Endovascular Repair of Penetrating Thoracic Aortic Ulcers Using Tubular Stent Grafts Versus Stent Grafts With a Proximal Scallop.

PURPOSE: In penetrating aortic ulcers (PAUs), limited data support tubular thoracic endovascular aortic repair (TEVAR) as a viable treatment option. For treatment of more proximal PAUs, hybrid approaches and-more recently-scalloped TEVAR (scTEVAR) have been advocated. Outcomes of scTEVAR specifically for PAUs have not yet been reported. This study reports long-term outcomes for tubular and scTEVAR in PAUs and compares the safety profile in both cohorts regarding the significantly more proximal landing zone (LZ) for scTEVAR. MATERIALS AND METHODS: This single-center retrospective cohort study includes all nonacute patients treated for complicated PAU with scTEVAR and tubular TEVAR. Patient and PAU characteristics as well as procedural success, complication and reintervention rates, and all-cause and aortic mortality were analyzed. RESULTS: Of 212 TEVAR procedures reviewed, 21 patients with tubular TEVAR and 19 patients with scTEVAR were included. Patient and PAU characteristics were similar, and LZ was significantly more proximal in the scTEVAR cohort (p=0.0001), with similar number and types of supra-aortic revascularization procedures. Clinical success was reached in all 40 patients (100%), and reintervention rate was 2/21 (9.5%) and 1/19 (5.3%), respectively. Over the mean follow-up of 63 (TEVAR) and 53 (scTEVAR) months, clinical success was stable in all patients with one (abdominal) aortic-related mortality in the scTEVAR cohort. CONCLUSION: Treatment of complicated PAUs with TEVAR as well as scTEVAR provides excellent and similar clinical success, stability of clinical success, and aortic survival with acceptable complication and reintervention rates. Scalloped TEVAR safely lengthens the proximal sealing zone to address more proximal pathologies. CLINICAL IMPACT: Treatment of asymptomatic complicated penetrating aortic ulcers (PAUs) with thoracic endovascular aortic repair (TEVAR) provides excellent clinical success and acceptable complication and reintervention rates. More patients become amenable to endovascular treatment by including scalloped TEVAR (scTEVAR) as a means to safely lengthen the proximal sealing zone to address more proximal pathologies.

Applicability of endovascular branched and fenestrated aortic arch repair devices to treat residual type A dissection after ascending replacement.

OBJECTIVE: Endovascular repair of post-type A aortic dissection (PTAD) after open ascending replacement has recently been shown as safe and feasible, but with limited anatomic applicability because only one stent graft was evaluated. We assessed anatomic and clinical applicability of six commercially available branched/fenestrated stent grafts for endovascular repair of PTAD. METHODS: On postoperative CT scans of 101 patients, we measured the aortic diameter at the sinutubular junction, supra-aortic vessels, and descending aorta, as well as the distances between these landmarks along the outer curvature of the arch and the diameters of the supra-aortic vessel. Anatomic applicability was evaluated according to the instructions for use, clinical applicability with regard to supra-aortic and iliac arteries. Assessed devices were the Cook aortic double branch, Terumo double branch, Najuta fenestrated, Endospan Nexus, Medtronic Mona LSA, and Gore TAG thoracic branch. RESULTS: Single devices were anatomically and clinically applicable between 19 of 101 (Mona LSA) and 83 of 101 (Najuta) cases. Reasons for rejection varied considerably across devices. With all devices available, anatomic applicability was 97 of 101 and clinical applicability 95 of 101. Combinations of a fenestrated and a branched device showed the most favorable clinical applicability for a pair of two devices, ranging from 86 of 101 to 94 of 101. CONCLUSIONS: Anatomic and clinical applicability of endovascular devices for the repair of PTAD is high for fenestrated and branched devices, and very high for the combination of fenestrated and branched devices. Manufacturers should amend specific device requirements for PTAD. Surgeons should emphasize the need for a sufficiently long and straight graft as a potential landing zone.

The Role of Telocytes and Telocyte-Derived Exosomes in the Development of Thoracic Aortic Aneurysm.

