable Cox regression analysis: connective tissue disease (hazard ratio [HR] 2.94, 95% confidence interval [CI]: 1.29-6.72; P=0.01), circumferential extent of false lumen in angular degrees (HR 1.03 per degree, 95% CI: 1.01-1.04, P=0.003), maximum aortic diameter (HR 1.10 per mm, 95% CI: 1.02-1.18, P=0.015), false lumen outflow (HR 0.999 per mL/min, 95% CI: 0.998-1.000; P=0.055), and number of intercostal arteries (HR 0.89 per n, 95% CI: 0.80-0.98; P=0.024). A prediction model was constructed to calculate patient specific risk at 1, 2, and 5 years and to stratify patients into high-, intermediate-, and low-risk groups. The model was internally validated by bootstrapping and showed good discriminatory ability with an optimism-corrected C statistic of 70.1%.

CONCLUSIONS

Computed tomography imaging-based morphological features combined into a prediction model may be able to identify patients at high risk for late adverse events after an initially uncomplicated type-B aortic dissection.

Technical Aspects of Open Repair for Degenerative Aneurysmal Evolution Despite Early Thoracic Endovascular Repair of Type B Aortic Dissection

BACKGROUND

Closure of the proximal tear by thoracic endovascular aortic repair (TEVAR) at the acute phase appears to be a safe effective treatment to prevent aneurysmal degeneration type B dissection. However, it appears to be inefficient in up to a third of the patient. We report the technical aspects of our experience with patients undergoing secondary open repair after TEVAR for dissecting thoracoabdominal aneurysm despite early closure proximal tear by TEVAR.

METHODS

During a period of 5 years, 96 patients presenting acute type B aortic dissections were treated by TEVAR and followed-up in our institution. Among them, 5 patients experienced an evolution to a dissecting thoracoabdominal aortic aneurysm. Their demographic data and initial medical conditions, delay to reintervention, operative technical details, perioperative and mid-term outcomes were collected and analyzed.

RESULTS

All 5 patients (4 male, mean age 58 ± 9) were operated under peripheral normothermic bypass without deep circulatory arrest using the thoracic stent graft as an elephant trunk for completion of the proximal anastomosis. In cases of patency, the false lumen was reapproximated in the anastomosis, 6 visceral arteries were revascularized selectively. One patient died at day 1 of perioperative ventricular fibrillation due to an acute myocardial infarction. The 4 others are alive without complication after a median of 30 months, range (13-22).

CONCLUSIONS

In our experience, TEVAR was not only efficient at the acute phase to deal with complications, but in cases of subsequent aneurysmal evolution, it made open repair even easier by avoiding very proximal cross-clamping/anastomosis and circulatory arrest.