A hallmark of thoracic aortic aneurysms (TAA) is the degenerative remodeling of aortic wall, which leads to progressive aortic dilatation and resulting in an increased risk for aortic dissection or rupture. Telocytes (TCs), a distinct type of interstitial cells described in many tissues and organs, were recently observed in the aortic wall, and studies showed the potential regulation of smooth muscle cell (SMC) homeostasis by TC-released shed vesicles. The purpose of the present work was to study the functions of TCs in medial degeneration of TAA. During aneurysmal formation an increase of aortic TCs was identified in human surgical specimens of TAA-patients, compared to healthy thoracic aortic (HTA)-tissue. We found the presence of epithelial progenitor cells in the adventitial layer, which showed increased infiltration in TAA samples. For functional analysis, HTA- and TAA-telocytes were isolated, characterized, and compared by their protein levels, mRNA- and miRNA-expression profiles. We detected TC and TC-released exosomes near SMCs. TAA-TC-exosomes showed a significant increase of the SMC-related dedifferentiation markers KLF-4-, VEGF-A-, and PDGF-A-protein levels, as well as miRNA-expression levels of miR-146a, miR-221 and miR-222. SMCs treated with TAA-TC-exosomes developed a dedifferentiation-phenotype. In conclusion, the study shows for the first time that TCs are involved in development of TAA and could play a crucial role in SMC phenotype switching by release of extracellular vesicles.

Impacts of Telomeric Length, Chronic Hypoxia, Senescence, and Senescence-Associated Secretory Phenotype on the Development of Thoracic Aortic Aneurysm.

Thoracic aortic aneurysm (TAA) is an age-related and life-threatening vascular disease. Telomere shortening is a predictor of age-related diseases, and its progression is associated with premature vascular disease. The aim of the present work was to investigate the impacts of chronic hypoxia and telomeric DNA damage on cellular homeostasis and vascular degeneration of TAA. We analyzed healthy and aortic aneurysm specimens (215 samples) for telomere length (TL), chronic DNA damage, and resulting changes in cellular homeostasis, focusing on senescence and apoptosis. Compared with healthy thoracic aorta (HTA), patients with tricuspid aortic valve (TAV) showed telomere shortening with increasing TAA size, in contrast to genetically predisposed bicuspid aortic valve (BAV). In addition, TL was associated with chronic hypoxia and telomeric DNA damage and with the induction of senescence-associated secretory phenotype (SASP). TAA-TAV specimens showed a significant difference in SASP-marker expression of IL-6, NF-κB, mTOR, and cell-cycle regulators (γH2AX, Rb, p53, p21), compared to HTA and TAA-BAV. Furthermore, we observed an increase in CD163+ macrophages and a correlation between hypoxic DNA damage and the number of aortic telocytes. We conclude that chronic hypoxia is associated with telomeric DNA damage and the induction of SASP in a diseased aortic wall, promising a new therapeutic target.

Telocytes in the human ascending aorta: Characterization and exosome-related KLF-4/VEGF-A expression.

Telocytes (TCs), a novel interstitial cell entity promoting tissue regeneration, have been described in various tissues. Their role in inter-cellular signalling and tissue remodelling has been reported in almost all human tissues. This study hypothesizes that TC also contributes to tissue remodelling and regeneration of the human thoracic aorta (HTA). The understanding of tissue homeostasis and regenerative potential of the HTA is of high clinical interest as it plays a crucial role in pathogenesis from aortic dilatation to lethal dissection. Therefore, we obtained twenty-five aortic specimens of heart donors during transplantation. The presence of TCs was detected in different layers of aortic tissue and characterized by immunofluorescence and transmission electron microscopy. Further, we cultivated and isolated TCs in highly differentiated form identified by positive staining for CD34 and c-kit. Aortic-derived TC was characterized by the expression of PDGFR-α, PDGFR-ß, CD29/integrin ß-1 and αSMA and the stem cell markers Nanog and KLF-4. Moreover, TC exosomes were isolated and characterized for soluble angiogenic factors by Western blot. CD34+ /c-kit+ TCs shed exosomes containing the soluble factors VEGF-A, KLF-4 and PDGF-A. In summary, TC occurs in the aortic wall. Correspondingly, exosomes, derived from aortic TCs, contain vasculogenesis-relevant proteins. Understanding the regulation of TC-mediated aortic remodelling may be a crucial step towards designing strategies to promote aortic repair and prevent adverse remodelling.

Time of day does not influence outcomes in acute type A aortic dissection: Results from the IRAD.

BACKGROUND: Type A acute aortic dissection (TAAAD) represents a surgical emergency requiring intervention regardless of time of day. Whether such a "evening effect" exists regarding outcomes for TAAAD has not been previously studied using a large registry data. METHODS: Patients with TAAAD were identified from the International Registry of Acute Aortic Dissections (1996-2019). Outcomes were compared between patients undergoing operative repair during the daytime (D), defined as 8 am-5 pm, versus the evening (N), defined as 5 pm-8 am. RESULTS: Four thousand one-hundrd and ninety-seven surgically treated patients with TAAAD were identified, with 1824 patients undergoing daytime surgery (43.5%) and 2373 patients undergoing evening surgery (56.5%). Daytime patients were more likely to have undergone prior cardiac surgery (13.2% vs. 9.5%; p < .001) and have had a prior aortic dissection (4.8% vs. 3.4%; p = .04). Evening patients were more likely to have been transferred from a referring hospital (70.8% vs. 75.0%; p = .003). Daytime patients were more likely to undergo aortic valve sparing root procedures (23.3% vs. 19.2%; p = .035); however, total arch replacement was performed with equal frequency (19.4% vs. 18.8%; p = .751). In-hospital mortality (D: 17.3% vs. N. 16.2%; p = .325) was similar between both groups. Subgroup analysis examining the effect of weekend presentation revealed no significant mortality difference. CONCLUSIONS: A majority of TAAAD patients underwent surgical repair at night. There were higher rates of postoperative tamponade in evening patients; however, mortality was similar. The expertise of cardiac-dedicated operative and critical care teams regardless of time of day as well as training paradigms may explain similar mortality outcomes in this high risk population.

Insights From the International Registry of Acute Aortic Dissection: A 20-Year Experience of Collaborative Clinical Research.

Acute aortic dissection (AAD) is a life-threatening condition associated with high morbidity and mortality rates, and it remains a challenge to diagnose and treat. The International Registry of Acute Aortic Dissection was established in 1996 with the mission to raise awareness of this condition and provide insights to guide diagnosis and treatment. Since then, >7300 cases have been included from >51 sites in 12 countries. Although presenting symptoms and physical findings have not changed significantly over this period, the use of computed tomography in the diagnosis has increased, and more patients are managed with interventional procedures: surgery in type A AAD and endovascular therapy in type B AAD; with these changes in care, there has been a significant decrease in overall in-hospital mortality in type A AAD but not in type B AAD. Herein, we summarized the key lessons learned from this international registry of patients with AAD over the past 20 years.

Thoracic endovascular repair for acute complicated type B aortic dissections.

OBJECTIVE: This study retrospectively assessed in-hospital mortality and long-term results of emergency thoracic endovascular aortic repair (TEVAR) for patients with life-threatening acute complicated type B aortic dissection (acTBD). METHODS: Between March 2001 and December 2016, there were 55 patients (40 male; median age, 52 ± 13 years) with an acTBD who were treated with TEVAR for malperfusion (58%), aortic rupture (18%), or persistent untreatable pain with true lumen reduction or rapid aortic diameter enlargement (24%) as a sign of disease progression. The patients were categorized according to clinical appearance into two groups: group A, malperfusion, pending rupture, or rupture; and group B, persistent ongoing pain, rapid enlargement of aortic diameter, or significant changes in the true to false lumen ratio. Four patients (7%) had undergone previous aortic surgery. RESULTS: Technical success (coverage of the primary intimal tear) was achieved in 50 patients (91%). The overall in-hospital mortality rate was 9% (n = 5), and there was a statistically significant difference in early mortality between group A and group B (7% vs 2%; P < .02). Causes of in-hospital death were all aorta related, including a rupture during the procedure and on the first postinterventional day in two patients and redissection (ascending aorta, n = 2; descending aorta, n = 1) with a consequent aortic rupture after TEVAR in the remaining three. Permanent neurologic dysfunction occurred in five patients (stroke, n = 2; paraplegia, n = 3). Overall, 19 patients (34%) developed early endoleaks (type IA, n = 5; type IB, n = 11; type II, n = 2; type IB plus type II, n = 1). Therefore, 5 patients needed early (within 30 days) endovascular intervention because of a type IA (n = 2), type IB (n = 3), or type II endoleak (n = 1) and the rapid progression of aortic diameter, persistent signs of ischemia (n = 2), or rupture (n = 1), whereas the remaining 14 patients were treated conservatively and followed up by computed tomography angiography. Seven patients with early endoleaks needed an endovascular intervention (n = 3) or conventional surgery (n = 4) because of aortic progression in the follow-up period (mean interval after procedure, 92 ± 56 months). The actual survival rates were 87%, 85%, and 75% at 1 year, 2 years, and 5 years, respectively, and freedom from aorta-related death was 87%, 87%, and 77% at 1 year, 2 years, and 5 years, respectively. Freedom from reintervention for any cause using a Kaplan-Meier analysis was 70%, 68%, 68%, and 63% at 6 months, 1 year, 2 years, and 5 years, respectively. CONCLUSIONS: TEVAR of acTBD has been proven to be an excellent treatment modality in this cohort of high-risk patients, with promising midterm and long-term results.

Strong Signs for a Weak Wall in Tricuspid Aortic Valve Associated Aneurysms and a Role for Osteopontin in Bicuspid Aortic Valve Associated Aneurysms.

Central processes in the pathogenesis of TAV- (tricuspid aortic valve) and BAV- (bicuspid aortic valve) associated ascending thoracic aortic aneurysm (ATAA) development are still unknown. To gain new insights, we have collected aortic tissue and isolated smooth muscle cells of aneurysmal tissue and subjected them to in situ and in vitro analyses. We analyzed aortic tissue from 78 patients (31 controls, 28 TAV-ATAAs, and 19 BAV-ATAAs) and established 30 primary smooth muscle cell cultures. Analyses included histochemistry, immuno-, auto-fluorescence-based image analyses, and cellular analyses including smooth muscle cell contraction studies. With regard to TAV associated aneurysms, we observed a strong impairment of the vascular wall, which appears on different levels-structure and dimension of the layers (reduced media thickness, increased intima thickness, atherosclerotic changes, degeneration of aortic media, decrease of collagen, and increase of elastic fiber free area) as well as on the cellular level (accumulation of fibroblasts/myofibroblasts, and increase in the number of smooth muscle cells with a reduced alpha smooth muscle actin (α-SM actin) content per cell). The pathological changes in the aortic wall of BAV patients were much less pronounced-apart from an increased expression of osteopontin (OPN) in the vascular wall which stem from smooth muscle cells, we observed a trend towards increased calcification of the aortic wall (increase significantly associated with age). These observations provide strong evidence for different pathological processes and different disease mechanisms to occur in BAV- and TAV-associated aneurysms.

Shock complicating type A acute aortic dissection: Clinical correlates, management, and outcomes.

AIMS: Shock is among the most dreaded and common complications of type A acute aortic dissection (TAAAD). However, clinical correlates, management, and short- and long-term outcomes of TAAAD patients presenting with shock in real-world clinical practice are not known. METHODS AND RESULTS: We evaluated 2,704 patients with TAAAD enrolled in the International Registry of Acute Aortic Dissection between January 1, 1996, and August 18, 2012. On admission, 407 (15.1%) TAAAD patients presented with shock. Most in-hospital complications (coma, myocardial or mesenteric ischemia or infarction, and cardiac tamponade) were more frequent in shock patients. In-hospital mortality was significantly higher in TAAAD patients with than without shock (30.2% vs 23.9%, P=.007), regardless of surgical or medical treatment. Most shock patients underwent surgical repair, with medically managed patients demonstrating older age and more complications at presentation. Estimates using Kaplan-Meier survival analysis indicated that most (89%) TAAAD patients with shock discharged alive from the hospital survived 5years, a rate similar to that of TAAAD patients without shock (82%, P=.609). CONCLUSIONS: Shock occurred in 1 of 7 TAAAD patients and was associated with higher rates of in-hospital adverse events and mortality. However, TAAAD survivors with or without shock showed similar long-term mortality. Successful early and aggressive management of shock in TAAAD patients has the potential for improving long-term survival in this patient population.

Outcomes of patients presenting with acute type A aortic dissection in the setting of prior cardiac surgery: an analysis from the International Registry of Acute Aortic Dissection.

BACKGROUND: Prior cardiac surgery (PCS) can complicate the presentation and management of patients with type A acute aortic dissection (TAAAD). This report from the International Registry of Acute Aortic Dissection examines this hypothesis. METHODS AND RESULTS: A total of 352 of 2196 patients with TAAAD (16%) enrolled in the International Registry of Acute Aortic Dissection had cardiac surgery before dissection, including coronary artery bypass grafting (34%), aortic or mitral valve surgery (36%), aortic surgery (42%), and other cardiac surgery (16%). Those with PCS were older, had a higher frequency of diabetes mellitus, hypertension, and atherosclerosis, and presented later from symptom onset to hospital presentation and diagnosis (all P<0.05). In-hospital mortality was significantly higher for PCS patients (34% versus 23%; P<0.001). Five-year mortality was independently predicted by PCS (hazard ratio [HR], 2.04; 95% confidence interval [CI], 1.05-3.95), age >70 years (HR, 2.65; 95% CI, 1.40-5.05), medical management (HR, 5.10; 95% CI, 2.43-10.71), distal communication (HR, 2.64; 95% CI, 1.35-5.14), and coma (HR, 9.50; 95% CI, 2.05-44.05). Among patients with PCS, in-hospital (43% medical versus 30% surgical; P=0.033) and intermediate-term mortality was higher in patients with medical versus surgical management. Propensity-matched analysis revealed significant increase in mortality with medical management, but not with PCS. CONCLUSIONS: PCS delays presentation, diagnosis, and treatment of TAAAD and is an important adverse risk factor for early and intermediate-term mortality. This effect may be because of increased medical management in this patient population.

Stroke and outcomes in patients with acute type A aortic dissection.

BACKGROUND: Stroke is a highly dreaded complication of type A acute aortic dissection (TAAAD). However, little data exist on its incidence and association with prognosis. METHODS AND RESULTS: We evaluated 2202 patients with TAAAD (mean age 62 ± 14 years, 1487 [67.5%] men) from the International Registry of Acute Aortic Dissection to determine the incidence and prognostic impact of stroke in TAAAD. Stroke was present at arrival in 132 (6.0%) patients with TAAAD. These patients were older (65 ± 12 versus 62 ± 15 years; P=0.002) and more likely to have hypertension (86% versus 71%; P=0.001) or atherosclerosis (29% versus 22%; P=0.04) than patients without stroke. Chest pain at arrival was less common in patients with stroke (70% versus 82%; P<0.001), and patients with stroke presented more often with syncope (44% versus 15%; P<0.001), shock (14% versus 7%; P=0.005), or pulse deficit (51% versus 29%; P ≤ 0.001). Arch vessel involvement was more frequent among patients with stroke (68% versus 37%; P<0.001). They had less surgical management (74% versus 85%; P<0.001). Hospital stay was significantly longer in patients with stroke (median 17.9 versus 13.3 days; P<0.001). In-hospital complications, such as hypotension, coma, and malperfusion syndromes, and in-hospital mortality (adjusted odds ratio, 1.62; 95% confidence interval, 0.99-2.65) were higher among patients with stroke. Among hospital survivors, follow-up mortality was similar between groups (adjusted hazard ratio, 1.15; 95% confidence interval, 0.46-2.89). CONCLUSIONS: Stroke occurred in >1 of 20 patients with TAAAD and was associated with increased in-hospital morbidity but not long-term mortality. Whether aggressive early invasive interventions will reduce negative outcomes remains to be evaluated in future studies.

Emergency endovascular stent grafting in acute complicated type B dissection.

OBJECTIVE: The objective of this study was to assess midterm results of emergency endovascular stent grafting for patients with life-threatening complications of acute type B aortic dissection. METHODS: Between March 1999 and November 2011, 110 patients (86 men, 24 women) with complications of acute type B aortic dissection (mean age, 61 years; range, 19-87 years) were treated with thoracic endovascular aortic repair for malperfusion (55.5%) or aortic rupture (53.6%) in five major European referral centers and one U.S. referral center. Additional comorbidities included hypertension in 90 patients (82%), diabetes in 14 patients (13%), and chronic obstructive pulmonary disease in six patients (6%). Eleven patients (10%) had undergone previous aortic surgery. RESULTS: Overall hospital mortality was 12% (n = 13), with 14 late deaths after hospital discharge. In-hospital complications occurred in 32 patients (36%); 10 patients developed postoperative renal failure, five patients experienced new permanent neurologic symptoms, and six patients (5.4%) experienced retrograde type A aortic dissection. Furthermore, nine patients (8%) developed an early type I endoleak. Actuarial survival at 1 and 5 years was 85% and 73%, respectively. Postprocedural computed tomography angiography showed complete or partial thrombosis of the false lumen at the stent graft level in 61% and 23% of all patients, respectively. Freedom from treatment failure according to the Stanford classification was 82%, 75%, and 59% at 1, 3, and 5 years. CONCLUSIONS: Endovascular repair of complicated acute type B aortic dissection is proven to be a technically feasible and effective treatment modality in this relatively difficult patient cohort. Short-term and midterm results are persuasive; however, the long-term efficacy needs to be further evaluated.

Automated titanium fastener for surgical aortic valve replacement-preventive role for infective endocarditis?

OBJECTIVES: Evidence on long-term clinical outcomes considering suture-securing techniques used for surgical aortic valve replacement is still uncertain. METHODS: A total of 1405 patients who underwent surgical aortic valve replacement between January 2016 and December 2022 were included and grouped according to the suture-securing technique used (automated titanium fastener versus hand-tied knots). The occurrence of infective endocarditis during follow-up was set as the primary study end-point. As secondary study end-points, stroke, all-cause mortality and a composite outcome of either infective endocarditis, stroke, or all-cause mortality were assessed. RESULTS: The automated titanium fastener was used in 829 (59%) patients, whereas the hand-knot tying technique was used in 576 (41%) patients. The multivariable proportional competing risk regression analysis showed a significantly lower risk of infective endocarditis during follow-up in the automated titanium fastener group (adjusted sub-hazard ratio 0.44, 95% confidence interval 0.20-0.94, P = 0.035). The automated titanium fastener group was not associated with an increased risk of mortality or attaining the composite outcome, respectively (adjusted hazard ratio 0.81, 95% confidence interval 0.60-1.09, P = 0.169; adjusted hazard ratio 0.82, 95% confidence interval 0.63-1.07, P = 0.152). This group was not associated with an increased risk of stroke (adjusted sub-hazard ratio 0.82, 95% confidence interval 0.47-1.45, P = 0.504). Also, a significantly lower rate of early-onset infective endocarditis was observed in the automated titanium fastener group, (0.4% vs 1.4%, P = 0.032). CONCLUSIONS: Suture-securing with an automated titanium fastener device appears to be superior compared to the hand-knot tying technique in terms of lower risk of infective endocarditis.

Automated titanium fastener vs. hand-tied knots for prosthesis fixation in infective endocarditis.

Objectives: To date, there is no evidence regarding the safety of automated titanium fastener compared with hand-tied knots for prosthesis fixation in infective endocarditis. Methods: Between January 2016 and December 2022, a total of 220 patients requiring surgery for infective endocarditis were included in this retrospective analysis. The primary study endpoint was re-endocarditis during follow-up. The secondary study endpoints included stroke onset, all-cause mortality, and a composite outcome of either re-endocarditis, stroke, or all-cause mortality during follow-up. Results: Suture-securing with an automated titanium fastener was performed in 114 (51.8%) patients, whereas the conventional technique of hand knot-tying was used in 106 (48.2%) patients. The risk of re-endocarditis was significantly lower in the automated titanium fastener group, as shown in a multivariable proportional competing risk regression model (adjusted sub-hazard ratio 0.33, 95% confidence interval 0.11-0.99, p = 0.048). The multivariable Cox proportional hazards regression analysis showed that the automated titanium fastener group was not associated with an increased risk of stroke-onset or attaining the composite outcome, respectively, (adjusted hazard ratio 0.54, 95% confidence interval 0.27-1.08, p = 0.082), (adjusted hazard ratio 0.65, 95% confidence interval 0.42-1.02, p = 0.061). Also, this group was not associated with an increased risk of all-cause mortality, as demonstrated in the multivariable Poisson regression analysis (adjusted incidence-rate ratio 1.42, 95% confidence interval 0.83-2.42, p = 0.202). Conclusions: The use of automated titanium fastener device seems to be safe for infective endocarditis. Analyses of larger cohorts are required.

Neurological event rates and associated risk factors in acute type B aortic dissections treated by thoracic aortic endovascular repair.

OBJECTIVES: Thoracic endovascular aortic repair is the method of choice in patients with complicated type B acute aortic dissection. However, thoracic endovascular aortic repair carries a risk of periprocedural neurological events including stroke and spinal cord ischemia. We aimed to look at procedure-related neurological complications within a large cohort of patients with type B acute aortic dissection treated by thoracic endovascular aortic repair. METHODS: Between 1996 and 2021, the International Registry of Acute Aortic Dissection collected data on 3783 patients with type B acute aortic dissection. For this analysis, 648 patients with type B acute aortic dissection treated by thoracic endovascular aortic repair were included (69.4% male, mean age 62.7 ± 13.4 years). Patients were excluded who presented with a preexisting neurologic deficit or received adjunctive procedures. Demographics, clinical symptoms, and outcomes were analyzed. The primary end point was the periprocedural incidence of neurological events (defined as stroke, spinal cord ischemia, transient neurological deficit, or coma). Predictors for perioperative neurological events and follow-up outcomes were considered as secondary end points. RESULTS: Periprocedure neurological events were noted in 72 patients (11.1%) and included strokes (n = 29, 4.6%), spinal cord ischemias (n = 21, 3.3%), transient neurological deficits (n = 16, 2.6%), or coma (n = 6, 1.0%). The group with neurological events had a significantly higher in-hospital mortality (20.8% vs 4.3%, P < .001). Patients with neurological events were more likely to be female (40.3% vs 29.3%, P = .077), and aortic rupture was more often cited as an indication for thoracic endovascular aortic repair (38.8% vs 16.5%, P < .001). In patients with neurological events, more stent grafts were used (2 vs 1 stent graft, P = .002). Multivariable logistic regression analysis showed that aortic rupture (odds ratio, 3.12, 95% confidence interval, 1.44-6.78, P = .004) and female sex (odds ratio, 1.984, 95% confidence interval, 1.031-3.817, P = .040) were significantly associated with perioperative neurological events. CONCLUSIONS: In this highly selected group from dedicated aortic centers, more than 1 in 10 patients with type B acute aortic dissection treated by thoracic endovascular aortic repair had neurological events, in particular women. Further research is needed to identify the causes and presentation of these events after thoracic endovascular aortic repair, especially among women.

Innovative, simplified orthotopic lung transplantation in rats.

BACKGROUND: Various techniques of orthotopic single lung transplantation in rats have been reported; however, their widespread use has been limited owing to the complexity of the procedure. We report a novel microsurgical lung transplantation model in rats with a high survival rate that can be performed by one surgeon alone. METHODS: A total of 90 left lung allografts were transplanted from Fischer to Wistar Kyoto rats. We developed a triple axis precision system to place and stabilize the vascular clips intrathoracically to clamp the bronchovascular structures, thereby avoiding interference with the heart and contralateral lung movement. A single-suture bronchial anastomosis technique and proximal cuffing approach for vascular anastomosis was used, rendering surgical assistance unnecessary. RESULTS: In our recent series, both short-term (12 h) and long-term (21 d) survival was 100%. The lungs showed excellent perfusion and ventilation immediately on transplantation. Blood gas samples drawn from the left pulmonary vein and the histologic sections revealed excellent graft function. The donor operation lasted 20 ± 2 min, donor left lung dissection required 20 ± 2 min, and implantation required 90 ± 5 min. CONCLUSIONS: The present innovative method of left orthotopic single lung transplantation can be performed by one experienced surgeon alone, with excellent results and a high degree of reproducibility.

Aortic root geometry following composite valve graft implantation: Implications for future valve-in-valve procedures.

OBJECTIVES: Biological composite valve grafts (CVGs) are being performed more frequently, which increases the need for interventions treating bioprosthetic valve failure. The feasibility of valve-in-valve procedures in this population is uncertain. This study aimed to assess changes in aortic root geometry and coronary height following CVG implantation to better understand future interventions. METHODS: We retrospectively identified 64 patients following bioprosthetic CVG replacement with pre- and postoperative computed tomography angiography. Root assessment was conducted as in preprocedural transcatheter aortic valve evaluation using a virtual valve simulation. RESULTS: In 64 patients (age, 67.6 ± 9.3 years; 76.6% men) the preoperative coronary height was 14.3 ± 6.8 mm for the left coronary artery (LCA) and 17.9 ± 5.9 mm for the right coronary artery (RCA), which significantly decreased after CVG implantation, with 8.7 ± 4.4 mm for the LCA and 11.3 ± 4.4 mm for the RCA (P < .001). The virtual valve-to-coronary distances measured 4.0 ± 1.3 mm (LCA) and 4.6 ± 1.4 mm (RCA). Overall, 59.4% (n = 38) of patients with bio-CVGs would have been at risk for coronary obstruction, 29.7% (n = 19) for LCA, 10.9% (n = 7) for RCA, and 18.8% (n = 12) for combined LCA and RCA. CONCLUSIONS: Coronary height significantly decreased following CVG implantation. The majority of patients after bio-CVG were at a potential risk for coronary obstruction in future valve-in-valve procedures. Further studies are needed to identify the best possible technique for coronary reimplantation and other measures to diminish the risk for future coronary obstruction in this population.

Endovascular repair in type A aortic dissection: Anatomical candidacy for currently manufactured stent grafts and conceptual valve-carrying devices for an Endo-Bentall procedure.

OBJECTIVES: Endovascular treatment has been suggested as an alternative for open surgery for type A aortic dissection, but current devices have severe anatomical limitations. This study assesses the computed tomography-based anatomical suitability of currently manufactured stent grafts as well as 2 embodiments of valve-carrying devices. METHODS: In a retrospective single-centre cohort of 200 consecutive ascending/arch operations between 2009 and 2018, a total of 112 patients with type A aortic dissections were identified and evaluated for endovascular candidacy based on the locations of the entries, the landing zone diameters/lengths and the supra-aortic vessel origins according to the anatomical instructions for use criteria of 6 commercially available (tubular, branched or fenestrated) stent grafts. Two suggested valve-carrying devices with inner branches or fenestrations for the coronary arteries and branches for the supra-aortic vessels were also evaluated. RESULTS: The anatomical feasibility for commercial stent grafts ranged from 4% to 21%. The main limitations were proximal landing zone diameter (considering oversizing <15%), length due to dilatation and an entry too close to the sinotubular junction. For the valve-carrying conduits, anatomical feasibility was between 31% and 80%, with the main limiting factors being the diameter of the aortic annulus and its distance to the coronary arteries. CONCLUSIONS: The anatomical applicability of currently manufactured stent grafts for the treatment of type A aortic dissection is limited mainly by the absence of a suitable proximal landing zone in the ascending aorta and might substantially be improved by anchoring in the aortic annulus using a valve-carrying device that uses either fenestrations or branches for the coronary arteries.

Mechanical versus biological valve prostheses for left-sided infective endocarditis.

OBJECTIVES: Our aim was to analyse outcomes after implantation of mechanical versus biological valve prostheses in patients presenting with left-sided infective endocarditis. METHODS: We conducted a retrospective single-centre cohort study, analysing adults requiring valve surgery for left-sided infective endocarditis between January 2009 and December 2018 at the Department of Cardiac Surgery, Medical University of Vienna. The primary outcome variable was all-cause mortality. Secondary outcome variables included the occurrence of a combined event (death, stroke, intracerebral bleeding or reoperation) and the risk of re-endocarditis. RESULTS: Among 220 patients, 76 (34.5%) underwent mechanical valve replacement, while 144 (65.5%) underwent biological valve replacement. Recipients of mechanical valve prostheses were younger at the time of surgery and presented with lower European System for Cardiac Operative Risk Evaluation II values. In patients <55 years of age, implantation of a mechanical valve prosthesis was independently associated with significantly lower risk of all-cause mortality (adjusted hazard ratio 0.35, 95% confidence interval 0.15-0.80, P = 0.013). Moreover, this group was at significantly lower risk of a combined event (adjusted hazard ratio 0.38, 95% confidence interval 0.19-0.76, P = 0.006). Implantation of a mechanical valve prosthesis was not associated with increased risk of re-endocarditis. The presence of an annular abscess significantly increased the risk of re-endocarditis (adjusted hazard ratio 3.06, 95% confidence interval 1.40-6.71, P = 0.005). CONCLUSIONS: In patients presenting with left-sided infective endocarditis <55 years of age, implantation of a mechanical valve prosthesis is associated with superior outcomes. A prospective randomized controlled trial is warranted to confirm these results.